cell lines retained: Topics by Science.gov

Sample records for cell lines retained

Functional characterization of cell hybrids generated by induced fusion of primary porcine mesenchymal stem cells with an immortal murine cell line.

PubMed

Islam, M Q; Ringe, J; Reichmann, E; Migotti, R; Sittinger, M; da S Meirelles, L; Nardi, N B; Magnusson, P; Islam, K

2006-10-01

Bone marrow mesenchymal stem cells (MSC) integrate into various organs and contribute to the regeneration of diverse tissues. However, the mechanistic basis of the plasticity of MSC is not fully understood. The change of cell fate has been suggested to occur through cell fusion. We have generated hybrid cell lines by polyethylene-glycol-mediated cell fusion of primary porcine MSC with the immortal murine fibroblast cell line F7, a derivative of the GM05267 cell line. The hybrid cell lines display fibroblastic morphology and proliferate like immortal cells. They contain tetraploid to hexaploid porcine chromosomes accompanied by hypo-diploid murine chromosomes. Interestingly, many hybrid cell lines also express high levels of tissue-nonspecific alkaline phosphatase, which is considered to be a marker of undifferentiated embryonic stem cells. All tested hybrid cell lines retain osteogenic differentiation, a few of them also retain adipogenic potential, but none retain chondrogenic differentiation. Conditioned media from hybrid cells enhance the proliferation of both early-passage and late-passage porcine MSC, indicating that the hybrid cells secrete diffusible growth stimulatory factors. Murine F7 cells thus have the unique property of generating immortal cell hybrids containing unusually high numbers of chromosomes derived from normal cells. These hybrid cells can be employed in various studies to improve our understanding of regenerative biology. This is the first report, to our knowledge, describing the generation of experimentally induced cell hybrids by using normal primary MSC.
Human neuroblastoma cells with acquired resistance to the p53 activator RITA retain functional p53 and sensitivity to other p53 activating agents

PubMed Central

Michaelis, M; Rothweiler, F; Agha, B; Barth, S; Voges, Y; Löschmann, N; von Deimling, A; Breitling, R; Wilhelm Doerr, H; Rödel, F; Speidel, D; Cinatl, J

2012-01-01

Adaptation of wild-type p53 expressing UKF-NB-3 cancer cells to the murine double minute 2 inhibitor nutlin-3 causes de novo p53 mutations at high frequency (13/20) and multi-drug resistance. Here, we show that the same cells respond very differently when adapted to RITA, a drug that, like nutlin-3, also disrupts the p53/Mdm2 interaction. All of the 11 UKF-NB-3 sub-lines adapted to RITA that we established retained functional wild-type p53 although RITA induced a substantial p53 response. Moreover, all RITA-adapted cell lines remained sensitive to nutlin-3, whereas only five out of 10 nutlin-3-adapted cell lines retained their sensitivity to RITA. In addition, repeated adaptation of the RITA-adapted sub-line UKF-NB-3rRITA10 μM to nutlin-3 resulted in p53 mutations. The RITA-adapted UKF-NB-3 sub-lines displayed no or less pronounced resistance to vincristine, cisplatin, and irradiation than nutlin-3-adapted UKF-NB-3 sub-lines. Furthermore, adaptation to RITA was associated with fewer changes at the expression level of antiapoptotic factors than observed with adaptation to nutlin-3. Transcriptomic analyses indicated the RITA-adapted sub-lines to be more similar at the gene expression level to the parental UKF-NB-3 cells than nutlin-3-adapted UKF-NB-3 sub-lines, which correlates with the observed chemotherapy and irradiation sensitivity phenotypes. In conclusion, RITA-adapted cells retain functional p53, remain sensitive to nutlin-3, and display a less pronounced resistance phenotype than nutlin-3-adapted cells. PMID:22476102
Human neuroblastoma cells with acquired resistance to the p53 activator RITA retain functional p53 and sensitivity to other p53 activating agents.

PubMed

Michaelis, M; Rothweiler, F; Agha, B; Barth, S; Voges, Y; Löschmann, N; von Deimling, A; Breitling, R; Doerr, H Wilhelm; Rödel, F; Speidel, D; Cinatl, J

2012-04-05

Adaptation of wild-type p53 expressing UKF-NB-3 cancer cells to the murine double minute 2 inhibitor nutlin-3 causes de novo p53 mutations at high frequency (13/20) and multi-drug resistance. Here, we show that the same cells respond very differently when adapted to RITA, a drug that, like nutlin-3, also disrupts the p53/Mdm2 interaction. All of the 11 UKF-NB-3 sub-lines adapted to RITA that we established retained functional wild-type p53 although RITA induced a substantial p53 response. Moreover, all RITA-adapted cell lines remained sensitive to nutlin-3, whereas only five out of 10 nutlin-3-adapted cell lines retained their sensitivity to RITA. In addition, repeated adaptation of the RITA-adapted sub-line UKF-NB-3(r)RITA(10 μM) to nutlin-3 resulted in p53 mutations. The RITA-adapted UKF-NB-3 sub-lines displayed no or less pronounced resistance to vincristine, cisplatin, and irradiation than nutlin-3-adapted UKF-NB-3 sub-lines. Furthermore, adaptation to RITA was associated with fewer changes at the expression level of antiapoptotic factors than observed with adaptation to nutlin-3. Transcriptomic analyses indicated the RITA-adapted sub-lines to be more similar at the gene expression level to the parental UKF-NB-3 cells than nutlin-3-adapted UKF-NB-3 sub-lines, which correlates with the observed chemotherapy and irradiation sensitivity phenotypes. In conclusion, RITA-adapted cells retain functional p53, remain sensitive to nutlin-3, and display a less pronounced resistance phenotype than nutlin-3-adapted cells.
Establishment and characterization of fetal and maternal mesenchymal stem/stromal cell lines from the human term placenta.

PubMed

Qin, Sharon Q; Kusuma, Gina D; Al-Sowayan, Batla; Pace, Rishika A; Isenmann, Sandra; Pertile, Mark D; Gronthos, Stan; Abumaree, Mohamed H; Brennecke, Shaun P; Kalionis, Bill

2016-03-01

Human placental mesenchymal stem/stromal cells (MSC) are an attractive source of MSC with great therapeutic potential. However, primary MSC are difficult to study in vitro due to their limited lifespan and patient-to-patient variation. Fetal and maternal MSC were prepared from cells of the chorionic and basal plates of the placenta, respectively. Fetal and maternal MSC were transduced with the human telomerase reverse transcriptase (hTERT). Conventional stem cell assays assessed the MSC characteristics of the cell lines. Functional assays for cell proliferation, cell migration and ability to form colonies in soft agar were used to assess the whether transduced cells retained properties of primary MSC. Fetal chorionic and maternal MSC were successfully transduced with hTERT to create the cell lines CMSC29 and DMSC23 respectively. The lifespans of CMSC29 and DMSC23 were extended in cell culture. Both cell lines retained important MSC characteristics including cell surface marker expression and multipotent differentiation potential. Neither of the cell lines was tumourigenic in vitro. Gene expression differences were observed between CMSC29 and DMSC23 cells and their corresponding parent, primary MSC. Both cell lines show similar migration potential to their corresponding primary, parent MSC. The data show that transduced MSC retained important functional properties of the primary MSC. There were gene expression and functional differences between cell lines CMSC29 and DMSC23 that reflect their different tissue microenvironments of the parent, primary MSC. CMSC29 and DMSC23 cell lines could be useful tools for optimisation and functional studies of MSC. Copyright © 2016 Elsevier Ltd. All rights reserved.
Mouse Retinal Pigmented Epithelial Cell Lines retain their phenotypic characteristics after transfection with Human Papilloma Virus: A new tool to further the study of RPE biology

PubMed Central

Catanuto, Paola; Espinosa-Heidmann, Diego; Pereira-Simon, Simone; Sanchez, Patricia; Salas, Pedro; Hernandez, Eleut; Cousins, Scott W.; Elliot, Sharon J.

2009-01-01

Development of immortalized mouse retinal pigmented epithelial cell (RPE) lines that retain many of their in vivo phenotypic characteristics, would aid in studies of ocular diseases including age related macular degeneration (AMD). RPE cells were isolated from 16 month old (estrogen receptor knockout) ERKOα and ERKOβ mice and their C57Bl/6 wild type littermates. RPE65 and cellular retinaldehyde binding protein (CRALBP) expression, in vivo markers of RPE cells, were detected by real-time RT-PCR and western analysis. We confirmed the presence of epithelial cell markers, ZO1, cytokeratin 8 and 18 by immunofluorescence staining. In addition, we confirmed the distribution of actin filaments and the expression of ezrin. To develop cell lines, RPE cells were isolated, propagated and immortalized using human papilloma virus (HPV) 16 (E6/E7). RPE-specific markers and morphology were assessed before and after immortalization. In wildtype littermate controls, there was no evidence of any alterations in the parameters that we examined including MMP-2, TIMP-2, collagen type IV, and estrogen receptor (ER) α and ERβ protein expression and ER copy number ratio. Therefore, immortalized mouse RPE cell lines that retain their in vivo phenotype can be isolated from either pharmacologically or genetically manipulated mice, and may be used to study RPE cell biology. PMID:19013153
Conditionally immortalized stem cell lines from human spinal cord retain regional identity and generate functional V2a interneurons and motorneurons.

PubMed

Cocks, Graham; Romanyuk, Nataliya; Amemori, Takashi; Jendelova, Pavla; Forostyak, Oksana; Jeffries, Aaron R; Perfect, Leo; Thuret, Sandrine; Dayanithi, Govindan; Sykova, Eva; Price, Jack

2013-06-07

The use of immortalized neural stem cells either as models of neural development in vitro or as cellular therapies in central nervous system (CNS) disorders has been controversial. This controversy has centered on the capacity of immortalized cells to retain characteristic features of the progenitor cells resident in the tissue of origin from which they were derived, and the potential for tumorogenicity as a result of immortalization. Here, we report the generation of conditionally immortalized neural stem cell lines from human fetal spinal cord tissue, which addresses these issues. Clonal neural stem cell lines were derived from 10-week-old human fetal spinal cord and conditionally immortalized with an inducible form of cMyc. The derived lines were karyotyped, transcriptionally profiled by microarray, and assessed against a panel of spinal cord progenitor markers with immunocytochemistry. In addition, the lines were differentiated and assessed for the presence of neuronal fate markers and functional calcium channels. Finally, a clonal line expressing eGFP was grafted into lesioned rat spinal cord and assessed for survival, differentiation characteristics, and tumorogenicity. We demonstrate that these clonal lines (a) retain a clear transcriptional signature of ventral spinal cord progenitors and a normal karyotype after extensive propagation in vitro, (b) differentiate into relevant ventral neuronal subtypes with functional T-, L-, N-, and P/Q-type Ca(2+) channels and spontaneous calcium oscillations, and (c) stably engraft into lesioned rat spinal cord without tumorogenicity. We propose that these cells represent a useful tool both for the in vitro study of differentiation into ventral spinal cord neuronal subtypes, and for examining the potential of conditionally immortalized neural stem cells to facilitate functional recovery after spinal cord injury or disease.
Immortalized Mouse Floxed Fam20c Dental Papillar Mesenchymal and Osteoblast Cell Lines Retain Their Primary Characteristics

PubMed Central

Liu, Chao; Wang, Xiaofang; Zhang, Hua; Xie, Xiaohua; Liu, Peihong; Liu, Ying; Jani, Priyam H.; Lu, Yongbo; Chen, Shuo; Qin, Chunlin

2016-01-01

Fam20c is essential for the normal mineralization of dentin and bone. The generation of odontoblast and osteoblast cell lines carrying floxed Fam20c allele can offer valuable tools for the study of the roles of Fam20c in the mineralization of dentin and bone. The limited capability of the primary odontoblasts and osteoblasts to proliferate necessitates the development of odontoblast and osteoblast cell lines serving as substitutes for the study of differentiation and mineralization of the odontoblasts and osteoblasts. In this study, we established and characterized immortalized mouse floxed Fam20c dental papilla mesenchymal and osteoblast cell lines. The isolated primary mouse floxed Fam20c dental papilla mesenchymal cells and osteoblasts were immortalized by the infection of lentivirus containing Simian Virus 40 T-antigen (SV40 T-Ag). The immortalization of floxed Fam20c dental papilla mesenchymal cells and osteoblasts was verified by the long-term passages and genomic integration of SV40 T-Ag. The immortalized floxed Fam20c dental papilla mesenchymal and osteoblast cell lines not only proliferated at a high rate and retained the morphology of their primary counterparts, but also preserved the dentin and bone specific gene expression as the primary dental papilla mesenchymal cells and osteoblasts did. Consistently, the capability of the primary floxed Fam20c dental papilla mesenchymal cells and osteoblasts to mineralize was also inherited by the immortalized dental papilla mesenchymal and osteoblast cell lines. Thus, we have successfully generated the immortalized mouse floxed Fam20c dental papilla mesenchymal and osteoblast cell lines. PMID:25833681
Derivation and characterization of putative embryonic stem cells from cloned rabbit embryos.

PubMed

Intawicha, Payungsuk; Siriboon, Chawalit; Chen, Chien-Hong; Chiu, Yung-Tsung; Lin, Tzu-An; Kere, Michel; Lo, Neng-Wen; Lee, Kun-Hsiung; Chang, Li-Yung; Chiang, Hsing-I; Ju, Jyh-Cherng

2016-10-15

The present study aimed to establish embryonic stem (ES) cell lines, i.e., ntES cells, using rabbit blastocyst stage embryos cloned by somatic cell nuclear transfer. First, we investigated the development of cloned rabbit embryos reconstructed with normal fibroblasts and fibroblasts transfected with enhanced green fluorescence protein (eGFP). Blastocyst rates were 27.4% and 23.9%, respectively, for the embryos reconstructed with normal fibroblasts and fibroblasts transfected with eGFP compared with that from the parthenogenetic group (43.1%). One ntES cell line was established from embryos reconstructed with eGFP-transfected fibroblasts (1 of 17, 5.9%), and three ntES cell lines were derived from those with normal fibroblasts (3 of 17, 17.6%). All the ntES cell lines retained alkaline phosphatase activity and expressed ES cell-specific markers SSEA-4, Oct-4, TRA-1-60, and TRA-1-81. The pluripotency was further confirmed by reverse transcription-polymerase chain reaction analyses of Oct-4, Nanog, and Sox-2 expressions in ntES cell lines. The differentiation capacity of ntES cells was also examined in vitro and in vivo, by which these ntES cell lines were able to differentiate into all three germ layers through embryoid bodies and teratomas. In conclusion, it is apparent that the efficiency of ntES cells derived using eGFP-transfected donor cells is lower than that with nontransfected, normal fibroblasts donor cells. Similar to those from parthenogenetic embryos, all ntES cell lines derived from cloned rabbit embryos are able to express pluripotency markers and retain their capability to differentiate into various cell lineages both in vitro and in vivo. Copyright © 2016 Elsevier Inc. All rights reserved.
Immortalized Human Schwann Cell Lines Derived From Tumors of Schwannomatosis Patients.

PubMed

Ostrow, Kimberly Laskie; Donaldson, Katelyn; Blakeley, Jaishri; Belzberg, Allan; Hoke, Ahmet

2015-01-01

Schwannomatosis, a rare form of neurofibromatosis, is characterized predominantly by multiple, often painful, schwannomas throughout the peripheral nervous system. The current standard of care for schwannomatosis is surgical resection. A major obstacle to schwannomatosis research is the lack of robust tumor cell lines. There is a great need for mechanistic and drug discovery studies of schwannomatosis, yet appropriate tools are not currently available. Schwannomatosis tumors are difficult to grow in culture as they survive only a few passages before senescence. Our lab has extensive experience in establishing primary and immortalized human Schwann cell cultures from normal tissue that retain their phenotypes after immortalization. Therefore we took on the challenge of creating immortalized human Schwann cell lines derived from tumors from schwannomatosis patients. We have established and fully characterized 2 schwannomatosis cell lines from 2 separate patients using SV40 virus large T antigen. One patient reported pain and the other did not. The schwannomatosis cell lines were stained with S100B antibodies to confirm Schwann cell identity. The schwannomatosis cells also expressed the Schwann cell markers, p75NTR, S100B, and NGF after multiple passages. Cell morphology was retained following multiple passaging and freeze/ thaw cycles. Gene expression microarray analysis was used to compare the cell lines with their respective parent tumors. No differences in key genes were detected, with the exception that several cell cycle regulators were upregulated in the schwannomatosis cell lines when compared to their parent tumors. This upregulation was apparently a product of cell culturing, as the schwannomatosis cells exhibited the same expression pattern of cell cycle regulatory genes as normal primary human Schwann cells. Cell growth was also similar between normal primary and immortalized tumor cells in culture. Accurate cell lines derived directly from human tumors will serve as invaluable tools for advancing schwannomatosis research, including drug screening.
Immortalized Human Schwann Cell Lines Derived From Tumors of Schwannomatosis Patients

PubMed Central

Ostrow, Kimberly Laskie; Donaldson, Katelyn; Blakeley, Jaishri; Belzberg, Allan; Hoke, Ahmet

2015-01-01

Schwannomatosis, a rare form of neurofibromatosis, is characterized predominantly by multiple, often painful, schwannomas throughout the peripheral nervous system. The current standard of care for schwannomatosis is surgical resection. A major obstacle to schwannomatosis research is the lack of robust tumor cell lines. There is a great need for mechanistic and drug discovery studies of schwannomatosis, yet appropriate tools are not currently available. Schwannomatosis tumors are difficult to grow in culture as they survive only a few passages before senescence. Our lab has extensive experience in establishing primary and immortalized human Schwann cell cultures from normal tissue that retain their phenotypes after immortalization. Therefore we took on the challenge of creating immortalized human Schwann cell lines derived from tumors from schwannomatosis patients. We have established and fully characterized 2 schwannomatosis cell lines from 2 separate patients using SV40 virus large T antigen. One patient reported pain and the other did not. The schwannomatosis cell lines were stained with S100B antibodies to confirm Schwann cell identity. The schwannomatosis cells also expressed the Schwann cell markers, p75NTR, S100B, and NGF after multiple passages. Cell morphology was retained following multiple passaging and freeze/ thaw cycles. Gene expression microarray analysis was used to compare the cell lines with their respective parent tumors. No differences in key genes were detected, with the exception that several cell cycle regulators were upregulated in the schwannomatosis cell lines when compared to their parent tumors. This upregulation was apparently a product of cell culturing, as the schwannomatosis cells exhibited the same expression pattern of cell cycle regulatory genes as normal primary human Schwann cells. Cell growth was also similar between normal primary and immortalized tumor cells in culture. Accurate cell lines derived directly from human tumors will serve as invaluable tools for advancing schwannomatosis research, including drug screening. PMID:26657314
Immortalized Mouse Floxed Fam20c Dental Papillar Mesenchymal and Osteoblast Cell Lines Retain Their Primary Characteristics.

PubMed

Liu, Chao; Wang, Xiaofang; Zhang, Hua; Xie, Xiaohua; Liu, Peihong; Liu, Ying; Jani, Priyam H; Lu, Yongbo; Chen, Shuo; Qin, Chunlin

2015-11-01

Fam20c is essential for the normal mineralization of dentin and bone. The generation of odontoblast and osteoblast cell lines carrying floxed Fam20c allele can offer valuable tools for the study of the roles of Fam20c in the mineralization of dentin and bone. The limited capability of the primary odontoblasts and osteoblasts to proliferate necessitates the development of odontoblast and osteoblast cell lines serving as substitutes for the study of differentiation and mineralization of the odontoblasts and osteoblasts. In this study, we established and characterized immortalized mouse floxed Fam20c dental papilla mesenchymal and osteoblast cell lines. The isolated primary mouse floxed Fam20c dental papilla mesenchymal cells and osteoblasts were immortalized by the infection of lentivirus containing Simian Virus 40 T-antigen (SV40 T-Ag). The immortalization of floxed Fam20c dental papilla mesenchymal cells and osteoblasts was verified by the long-term passages and genomic integration of SV40 T-Ag. The immortalized floxed Fam20c dental papilla mesenchymal and osteoblast cell lines not only proliferated at a high rate and retained the morphology of their primary counterparts, but also preserved the dentin and bone specific gene expression as the primary dental papilla mesenchymal cells and osteoblasts did. Consistently, the capability of the primary floxed Fam20c dental papilla mesenchymal cells and osteoblasts to mineralize was also inherited by the immortalized dental papilla mesenchymal and osteoblast cell lines. Thus, we have successfully generated the immortalized mouse floxed Fam20c dental papilla mesenchymal and osteoblast cell lines. © 2015 Wiley Periodicals, Inc.
Newly-derived neuroblastoma cell lines propagated in serum-free media recapitulate the genotype and phenotype of primary neuroblastoma tumours.

PubMed

Bate-Eya, Laurel T; Ebus, Marli E; Koster, Jan; den Hartog, Ilona J M; Zwijnenburg, Danny A; Schild, Linda; van der Ploeg, Ida; Dolman, M Emmy M; Caron, Huib N; Versteeg, Rogier; Molenaar, Jan J

2014-02-01

Recently protocols have been devised for the culturing of cell lines from fresh tumours under serum-free conditions in defined neural stem cell medium. These cells, frequently called tumour initiating cells (TICs) closely retained characteristics of the tumours of origin. We report the isolation of eight newly-derived neuroblastoma TICs from six primary neuroblastoma tumours and two bone marrow metastases. The primary tumours from which these TICs were generated have previously been fully typed by whole genome sequencing (WGS). Array comparative genomic hybridisation (aCGH) analysis showed that TIC lines retained essential characteristics of the primary tumours and exhibited typical neuroblastoma chromosomal aberrations such as MYCN amplification, gain of chromosome 17q and deletion of 1p36. Protein analysis showed expression for neuroblastoma markers MYCN, NCAM, CHGA, DBH and TH while haematopoietic markers CD19 and CD11b were absent. We analysed the growth characteristics and confirmed tumour-forming potential using sphere-forming assays, subcutaneous and orthotopic injection of these cells into immune-compromised mice. Affymetrix mRNA expression profiling of TIC line xenografts showed an expression pattern more closely mimicking primary tumours compared to xenografts from classical cell lines. This establishes that these neuroblastoma TICs cultured under serum-free conditions are relevant and useful neuroblastoma tumour models. Copyright © 2013 Elsevier Ltd. All rights reserved.
The use of human tumour cell lines in the discovery of new cancer chemotherapeutic drugs.

PubMed

Baguley, Bruce C; Marshall, Elaine S

2008-02-01

Human tumour cell lines have played a major role in anticancer drug discovery, but cell lines may model only some aspects of tumour behaviour in cancer patients. Growing evidence supports a theory that stem cells with self-renewing properties sustain tumours. This review considers the extent to which a deeper understanding of the origin and properties of tumour cell lines might lead to new strategies for anticancer drug discovery. Recent literature on normal and tumour stem cells is reviewed and placed in the context of a discussion on the derivation and properties of tumour cell lines. Early-passage cell lines may model the more rapidly proliferating cells in human tumours and, thus, retain some of the properties of tumour stem cells. The effects of anticancer drugs on cell lines should be considered not only with regards to the induction of apoptosis, but also to the induction of senescence or other pathways that lead to host immune and inflammatory responses.
Phenotypes and Karyotypes of Human Malignant Mesothelioma Cell Lines

PubMed Central

Relan, Vandana; Morrison, Leanne; Parsonson, Kylie; Clarke, Belinda E.; Duhig, Edwina E.; Windsor, Morgan N.; Matar, Kevin S.; Naidoo, Rishendran; Passmore, Linda; McCaul, Elizabeth; Courtney, Deborah; Yang, Ian A.; Fong, Kwun M.; Bowman, Rayleen V.

2013-01-01

Background Malignant mesothelioma is an aggressive tumour of serosal surfaces most commonly pleura. Characterised cell lines represent a valuable tool to study the biology of mesothelioma. The aim of this study was to develop and biologically characterise six malignant mesothelioma cell lines to evaluate their potential as models of human malignant mesothelioma. Methods Five lines were initiated from pleural biopsies, and one from pleural effusion of patients with histologically proven malignant mesothelioma. Mesothelial origin was assessed by standard morphology, Transmission Electron Microscopy (TEM) and immunocytochemistry. Growth characteristics were assayed using population doubling times. Spectral karyotyping was performed to assess chromosomal abnormalities. Authentication of donor specific derivation was undertaken by DNA fingerprinting using a panel of SNPs. Results Most of cell lines exhibited spindle cell shape, with some retaining stellate shapes. At passage 2 to 6 all lines stained positively for calretinin and cytokeratin 19, and demonstrated capacity for anchorage-independent growth. At passage 4 to 16, doubling times ranged from 30–72 hours, and on spectral karyotyping all lines exhibited numerical chromosomal abnormalities ranging from 41 to 113. Monosomy of chromosomes 8, 14, 22 or 17 was observed in three lines. One line displayed four different karyotypes at passage 8, but only one karyotype at passage 42, and another displayed polyploidy at passage 40 which was not present at early passages. At passages 5–17, TEM showed characteristic features of mesothelioma ultrastructure in all lines including microvilli and tight intercellular junctions. Conclusion These six cell lines exhibit varying cell morphology, a range of doubling times, and show diverse passage-dependent structural chromosomal changes observed in malignant tumours. However they retain characteristic immunocytochemical protein expression profiles of mesothelioma during maintenance in artificial culture systems. These characteristics support their potential as in vitro model systems for studying cellular, molecular and genetic aspects of mesothelioma. PMID:23516439
Generation of a human airway epithelium derived basal cell line with multipotent differentiation capacity

PubMed Central

2013-01-01

Background As the multipotent progenitor population of the airway epithelium, human airway basal cells (BC) replenish the specialized differentiated cell populations of the mucociliated airway epithelium during physiological turnover and repair. Cultured primary BC divide a limited number of times before entering a state of replicative senescence, preventing the establishment of long-term replicating cultures of airway BC that maintain their original phenotype. Methods To generate an immortalized human airway BC cell line, primary human airway BC obtained by brushing the airway epithelium of healthy nonsmokers were infected with a retrovirus expressing human telomerase (hTERT). The resulting immortalized cell line was then characterized under non-differentiating and differentiating air-liquid interface (ALI) culture conditions using ELISA, TaqMan quantitative PCR, Western analysis, and immunofluorescent and immunohistochemical staining analysis for cell type specific markers. In addition, the ability of the cell line to respond to environmental stimuli under differentiating ALI culture was assessed. Results We successfully generated an immortalized human airway BC cell line termed BCi-NS1 via expression of hTERT. A single cell derived clone from the parental BCi-NS1 cells, BCi-NS1.1, retains characteristics of the original primary cells for over 40 passages and demonstrates a multipotent differentiation capacity into secretory (MUC5AC, MUC5B), goblet (TFF3), Clara (CC10) and ciliated (DNAI1, FOXJ1) cells on ALI culture. The cells can respond to external stimuli such as IL-13, resulting in alteration of the normal differentiation process. Conclusion Development of immortalized human airway BC that retain multipotent differentiation capacity over long-term culture should be useful in understanding the biology of BC, the response of BC to environmental stress, and as a target for assessment of pharmacologic agents. PMID:24298994
[Establishment of human embryonic stem cell lines and their therapeutic application].

PubMed

Suemori, Hirofumi

2004-03-01

Embryonic stem (ES) cell lines are pluripotent stem cell lines that can be propagated indefinitely in culture, retaining their potency to differentiate into every type of cell and tissue in the body. ES cell lines were first established from mouse blastocysts, and have been used for research in developmental biology. ES cells have been proven to be very valuable in the genetic modification of the mouse, especially in producing knockout mice. Since establishment of human ES cell lines was reported, their use in cell replacement therapies has been enthusiastically expected. There have been reports of the differentiation of several useful cell types from human ES cell lines, and clinical use of functional tissues and cells from human ES cells is anticipated. In Japan, there have also been many demands for the use of human ES cells in basic and pre-clinical research. We obtained governmental permission to establish human ES cell lines in April 2002 and started research using donated frozen embryos in January 2003. We successfully established three ES cell line from three blastocysts. These cell lines will be distributed at cost to researchers who have governmental permission to use human ES cells.
A Medium-Throughput Single Cell CRISPR-Cas9 Assay to Assess Gene Essentiality.

PubMed

Grassian, A R; Scales, T M E; Knutson, S K; Kuntz, K W; McCarthy, N J; Lowe, C E; Moore, J D; Copeland, R A; Keilhack, H; Smith, J J; Wickenden, J A; Ribich, S

2015-01-01

Target selection for oncology is a crucial step in the successful development of therapeutics. Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 editing of specific loci offers an alternative method to RNA interference and small molecule inhibitors for determining whether a cell line is dependent on a specific gene product for proliferation or survival. In our initial studies using CRISPR-Cas9 to verify the dependence on EZH2 activity for proliferation of a SMARCB1/SNF5/INI1 mutant malignant rhabdoid tumor (MRT) cell line, we noted that the initial reduction in proliferation was lost over time. We hypothesized that in the few cells that retain proliferative capacity, at least one allele of EZH2 remains functional. To verify this, we developed an assay to analyze 10s-100s of clonal cell populations for target gene disruption using restriction digest and fluorescent fragment length analyses. Our results clearly show that in cell lines in which EZH2 is essential for proliferation, at least one potentially functional allele of EZH2 is retained in the clones that survive. This assay clearly indicates whether or not a specific gene is essential for survival and/or proliferation in a given cell line. Such data can aid the development of more robust therapeutics by increasing confidence in target selection.
Mapping the cellular and molecular heterogeneity of normal and malignant breast tissues and cultured cell lines

PubMed Central

2010-01-01

Introduction Normal and neoplastic breast tissues are comprised of heterogeneous populations of epithelial cells exhibiting various degrees of maturation and differentiation. While cultured cell lines have been derived from both normal and malignant tissues, it remains unclear to what extent they retain similar levels of differentiation and heterogeneity as that found within breast tissues. Methods We used 12 reduction mammoplasty tissues, 15 primary breast cancer tissues, and 20 human breast epithelial cell lines (16 cancer lines, 4 normal lines) to perform flow cytometry for CD44, CD24, epithelial cell adhesion molecule (EpCAM), and CD49f expression, as well as immunohistochemistry, and in vivo tumor xenograft formation studies to extensively analyze the molecular and cellular characteristics of breast epithelial cell lineages. Results Human breast tissues contain four distinguishable epithelial differentiation states (two luminal phenotypes and two basal phenotypes) that differ on the basis of CD24, EpCAM and CD49f expression. Primary human breast cancer tissues also contain these four cellular states, but in altered proportions compared to normal tissues. In contrast, cultured cancer cell lines are enriched for rare basal and mesenchymal epithelial phenotypes, which are normally present in small numbers within human tissues. Similarly, cultured normal human mammary epithelial cell lines are enriched for rare basal and mesenchymal phenotypes that represent a minor fraction of cells within reduction mammoplasty tissues. Furthermore, although normal human mammary epithelial cell lines exhibit features of bi-potent progenitor cells they are unable to differentiate into mature luminal breast epithelial cells under standard culture conditions. Conclusions As a group breast cancer cell lines represent the heterogeneity of human breast tumors, but individually they exhibit increased lineage-restricted profiles that fall short of truly representing the intratumoral heterogeneity of individual breast tumors. Additionally, normal human mammary epithelial cell lines fail to retain much of the cellular diversity found in human breast tissues and are enriched for differentiation states that are a minority in breast tissues, although they do exhibit features of bi-potent basal progenitor cells. These findings suggest that collections of cell lines representing multiple cell types can be used to model the cellular heterogeneity of tissues. PMID:20964822
Telomerase-immortalized non-malignant human prostate epithelial cells retain the properties of multipotent stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li Hongzhen; Zhou Jianjun; Miki, Jun

2008-01-01

Understanding prostate stem cells may provide insight into the origin of prostate cancer. Primary cells have been cultured from human prostate tissue but they usually survive only 15-20 population doublings before undergoing senescence. We report here that RC-170N/h/clone 7 cells, a clonal cell line from hTERT-immortalized primary non-malignant tissue-derived human prostate epithelial cell line (RC170N/h), retain multipotent stem cell properties. The RC-170N/h/clone 7 cells expressed a human embryonic stem cell marker, Oct-4, and potential prostate epithelial stem cell markers, CD133, integrin {alpha}2{beta}1{sup hi} and CD44. The RC-170N/h/clone 7 cells proliferated in KGM and Dulbecco's Modified Eagle Medium with 10% fetalmore » bovine serum and 5 {mu}g/ml insulin (DMEM + 10% FBS + Ins.) medium, and differentiated into epithelial stem cells that expressed epithelial cell markers, including CK5/14, CD44, p63 and cytokeratin 18 (CK18); as well as the mesenchymal cell markers, vimentin, desmin; the neuron and neuroendocrine cell marker, chromogranin A. Furthermore the RC170 N/h/clone 7 cells differentiated into multi tissues when transplanted into the sub-renal capsule and subcutaneously of NOD-SCID mice. The results indicate that RC170N/h/clone 7 cells retain the properties of multipotent stem cells and will be useful as a novel cell model for studying the mechanisms of human prostate stem cell differentiation and transformation.« less
Generation of human cortical neurons from a new immortal fetal neural stem cell line.

PubMed

Cacci, E; Villa, A; Parmar, M; Cavallaro, M; Mandahl, N; Lindvall, O; Martinez-Serrano, A; Kokaia, Z

2007-02-01

Isolation and expansion of neural stem cells (NSCs) of human origin are crucial for successful development of cell therapy approaches in neurodegenerative diseases. Different epigenetic and genetic immortalization strategies have been established for long-term maintenance and expansion of these cells in vitro. Here we report the generation of a new, clonal NSC (hc-NSC) line, derived from human fetal cortical tissue, based on v-myc immortalization. Using immunocytochemistry, we show that these cells retain the characteristics of NSCs after more than 50 passages. Under proliferation conditions, when supplemented with epidermal and basic fibroblast growth factors, the hc-NSCs expressed neural stem/progenitor cell markers like nestin, vimentin and Sox2. When growth factors were withdrawn, proliferation and expression of v-myc and telomerase were dramatically reduced, and the hc-NSCs differentiated into glia and neurons (mostly glutamatergic and GABAergic, as well as tyrosine hydroxylase-positive, presumably dopaminergic neurons). RT-PCR analysis showed that the hc-NSCs retained expression of Pax6, Emx2 and Neurogenin2, which are genes associated with regionalization and cell commitment in cortical precursors during brain development. Our data indicate that this hc-NSC line could be useful for exploring the potential of human NSCs to replace dead or damaged cortical cells in animal models of acute and chronic neurodegenerative diseases. Taking advantage of its clonality and homogeneity, this cell line will also be a valuable experimental tool to study the regulatory role of intrinsic and extrinsic factors in human NSC biology.

Differential splicing of oncogenes and tumor suppressor genes in African and Caucasian American populations: contributing factor in prostate cancer disparities

DTIC Science & Technology

2017-12-01

exhibited enhanced activation of the PI3K/AKT pathway compared to the same lines over-expressing the CA- enriched long (-L) variant PIK3CD-L (retains...demonstrate that FGFR3-S: i) encodes a more aggressive oncogenic signaling protein compared to CA-enriched FGFR3-L (retains exon 14) as defined by in vitro...into PCa cell lines for in vitro and in vivo investigations completed in Year 1 (see description below). 3 FIGURE 1. Full-length cDNA
Generation of human cortical neurons from a new immortal fetal neural stem cell line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cacci, E.; Villa, A.; Parmar, M.

2007-02-01

Isolation and expansion of neural stem cells (NSCs) of human origin are crucial for successful development of cell therapy approaches in neurodegenerative diseases. Different epigenetic and genetic immortalization strategies have been established for long-term maintenance and expansion of these cells in vitro. Here we report the generation of a new, clonal NSC (hc-NSC) line, derived from human fetal cortical tissue, based on v-myc immortalization. Using immunocytochemistry, we show that these cells retain the characteristics of NSCs after more than 50 passages. Under proliferation conditions, when supplemented with epidermal and basic fibroblast growth factors, the hc-NSCs expressed neural stem/progenitor cell markersmore » like nestin, vimentin and Sox2. When growth factors were withdrawn, proliferation and expression of v-myc and telomerase were dramatically reduced, and the hc-NSCs differentiated into glia and neurons (mostly glutamatergic and GABAergic, as well as tyrosine hydroxylase-positive, presumably dopaminergic neurons). RT-PCR analysis showed that the hc-NSCs retained expression of Pax6, Emx2 and Neurogenin2, which are genes associated with regionalization and cell commitment in cortical precursors during brain development. Our data indicate that this hc-NSC line could be useful for exploring the potential of human NSCs to replace dead or damaged cortical cells in animal models of acute and chronic neurodegenerative diseases. Taking advantage of its clonality and homogeneity, this cell line will also be a valuable experimental tool to study the regulatory role of intrinsic and extrinsic factors in human NSC biology.« less
Hypermethylation of the TSLC1 Gene Promoter in Primary Gastric Cancers and Gastric Cancer Cell Lines

PubMed Central

Honda, Teiichiro; Waki, Takayoshi; Jin, Zhe; Sato, Kiyoshi; Motoyama, Teiichi; Kawata, Sumio; Kimura, Wataru; Nishizuka, Satoshi; Murakami, Yoshinori

2002-01-01

The TSLC1 (tumor suppressor in lung cancer–1) gene is a novel tumor suppressor gene on chromosomal region 11q23.2, and is frequently inactivated by concordant promoter hypermethylation and loss of heterozygosity (LOH) in non‐small cell lung cancer (NSCLC). Because LOH on 11q has also been observed frequently in other human neoplasms including gastric cancer, we investigated the promoter methylation status of TSLC1 in 10 gastric cancer cell lines and 97 primary gastric cancers, as well as the corresponding non‐cancerous gastric tissues, by bisulfite‐SSCP analysis followed by direct sequencing. Allelic status of the TSLC1 gene was also investigated in these cell lines and primary gastric cancers. The TSLC1 promoter was methylated in two gastric cancer cell lines, KATO‐III and ECC10, and in 15 out of 97 (16%) primary gastric cancers. It was not methylated in non‐cancerous gastric tissues, suggesting that this hypermethylation is a cancer‐specific alteration. KATO‐III and ECC10 cells retained two alleles of TSLC1, both of which showed hypermethylation, associated with complete loss of gene expression. Most of the primary gastric cancers with promoter methylation also retained heterozygosity at the TSLC1 locus on 11q23.2. These data indicate that bi‐allelic hypermethylation of the TSLC1 promoter and resulting gene silencing occur in a subset of primary gastric cancers. PMID:12716461
Generation of an induced pluripotent stem cell line from chorionic villi of a Turner syndrome spontaneous abortion.

PubMed

Parveen, Shagufta; Panicker, M M; Gupta, Pawan Kumar

2017-03-01

A major cause of spontaneous abortions is chromosomal abnormality of foetal cells. We report the generation of an induced pluripotent stem cell line from the fibroblasts isolated from chorionic villi of an early spontaneously aborted foetus with Turner syndrome. The Turner syndrome villus induced pluripotent stem cell line is transgene free, retains the original XO karyotype, expresses pluripotency markers and undergoes trilineage differentiation. This pluripotent stem cell model of Turner syndrome should serve as a tool to study the developmental abnormalities of foetus and placenta that lead to early embryo lethality and profound symptoms like infertility in 45 XO survivors. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Immortalization of pig fibroblast cells by transposon-mediated ectopic expression of porcine telomerase reverse transcriptase.

PubMed

He, Shan; Li, Yangyang; Chen, Yang; Zhu, Yue; Zhang, Xinyu; Xia, Xiaoli; Sun, Huaichang

2016-08-01

Pigs are the most economically important livestock, but pig cell lines useful for physiological studies and/or vaccine development are limited. Although several pig cell lines have been generated by oncogene transformation or human telomerase reverse transcriptase (TERT) immortalization, these cell lines contain viral sequences and/or antibiotic resistance genes. In this study, we established a new method for generating pig cell lines using the Sleeping Beauty (SB) transposon-mediated ectopic expression of porcine telomerase reverse transcriptase (pTERT). The performance of the new method was confirmed by generating a pig fibroblast cell (PFC) line. After transfection of primary PFCs with the SB transposon system, one cell clone containing the pTERT expression cassette was selected by dilution cloning and passed for different generations. After passage for more than 40 generations, the cell line retained stable expression of ectopic pTERT and continuous growth potential. Further characterization showed that the cell line kept the fibroblast morphology, growth curve, population doubling time, cloning efficiency, marker gene expression pattern, cell cycle distribution and anchorage-dependent growth property of the primary cells. These data suggest that the new method established is useful for generating pig cell lines without viral sequence and antibiotic resistant gene.
EVALUATION OF THE EFFECTS OF ENVIRONMENTAL COMPOUNDS ON STEROID HORMONE PRODUCTION IN H295R CELLS

EPA Science Inventory

H295R cells constitute a pluripotent cell line that has retained the enzymatic ability to produce steroids along the entire steroidogenic pathway, including C19 androgens and C18 estrogens. For this reason, they have been a valued research tool, and have been employed in an ever...
l-Type Amino Acid Transporter-1 Overexpression and Melphalan Sensitivity in Barrett's Adenocarcinoma1

PubMed Central

Lin, Jules; Raoof, Duna A; Thomas, Dafydd G; Greenson, Joel K; Giordano, Thomas J; Robinson, Gregory S; Bourner, Maureen J; Bauer, Christopher T; Orringer, Mark B; Beer, David G

2004-01-01

Abstract The L-type amino acid transporter-1 (LAT-1) has been associated with tumor growth. Using cDNA microarrays, overexpression of LAT-1 was found in 87.5% (7/8) of esophageal adenocarcinomas relative to 12 Barrett's samples (33% metaplasia and 66% dysplasia) and was confirmed in 100% (28/28) of Barrett's adenocarcinomas by quantitative reverse transcription polymerase chain reaction. Immunohistochemistry revealed LAT-1 staining in 37.5% (24/64) of esophageal adenocarcinomas on tissue microarray. LAT-1 also transports the amino acid-related chemotherapeutic agent, melphalan. Two esophageal adenocarcinoma and one esophageal squamous cell line, expressing LAT-1 on Western blot analysis, were sensitive to therapeutic doses of melphalan (P < .001). Simultaneous treatment with the competitive inhibitor, BCH [2-aminobicyclo-(2,1,1)-heptane-2-carboxylic acid], decreased sensitivity to melphalan (P < .05). In addition, confluent esophageal squamous cultures were less sensitive to melphalan (P < .001) and had a decrease in LAT-1 protein expression. Tumors from two esophageal adenocarcinoma cell lines grown in nude mice retained LAT-1 mRNA expression. These results demonstrate that LAT-1 is highly expressed in a subset of esophageal adenocarcinomas and that Barrett's adenocarcinoma cell lines expressing LAT-1 are sensitive to melphalan. LAT-1 expression is also retained in cell lines grown in nude mice providing a model to evaluate melphalan as a chemotherapeutic agent against esophageal adenocarcinomas expressing LAT-1. PMID:15068672
Changes of heterogeneous cell populations in the Ishikawa cell line during long-term culture: Proposal for an in vitro clonal evolution model of tumor cells.

PubMed

Kasai, Fumio; Hirayama, Noriko; Ozawa, Midori; Iemura, Masashi; Kohara, Arihiro

2016-06-01

Genomic changes in tumor cell lines can occur during culture, leading to differences between cell lines carrying the same name. In this study, genome profiles between low and high passages were investigated in the Ishikawa 3-H-12 cell line (JCRB1505). Cells contained between 43 and 46 chromosomes and the modal number changed from 46 to 45 during culture. Cytogenetic analysis revealed that a translocation t(9;14), observed in all metaphases, is a robust marker for this cell line. Single-nucleotide polymorphism microarrays showed a heterogeneous copy number in the early passages and distinct profiles at late passages. These results demonstrate that cell culture can lead to elimination of ancestral clones by sequential selection, resulting in extensive replacement with a novel clone. Our observations on Ishikawa cells in vitro are different from the in vivo heterogeneity in which ancestral clones are often retained during tumor evolution and suggest a model for in vitro clonal evolution. Copyright © 2016 Elsevier Inc. All rights reserved.
Immortalized porcine mesenchymal cells derived from nasal mucosa, lungs, lymph nodes, spleen and bone marrow retain their stemness properties and trigger the expression of siglec-1 in co-cultured blood monocytic cells

PubMed Central

Garba, Abubakar; Desmarets, Lowiese M. B.; Acar, Delphine D.; Devriendt, Bert; Nauwynck, Hans J.

2017-01-01

Mesenchymal stromal cells have been isolated from different sources. They are multipotent cells capable of differentiating into many different cell types, including osteocytes, chondrocytes and adipocytes. They possess a therapeutic potential in the management of immune disorders and the repair of damaged tissues. Previous work in our laboratory showed an increase of the percentages of CD172a+, CD14+, CD163+, Siglec-1+, CD4+ and CD8+ hematopoietic cells, when co-cultured with immortalized mesenchymal cells derived from bone marrow. The present work aimed to demonstrate the stemness properties of SV40-immortalized mesenchymal cells derived from nasal mucosa, lungs, spleen, lymph nodes and red bone marrow and their immunomodulatory effect on blood monocytes. Mesenchymal cells from nasal mucosa, lungs, spleen, lymph nodes and red bone marrow were isolated and successfully immortalized using simian virus 40 large T antigen (SV40LT) and later, co-cultured with blood monocytes, in order to examine their differentiation stage (expression of Siglec-1). Flow cytometric analysis revealed that the five mesenchymal cell lines were positive for mesenchymal cell markers CD105, CD44, CD90 and CD29, but lacked the expression of myeloid cell markers CD16 and CD11b. Growth analysis of the cells demonstrated that bone marrow derived-mesenchymal cells proliferated faster compared with those derived from the other tissues. All five mesenchymal cell lines co-cultured with blood monocytes for 1, 2 and 7 days triggered the expression of siglec-1 in the monocytes. In contrast, no siglec-1+ cells were observed in monocyte cultures without mesenchymal cell lines. Mesenchymal cells isolated from nasal mucosa, lungs, spleen, lymph nodes and bone marrow were successfully immortalized and these cell lines retained their stemness properties and displayed immunomodulatory effects on blood monocytes. PMID:29036224
Immortalized porcine mesenchymal cells derived from nasal mucosa, lungs, lymph nodes, spleen and bone marrow retain their stemness properties and trigger the expression of siglec-1 in co-cultured blood monocytic cells.

PubMed

Garba, Abubakar; Desmarets, Lowiese M B; Acar, Delphine D; Devriendt, Bert; Nauwynck, Hans J

2017-01-01

Mesenchymal stromal cells have been isolated from different sources. They are multipotent cells capable of differentiating into many different cell types, including osteocytes, chondrocytes and adipocytes. They possess a therapeutic potential in the management of immune disorders and the repair of damaged tissues. Previous work in our laboratory showed an increase of the percentages of CD172a+, CD14+, CD163+, Siglec-1+, CD4+ and CD8+ hematopoietic cells, when co-cultured with immortalized mesenchymal cells derived from bone marrow. The present work aimed to demonstrate the stemness properties of SV40-immortalized mesenchymal cells derived from nasal mucosa, lungs, spleen, lymph nodes and red bone marrow and their immunomodulatory effect on blood monocytes. Mesenchymal cells from nasal mucosa, lungs, spleen, lymph nodes and red bone marrow were isolated and successfully immortalized using simian virus 40 large T antigen (SV40LT) and later, co-cultured with blood monocytes, in order to examine their differentiation stage (expression of Siglec-1). Flow cytometric analysis revealed that the five mesenchymal cell lines were positive for mesenchymal cell markers CD105, CD44, CD90 and CD29, but lacked the expression of myeloid cell markers CD16 and CD11b. Growth analysis of the cells demonstrated that bone marrow derived-mesenchymal cells proliferated faster compared with those derived from the other tissues. All five mesenchymal cell lines co-cultured with blood monocytes for 1, 2 and 7 days triggered the expression of siglec-1 in the monocytes. In contrast, no siglec-1+ cells were observed in monocyte cultures without mesenchymal cell lines. Mesenchymal cells isolated from nasal mucosa, lungs, spleen, lymph nodes and bone marrow were successfully immortalized and these cell lines retained their stemness properties and displayed immunomodulatory effects on blood monocytes.
Irradiated KHYG-1 retains cytotoxicity: potential for adoptive immunotherapy with a natural killer cell line.

PubMed

Suck, G; Branch, D R; Keating, A

2006-05-01

To evaluate gamma-irradiation on KHYG-1, a highly cytotoxic natural killer (NK) cell line and potential candidate for cancer immunotherapy. The NK cell line KHYG-1 was irradiated at 1 gray (Gy) to 50 Gy with gamma-irradiation, and evaluated for cell proliferation, cell survival, and cytotoxicity against tumor targets. We showed that a dose of at least 10 Gy was sufficient to inhibit proliferation of KHYG-1 within the first day but not its cytolytic activity. While 50 Gy had an apoptotic effect in the first hours after irradiation, the killing of K562 and HL60 targets was not different from non-irradiated cells but was reduced for the Ph + myeloid leukemia lines, EM-2 and EM-3. gamma-irradiation (at least 10 Gy) of KHYG-1 inhibits cell proliferation but does not diminish its enhanced cytolytic activity against several tumor targets. This study suggests that KHYG-1 may be a feasible immunotherapeutic agent in the treatment of cancers.
Development and characterization of an embryonic cell line from endangered endemic cyprinid Honmoroko Gnathopogon caerulescens (Sauvage, 1883).

PubMed

Higaki, Shogo; Shimada, Manami; Koyama, Yoshie; Fujioka, Yasuhiro; Sakai, Noriyoshi; Takada, Tatsuyuki

2015-09-01

Establishing a cell line from endemic species facilitates the cell biological research of these species in the laboratory. In this study, an epithelium-like cell line RME1 was established from the blastula-stage embryos of the critically endangered cyprinid Honmoroko Gnathopogon caerulescens, which is endemic to ancient Lake Biwa in Japan. To the best of our knowledge, this is the first embryonic cell line from an endangered fish species. This cell line is well adapted to grow at 28°C in the culture medium, which was successfully used for establishing testicular and ovarian cell lines of G. caerulescens, and has displayed stable growth over 60 passages since its initiation in June 2011. Although RME1 did not express the genes detected in blastula-stage embryos, such as oct4, sox2, nanog, and klf4, it showed a high euploidy rate (2n = 50; 67.2%) with normal diploid karyotype morphology, suggesting that RME1 retains the genomic organization of G. caerulescens and can prove to be a useful tool to investigate the unique properties of endangered endemic fishes at cellular level.
Retained sensitivity to cytotoxic pyrimidine nucleoside analogs in thymidine kinase 2 deficient human fibroblasts.

PubMed

Bjerke, Mia; Solaroli, Nicola; Lesko, Nicole; Balzarini, Jan; Johansson, Magnus; Karlsson, Anna

2010-01-01

Thymidine kinase 2 (TK2) is a mitochondrial deoxyribonucleoside kinase that phosphorylates several nucleoside analogs used in anti-viral and anti-cancer therapy. A fibroblast cell line with decreased TK2 activity was investigated in order to obtain insights in the effects of TK2 deficiency on nucleotide metabolism. The role of TK2 for the sensitivity against cytotoxic nucleoside analogs was also investigated. The TK2 deficient cells retained their sensitivity against all pyrimidine nucleoside analogs tested. This study suggests that nucleoside analog phosphorylation mediated by TK2 may be less important, compared to other deoxyribonucleoside kinases, for the cytotoxic effects of these compounds.
A block in lineage differentiation of immortal human mammary stem / progenitor cells by ectopically-expressed oncogenes

PubMed Central

Zhao, Xiangshan; Malhotra, Gautam K.; Band, Hamid; Band, Vimla

2011-01-01

Introduction: Emerging evidence suggests a direct role of cancer stem cells (CSCs) in the development of breast cancer. In vitro cellular models that recapitulate properties of CSCs are therefore highly desirable. We have previously shown that normal human mammary epithelial cells (hMECs) immortalized with human telomerase reverse transcriptase (hTERT) possess properties of mammary stem / progenitor cells. Materials and Methods: In the present study, we used this cell system to test the idea that other known hMEC-immortalizing oncogenes (RhoA, HPVE6, HPVE7, p53 mutant, and treatment with γ-radiation), share with hTERT, the ability to maintain mammary stem / progenitor cells. Results: The results presented here demonstrate that similar to hMECs immortalized with hTERT, all hMEC cell lines immortalized using various oncogenic strategies express stem / progenitor cell markers. Furthermore, analyses using 2D and 3D culture assays demonstrate that all the immortal cell lines retain their ability to self-renew and to differentiate along the luminal lineage. Remarkably, the stem / progenitor cell lines generated using various oncogenic strategies exhibit a block in differentiation along the myoepithelial lineage, a trait that is retained on hTERT-immortalized stem / progenitors. The inability to differentiate along the myoepithelial lineage could be induced by ectopic mutant p53 expression in hTERT-immortalized hMEC. Conclusions: Our studies demonstrate that stem / progenitor cell characteristics of hMECs are maintained upon immortalization by using various cancer-relevant oncogenic strategies. Oncogene-immortalized hMECs show a block in their ability to differentiate along the myoepithelial lineage. Abrogation of the myoepithelial differentiation potential by a number of distinct oncogenic insults suggests a potential explanation for the predominance of luminal and rarity of myoepithelial breast cancers. PMID:22279424
A block in lineage differentiation of immortal human mammary stem / progenitor cells by ectopically-expressed oncogenes.

PubMed

Zhao, Xiangshan; Malhotra, Gautam K; Band, Hamid; Band, Vimla

2011-01-01

Emerging evidence suggests a direct role of cancer stem cells (CSCs) in the development of breast cancer. In vitro cellular models that recapitulate properties of CSCs are therefore highly desirable. We have previously shown that normal human mammary epithelial cells (hMECs) immortalized with human telomerase reverse transcriptase (hTERT) possess properties of mammary stem / progenitor cells. In the present study, we used this cell system to test the idea that other known hMEC-immortalizing oncogenes (RhoA, HPVE6, HPVE7, p53 mutant, and treatment with γ-radiation), share with hTERT, the ability to maintain mammary stem / progenitor cells. The results presented here demonstrate that similar to hMECs immortalized with hTERT, all hMEC cell lines immortalized using various oncogenic strategies express stem / progenitor cell markers. Furthermore, analyses using 2D and 3D culture assays demonstrate that all the immortal cell lines retain their ability to self-renew and to differentiate along the luminal lineage. Remarkably, the stem / progenitor cell lines generated using various oncogenic strategies exhibit a block in differentiation along the myoepithelial lineage, a trait that is retained on hTERT-immortalized stem / progenitors. The inability to differentiate along the myoepithelial lineage could be induced by ectopic mutant p53 expression in hTERT-immortalized hMEC. Our studies demonstrate that stem / progenitor cell characteristics of hMECs are maintained upon immortalization by using various cancer-relevant oncogenic strategies. Oncogene-immortalized hMECs show a block in their ability to differentiate along the myoepithelial lineage. Abrogation of the myoepithelial differentiation potential by a number of distinct oncogenic insults suggests a potential explanation for the predominance of luminal and rarity of myoepithelial breast cancers.
Odontoblast-Like Cells Differentiated from Dental Pulp Stem Cells Retain Their Phenotype after Subcultivation

PubMed Central

Baldión, Paula A.; Velandia-Romero, Myriam L.

2018-01-01

Odontoblasts, the main cell type in teeth pulp tissue, are not cultivable and they are responsible for the first line of response after dental restauration. Studies on dental materials cytotoxicity and odontoblast cells physiology require large quantity of homogenous cells retaining most of the phenotype characteristics. Odontoblast-like cells (OLC) were differentiated from human dental pulp stem cells using differentiation medium (containing TGF-β1), and OLC expanded after trypsinization (EXP-21) were evaluated and compared. Despite a slower cell growth curve, EXP-21 cells express similarly the odontoblast markers dentinal sialophosphoprotein and dentin matrix protein-1 concomitantly with RUNX2 transcripts and low alkaline phosphatase activity as expected. Both OLC and EXP-21 cells showed similar mineral deposition activity evidenced by alizarin red and von Kossa staining. These results pointed out minor changes in phenotype of subcultured EXP-21 regarding the primarily differentiated OLC, making the subcultivation of these cells a useful strategy to obtain odontoblasts for biocompatibility or cell physiology studies in dentistry. PMID:29670655
The Chlamydial Inclusion Preferentially Intercepts Basolaterally Directed Sphingomyelin-Containing Exocytic Vacuoles

PubMed Central

Moore, Elizabeth R.; Fischer, Elizabeth R.; Mead, David J.; Hackstadt, Ted

2010-01-01

Chlamydiae replicate intracellularly within a unique vacuole termed the inclusion. The inclusion circumvents classical endosomal/lysosomal pathways but actively intercepts a subset of Golgi-derived exocytic vesicles containing sphingomyelin (SM) and cholesterol. To further examine this interaction, we developed a polarized epithelial cell model to study vectoral trafficking of lipids and proteins to the inclusion. We examined seven epithelial cell lines for their ability to form single monolayers of polarized cells and support chlamydial development. Of these cell lines, polarized colonic mucosal C2BBe1 cells were readily infected with Chlamydia trachomatis and remained polarized throughout infection. Trafficking of (6-((N-(7-nitrobenz-2-oxa-1, 3-diazol-4-yl) amino)hexanoyl)sphingosine) (NBD-C6-ceramide) and its metabolic derivatives, NBD-glucosylceramide (GlcCer) and NBD-SM, was analyzed. SM was retained within L2-infected cells relative to mock-infected cells, correlating with a disruption of basolateral SM trafficking. There was no net retention of GlcCer within L2-infected cells and purification of C. trachomatis elementary bodies from polarized C2BBe1 cells confirmed that bacteria retained only SM. The chlamydial inclusion thus appears to preferentially intercept basolaterally-directed SM-containing exocytic vesicles, suggesting a divergence in SM and GlcCer trafficking. The observed changes in lipid trafficking were a chlamydia-specific effect because Coxiella burnetii-infected cells revealed no changes in GlcCer or SM polarized trafficking. PMID:18778406
Spontaneous pyrogen production by mouse histiocytic and myelomonocytic tumor cell lines in vitro.

PubMed

Bodel, P

1978-05-01

Tumor-associated fever occurs commonly in acute leukemias and lymphomas. We investigated the capacity for in vitro production of pyrogen by three mouse histiocytic lymphoma cell lines (J-774, PU5-1.8, p 388 D1), one myelomonoyctic line (WEHI-3), and tow lymphoma-derived lines, RAW-8 and R-8. Pyrogen was released spontaneously into the culture medium during growth by all cell lines with macrophage or myeloid characteristics including lysozyme production; R-8 cells, of presumed B-lymphocyte origin, did not produce pyrogen. When injected into mice, the pyrogens gave fever curves typical of endogenous pyrogen, were inactived by heating to 56 degrees C and by pronase digestion, and appeared to be secreted continuously by viable cells. Two pyrogenic molecular species produced by H-774 cells were identified by Sephadex filtration, one of mol wt approximately equal to 30,000, and the other greater than or equal to 60,000. By contrast, three carcinoma cell lines of human origin and SV-40 3T3 mouse fibroblasts did not produce pyrogen in vitro. These results suggest that some malignant cells derived from phagocytic cells of bone marrow origin retain their capacity for pyrogen production, and may spontaneously secrete pyrogen during growth.
Conjoined Cochlear Models:. the Twamp and the Sandwich

NASA Astrophysics Data System (ADS)

Hubbard, Allyn

2009-02-01

A new model of the cochlea is created by joining parts of the traveling-wave amplifier (TWAMP) and the Sandwich models. The lossy, untuned traveling-wave line of the TWAMP is retained, but the TWAMP's tuned traveling-wave line is replaced by the Sandwich's traveling-wave line that represents the reticular lamina (RL) and scala tympani. The model combines stereocilliary forces, which act between the tectorial membrane (TM) and RL, with somatic outer hair cell forces that power the Sandwich.
Characteristics of a cell line established from a patient with multiple osteosarcoma, appearing 13 years after treatment for bilateral retinoblastoma.

PubMed

Fodstad, O; Brøgger, A; Bruland, O; Solheim, O P; Nesland, J M; Pihl, A

1986-07-15

An osteosarcoma cell line, OHS, was established from a patient with multiple skeletal manifestations of osteosarcoma, developing after bilateral retinoblastoma. The tumor cells expressed sarcoma-associated antigens and showed rapid growth in monolayers and as multicellular spheroids. They formed distinct colonies in soft agar, and subcutaneous tumors in nude mice. Morphological studies indicated that OHS cells had retained important characteristics of the cells of origin. No deletion of the retinoblastoma genes on chromosome 13q14 could be demonstrated with the banding techniques used. However, cytogenetic studies revealed double minute chromosomes, as evidence of gene amplification, as well as translocations involving chromosomes 1,6,11 and 13. The OHS line can be used to study the genetic basis of tumor initiation and growth, and to elucidate factors predisposing for second primary cancers in retinoblastoma patients.

Characterization and differentiation of human embryonic stem cells.

PubMed

Carpenter, M K; Rosler, E; Rao, M S

2003-01-01

Cell replacement therapies have been limited by the availability of sufficient quantities of cells for transplantation. Human ES (hES) cell lines have recently been generated by several laboratories. When maintained for over 1 year in vitro, they remain karyotypically and phenotypically stable and may therefore provide an excellent source material for cell therapies. Currently, data is available for 26 hES cell lines. Although limited characterization has been performed on most of these lines, there are remarkable similarities in expression of markers. hES cell lines derived in different laboratories show similar expression profiles of surface markers, including SSEA-4, Tra-1-60, and Tra-1-81. In addition, markers associated with pluripotent cells such as OCT-4 are expressed at in all cell lines tested. These cells express high levels of telomerase and appear to have indefinite growth potential. The generation of the large quantities of cells necessary for cell replacement therapies will require a cell population which is stable over long term culture. We have characterized the properties of multiple hES cell lines that have been maintained in culture for extended periods. Quantitative analyses demonstrate that all of the cell lines examined show consistent marker expression and retain a normal karyotype after long-term culture. hES cells have been differentiated into the derivatives of all three germ layers. Specifically this includes cardiomyocytes, neural cells, hepatocyte-like cells, endothelial cells and hematopoietic progenitor cells. These data demonstrating the karyotypic and phenotypic stability of hES cells and their extensive differentiative capacity indicate that they may be an appropriate source of cells for multiple regenerative medicine applications.
Establishment of mammary gland model in vitro: culture and evaluation of a yak mammary epithelial cell line.

PubMed

Fu, Mei; Chen, Yabing; Xiong, Xianrong; Lan, Daoliang; Li, Jian

2014-01-01

This study aimed to establish yak mammary epithelial cells (YMECs) for an in vitro model of yak mammary gland biology. The primary culture of YMECs was obtained from mammary gland tissues of lactating yak and then characterized using immunocytochemistry, RT-PCR, and western blot analysis. Whether foreign genes could be transfected into the YMECs were examined by transfecting the EGFP gene into the cells. Finally, the effect of Staphylococcus aureus infection on YMECs was determined. The established YMECs retained the mammary epithelial cell characteristics. A spontaneously immortalized yak mammary epithelial cell line was established and could be continuously subcultured for more than 60 passages without senescence. The EGFP gene was successfully transferred into the YMECs, and the transfected cells could be maintained for a long duration in the culture by continuous subculturing. The cells expressed more antimicrobial peptides upon S.aureus invasion. Therefore, the established cell line could be considered a model system to understand yak mammary gland biology.
[The characters and specific features of new human embryonic stem cells lines].

PubMed

Krylova, T A; Kol'tsova, A M; Zenin, V V; Gordeeva, O F; Musorina, A S; Goriachaia, T S; Shlykova, S A; Kamenetskaia, Iu K; Pinaev, G P; Polianskaia, G G

2009-01-01

Four continuous human embryonic stem cell lines (SC1, SC2, SC3 and SC4), derived from the blastocysts has been described. The cell lines were cultivated on mitotically inactivated human feeder cells. The cell lines SC1 and SC2 have passed through 150 population doublings and the cell lines SC3 and SC4 -- near 120 populations doublings, which exceeds Hayflick limit sufficiently. These cell lines maintain high activity of alkaline phosphatase, expression of transcription factor OCT-4 and cell surface antigens (SSEA-4, TRA-1-60 and TRA-1-81), confirming their ESC status and human specificity. Immunofluorescent detection of antigens, characteristic of ectoderm, endoderm and mesoderm confirms the ability of these cells to retain their pluripotency under in vitro condition. PCR analysis revealed expression of six genes specific for pluripotent cells (OCT-4, NANOG, DPPA3/STELLA, TDGF/CRIPTO and LEFTYA). Correlation between the level of proliferative activity and the character of DNA-bound fluorescent staining was found. Fluorescent dyes, Hoechst 33342 and PI, produced diffuse staining of the nuclei in slowly proliferating cells of the SC1 and SC2 lines. In contrast, in actively proliferating cells of the SC3 and SC4 lines, the clear staining of the nuclei was observed. Upon changing the cultivation condition, proliferative activity of SC3 and SC4 lines decreased and became similar to that of SC1 and SC2 lines. The character of the fluorescent staining of all these lines was also shown to be similar. These results show that quality of the fluorescent staining with Hoechst 33342 and PI reflects the level of proliferation. Possible causes and mechanisms of this feature of human ESC are discussed.
Generation and Characterization of an Immortalized Human Esophageal Myofibroblast Line.

PubMed

Niu, Chao; Chauhan, Uday; Gargus, Matthew; Shaker, Anisa

2016-01-01

Stromal cells with a myofibroblast phenotype present in the normal human esophagus are increased in individuals with gastro-esophageal reflux disease (GERD). We have previously demonstrated that myofibroblasts stimulated with acid and TLR4 agonists increase IL-6 and IL-8 secretion using primary cultures of myofibroblasts established from normal human esophagus. While primary cultures have the advantage of reflecting the in vivo environment, a short life span and unavoidable heterogeneity limits the usefulness of this model in larger scale in vitro cellular signaling studies. The major aim of this paper therefore was to generate a human esophageal myofibroblast line with an extended lifespan. In the work presented here we have generated and characterized an immortalized human esophageal myofibroblast line by transfection with a commercially available GFP-hTERT lentivirus. Immortalized human esophageal myofibroblasts demonstrate phenotypic, genotypic and functional similarity to primary cultures of esophageal myofibroblasts we have previously described. We found that immortalized esophageal myofibroblasts retain myofibroblast spindle-shaped morphology at low and high confluence beyond passage 80, and express α-SMA, vimentin, and CD90 myofibroblast markers. Immortalized human esophageal myofibroblasts also express the putative acid receptor TRPV1 and TLR4 and retain the functional capacity to respond to stimuli encountered in GERD with secretion of IL-6. Finally, immortalized human esophageal myofibroblasts also support the stratified growth of squamous esophageal epithelial cells in 3D organotypic cultures. This newly characterized immortalized human esophageal myofibroblast cell line can be used in future cellular signaling and co-culture studies.
Cytokeratin characterization of human prostatic carcinoma and its derived cell lines.

PubMed

Nagle, R B; Ahmann, F R; McDaniel, K M; Paquin, M L; Clark, V A; Celniker, A

1987-01-01

Two murine monoclonal anti-cytokeratin antibodies with defined specificity were shown to distinguish between basal cells and luminal cells in human prostate tissue. Forty-one biopsies or transurethral resection specimens were characterized using these two antibodies. In cases of benign prostatic hyperplasia, focal loss of the basal cell layer was noted in areas of glandular proliferation. Ten cases of adenocarcinoma of the prostate, varying in Gleason's histological grade from 2 to 4, were also studied. In each case the carcinoma was shown to represent the luminal cell phenotype with no evidence of involvement of the basal cell phenotype. An analysis of three established metastatic prostatic carcinoma cell lines (DU-145, PC-3, and LNCaP) using two-dimensional electrophoresis showed that the cytokeratin complement of each cell line was slightly different but retained the phenotype of the luminal cell. It was concluded that during both hyperplasia and neoplastic transformation of the prostate, the luminal cell phenotype is primarily involved and that the basal cell phenotype does not appear to contribute to either intraluminal proliferation or invasive cell populations.
Cellular localization of the activated EGFR determines its effect on cell growth in MDA-MB-468 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hyatt, Dustin C.; Ceresa, Brian P.

2008-11-01

The epidermal growth factor (EGF) receptor (EGFR) is a ubiquitously expressed receptor tyrosine kinase that regulates diverse cell functions that are dependent upon cell type, the presence of downstream effectors, and receptor density. In addition to activating biochemical pathways, ligand stimulation causes the EGFR to enter the cell via clathrin-coated pits. Endocytic trafficking influences receptor signaling by controlling the duration of EGFR phosphorylation and coordinating the receptor's association with downstream effectors. To better understand the individual contributions of cell surface and cytosolic EGFRs on cell physiology, we used EGF that was conjugated to 900 nm polystyrene beads (EGF-beads). EGF-beads canmore » stimulate the EGFR and retain the activated receptor at the plasma membrane. In MDA-MB-468 cells, a breast cancer cell line that over-expresses the EGFR, only internalized, activated EGFRs stimulate caspase-3 and induce cell death. Conversely, signaling cascades triggered from activated EGFR retained at the cell surface inhibit caspase-3 and promote cell proliferation. Thus, through endocytosis, the activated EGFR can differentially regulate cell growth in MDA-MB-468 cells.« less
Isolation, purification, culture and characterisation of myoepithelial cells from normal and neoplastic canine mammary glands using a magnetic-activated cell sorting separation system.

PubMed

Sánchez-Céspedes, R; Maniscalco, L; Iussich, S; Martignani, E; Guil-Luna, S; De Maria, R; Martín de Las Mulas, J; Millán, Y

2013-08-01

Mammary gland tumours, the most common malignant neoplasm in bitches, often display myoepithelial (ME) cell proliferation. The aim of this study was to isolate, purify, culture and characterise ME cells from normal and neoplastic canine mammary glands. Monodispersed cells from three normal canine mammary glands and five canine mammary tumours were incubated with an anti-Thy1 antibody and isolated by magnetic-activated cell sorting (MACS). Cells isolated from two normal glands (cell lines CmME-N1 and CmME-N2) and four tumours (cell lines CmME-K1 from a complex carcinoma, CmME-K2 from a simple tubulopapillary carcinoma, and CmME-K3 and CmME-K4 from two carcinomas within benign tumours) were cultured in supplemented DMEM/F12 media for 40days. Cell purity was >90%. Tumour-derived ME cell lines exhibited heterogeneous morphology, growth patterns and immunocytochemical expression of cytokeratins, whereas cell lines from normal glands retained their morphology and levels of cytokeratin expression during culture. Cell lines from normal glands and carcinomas within benign tumours grew more slowly than those from simple and complex carcinomas. This methodology has the potential to be used for in vitro analysis of the role of ME cells in the growth and progression of canine mammary tumours. Copyright © 2013 Elsevier Ltd. All rights reserved.
Doxorubicin-anti-carcinoembryonic antigen immunoconjugate activity in vitro.

PubMed

Richardson, V J; Ford, C H; Tsaltas, G; Gallant, M E

1989-04-01

An in vitro model consisting of a series of 11 human cancer cell lines with varying density of expression of membrane carcinoembryonic antigen (CEA) has been used to evaluate conjugates of doxorubicin (Adriamycin) covalently linked by a carbodiimide method to goat polyclonal antibodies and mouse monoclonal antibodies to CEA. Conjugates were produced which retained both antigen binding and drug cytotoxicity. IC50 values were determined for free drug, free drug mixed with unconjugated antibodies and for the immunoconjugates. Cell lines that were very sensitive to free drug (IC50 less than 100 ng/ml) were also found to be highly sensitive to conjugated drug and similarly cell lines resistant to drug (IC50 greater than 1,000 ng/ml) were also resistant to conjugated drug. Although there was no correlation between CEA expression and conjugates efficacy, competitive inhibition studies using autologous antibody to block conjugate binding to cells indicated immunoconjugates specificity for the CEA target.
Establishment of a non-tumorigenic papillary thyroid cell line (FB-2) carrying the RET/PTC1 rearrangement.

PubMed

Basolo, Fulvio; Giannini, Riccardo; Toniolo, Antonio; Casalone, Rosario; Nikiforova, Marina; Pacini, Furio; Elisei, Rossella; Miccoli, Paolo; Berti, Piero; Faviana, Pinuccia; Fiore, Lisa; Monaco, Carmen; Pierantoni, Giovanna Maria; Fedele, Monica; Nikiforov, Yuri E; Santoro, Massimo; Fusco, Alfredo

2002-02-10

A novel human thyroid papillary carcinoma cell line (FB-2) has been established and characterized. FB-2 cells harbor the RET/PTC1 chimeric oncogene in which the RET kinase domain is fused to the H4 gene. FB-2 cells neither formed colonies in semisolid media nor induced tumors after heterotransplant into severe combined immunodeficient mice. However, HMGI(Y), HMGI-C and c-myc genes, which are associated to thyroid cell transformation, were abundantly expressed in FB-2 cells but not in normal thyroid cells. FB-2 cells only partially retained the differentiated thyroid phenotype. In fact, the PAX-8 gene, which codes for a transcriptional factor required for thyroid cell differentiation, was expressed, while thyroglobulin, TSH-receptor and thyroperoxidase genes were not. Moreover, FB-2 cells produced high levels of interleukin (IL)-6 and IL-8. Copyright 2001 Wiley-Liss, Inc.
Establishment and Characterization of a Testicular Cell Line from the Half-Smooth Tongue Sole, Cynoglossus semilaevis

PubMed Central

Zhang, Bo; Wang, Xianli; Sha, Zhenxia; Yang, Changgeng; Liu, Shanshan; Wang, Na; Chen, Song-Lin

2011-01-01

Spermatogenesis within the adult testis is an excellent system for studying stem cell renewal and differentiation, which is under the control of testicular somatic cells. In order to understanding spermatogenesis in the half-smooth tongue sole (Cynoglossus semilaevis) as a marine fish model of aquaculture importance, we established a cell line called CSGC from a juvenile gonad of this organism. CSGC is composed of fibroblast-like cells, retains a diploid karyotype of 42 chromosomes, lacks the heterogametic W chromosome, lacks a female specific marker and expresses the dmrt, a marker for testicular somatic cells. Therefore, CSGC appears to consist of testicular somatic cell cells. We show that this cell line is effective for infection by the turbot reddish body iridovirus and flounder lymphocystis disease virus as evidenced by the appearance of cytopathic effect and virus propagation in the virus-infected cells, and most convincingly, the observation of viral particles by electon microscopy, demonstrateing that CSGC is suitable to study interactions between virus and host cells. As a first fish testicular somatic cell line of the ZZ-ZW genetic sex determination system, CSGC will be a useful tool to study sex-related events and interactions between somatic cells and germ cells during spermatogenesis. PMID:21547062
Wild-Type U2AF1 Antagonizes the Splicing Program Characteristic of U2AF1-Mutant Tumors and Is Required for Cell Survival

PubMed Central

Fei, Dennis Liang; Motowski, Hayley; Chatrikhi, Rakesh; Gao, Shaojian; Kielkopf, Clara L.; Varmus, Harold

2016-01-01

We have asked how the common S34F mutation in the splicing factor U2AF1 regulates alternative splicing in lung cancer, and why wild-type U2AF1 is retained in cancers with this mutation. A human lung epithelial cell line was genetically modified so that U2AF1S34F is expressed from one of the two endogenous U2AF1 loci. By altering levels of mutant or wild-type U2AF1 in this cell line and by analyzing published data on human lung adenocarcinomas, we show that S34F-associated changes in alternative splicing are proportional to the ratio of S34F:wild-type gene products and not to absolute levels of either the mutant or wild-type factor. Preferential recognition of specific 3′ splice sites in S34F-expressing cells is largely explained by differential in vitro RNA-binding affinities of mutant versus wild-type U2AF1 for those same 3′ splice sites. Finally, we show that lung adenocarcinoma cell lines bearing U2AF1 mutations do not require the mutant protein for growth in vitro or in vivo. In contrast, wild-type U2AF1 is required for survival, regardless of whether cells carry the U2AF1S34F allele. Our results provide mechanistic explanations of the magnitude of splicing changes observed in U2AF1-mutant cells and why tumors harboring U2AF1 mutations always retain an expressed copy of the wild-type allele. PMID:27776121
Reliable generation of induced pluripotent stem cells from human lymphoblastoid cell lines.

PubMed

Barrett, Robert; Ornelas, Loren; Yeager, Nicole; Mandefro, Berhan; Sahabian, Anais; Lenaeus, Lindsay; Targan, Stephan R; Svendsen, Clive N; Sareen, Dhruv

2014-12-01

Patient-specific induced pluripotent stem cells (iPSCs) hold great promise for many applications, including disease modeling to elucidate mechanisms involved in disease pathogenesis, drug screening, and ultimately regenerative medicine therapies. A frequently used starting source of cells for reprogramming has been dermal fibroblasts isolated from skin biopsies. However, numerous repositories containing lymphoblastoid cell lines (LCLs) generated from a wide array of patients also exist in abundance. To date, this rich bioresource has been severely underused for iPSC generation. We first attempted to create iPSCs from LCLs using two existing methods but were unsuccessful. Here we report a new and more reliable method for LCL reprogramming using episomal plasmids expressing pluripotency factors and p53 shRNA in combination with small molecules. The LCL-derived iPSCs (LCL-iPSCs) exhibited identical characteristics to fibroblast-derived iPSCs (fib-iPSCs), wherein they retained their genotype, exhibited a normal pluripotency profile, and readily differentiated into all three germ-layer cell types. As expected, they also maintained rearrangement of the heavy chain immunoglobulin locus. Importantly, we also show efficient iPSC generation from LCLs of patients with spinal muscular atrophy and inflammatory bowel disease. These LCL-iPSCs retained the disease mutation and could differentiate into neurons, spinal motor neurons, and intestinal organoids, all of which were virtually indistinguishable from differentiated cells derived from fib-iPSCs. This method for reliably deriving iPSCs from patient LCLs paves the way for using invaluable worldwide LCL repositories to generate new human iPSC lines, thus providing an enormous bioresource for disease modeling, drug discovery, and regenerative medicine applications. ©AlphaMed Press.
Immortalization of chicken preadipocytes by retroviral transduction of chicken TERT and TR

PubMed Central

Wang, Wei; Zhang, Tianmu; Wu, Chunyan; Wang, Shanshan; Wang, Yuxiang; Wang, Ning

2017-01-01

The chicken is an important agricultural animal and model for developmental biology, immunology and virology. Excess fat accumulation continues to be a serious problem for the chicken industry. However, chicken adipogenesis and obesity have not been well investigated, because no chicken preadipocyte cell lines have been generated thus far. Here, we successfully generated two immortalized chicken preadipocyte cell lines through transduction of either chicken telomerase reverse transcriptase (chTERT) alone or in combination with chicken telomerase RNA (chTR). Both of these cell lines have survived >100 population doublings in vitro, display high telomerase activity and have no sign of replicative senescence. Similar to primary chicken preadipocytes, these two cell lines display a fibroblast-like morphology, retain the capacity to differentiate into adipocytes, and do not display any signs of malignant transformation. Isoenzyme analysis and PCR-based analysis confirmed that these two cell lines are of chicken origin and are free from inter-species contamination. To our knowledge, this is the first report demonstrating the generation of immortal chicken cells by introduction of chTERT and chTR. Our established chicken preadipocyte cell lines show great promise as an in vitro model for the investigation of chicken adipogenesis, lipid metabolism, and obesity and its related diseases, and our results also provide clues for immortalizing other avian cell types. PMID:28486516
Establishment and characterization of a normal melanocyte cell line derived from pig skin.

PubMed

Julé, Sophia; Bossé, Philippe; Egidy, Giorgia; Panthier, Jean-Jacques

2003-08-01

Several minipig strains develop spontaneous malignant melanoma. As a first step toward the analysis of genes involved in the tumoral progression of melanoma in these animal models, we developed culture conditions for pig melanocytes whereby melanocytes from normal epidermis can be isolated directly onto mitotically inactivated keratinocytes in Eagle's minimal essential medium supplemented with fetal calf serum, tetradecanoyl phorbol acetate (TPA) and cholera toxin. We also derived an immortal line of pigmented melanocytes from the epidermis of a healthy Meishan pig. This cell line, designated PigMel, retains differentiation function in culture, dependence on TPA and cholera toxin and a diploid chromosome number. PigMel melanocytes exhibit morphological and molecular characteristics common to normal mammalian skin melanocytes.
Development and Characterisation of a Human Chronic Skin Wound Cell Line-Towards an Alternative for Animal Experimentation.

PubMed

Caley, Matthew; Wall, Ivan B; Peake, Matthew; Kipling, David; Giles, Peter; Thomas, David W; Stephens, Phil

2018-03-27

Background : Chronic skin wounds are a growing financial burden for healthcare providers, causing discomfort/immobility to patients. Whilst animal chronic wound models have been developed to allow for mechanistic studies and to develop/test potential therapies, such systems are not good representations of the human chronic wound state. As an alternative, human chronic wound fibroblasts (CWFs) have permitted an insight into the dysfunctional cellular mechanisms that are associated with these wounds. However, such cells strains have a limited replicative lifespan and therefore a limited reproducibility/usefulness. Objectives : To develop/characterise immortalised cell lines of CWF and patient-matched normal fibroblasts (NFs). Methods and Results : Immortalisation with human telomerase resulted in both CWF and NF proliferating well beyond their replicative senescence end-point (respective cell strains senesced as normal). Gene expression analysis demonstrated that, whilst proliferation-associated genes were up-regulated in the cell lines (as would be expected), the immortalisation process did not significantly affect the disease-specific genotype. Immortalised CWF (as compared to NF) also retained a distinct impairment in their wound repopulation potential (in line with CWF cell strains). Conclusions : These novel CWF cell lines are a credible animal alternative and could be a valuable research tool for understanding both the aetiology of chronic skin wounds and for therapeutic pre-screening.
Development and characterization of a mouse floxed Bmp2 osteoblast cell line that retains osteoblast genotype and phenotype

PubMed Central

Wu, Li-an; Feng, Junsheng; Wang, Lynn; Mu, Yan-dong; Baker, Andrew; Donly, Kevin J.; Harris, Stephen E.; MacDougall, Mary; Chen, Shuo

2011-01-01

Bone morphogenetic protein 2 (Bmp2) is essential for osteoblast differentiation and osteogenesis. Generation of floxed Bmp2 osteoblast cell lines is a valuable tool for studying the effects of Bmp2 on osteoblast differentiation and its signaling pathways during skeletal metabolism. Due to relatively limited sources of primary osteoblasts, we have developed cell lines that serve as good surrogate models for the study of osteoblast cell differentiation and bone mineralization. In this study, we established and characterized immortalized mouse floxed Bmp2 osteoblast cell lines. Primary mouse floxed Bmp2 osteoblasts were transfected with pSV3-neo and clonally selected. These transfected cells were verified by PCR and immunohistochemistry. To determine the genotype and phenotype of the immortalized cells, cell morphology, proliferation, differentiation and mineralization were analyzed. Also, expression of osteoblast-related gene markers including Runx2, Osx, ATF4, Dlx3, bone sialoprotein, dentin matrix protein 1, osteonectin, osteocalcin and osteopontin were examined by quantitative RT-PCR and immunohistochemistry. These results showed that immortalized floxed Bmp2 osteoblasts had a higher proliferation rate but preserved their genotypic and phenotypic characteristics similar to the primary cells. Thus, we, for the first time, describe the development of immortalized mouse floxed Bmp2 osteoblast cell lines and present a useful model to study osteoblast biology mediated by BMP2 and its downstream signaling transduction pathways. PMID:21271257
Generation of stable PDX derived cell lines using conditional reprogramming.

PubMed

Borodovsky, Alexandra; McQuiston, Travis J; Stetson, Daniel; Ahmed, Ambar; Whitston, David; Zhang, Jingwen; Grondine, Michael; Lawson, Deborah; Challberg, Sharon S; Zinda, Michael; Pollok, Brian A; Dougherty, Brian A; D'Cruz, Celina M

2017-12-06

Efforts to develop effective cancer therapeutics have been hindered by a lack of clinically predictive preclinical models which recapitulate this complex disease. Patient derived xenograft (PDX) models have emerged as valuable tools for translational research but have several practical limitations including lack of sustained growth in vitro. In this study, we utilized Conditional Reprogramming (CR) cell technology- a novel cell culture system facilitating the generation of stable cultures from patient biopsies- to establish PDX-derived cell lines which maintain the characteristics of the parental PDX tumor. Human lung and ovarian PDX tumors were successfully propagated using CR technology to create stable explant cell lines (CR-PDX). These CR-PDX cell lines maintained parental driver mutations and allele frequency without clonal drift. Purified CR-PDX cell lines were amenable to high throughput chemosensitivity screening and in vitro genetic knockdown studies. Additionally, re-implanted CR-PDX cells proliferated to form tumors that retained the growth kinetics, histology, and drug responses of the parental PDX tumor. CR technology can be used to generate and expand stable cell lines from PDX tumors without compromising fundamental biological properties of the model. It offers the ability to expand PDX cells in vitro for subsequent 2D screening assays as well as for use in vivo to reduce variability, animal usage and study costs. The methods and data detailed here provide a platform to generate physiologically relevant and predictive preclinical models to enhance drug discovery efforts.
A CRISPR-Cas9 Generated MDCK Cell Line Expressing Human MDR1 Without Endogenous Canine MDR1 (cABCB1): An Improved Tool for Drug Efflux Studies.

PubMed

Karlgren, Maria; Simoff, Ivailo; Backlund, Maria; Wegler, Christine; Keiser, Markus; Handin, Niklas; Müller, Janett; Lundquist, Patrik; Jareborg, Anne-Christine; Oswald, Stefan; Artursson, Per

2017-09-01

Madin-Darby canine kidney (MDCK) II cells stably transfected with transport proteins are commonly used models for drug transport studies. However, endogenous expression of especially canine MDR1 (cMDR1) confounds the interpretation of such studies. Here we have established an MDCK cell line stably overexpressing the human MDR1 transporter (hMDR1; P-glycoprotein), and used CRISPR-Cas9 gene editing to knockout the endogenous cMDR1. Genomic screening revealed the generation of a clonal cell line homozygous for a 4-nucleotide deletion in the canine ABCB1 gene leading to a frameshift and a premature stop codon. Knockout of cMDR1 expression was verified by quantitative protein analysis and functional studies showing retained activity of the human MDR1 transporter. Application of this cell line allowed unbiased reclassification of drugs previously defined as both substrates and non-substrates in different studies using commonly used MDCK-MDR1 clones. Our new MDCK-hMDR1 cell line, together with a previously developed control cell line, both with identical deletions in the canine ABCB1 gene and lack of cMDR1 expression represent excellent in vitro tools for use in drug discovery. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.
The transcriptional diversity of 25 Drosophila cell lines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cherbas, Lucy; Willingham, Aarron; Zhang, Dayu

2010-12-22

Drosophila melanogaster cell lines are important resources for cell biologists. In this article, we catalog the expression of exons, genes, and unannotated transcriptional signals for 25 lines. Unannotated transcription is substantial (typically 19% of euchromatic signal). Conservatively, we identify 1405 novel transcribed regions; 684 of these appear to be new exons of neighboring, often distant, genes. Sixty-four percent of genes are expressed detectably in at least one line, but only 21% are detected in all lines. Each cell line expresses, on average, 5885 genes, including a common set of 3109. Expression levels vary over several orders of magnitude. Major signalingmore » pathways are well represented: most differentiation pathways are ‘‘off’’ and survival/growth pathways ‘‘on.’’ Roughly 50% of the genes expressed by each line are not part of the common set, and these show considerable individuality. Thirty-one percent are expressed at a higher level in at least one cell line than in any single developmental stage, suggesting that each line is enriched for genes characteristic of small sets of cells. Most remarkable is that imaginal disc-derived lines can generally be assigned, on the basis of expression, to small territories within developing discs. These mappings reveal unexpected stability of even fine-grained spatial determination. No two cell lines show identical transcription factor expression. We conclude that each line has retained features of an individual founder cell superimposed on a common ‘‘cell line‘‘ gene expression pattern. We report the transcriptional profiles of 25 Drosophila melanogaster cell lines, principally by whole-genome tiling microarray analysis of total RNA, carried out as part of the modENCODE project. The data produced in this study add to our knowledge of the cell lines and of the Drosophila transcriptome in several ways. We summarize the expression of previously annotated genes in each of the 25 lines with emphasis on what those patterns reveal about the origins of the lines and the stability of spatial expression patterns. In addition, we offer an initial analysis of previously unannotated transcripts in the cell lines.« less
Generation of SV40-transformed rabbit tracheal-epithelial-cell-derived blastocyst by somatic cell nuclear transfer

PubMed Central

de Semir, D.; Maurisse, R.; Du, F.; Xu, J.; Yang, X.; Illek, B.; Gruenert, D. C.

2013-01-01

The prospect of developing large animal models for the study of inherited diseases, such as cystic fibrosis (CF), through somatic cell nuclear transfer (SCNT) has opened up new opportunities for enhancing our understanding of disease pathology and for identifying new therapies. Thus, the development of species-specific in vitro cell systems that will provide broader insight into organ- and cell-type-specific functions relevant to the pathology of the disease is crucial. Studies have been undertaken to establish transformed rabbit airway epithelial cell lines that display differentiated features characteristic of the primary airway epithelium. This study describes the successful establishment and characterization of two SV40-transformed rabbit tracheal epithelial cell lines. These cell lines, 5RTEo- and 9RTEo-, express the CF transmembrane conductance regulator (CFTR) gene, retain epithelial-specific differentiated morphology and show CFTR-based cAMP-dependent Cl− ion transport across the apical membrane of a confluent monolayer. Immunocytochemical analysis indicates the presence of airway cytokeratins and tight-junction proteins in the 9RTEo- cell line after multiple generations. However, the tight junctions appear to diminish in their efficacy in both cell lines after at least 100 generations. Initial SCNT studies with the 9RTEo- cells have revealed that SV40-transformed rabbit airway epithelial donor cells can be used to generate blastocysts. These cell systems provide valuable models for studying the developmental and metabolic modulation of CFTR gene expression and rabbit airway epithelial cell biology. PMID:22234514

Maintenance of Epithelial Stem Cells by Cbl Proteins

DTIC Science & Technology

2012-09-01

may be a potential mechanism behind inhibition of MEC differentiation in the absence of Cbl. 7 Figure 1. Flow cytometry analysis of hTERT...results in tumors at the implant site as well as distant metastases To assess whether ErbB2-dependent MPPS1 cells retain their oncogenic potential ...the levels of ErbB2 are not lost in this cell line during culture [ ]. This in itself suggested the potential dependence of oncogenic traits of MPPS1
Development and characterization of a cell line from Pacific herring, Clupea harengus pallasi, sensitive to both naphthalene cytotoxicity and infection by viral hemorrhagic septicemia virus.

PubMed

Ganassin, R C; Sanders, S M; Kennedy, C J; Joyce, E M; Bols, N C

1999-01-01

A cell line, PHL, has been successfully established from newly hatched herring larvae. The cells are maintained in growth medium consisting of Leibovitz's L-15 supplemented with 15% fetal bovine serum (FBS), and have been cryopreserved and maintain viability after thawing. These cells retain a diploid karotype after 65 population doublings. PHL are susceptible to infection by the North American strain of viral hemorrhagic septicemia (VHS) virus, and are sensitive to the cytotoxic effects of naphthalene, a common environmental contaminant. Naphthalene is a component of crude and refined oil, and may be found in the marine environment following acute events such as oil spills. In addition, chronic sources of naphthalene contamination include offshore drilling and petroleum contamination from areas such as docks and marinas that have creosote-treated docks and pilings and also receive constant small inputs of petroleum products. This cell line should be useful for investigations of the toxicity of naphthalene and other petroleum components to juvenile herring. In addition, studies of the VHS virus will be facilitated by the availability of a susceptible cell line from an alternative species.
A novel rat fibrosarcoma cell line from transformed bone marrow-derived mesenchymal stem cells with maintained in vitro and in vivo stemness properties.

PubMed

Wang, Meng-Yu; Nestvold, Janne; Rekdal, Øystein; Kvalheim, Gunnar; Fodstad, Øystein

2017-03-15

Increasing evidence suggests a possible relationship between mesenchymal stem cells (MSCs) and sarcoma. MSCs are hypothesized to be the cells initiating sarcomagenesis, and cancer stem cells (CSCs) sharing features of MSCs have been identified in sarcomas. Here, we report on the characteristics of a bone marrow-derived rat mesenchymal stem cell line that spontaneously transformed in long-term culture. The rat transformed mesenchymal stem cells (rTMSCs) produced soft-tissue fibrosarcomas in immunocompromised mice and immunocompetent rats. In vitro, the rTMSCs displayed increased proliferation capacity compared to the untransformed cell line. The transformed MSCs maintained the mesenchymal phenotype by expression of the stem cell marker CD 90 and the lack of hematopoietic and endothelial markers. Cytogenetic analysis detected trisomy 6 in the rTMSCs. Side population (SP) isolation and tumorsphere cultivation of the transformed cells confirmed the presence of CSCs among the rTMSCs. Importantly, the rTMSCs retained their differentiation capacity towards osteogenic and adipogenic lineages. This transformed MSC-based cell line may be valuable in examining the balance in a mixed cell population between cancer stem cell properties and the ability to differentiate to specific non-transformed cell populations. Moreover, it may also be a useful tool to evaluate the efficacy of novel targeted immunotherapies in vivo. Copyright © 2017 Elsevier Inc. All rights reserved.
Ex vivo culture of tumor cells from N-methyl-N-nitrosourea-induced bladder cancer in rats: Development of organoids and an immortalized cell line.

PubMed

Yoshida, Takahiro; Kates, Max; Sopko, Nikolai A; Liu, Xiaopu; Singh, Alok K; Bishai, William R; Joice, Gregory; McConkey, David J; Bivalacqua, Trinity J

2018-04-01

We ex vivo cultured primary tumor cells from N-methyl-N-nitrosourea (MNU)-induced bladder tumors in rats and established an immortalized cell line from them. Bladder tumors in rats were induced by instillation of MNU into the murine bladder. Primary tumor cells were prepared by the cancer-tissue originated spheroid method. An immortalized cell line was established by co-culture with fibroblasts. The cultured tumor cells were molecularly and functionally characterized by quantitative real-time polymerase chain reaction, Western blot, growth assay, and transwell migration assay. Primary tumor cells were successfully prepared as multicellular spheroids from MNU-induced bladder tumors. The differentiation marker expression patterns observed in the original tumors were largely retained in the spheroids. We succeeded in establishing a cell line from the spheroids and named it T-MNU-1. Although basal markers (CK14 and CK5) were enriched in T-MNU-1 compared to the spheroids, T-MNU-1 expressed both luminal and basal markers. T-MNU-1 was able to migrate through a transwell. Tumor cells in MNU-induced bladder tumors were successfully cultured ex vivo as organoids, and an immortalized cell line was also established from them. The ex vivo models offer a platform that enables analysis of intrinsic characteristics of tumor cells excluding influence of microenvironment in MNU-induced bladder tumors. Copyright © 2017 Elsevier Inc. All rights reserved.
Development of 3D imaging technique of reconstructed human epidermis with immortalized human epidermal cell line.

PubMed

Inoue, Yu; Hasegawa, Seiji; Miyachi, Katsuma; Yamada, Takaaki; Nakata, Satoru; Ipponjima, Sari; Hibi, Terumasa; Nemoto, Tomomi; Tanaka, Masahiko; Suzuki, Ryo; Hirashima, Naohide

2018-05-01

The epidermis, the outermost layer of the skin, retains moisture and functions as a physical barrier against the external environment. Epidermal cells are continuously replaced by turnover, and thus to understand in detail the dynamic cellular events in the epidermis, techniques to observe live tissues in 3D are required. Here, we established a live 3D imaging technique for epidermis models. We first obtained immortalized human epidermal cell lines which have a normal differentiation capacity and fluorescence-labelled cytoplasm or nuclei. The reconstituted 3D epidermis was prepared with these lines. Using this culture system, we were able to observe the structure of the reconstituted epidermis live in 3D, which was similar to an in vivo epidermis, and evaluate the effect of a skin irritant. This technique may be useful for dermatological science and drug development. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Label retention identifies a multipotent mesenchymal stem cell-like population in the postnatal thymus.

PubMed

Osada, Masako; Singh, Varan J; Wu, Kenmin; Sant'Angelo, Derek B; Pezzano, Mark

2013-01-01

Thymic microenvironments are essential for the proper development and selection of T cells critical for a functional and self-tolerant adaptive immune response. While significant turnover occurs, it is unclear whether populations of adult stem cells contribute to the maintenance of postnatal thymic epithelial microenvironments. Here, the slow cycling characteristic of stem cells and their property of label-retention were used to identify a K5-expressing thymic stromal cell population capable of generating clonal cell lines that retain the capacity to differentiate into a number of mesenchymal lineages including adipocytes, chondrocytes and osteoblasts suggesting a mesenchymal stem cell-like phenotype. Using cell surface analysis both culture expanded LRCs and clonal thymic mesenchymal cell lines were found to express Sca1, PDGFRα, PDGFRβ,CD29, CD44, CD49F, and CD90 similar to MSCs. Sorted GFP-expressing stroma, that give rise to TMSC lines, contribute to thymic architecture when reaggregated with fetal stroma and transplanted under the kidney capsule of nude mice. Together these results show that the postnatal thymus contains a population of mesenchymal stem cells that can be maintained in culture and suggests they may contribute to the maintenance of functional thymic microenvironments.
Air-dried cells from the anhydrobiotic insect, Polypedilum vanderplanki, can survive long term preservation at room temperature and retain proliferation potential after rehydration.

PubMed

Watanabe, Kazuyo; Imanishi, Shigeo; Akiduki, Gaku; Cornette, Richard; Okuda, Takashi

2016-08-01

Pv11, a cell line derived from the anhydrobiotic insect, Polypedilum vanderplanki, was preserved in a dry form (only 6% residual moisture) at room temperature for up to 251 days and restarted proliferating after rehydration. A previous study already reported survival of Pv11 cells after desiccation, but without subsequent proliferation. Here, the protocol was improved to increase survival and achieve proliferation of Pv11 cells after dry storage. The method basically included preincubation, desiccation and rehydration processes and each step was investigated. So far, preincubation in a 600 mM trehalose solution for 48 h before dehydration was the most favourable preconditioning to achieve successful dry preservation of Pv11 cells, allowing about 16% of survival after rehydration and subsequent cell proliferation. Although the simple air-dry method established for Pv11 cells here was not applicable for successful dry-preservation of other insect cell lines, Pv11 is the first dry-preservable animal cell line and will surely contribute not only to basic but also applied sciences. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Cell culture of the mucinous variant of human colorectal carcinoma.

PubMed

Tibbetts, L M; Chu, M Y; Vezeridis, M P; Miller, P G; Tibbetts, L L; Poisson, M H; Camara, P D; Calabresi, P

1988-07-01

Two cell lines, RW-2982 and RW-7213, have been established for the first time from the mucinous variant of human colorectal carcinoma, which is a distinctive and important subtype that has a worse prognosis than the more common nonmucogenic large bowel carcinoma. Methods of establishment and observations made during 7 and 3 years, respectively, of continuous culture are described. These cell lines required 4-9 months of adaptation to tissue culture conditions before noticeable growth occurred. Both cell lines have the following unique properties: (a) growth in vitro as delicate branching three-dimensional tumor particles within a wide gel of insoluble, often translucent mucus (proteoglycan); (b) production of large quantities of carcinoembryonic antigen; (c) ability to survive or adapt to growth in media free of serum, hormones, growth factors, and all protein; and (d) tumorigenicity in multiple sites in nude mice, including liver, with especially rapid growth in the peritoneal cavity as gelatinous material that is nonadherent and noninvasive and thus resembles pseudomyxoma peritonei. Unlike other reported colorectal cell lines, these mucus-coated particulate cell lines will not readily grow as monolayers and grow much more slowly with a doubling time of 2 weeks or more. A serially transplantable tumor from the RW-7213 surgical specimen has also been maintained in nude mice since August 8, 1984. This tumor retains properties of the original specimen. Observations made on the tumor biology of mucogenic colorectal carcinoma using these cell lines are discussed.
Promotion of haematopoietic activity in embryonic stem cells by the aorta-gonad-mesonephros microenvironment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krassowska, Anna; Gordon-Keylock, Sabrina; Samuel, Kay

We investigated whether the in vitro differentiation of ES cells into haematopoietic progenitors could be enhanced by exposure to the aorta-gonadal-mesonephros (AGM) microenvironment that is involved in the generation of haematopoietic stem cells (HSC) during embryonic development. We established a co-culture system that combines the requirements for primary organ culture and differentiating ES cells and showed that exposure of differentiating ES cells to the primary AGM region results in a significant increase in the number of ES-derived haematopoietic progenitors. Co-culture of ES cells on the AM20-1B4 stromal cell line derived from the AGM region also increases haematopoietic activity. We concludemore » that factors promoting the haematopoietic activity of differentiating ES cells present in primary AGM explants are partially retained in the AM20.1B4 stromal cell line and that these factors are likely to be different to those required for adult HSC maintenance.« less
Properties of murine embryonic stem cells maintained on human foreskin fibroblasts without LIF.

PubMed

Meng, G L; Zur Nieden, N I; Liu, S Y; Cormier, J T; Kallos, M S; Rancourt, D E

2008-04-01

In embryonic stem (ES) cells, leukemia inhibitory factor (LIF)/STAT3, wnt and nodal/activin signaling are mainly active to control pluripotency during expansion. To maintain pluripotency, ES cells are typically cultured on feeder cells of varying origins. Murine ES cells are commonly cultured on murine embryonic fibroblasts (MEFs), which senesce early and must be frequently prepared. This process is laborious and leads to batch variation presenting a challenge for high-throughput ES cell expansion. Although some cell lines can be sustained by exogenous LIF, this method is costly. We present here a novel and inexpensive culture method for expanding murine ES cells on human foreskin fibroblast (HFF) feeders. After 20 passages on HFFs without LIF, ES cell lines showed normal expression levels of pluripotency markers, maintained a normal karyotype and retained the ability to contribute to the germline. As HFFs do not senesce for at least 62 passages, they present a vast supply of feeders. Copyright 2007 Wiley-Liss, Inc.
Generation of induced pluripotent stem cells derived from an autosomal dominant polycystic kidney disease patient with a p.Ser1457fs mutation in PKD1.

PubMed

Huang, Ching-Ying; Ho, Ming-Ching; Lee, Jia-Jung; Hwang, Daw-Yang; Ko, Hui-Wen; Cheng, Yu-Che; Hsu, Yu-Hung; Lu, Huai-En; Chen, Hung-Chun; Hsieh, Patrick C H

2017-10-01

Autosomal dominant polycystic kidney disease is one of the most prevalent forms of inherited cystic kidney disease, and can be characterized by kidney cyst formation and enlargement. Here we report the generation of a Type 1 ADPKD disease iPS cell line, IBMS-iPSC-012-12, which retains the conserved deletion of PKD1, normal karyotype and exhibits the properties of pluripotent stem cells such as ES-like morphology, expression of pluripotent markers and capacity to differentiate into all three germ layers. Our results show that we have successfully generated a patient-specific iPS cell line with a mutation in PKD1 for study of renal disease pathophysiology. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Li-An; Department of Pediatric Dentistry, School of Stomatology, The Fourth Military Medical University, Xi-an; Yuan, Guohua

Generation of a floxed Bmp2/4 osteoblast cell line is a valuable tool for studying the modulatory effects of Bmp2 and Bmp4 on osteoblast differentiation as well as relevant molecular events. In this study, primary floxed Bmp2/4 mouse osteoblasts were cultured and transfected with simian virus 40 large T-antigen. Transfection was verified by polymerase chain reaction (PCR) and immunohistochemistry. To examine the characteristics of the transfected cells, morphology, proliferation and mineralization were analyzed, expression of cell-specific genes including Runx2, ATF4, Dlx3, Osx, dentin matrix protein 1, bone sialoprotein, osteopontin, osteocalcin, osteonectin and collagen type I was detected. These results show thatmore » transfected floxed Bmp2/4 osteoblasts bypassed senescence with a higher proliferation rate, but retain the genotypic and phenotypic characteristics similar to the primary cells. Thus, we for the first time demonstrate the establishment of an immortalized mouse floxed Bmp2/4 osteoblast cell line.« less
Polymer microfilters with nanostructured surfaces for the culture of circulating cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makarova, Olga V.; Adams, Daniel L.; Divan, Ralu

There is a critical need to improve the accuracy of drug screening and testing through the development of in vitro culture systems that more effectively mimic the in vivo environment. Surface topographical features on the nanoscale level, in short nanotopography, effect the cell growth patterns, and hence affect cell function in culture. We report the preliminary results on the fabrication, and subsequent cellular growth, of nanoscale surface topography on polymer microfilters using cell lines as a precursor to circulating tumor cells (CTCs). To create various nanoscale features on the microfilter surface, we used reactive ion etching (RIE) with and withoutmore » an etching mask. An anodized aluminum oxide (AAO) membrane fabricated directly on the polymer surface served as an etching mask. Polymer filters with a variety of modified surfaces were used to compare the effects on the culture of cancer cell lines in blank culture wells, with untreated microfilters or with RIE-treated microfilters. We then report the differences of cell shape, phenotype and growth patterns of bladder and glioblastoma cancer cell lines after isolation on the various types of material modifications. Our data suggest that RIE modified polymer filters can isolate model cell lines while retaining ell viability, and that the RIE filter modification allows T24 monolayering cells to proliferate as a structured cluster. Copyright 2016 The Authors. Published by Elsevier B.V. All rights reserved.« less
Rho kinase inhibitor Y-27632 and Accutase dramatically increase mouse embryonic stem cell derivation.

PubMed

Zhang, Peng; Wu, Xinglong; Hu, Chunchao; Wang, Pengbo; Li, Xiangyun

2012-01-01

Although it has been 30 yr since the development of derivation methods for mouse embryonic stem (ES) cells, the biology of derivation of ES cells is poorly understood and the efficiency varies dramatically between cell lines. Recently, the Rho kinase inhibitor Y-27632 and the cell dissociation reagent Accutase were reported to significantly inhibit apoptosis of human ES cells during passaging. Therefore, in the current study, C57BL/6×129/Sv mouse blastocysts were used to evaluate the effect of the combination of the two reagents instead of using the conventional 129 line in mouse ES cell derivation. The data presented in this study suggests that the combination of Y-27632 and Accutase significantly increases the efficiency of mouse ES cell derivation; furthermore, no negative side effects were observed with Y-27632 and Accutase treatment. The newly established ES cell lines retain stable karyotype, surface markers expression, formed teratomas, and contributed to viable chimeras and germline transmission by tetraploid complementation assay. In addition, Y-27632 improved embryoid body formation of ES cells. During ES cell microinjection, Y-27632 prevented the formation of dissociation-induced cell blebs and facilitates the selection and the capture of intact cells. The methods presented in this study clearly demonstrate that inhibition of Rho kinase with Y-27632 and Accutase dissociation improve the derivation efficiently and reproducibility of mouse ES cell generation which is essential for reducing variability in the results obtained from different cell lines.
Genetic separation of phototropism from blue light inhibition of hypocotyl elongation on Arabidopsis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liscum, E.; Young, J.C.; Hangarter, R.P.

1991-05-01

Phototropism and inhibition of stem elongation occur in response to blue light-induced inhibition of cell elongation. However, phototropism is a low fluence response and inhibition of hypocotyl elongation is a high irradiance response. The authors have isolated several mutant lines of Arabidopsis which lack blue light-induced inhibition of hypocotyl elongation but retain normal phototropic functions. In addition, a mutant line which completely lacks the phototropic response retains normal blue light-induced inhibition of hypocotyl elongation. F1 progeny of crosses between these two mutant classes exhibited wild-type phototropism and inhibition of hypocotyl elongation in response to blue light stimuli. In the F2more » generation, one in sixteen seedlings were double mutants lacking both phototropism and blue light-induced hypocotyl growth inhibition. These studies conclusively show that blue light-induced phototropism and hypocotyl growth inhibition function through genetically distinct signal transduction or response systems.« less
Mitochondrial Transfer by Photothermal Nanoblade Restores Metabolite Profile in Mammalian Cells.

PubMed

Wu, Ting-Hsiang; Sagullo, Enrico; Case, Dana; Zheng, Xin; Li, Yanjing; Hong, Jason S; TeSlaa, Tara; Patananan, Alexander N; McCaffery, J Michael; Niazi, Kayvan; Braas, Daniel; Koehler, Carla M; Graeber, Thomas G; Chiou, Pei-Yu; Teitell, Michael A

2016-05-10

mtDNA sequence alterations are challenging to generate but desirable for basic studies and potential correction of mtDNA diseases. Here, we report a new method for transferring isolated mitochondria into somatic mammalian cells using a photothermal nanoblade, which bypasses endocytosis and cell fusion. The nanoblade rescued the pyrimidine auxotroph phenotype and respiration of ρ0 cells that lack mtDNA. Three stable isogenic nanoblade-rescued clones grown in uridine-free medium showed distinct bioenergetics profiles. Rescue lines 1 and 3 reestablished nucleus-encoded anapleurotic and catapleurotic enzyme gene expression patterns and had metabolite profiles similar to the parent cells from which the ρ0 recipient cells were derived. By contrast, rescue line 2 retained a ρ0 cell metabolic phenotype despite growth in uridine-free selection. The known influence of metabolite levels on cellular processes, including epigenome modifications and gene expression, suggests metabolite profiling can help assess the quality and function of mtDNA-modified cells. Copyright © 2016 Elsevier Inc. All rights reserved.
[Continuously perfused cultivation of genetically-engineered CHO cells producing prothrombin in a modified Super-Spinner].

PubMed

Chen, Z L; Iding, K; Lütkemeyer, D; Lehmann, J

2001-01-01

A Super-Spinner was Modified by mounting a stainless steel filter(pore size 75 microns) to the impeller shaft to retain cells while fresh nutrient is perfused. Using Macroporous microcarrier Cytopore 1, continuously perfused cultivation of a recombinant CHO cell line, CHO2DS producing prothrombin was performed with the perfusion of a protein-free medium DF6S. The cell retention rate was more than 90% during the 24 days continuously perfused cultivation. The viable cell density of CHO2DS and prothrombin concentration reached 4.62 x 10(6)(cells.m/L) and 11.3(mg/L) respectively after 9 days culture.
A homozygous Keap1-knockout human embryonic stem cell line generated using CRISPR/Cas9 mediates gene targeting.

PubMed

Kim, So-Jung; Habib, Omer; Kim, Jin-Soo; Han, Hyo-Won; Koo, Soo Kyung; Kim, Jung-Hyun

2017-03-01

Kelch-like ECH-associated protein 1 (keap1) is a cysteine-rich protein that interacts with transcription factor Nrf2 in a redox-sensitive manner, leading to the degradation of Nrf2 (Kim et al., 2014a). Disruption of Keap1 results in the induction of Nrf2-related signaling pathways involving the expression of a set of anti-oxidant and anti-inflammatory genes. We generated biallelic mutants of the Keap1 gene using a CRISPR-Cas9 genome editing method in the H9 human embryonic stem cell (hESC). The Keap1 homozygous-knockout H9 cell line retained normal morphology, gene expression, and in vivo differentiation potential. Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.
In vitro antileukaemic activity of extracts from chokeberry (Aronia melanocarpa [Michx] Elliott) and mulberry (Morus alba L.) leaves against sensitive and multidrug resistant HL60 cells.

PubMed

Skupień, Katarzyna; Kostrzewa-Nowak, Dorota; Oszmiański, Jan; Tarasiuk, Jolanta

2008-05-01

The aim of the present study was to determine in vitro antileukaemic activities of extracts obtained from chokeberry (Aronia melanocarpa [Michx] Elliot) and mulberry (Morus alba L.) leaves against promyelocytic HL60 cell line and its multidrug resistant sublines exhibiting two different MDR phenotypes: HL60/VINC (overexpressing P-glycoprotein) and HL60/DOX (overexpressing MRP1 protein). It was found that the extracts from chokeberry and mulberry leaves were active against the sensitive leukaemic cell line HL60 and retained the in vitro activity against multidrug resistant sublines (HL60/VINC and HL60/DOX). The values of resistance factor (RF) found for these extracts were very low lying in the range 1.2-1.6.
Establishment and characterization of a new cell line (SSP-9) derived from Atlantic salmon Salmo salar that expresses type I ifn.

PubMed

Rodriguez Saint-Jean, S; González, C; Monrás, M; Romero, A; Ballesteros, N; Enríquez, R; Perez-Prieto, S

2014-11-01

In the present work, the establishment and biological characterization of a new cell line, SSP-9, derived from the pronephros of the Atlantic salmon Salmo salar, are reported. These cells grew well in Leibovitz's (L15) medium supplemented with 10% foetal calf serum at temperatures from 15 to 25° C, and they have been sub-cultured over 100 passages to produce a continuous cell line with an epithelial-like morphology. The SSP-9 cells attached and spread efficiently at different plating densities, retaining 80% of cell viability after storage in liquid nitrogen. When karyotyped, the cells had 40-52 chromosomes, with a modal number of 48. Viral susceptibility tests showed that SSP-9 cells were susceptible to infectious pancreatic necrosis virus and infectious haematopoietic necrosis virus, producing infectious virus and regular cytopathic effects. Moreover, these cells could be stimulated by poly I:C, showing significant up-regulation in the expression of the genes that regulate immune responses, such as ifn and mx-1. SSP-9 cells constitutively express genes characteristic of macrophages, such as major histocompatibility complex (mhc-II) and interleukin 12b (il-12b), and flow cytometry assays confirmed that SSP-9 cells can be permanently transfected with plasmids expressing a reporter gene. Accordingly, this new cell line is apparently suitable for transgenic manipulation, and to study host cell-virus interactions and immune processes. © 2014 The Fisheries Society of the British Isles.

EGFR gene overexpression retained in an invasive xenograft model by solid orthotopic transplantation of human glioblastoma multiforme into nude mice.

PubMed

Yi, Diao; Hua, Tian Xin; Lin, Huang Yan

2011-03-01

Orthotopic xenograft animal model from human glioblastoma multiforme (GBM) cell lines often do not recapitulate an extremely important aspect of invasive growth and epidermal growth factor receptor (EGFR) gene overexpression of human GBM. We developed an orthotopic xenograft model by solid transplantation of human GBM into the brain of nude mouse. The orthotopic xenografts sharing the same histopathological features with their original human GBMs were highly invasive and retained the overexpression of EGFR gene. The murine orthotopic GBM models constitute a valuable in vivo system for preclinical studies to test novel therapies for human GBM.
Isolation, characterization and recombinant protein expression in Veggie-CHO: A serum-free CHO host cell line.

PubMed

Rasmussen, B; Davis, R; Thomas, J; Reddy, P

1998-11-01

The dihydrofolate reductase-deficient Chinese hamster ovary cell line, DXB11-CHO, commonly used as a host cell for the production of recombinant proteins requires 7.5% serum-supplementation for optimal growth. Regulatory issues surrounding the use of serum in clinical production processes and the direct and indirect costs of using serum in large-scale production and recovery processes have triggered efforts to derive serum-independent host cell lines. We have successfully isolated a serum-free host that we named Veggie- CHO. Veggie-CHO was generated by adapting DXB11-CHO cells to growth in serum-free media in the absence of exogenous growth factors such as Transferrin and Insulin-like growth factor, which we have previously shown to be essential for growth and viability of DXB11- CHO cells. Veggie-CHO cells have been shown to maintain an average doubling time of 22 hr in continuous growth cultures over a period of three months and have retained the dihydrofolate reductase -deficient phenotype of their parental DXB11-CHO cells. These properties and the stability of its serum-free phenotype have allowed the use of Veggie- CHO as host cells for transfection and amplified expression of recombinant proteins. We describe the derivation a serum-free recombinant cell line with an average doubling time of 20 hr and specific productivity of 2.5 Units recombinant Flt-3L protein per 10e6 cells per day.
Selective loss of nucleoside carrier expression in rat hepatocarcinomas.

PubMed

Dragan, Y; Valdés, R; Gomez-Angelats, M; Felipe, A; Javier Casado, F; Pitot, H; Pastor-Anglada, M

2000-08-01

Evidence that hepatoma cell lines show differential expression of concentrative nucleoside transporters (CNT1 and CNT2) prompted us to study the transporter proteins in 2 models of hepatocarcinogenesis, the chemically induced Solt and Farber model and the albumin-SV40 large T antigen (Alb-SV40) transgenic rat. CNT1 expression was lower in tumor biopsy specimens from Alb-SV40 rat livers than in normal tissue. Immunocytochemistry revealed that the CNT1 protein was indeed absent in the tumor lesions. CNT1 was also absent in a cell line, L25, derived from the Alb-SV40 transgenic rat liver tumors, whereas another cell line, L37, derived from the normal-appearing parenchyma, retained the expression of both carrier isoforms. The protein expression correlated with the nucleoside transport properties of these cell lines. Moreover, although CNT2 expression was highly dependent on the growth characteristics of the 2 cell lines, as was CNT1 (albeit to a lower extent) in L37 cells, it was not expressed in L25 cells at any stage of cell growth. In contrast to the transgenic model of hepatocarcinogenesis, in the chemically induced tumors the expression of CNT2 was lower, although still detectable. In summary, these data indicate that hepatocarcinogenesis leads to a selective loss or diminished expression of nucleoside carrier isoforms, a feature that may be relevant to our understanding of the molecular basis of the bioavailability of those drugs that are nucleoside derivatives and may be substrates of these carriers. The transport properties and isoform-expression profile of the L25 and L37 cell lines make them suitable hepatocyte culture models with which to study nucleoside transport processes and drug sensitivity.
A novel dual-functioning ruthenium(II)-arene complex of an anti-microbial ciprofloxacin derivative - Anti-proliferative and anti-microbial activity.

PubMed

Ude, Ziga; Romero-Canelón, Isolda; Twamley, Brendan; Fitzgerald Hughes, Deirdre; Sadler, Peter J; Marmion, Celine J

2016-07-01

7-(4-(Decanoyl)piperazin-1-yl)-ciprofloxacin, CipA, (1) which is an analogue of the antibiotic ciprofloxacin, and its ruthenium(II) complex [Ru(η(6)-p-cymene)(CipA-H)Cl], (2) have been synthesised and the x-ray crystal structures of 1·1.3H2O·0.6CH3OH and 2·CH3OH·0.5H2O determined. The complex adopts a typical pseudo-octahedral 'piano-stool' geometry, with Ru(II) π-bonded to the p-cymene ring and σ-bonded to a chloride and two oxygen atoms of the chelated fluoroquinolone ligand. The complex is highly cytotoxic in the low μM range and is as potent as the clinical drug cisplatin against the human cancer cell lines A2780, A549, HCT116, and PC3. It is also highly cytotoxic against cisplatin- and oxaliplatin-resistant cell lines suggesting a different mechanism of action. The complex also retained low μM cytotoxicity against the human colon cancer cell line HCT116p53 in which the tumour suppressor p53 had been knocked out, suggesting that the potent anti-proliferative properties associated with this complex are independent of the status of p53 (in contrast to cisplatin). The complex also retained moderate anti-bacterial activity in two Escherichia coli, a laboratory strain and a clinical isolate resistant to first, second and third generation β-lactam antibiotics. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
A targeted neuroglial reporter line generated by homologous recombination in human embryonic stem cells.

PubMed

Xue, Haipeng; Wu, Sen; Papadeas, Sophia T; Spusta, Steve; Swistowska, Anna Maria; MacArthur, Chad C; Mattson, Mark P; Maragakis, Nicholas J; Capecchi, Mario R; Rao, Mahendra S; Zeng, Xianmin; Liu, Ying

2009-08-01

In this study, we targeted Olig2, a basic helix-loop-helix transcription factor that plays an important role in motoneuron and oligodendrocyte development, in human embryonic stem cell (hESC) line BG01 by homologous recombination. One allele of Olig2 locus was replaced by a green fluorescent protein (GFP) cassette with a targeting efficiency of 5.7%. Targeted clone R-Olig2 (like the other clones) retained pluripotency, typical hESC morphology, and a normal parental karyotype 46,XY. Most importantly, GFP expression recapitulated endogenous Olig2 expression when R-Olig2 was induced by sonic hedgehog and retinoic acid, and GFP-positive cells could be purified by fluorescence-activated cell sorting. Consistent with previous reports on rodents, early GFP-expressing cells appeared biased to a neuronal fate, whereas late GFP-expressing cells appeared biased to an oligodendrocytic fate. This was corroborated by myoblast coculture, transplantation into the rat spinal cords, and whole genome expression profiling. The present work reports an hESC reporter line generated by homologous recombination targeting a neural lineage-specific gene, which can be differentiated and sorted to obtain pure neural progenitor populations.
In vivo biomarker expression patterns are preserved in 3D cultures of Prostate Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Windus, Louisa C.E.; Kiss, Debra L.; Glover, Tristan

2012-11-15

Here we report that Prostate Cancer (PCa) cell-lines DU145, PC3, LNCaP and RWPE-1 grown in 3D matrices in contrast to conventional 2D monolayers, display distinct differences in cell morphology, proliferation and expression of important biomarker proteins associated with cancer progression. Consistent with in vivo growth rates, in 3D cultures, all PCa cell-lines were found to proliferate at significantly lower rates in comparison to their 2D counterparts. Moreover, when grown in a 3D matrix, metastatic PC3 cell-lines were found to mimic more precisely protein expression patterns of metastatic tumour formation as found in vivo. In comparison to the prostate epithelial cell-linemore » RWPE-1, metastatic PC3 cell-lines exhibited a down-regulation of E-cadherin and {alpha}6 integrin expression and an up-regulation of N-cadherin, Vimentin and {beta}1 integrin expression and re-expressed non-transcriptionally active AR. In comparison to the non-invasive LNCaP cell-lines, PC3 cells were found to have an up-regulation of chemokine receptor CXCR4, consistent with a metastatic phenotype. In 2D cultures, there was little distinction in protein expression between metastatic, non-invasive and epithelial cells. These results suggest that 3D cultures are more representative of in vivo morphology and may serve as a more biologically relevant model in the drug discovery pipeline. -- Highlights: Black-Right-Pointing-Pointer We developed and optimised 3D culturing techniques for Prostate Cancer cell-lines. Black-Right-Pointing-Pointer We investigated biomarker expression in 2D versus 3D culture techniques. Black-Right-Pointing-Pointer Metastatic PC3 cells re-expressed non-transcriptionally active androgen receptor. Black-Right-Pointing-Pointer Metastatic PCa cell lines retain in vivo-like antigenic profiles in 3D cultures.« less
Development and Characterisation of a Human Chronic Skin Wound Cell Line—Towards an Alternative for Animal Experimentation

PubMed Central

Wall, Ivan B.; Peake, Matthew; Kipling, David; Giles, Peter; Thomas, David W.

2018-01-01

Background: Chronic skin wounds are a growing financial burden for healthcare providers, causing discomfort/immobility to patients. Whilst animal chronic wound models have been developed to allow for mechanistic studies and to develop/test potential therapies, such systems are not good representations of the human chronic wound state. As an alternative, human chronic wound fibroblasts (CWFs) have permitted an insight into the dysfunctional cellular mechanisms that are associated with these wounds. However, such cells strains have a limited replicative lifespan and therefore a limited reproducibility/usefulness. Objectives: To develop/characterise immortalised cell lines of CWF and patient-matched normal fibroblasts (NFs). Methods and Results: Immortalisation with human telomerase resulted in both CWF and NF proliferating well beyond their replicative senescence end-point (respective cell strains senesced as normal). Gene expression analysis demonstrated that, whilst proliferation-associated genes were up-regulated in the cell lines (as would be expected), the immortalisation process did not significantly affect the disease-specific genotype. Immortalised CWF (as compared to NF) also retained a distinct impairment in their wound repopulation potential (in line with CWF cell strains). Conclusions: These novel CWF cell lines are a credible animal alternative and could be a valuable research tool for understanding both the aetiology of chronic skin wounds and for therapeutic pre-screening. PMID:29584680
Electrical transmission line diametrical retainer

DOEpatents

Hall, David R.; Hall, Jr., H. Tracy; Pixton, David; Dahlgren, Scott; Sneddon, Cameron; Briscoe, Michael; Fox, Joe

2004-12-14

The invention is a mechanism for retaining an electrical transmission line. In one embodiment of the invention it is a system for retaining an electrical transmission line within down hole components. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string. The system also includes a coaxial cable running between the first and second end of a drill pipe, the coaxial cable having a conductive tube and a conductive core within it. The invention allows the electrical transmission line to with stand the tension and compression of drill pipe during routine drilling cycles.
In vitro effects of dental cements on hard and soft tissues associated with dental implants.

PubMed

Rodriguez, Lucas C; Saba, Juliana N; Chung, Kwok-Hung; Wadhwani, Chandur; Rodrigues, Danieli C

2017-07-01

Dental cements for cement-retained restorations are often chosen based on clinician preference for the product's material properties, mixing process, delivery mechanism, or viscosity. The composition of dental cement may play a significant role in the proliferation or inhibition of different bacterial strains associated with peri-implant disease, and the effect of dental cements on host cellular proliferation may provide further insight into appropriate cement material selection. The purpose of this in vitro study was to investigate the cellular host response of bone cells (osteoblasts) and soft tissue cells (gingival fibroblasts) to dental cements. Zinc oxide (eugenol and noneugenol), zinc phosphate, and acrylic resin cements were molded into pellets and directly applied to confluent preosteoblast (cell line MC3T3 E1) or gingival fibroblast cell cultures (cell line HGF) to determine cellular viability after exposure. Controls were defined as confluent cell cultures with no cement exposure. Direct contact cell culture testing was conducted following International Organization for Standardization 10993 methods, and all experiments were performed in triplicate. To compare either the MC3T3 E1 cell line, or the HGF cell line alone, a 1-way ANOVA test with multiple comparisons was used (α=.05). To compare the MC3T3 E1 cell line results and the HGF cell line results, a 2-way ANOVA test with multiple comparisons was used (α=.05). The results of this study illustrated that while both bone and soft tissue cell lines were vulnerable to the dental cement test materials, the soft tissue cell line (human gingival fibroblasts) was more susceptible to reduced cellular viability after exposure. The HGF cell line was much more sensitive to cement exposure. Here, the acrylic resin, zinc oxide (eugenol), and zinc phosphate cements significantly reduced cellular viability after exposure with respect to HGF cells only. Within the limitation of this in vitro cellular study, the results indicated that cell response to various implant cements varied significantly, with osteoblast proliferation much less affected than gingival fibroblast cells. Furthermore, the zinc oxide noneugenol dental cement appeared to affect the cell lines significantly less than the other test cements. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.
Derivation and characterisation of the human embryonic stem cell lines, NOTT1 and NOTT2.

PubMed

Priddle, Helen; Allegrucci, Cinzia; Burridge, Paul; Munoz, Maria; Smith, Nigel M; Devlin, Lyndsey; Sjoblom, Cecilia; Chamberlain, Sarah; Watson, Sue; Young, Lorraine E; Denning, Chris

2010-04-01

The ability to maintain human embryonic stem cells (hESCs) during long-term culture and yet induce differentiation to multiple lineages potentially provides a novel approach to address various biomedical problems. Here, we describe derivation of hESC lines, NOTT1 and NOTT2, from human blastocysts graded as 3BC and 3CB, respectively. Both lines were successfully maintained as colonies by mechanical passaging on mouse embryonic feeder cells or as monolayers by trypsin-passaging in feeder-free conditions on Matrigel. Undifferentiated cells retained expression of pluripotency markers (OCT4, NANOG, SSEA-4, TRA-1-60 and TRA-1-81), a stable karyotype during long-term culture and could be transfected efficiently with plasmid DNA and short interfering RNA. Differentiation via formation of embryoid bodies resulted in expression of genes associated with early germ layers and terminal lineage specification. The electrophysiology of spontaneously beating NOTT1-derived cardiomyocytes was recorded and these cells were shown to be pharmacologically responsive. Histological examination of teratomas formed by in vivo differentiation of both lines in severe immunocompromised mice showed complex structures including cartilage or smooth muscle (mesoderm), luminal epithelium (endoderm) and neuroectoderm (ectoderm). These observations show that NOTT1 and NOTT2 display the accepted characteristics of hESC pluripotency.
Human Keratinocytes That Express hTERT and Also Bypass a p16INK4a-Enforced Mechanism That Limits Life Span Become Immortal yet Retain Normal Growth and Differentiation Characteristics

PubMed Central

Dickson, Mark A.; Hahn, William C.; Ino, Yasushi; Ronfard, Vincent; Wu, Jenny Y.; Weinberg, Robert A.; Louis, David N.; Li, Frederick P.; Rheinwald, James G.

2000-01-01

Normal human cells exhibit a limited replicative life span in culture, eventually arresting growth by a process termed senescence. Progressive telomere shortening appears to trigger senescence in normal human fibroblasts and retinal pigment epithelial cells, as ectopic expression of the telomerase catalytic subunit, hTERT, immortalizes these cell types directly. Telomerase expression alone is insufficient to enable certain other cell types to evade senescence, however. Such cells, including keratinocytes and mammary epithelial cells, appear to require loss of the pRB/p16INK4a cell cycle control mechanism in addition to hTERT expression to achieve immortality. To investigate the relationships among telomerase activity, cell cycle control, senescence, and differentiation, we expressed hTERT in two epithelial cell types, keratinocytes and mesothelial cells, and determined the effect on proliferation potential and on the function of cell-type-specific growth control and differentiation systems. Ectopic hTERT expression immortalized normal mesothelial cells and a premalignant, p16INK4a-negative keratinocyte line. In contrast, when four keratinocyte strains cultured from normal tissue were transduced to express hTERT, they were incompletely rescued from senescence. After reaching the population doubling limit of their parent cell strains, hTERT+ keratinocytes entered a slow growth phase of indefinite length, from which rare, rapidly dividing immortal cells emerged. These immortal cell lines frequently had sustained deletions of the CDK2NA/INK4A locus or otherwise were deficient in p16INK4a expression. They nevertheless typically retained other keratinocyte growth controls and differentiated normally in culture and in xenografts. Thus, keratinocyte replicative potential is limited by a p16INK4a-dependent mechanism, the activation of which can occur independent of telomere length. Abrogation of this mechanism together with telomerase expression immortalizes keratinocytes without affecting other major growth control or differentiation systems. PMID:10648628
Strategies for immortalization of primary hepatocytes

PubMed Central

Eva, Ramboer; Bram, De Craene; Joery, De Kock; Tamara, Vanhaecke; Geert, Berx; Vera, Rogiers; Mathieu, Vinken

2014-01-01

The liver has the unique capacity to regenerate in response to a damaging event. Liver regeneration is hereby largely driven by hepatocyte proliferation, which in turn relies on cell cycling. The hepatocyte cell cycle is a complex process that is tightly regulated by several well-established mechanisms. In vitro, isolated hepatocytes do not longer retain this proliferative capacity. However, in vitro cell growth can be boosted by immortalization of hepatocytes. Well-defined immortalization genes can be artificially overexpressed in hepatocytes or the cells can be conditionally immortalized leading to controlled cell proliferation. This paper discusses the current immortalization techniques and provides a state-of-the-art overview of the actually available immortalized hepatocyte-derived cell lines and their applications. PMID:24911463
A novel rat fibrosarcoma cell line from transformed bone marrow-derived mesenchymal stem cells with maintained in vitro and in vivo stemness properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Meng-Yu; Nestvold, Janne, E-mail: j.m.nestvold@medisin.uio.no; Rekdal, Øystein

Increasing evidence suggests a possible relationship between mesenchymal stem cells (MSCs) and sarcoma. MSCs are hypothesized to be the cells initiating sarcomagenesis, and cancer stem cells (CSCs) sharing features of MSCs have been identified in sarcomas. Here, we report on the characteristics of a bone marrow-derived rat mesenchymal stem cell line that spontaneously transformed in long-term culture. The rat transformed mesenchymal stem cells (rTMSCs) produced soft-tissue fibrosarcomas in immunocompromised mice and immunocompetent rats. In vitro, the rTMSCs displayed increased proliferation capacity compared to the untransformed cell line. The transformed MSCs maintained the mesenchymal phenotype by expression of the stem cellmore » marker CD 90 and the lack of hematopoietic and endothelial markers. Cytogenetic analysis detected trisomy 6 in the rTMSCs. Side population (SP) isolation and tumorsphere cultivation of the transformed cells confirmed the presence of CSCs among the rTMSCs. Importantly, the rTMSCs retained their differentiation capacity towards osteogenic and adipogenic lineages. This transformed MSC-based cell line may be valuable in examining the balance in a mixed cell population between cancer stem cell properties and the ability to differentiate to specific non-transformed cell populations. Moreover, it may also be a useful tool to evaluate the efficacy of novel targeted immunotherapies in vivo. - Highlights: • Spontaneously transformed rat MSCs (rTMSCs) share characteristics with normal MSCs. • rTMSCs possess a side population, enriched with tumorigenic cells. • rTMSCs model fibrosarcoma in vivo.« less
Feeder & basic fibroblast growth factor-free culture of human embryonic stem cells: Role of conditioned medium from immortalized human feeders.

PubMed

Teotia, Pooja; Sharma, Shilpa; Airan, Balram; Mohanty, Sujata

2016-12-01

Human embryonic stem cell (hESC) lines are commonly maintained on inactivated feeder cells, in the medium supplemented with basic fibroblast growth factor (bFGF). However, limited availability of feeder cells in culture, and the high cost of growth factors limit their use in scalable expansion of hESC cultures for clinical application. Here, we describe an efficient and cost-effective feeder and bFGF-free culture of hESCs using conditioned medium (CM) from immortalized feeder cells. KIND-1 hESC cell line was cultured in CM, collected from primary mouse embryonic fibroblast, human foreskin fibroblast (HFF) and immortalized HFF (I-HFF). Pluripotency of KIND-1 hESC cell line was confirmed by expression of genes, proteins and cell surface markers. In culture, these cells retained normal morphology, expressed all cell surface markers, could differentiate to embryoid bodies upon culture in vitro. Furthermore, I-HFF feeder cells without supplementation of bFGF released ample amount of endogenous bFGF to maintain stemness of hESC cells. The study results described the use of CM from immortalized feeder cells as a consistent source and an efficient, inexpensive feeder-free culture system for the maintenance of hESCs. Moreover, it was possible to maintain hESCs without exogenous supplementation of bFGF. Thus, the study could be extended to scalable expansion of hESC cultures for therapeutic purposes.
Aspects of Salt Tolerance in a NaCl-Selected Stable Cell Line of Citrus sinensis.

PubMed

Ben-Hayyim, G; Kochba, J

1983-07-01

A NaCl-tolerant cell line which was selected from ovular callus of ;Shamouti' orange (Citrus sinensis L. Osbeck) proved to be a true cell line variant. This conclusion is based on the following observations. (a) Cells which have been removed from the selection pressure for at least four passages retain the same NaCl tolerance as do cells which are kept constantly on 0.2 molar NaCl. (b) Na(+) and Cl(-) uptake are considerably lower in salt-tolerant cells (R-10) than in salt-sensitive cells (L-5) at a given external NaCl concentration. (c) Growth of salt-tolerant cells is markedly suppressed upon replacement of NaCl by KCl, whereas the growth of salt-sensitive cells is only slightly affected. Accumulation of K(+) and Cl(-) accompanies the inhibition of growth. Experiments carried out with sodium and potassium sulfate suggest that the toxic effect is due to the accumulated Cl(-). (d) Removal of Ca(2+) from the growth medium severely inhibits the growth of salt-tolerant cells in the presence of NaCl, while it has a minor effect on growth of salt-sensitive cells in the presence of NaCl. (e) Electron micrographs show that the salt-tolerant cells have very big vacuoles when exposed to salt, while the size of the vacuoles of the salt-sensitive cells does not change.
Aspects of Salt Tolerance in a NaCl-Selected Stable Cell Line of Citrus sinensis1

PubMed Central

Ben-Hayyim, Gozal; Kochba, Joshua

1983-01-01

A NaCl-tolerant cell line which was selected from ovular callus of `Shamouti' orange (Citrus sinensis L. Osbeck) proved to be a true cell line variant. This conclusion is based on the following observations. (a) Cells which have been removed from the selection pressure for at least four passages retain the same NaCl tolerance as do cells which are kept constantly on 0.2 molar NaCl. (b) Na+ and Cl− uptake are considerably lower in salt-tolerant cells (R-10) than in salt-sensitive cells (L-5) at a given external NaCl concentration. (c) Growth of salt-tolerant cells is markedly suppressed upon replacement of NaCl by KCl, whereas the growth of salt-sensitive cells is only slightly affected. Accumulation of K+ and Cl− accompanies the inhibition of growth. Experiments carried out with sodium and potassium sulfate suggest that the toxic effect is due to the accumulated Cl−. (d) Removal of Ca2+ from the growth medium severely inhibits the growth of salt-tolerant cells in the presence of NaCl, while it has a minor effect on growth of salt-sensitive cells in the presence of NaCl. (e) Electron micrographs show that the salt-tolerant cells have very big vacuoles when exposed to salt, while the size of the vacuoles of the salt-sensitive cells does not change. Images Fig. 3 PMID:16663067
Effect of sulphur mustard on human skin cell lines with differential agent sensitivity.

PubMed

Simpson, Rachel; Lindsay, Christopher D

2005-01-01

The ability of sulphur mustard (HD) to induce DNA damage places limits on the efficacy of approaches aimed at protecting human cells from the cytotoxic effects of HD using a variety of protective agents such as thiol-containing esters and protease inhibitors. In the present study, potential alternative strategies were investigated by examining the differential effects of HD on G361, SVK14, HaCaT and NCTC 2544 human skin cells. The G361 cell line was more resistant to the cytotoxic effects of HD than the NCTC, HaCaT and SVK14 cell lines at HD doses of >3 and <100 microM HD as determined by the MTT assay. At 72 h after exposure to 60 microM HD there was up to an 8.8-fold difference (P < 0.0001) between G361 and SVK14 cell culture viability. Buthionine sulphoximine (BSO) pretreatment increased the sensitivity of all four cell lines to HD. A substantial proportion of the resistance of G361 cells to HD was attributable to BSO-mediated effects on antioxidant-mediated metabolism, although G361 cultures still retained a high degree of viability at 30 microM HD following BSO pretreatment. Cell cycle analysis confirmed that SVK14 cells were relatively more sensitive to HD, as shown by the 2.1-fold reduction (P < 0.0001) in the percentage of cells in G0/G1 phase 24 h after HD exposure compared with control cultures. This compared well with a 1.2-fold increase (P < 0.05) in the percentage of G361 cells in G0/G1 phase following HD exposure, suggesting the existence of a more efficient G0/G1 checkpoint control mechanism in this cell line. Manipulation of the cell cycle using various modulating agents did not increase the resistance of cell lines to the cytotoxic effects of HD. Crown copyright 2005
Cytokeratins in normal and malignant transitional epithelium. Maintenance of expression of urothelial differentiation features in transitional cell carcinomas and bladder carcinoma cell culture lines.

PubMed Central

Moll, R.; Achtstätter, T.; Becht, E.; Balcarova-Ständer, J.; Ittensohn, M.; Franke, W. W.

1988-01-01

The pattern of cytokeratins expressed in normal urothelium has been compared with that of various forms of transitional cell carcinomas (TCCs; 21 cases) and cultured bladder carcinoma cell lines, using immunolocalization and gel electrophoretic techniques. In normal urothelium, all simple-epithelium-type cytokeratins (polypeptides 7, 8, 18, 19) were detected in all cell layers, whereas antibodies to cytokeratins typical for stratified epithelia reacted with certain basal cells only or, in the case of cytokeratin 13, with cells of the basal and intermediate layers. This pattern was essentially maintained in low-grade (G1, G1/2) TCCs but was remarkably modified in G2 TCCs. In G3 TCCs simple-epithelial cytokeratins were predominant whereas the amounts of component 13 were greatly reduced. Squamous metaplasia was accompanied generally by increased or new expression of some stratified-epithelial cytokeratins. The cytokeratin patterns of cell culture lines RT-112 and RT-4 resembled those of G1 and G2 TCCs, whereas cell line T-24 was comparable to G3 carcinomas. The cell line EJ showed a markedly different pattern. The results indicate that, in the cell layers of the urothelium, the synthesis of stratification-related cytokeratins such as component 13 is inversely oriented compared with that in other stratified epithelia where these proteins are suprabasally expressed, that TCCs retain certain intrinsic cytoskeletal features of urothelium, and that different TCCs can be distinguished by their cytokeratin patterns. The potential value of these observations in histopathologic and cytologic diagnoses is discussed. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 PMID:2456018
TPA induces a block of differentiation and increases the susceptibility to neoplastic transformation of a rat thyroid epithelial cell line.

PubMed

Portella, G; Vitagliano, D; Li, Z; Sferratore, F; Santoro, M; Vecchio, G; Fusco, A

1998-01-01

The PC Cl 3 cell line is a well-characterized epithelial cell line of rat thyroid origin. This cell line retains in vitro the typical markers of thyroid differentiation: thyroglobulin (TG) synthesis and secretion, iodide uptake, thyroperoxidase (TPO) expression, and dependency on TSH for growth. Although the differentiated phenotype of thyroid cells has been relatively well described, the molecular mechanisms that regulate both differentiation and neoplastic transformation of thyroid cells still need to be investigated in detail. Protein kinase C (PKC), the target of tetradecanoylphorbol acetate (TPA), regulates growth and differentiation of several cell types. Here we show that treatment of PC Cl 3 cells with TPA induces an acute block of thyroid differentiation. TPA-treated PC Cl 3 cells are unable to trap iodide and the expression levels of thyroglobulin, TSH receptor, and TPO genes are drastically reduced by TPA treatment. This differentiation block is not caused by a reduced expression of one of the master genes of thyroid differentiation, the thyroid transcription factor 1 (TTF-1). TPA-treated PC Cl 3 cells display an increased growth rate indicating that, in addition to the differentiation block, TPA also significantly affects the growth regulation of thyroid cells. Finally, TPA treatment dramatically increases the number of transformation foci induced in PC Cl 3 cells by retroviruses carrying v-Ki-ras, v-Ha-ras, and v-mos oncogenes. These findings support the notion that the PKC pathway can influence proliferation, differentiation, and neoplastic transformation of thyroid cells in culture.
Fuel cell cassette with compliant seal

DOEpatents

Karl, Haltiner, Jr. J.; Anthony, Derose J.; Klotzbach, Darasack C.; Schneider, Jonathan R.

2017-11-07

A fuel cell cassette for forming a fuel cell stack along a fuel cell axis includes a cell retainer, a plate positioned axially to the cell retainer and defining a space axially with the cell retainer, and a fuel cell having an anode layer and a cathode layer separated by an electrolyte layer. The outer perimeter of the fuel cell is positioned in the space between the plate and the cell retainer, thereby retaining the fuel cell and defining a cavity between the cell retainer, the fuel cell, and the plate. The fuel cell cassette also includes a seal disposed within the cavity for sealing the edge of the fuel cell. The seal is compliant at operational temperatures of the fuel cell, thereby allowing lateral expansion and contraction of the fuel cell within the cavity while maintaining sealing at the edge of the fuel cell.

Isolation and characterization of an IGROV-1 human ovarian cancer cell line made resistant to Ecteinascidin-743 (ET-743)

PubMed Central

Erba, E; Bergamaschi, D; Bassano, L; Ronzoni, S; Liberti, G Di; Muradore, I; Vignati, S; Faircloth, G; Jimeno, J; D'Incalci, M

2000-01-01

By exposing Igrov-1 human ovarian cancer cells to increasing concentrations of Ecteinascidin-743 (ET-743), either for a short or prolonged time, we obtained sublines resistant to ET-743 which overexpress Pgp. The most resistant clone (Igrov-1/25 ET) was evaluated for biological and pharmacological characterizations. The increased Pgp levels of Igrov-1/25 ET were not due to amplification of the mdr-1 gene but to increased mRNA levels. No increase in other multidrug resistance-related proteins such as MRP or LRP was observed in Igrov-1/25 ET. The IC50values of ET-743 against Igrov-1/25 ET was approximately 50 times higher than the parental cell line. Resistance was not reversed while maintaining the cell line in drug-free medium for at least 24 months. Igrov-1/25 ET was cross-resistant to Doxorubicin and VP16 while it was equally sensitive to L-PAM, MNNG, CPT and only marginally less sensitive to Cis-DDP and Oxaliplatin compared to the parental cell line. Igrov-1/25 ET exposed to Doxorubicin retained this drug much less, mainly because of a more efficient drug efflux. The cyclosporine analogue SDZ PSC-833 reversed the resistance of Igrov-1/25 ET to ET-743, without any enhancement of the drug activity against the parental Igrov-1 cell line. Igrov-1/25 ET exhibits typical features of cell lines overexpressing the mdr-1 gene and can be a potentially useful tool in selecting ET-743 non-cross-resistant analogues as well as to investigate methods to counteract resistance to this drug. © 2000 Cancer Research Campaign PMID:10817511
CRISPR/Cas9 knockout of HAS2 in rat chondrosarcoma chondrocytes demonstrates the requirement of hyaluronan for aggrecan retention

PubMed Central

Huang, Yi; Askew, Emily B.; Knudson, Cheryl B.; Knudson, Warren

2016-01-01

Hyaluronan (HA) plays an essential role in cartilage where it functions to retain aggrecan. Previous studies have suggested that aggrecan is anchored indirectly to the plasma membrane of chondrocytes via its binding to cell-associated HA. However, reagents used to test these observations such as hyaluronidase and HA oligosaccharides are short term and may have side activities that complicate interpretation. Using the CRISPR/Cas9 gene editing approach, a model system was developed by generating HA-deficient chondrocyte cell lines. HA synthase-2 (Has2)-specific single guide RNA was introduced into two different variant lines of rat chondrosarcoma chondrocytes; knockout clones were isolated and characterized. Two other members of the HA synthase gene family were expressed at very low relative copy number but showed no compensatory response in the Has2 knockouts. Wild type chondrocytes of both variants exhibited large pericellular matrices or coats extending from the plasma membrane. Addition of purified aggrecan monomer expanded the size of these coats as the proteoglycan became retained within the pericellular matrix. Has2 knockout chondrocytes lost all capacity to assemble a particle-excluding pericellular matrix and more importantly, no matrices formed around the knockout cells following the addition of purified aggrecan. When grown as pellet cultures so as to generate a bioengineered neocartilage tissue, the Has2 knockout chondrocytes assumed a tightly-compacted morphology as compared to the wild type cells. When knockout chondrocytes were transduced with Adeno-ZsGreen1-mycHas2, the cell-associated pericellular matrices were restored including the capacity to bind and incorporate additional exogenous aggrecan into the matrix. These results suggest that HA is essential for aggrecan retention and maintaining cell separation during tissue formation. PMID:27094859
75 FR 51519 - Regional Transportation District-Acquisition Exemption-Union Pacific Railroad Company in Adams...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-20

... County, Colo. (the Gold Line Segment).\\2\\ RTD states that, on both segments, UP will retain the remaining... construction and operation of RTD's facilities. RTD states that, on the Gold Line Segment, UP will retain the... freight service on both the East Corridor Segment and the Gold Line Segment. \\1\\ RTD is a political...
Expression profiling of G-protein-coupled receptors in human urothelium and related cell lines.

PubMed

Ochodnický, Peter; Humphreys, Sian; Eccles, Rachel; Poljakovic, Mirjana; Wiklund, Peter; Michel, Martin C

2012-09-01

What's known on the subject? and What does the study add? Urothelium emerged as a crucial integrator of sensory inputs and outputs in the bladder wall, and urothelial G-protein-coupled receptors (GPCRs) may represent plausible targets for treatment of various bladder pathologies. Urothelial cell lines provide a useful tool to study urothelial receptor function, but their validity as models for native human urothelium remains unclear. We characterize the mRNA expression of genes coding for GPCRs in human freshly isolated urothelium and compare the expression pattern with those in human urothelial cell lines. To characterize the mRNA expression pattern of genes coding for G-protein-coupled receptors (GPCRs) in human freshly isolated urothelium. To compare GPCR expression in human urothelium-derived cell lines to explore the suitability of these cell lines as model systems to study urothelial function. Native human urothelium (commercially sourced) and human urothelium-derived non-cancer (UROtsa and TERT-NHUC) and cancer (J82) cell lines were used. For mRNA expression profiling we used custom-designed real-time polymerase chain reaction array for 40 receptors and several related genes. Native urothelium expressed a wide variety of GPCRs, including α(1A), α(1D) and all subtypes of α(2) and β adrenoceptors. In addition, M(2) and M(3) cholinergic muscarinic receptors, angiotensin II AT(1) receptor, serotonin 5-HT(2A) receptor and all subtypes of bradykinin, endothelin, cannabinoid, tachykinin and sphingosine-1-phosphate receptors were detected. Nerve growth factor and both its low- and high-affinity receptors were also expressed in urothelium. In all cell lines expression of most GPCRs was markedly downregulated, with few exceptions. In UROtsa cells, but much less in other cell lines, the expression of β(2) adrenoceptors, M(3) muscarinic receptors, B(1) and B(2) bradykinin receptors, ET(B) endothelin receptors and several subtypes of sphingosine-1-phosphate receptors was largely retained. Human urothelium expresses a wide range of receptors which enables sensing and integration of various extracellular signals. Human urothelium-derived cell lines, especially UROtsa cells, show comparable mRNA expression to native tissue for several physiologically relevant GPCRs, but lose expression of many other receptors. The use of cell lines as model systems of human urothelium requires careful validation of suitability for the genes of interest. © 2012 BJU INTERNATIONAL.
Presence of infectious RD-114 virus in a proportion of canine parvovirus isolates.

PubMed

Yoshikawa, Rokusuke; Sato, Eiji; Miyazawa, Takayuki

2012-03-01

We recently found that certain canine live attenuated vaccines produced using `non-feline' cell lines were contaminated with an infectious feline endogenous retrovirus, termed RD-114 virus. We suspected that RD-114 virus may have contaminated the seed stock of canine parvovirus (CPV) during the production of the contaminated vaccines. In this study, we collected stock viruses of CPVs propagated in a feline cell line, and checked the presence of infectious RD-114 virus. Consequently, we found that RD-114 viral RNA was present in all stock viruses, and 7 out of 18 stock viruses were contaminated with infectious RD-114 virus. We also found that RD-114 virus was stable physically and is capable of retaining its infectivity for a long period at -80°C.
A simple non-perturbing cell migration assay insensitive to proliferation effects.

PubMed

Glenn, Honor L; Messner, Jacob; Meldrum, Deirdre R

2016-08-18

Migration is a fundamental cellular behavior that plays an indispensable role in development and homeostasis, but can also contribute to pathology such as cancer metastasis. Due to its relevance to many aspects of human health, the ability to accurately measure cell migration is of broad interest, and numerous approaches have been developed. One of the most commonly employed approaches, because of its simplicity and throughput, is the exclusion zone assay in which cells are allowed to migrate into an initially cell-free region. A major drawback of this assay is that it relies on simply counting cells in the exclusion zone and therefore cannot distinguish the effects of proliferation from migration. We report here a simple modification to the exclusion zone migration assay that exclusively measures cell migration and is not affected by proliferation. This approach makes use of a lineage-tracing vital stain that is retained through cell generations and effectively reads out migration relative to the original, parental cell population. This modification is simple, robust, non-perturbing, and inexpensive. We validate the method in a panel of cell lines under conditions that inhibit or promote migration and demonstrate its use in normal and cancer cell lines as well as primary cells.
Production of human monoclonal IgG antibodies against Rhesus (D) antigen.

PubMed Central

Bron, D; Feinberg, M B; Teng, N N; Kaplan, H S

1984-01-01

An Epstein-Barr virus (EBV)-transformed human B-cell line ( LB4r ) producing anti-Rhesus [Rho(D) antigen] antibody was fused with a non-immunoglobulin-producing mouse-human heteromyeloma ( SHM - D33 ) and selected in hypoxanthine/aminopterin/thymidine medium containing 0.5 microM ouabain. Surviving hybrids found to secrete specific anti-Rho(D) antibody were cloned by limiting dilution. Two clones (D4-B2 and E10-C1) producing high levels (12 and 20 micrograms/ml per 10(6) cells per 24 hr, respectively) of monospecific antibody (IgG3, lambda chain) were selected for expansion and further characterization. Compared to the parental cell line ( LB4r ), these hybridoma cell lines presented several advantages: antibody production was increased 10-fold, cloning efficiency was improved, and the EBV genome was not retained. Antibody production has been stable for greater than 8 months. These human monoclonal anti-Rho(D) antibodies have demonstrated utility in routine blood-group typing. They may also prove useful in the biochemical and genetic characterization of the Rh antigen system. Most important, they offer a source of Rh-immune globulin for the prevention of Rh immunization and alloimmune hemolytic disease of the newborn. Images PMID:6427767
Enhancing wear resistance of working bodies of grinder through lining crushed material

NASA Astrophysics Data System (ADS)

Romanovich, A. A.; Annenko, D. M.; Romanovich, M. A.; Apukhtina, I. V.

2018-03-01

The article presents the analysis of directions of increasing wear resistance of working surfaces of rolls. A technical solution developed at the level of the invention is proposed, which is simple to implement in production conditions and which makes it possible to protect the roll surface from heavy wear due to surfacing of wear-resistant mesh material, cells of which are filling with grinding material in the process of work. Retaining them enables one to protect the roll surface from wear. The paper dwells on conditions of pressing materials in cells of eccentric rolls on the working surface with a grid of rectangular shape. The paper presents an equation for calculation of the cell dimension that provides the lining of the working surface by a mill material with respect to its properties. The article presents results of comparative studies on the grinding process of a press roller grinder (PRG) between rolls with and without a fusion-bonded mesh. It is clarified that the lining of rolls working surface slightly reduces the quality of the grinding, since the material thickness in the cell is small and has a finely divided and compacted structure with high strength.
Cryopreservation of Human Stem Cells for Clinical Application: A Review

PubMed Central

Hunt, Charles J.

2011-01-01

Summary Stem cells have been used in a clinical setting for many years. Haematopoietic stem cells have been used for the treatment of both haematological and non-haematological disease; while more recently mesenchymal stem cells derived from bone marrow have been the subject of both laboratory and early clinical studies. Whilst these cells show both multipotency and expansion potential, they nonetheless do not form stable cell lines in culture which is likely to limit the breadth of their application in the field of regenerative medicine. Human embryonic stem cells are pluripotent cells, capable of forming stable cell lines which retain the capacity to differentiate into cells from all three germ layers. This makes them of special significance in both regenerative medicine and toxicology. Induced pluripotent stem (iPS) cells may also provide a similar breadth of utility without some of the confounding ethical issues surrounding embryonic stem cells. An essential pre-requisite to the commercial and clinical application of stem cells are suitable cryopreservation protocols for long-term storage. Whilst effective methods for cryopreservation and storage have been developed for haematopoietic and mesenchymal stem cells, embryonic cells and iPS cells have proved more refractory. This paper reviews the current state of cryopreservation as it pertains to stem cells and in particular the embryonic and iPS cell. PMID:21566712
Cryopreservation of Human Stem Cells for Clinical Application: A Review.

PubMed

Hunt, Charles J

2011-01-01

SUMMARY: Stem cells have been used in a clinical setting for many years. Haematopoietic stem cells have been used for the treatment of both haematological and non-haematological disease; while more recently mesenchymal stem cells derived from bone marrow have been the subject of both laboratory and early clinical studies. Whilst these cells show both multipotency and expansion potential, they nonetheless do not form stable cell lines in culture which is likely to limit the breadth of their application in the field of regenerative medicine. Human embryonic stem cells are pluripotent cells, capable of forming stable cell lines which retain the capacity to differentiate into cells from all three germ layers. This makes them of special significance in both regenerative medicine and toxicology. Induced pluripotent stem (iPS) cells may also provide a similar breadth of utility without some of the confounding ethical issues surrounding embryonic stem cells. An essential pre-requisite to the commercial and clinical application of stem cells are suitable cryopreservation protocols for long-term storage. Whilst effective methods for cryopreservation and storage have been developed for haematopoietic and mesenchymal stem cells, embryonic cells and iPS cells have proved more refractory. This paper reviews the current state of cryopreservation as it pertains to stem cells and in particular the embryonic and iPS cell.
Cafestol, a diterpene molecule found in coffee, induces leukemia cell death.

PubMed

Lima, Cauê S; Spindola, Daniel G; Bechara, Alexandre; Garcia, Daniel M; Palmeira-Dos-Santos, Caroline; Peixoto-da-Silva, Janaina; Erustes, Adolfo G; Michelin, Luis F G; Pereira, Gustavo J S; Smaili, Soraya S; Paredes-Gamero, Edgar; Calgarotto, Andrana K; Oliveira, Carlos R; Bincoletto, Claudia

2017-08-01

To evaluate the antitumor properties of Cafestol four leukemia cell lines were used (NB4, K562, HL60 and KG1). Cafestol exhibited the highest cytotoxicity against HL60 and KG1 cells, as evidenced by the accumulation of cells in the sub-G1 fraction, mitochondrial membrane potential reduction, accumulation of cleaved caspase-3 and phosphatidylserine externalization. An increase in CD11b and CD15 differentiation markers with attenuated ROS generation was also observed in Cafestol-treated HL60 cells. These results were similar to those obtained following exposure of the same cell line to cytarabine (Ara-C), an antileukemic drug. Cafestol and Ara-C reduced the clonogenic potential of HL60 cells by 100%, but Cafestol spared murine colony forming unit- granulocyte/macrophage (CFU-GM), which retained their clonogenicity. The co-treatment of Cafestol and Ara-C reduced HL60 cell viability compared with both drugs administered alone. In conclusion, despite the distinct molecular mechanisms involved in the activity of Cafestol and Ara-C, a similar cytotoxicity towards leukemia cells was observed, which suggests a need for prophylactic-therapeutic pre-clinical studies regarding the anticancer properties of Cafestol. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Factors that facilitate registered nurses in their first-line nurse manager role.

PubMed

Cziraki, Karen; McKey, Colleen; Peachey, Gladys; Baxter, Pamela; Flaherty, Brenda

2014-11-01

To determine the factors that attract and retain Registered Nurses in the first-line nurse manager role. The first-line nurse manger role is pivotal in health-care organisations. National demographics suggest that Canada will face a first-line nurse manager shortage because of retirement in the next decade. Determination of factors that attract and retain Registered Nurses will assist organisations and policy makers to employ strategies to address this shortage. The study used an exploratory, descriptive qualitative approach, consisting of semi-structured individual interviews with 11 Registered Nurses in first-line nurse manager roles. The findings revealed a discrepancy between the factors that attract and retain Registered Nurses in the first-line nurse manager role, underscored the importance of the mentor role and confirmed the challenges encountered by first-line nurse managers practicing in the current health-care environment. The first-line nurse manager role has been under studied. Further research is warranted to understand which strategies are most effective in supporting first-line nurse managers. Strategies to support nurses in the first-line nurse manager role are discussed for the individual, programme, organisation and health-care system/policy levels. © 2013 John Wiley & Sons Ltd.
Generation of SNCA Cell Models Using Zinc Finger Nuclease (ZFN) Technology for Efficient High-Throughput Drug Screening.

PubMed

Dansithong, Warunee; Paul, Sharan; Scoles, Daniel R; Pulst, Stefan M; Huynh, Duong P

2015-01-01

Parkinson's disease (PD) is a progressive neurodegenerative disorder caused by loss of dopaminergic neurons of the substantia nigra. The hallmark of PD is the appearance of neuronal protein aggregations known as Lewy bodies and Lewy neurites, of which α-synuclein forms a major component. Familial PD is rare and is associated with missense mutations of the SNCA gene or increases in gene copy number resulting in SNCA overexpression. This suggests that lowering SNCA expression could be therapeutic for PD. Supporting this hypothesis, SNCA reduction was neuroprotective in cell line and rodent PD models. We developed novel cell lines expressing SNCA fused to the reporter genes luciferase (luc) or GFP with the objective to enable high-throughput compound screening (HTS) for small molecules that can lower SNCA expression. Because SNCA expression is likely regulated by far-upstream elements (including the NACP-REP1 located at 8852 bp upstream of the transcription site), we employed zinc finger nuclease (ZFN) genome editing to insert reporter genes in-frame downstream of the SNCA gene in order to retain native SNCA expression control. This ensured full retention of known and unknown up- and downstream genetic elements controlling SNCA expression. Treatment of cells with the histone deacetylase inhibitor valproic acid (VPA) resulted in significantly increased SNCA-luc and SNCA-GFP expression supporting the use of our cell lines for identifying small molecules altering complex modes of expression control. Cells expressing SNCA-luc treated with a luciferase inhibitor or SNCA siRNA resulted in Z'-scores ≥ 0.75, suggesting the suitability of these cell lines for use in HTS. This study presents a novel use of genome editing for the creation of cell lines expressing α-synuclein fusion constructs entirely under native expression control. These cell lines are well suited for HTS for compounds that lower SNCA expression directly or by acting at long-range sites to the SNCA promoter and 5'-UTR.
TGF-β signaling is often attenuated during hepatotumorigenesis, but is retained for the malignancy of hepatocellular carcinoma cells.

PubMed

Mu, Xiaoxin; Lin, Shu; Yang, Junhua; Chen, Chen; Chen, Yun; Herzig, Maryanne C; Washburn, Kenneth; Halff, Glenn A; Walter, Christi A; Sun, Beicheng; Sun, Lu-Zhe

2013-01-01

The role of transforming growth factor-beta (TGF-β) signaling in hepatocarcinogenesis remains controversial. We aimed to reveal TGF-β signaling status in human and murine tissues of hepatocellular carcinoma (HCC) and the mechanisms that mediate TGF-β's role in regulating HCC malignancy. Here, TGF-β pathway component expression and activation in human and murine HCC tissues were measured with quantitative RT-PCR and Western blotting assays. The role of TGF-β receptor and Smad signaling in the growth and survival of several HCC cell lines was determined with several in vitro and in vivo approaches. We found that TGF-β receptor II (TβRII) expression was downregulated in two different HCC patient cohorts. Consistently, Smad3 phosphorylation was also downregulated in HCC tissues in comparison to that in adjacent normal tissues. Interestingly, many HCC cell lines were sensitive to TGF-β and growth-inhibited by exogenous TGF-β. However, stable knockdown of TβRII inhibited cell growth on plastic and in soft agar, and induced apoptosis resulting in suppressed subcutaneous tumor growth and metastatic potential in vivo. Furthermore, knockdown of Smad4 also led to a significant inhibition of growth on plastic and in soft agar with concomitant increase of apoptosis, PTEN expression, and reduced nuclear accumulation of linker region-phosphorylated Smad3. Taken together, TGF-β signaling pathway plays a dichotomous role in hepatocellular carcinogenesis. It appears to suppress HCC development, but is retained for HCC cell survival and malignancy. Furthermore, Smad4 can mediate both growth inhibitory activity induced by exogenous TGF-β and the survival activity induced by autocrine TGF-β revealing a delicate selection of the two opposing activities of TGF-β during HCC evolution.
Isolated Anxa5{sup +}/Sca-1{sup +} perivascular cells from mouse meningeal vasculature retain their perivascular phenotype in vitro and in vivo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brachvogel, Bent; Pausch, Friederike; Farlie, Peter

2007-07-15

Pericytes are closely associated with endothelial cells, contribute to vascular stability and represent a potential source of mesenchymal progenitor cells. Using the specifically expressed annexin A5-LacZ fusion gene (Anxa5-LacZ), it became possible to isolate perivascular cells (PVC) from mouse tissues. These cells proliferate and can be cultured without undergoing senescence for multiple passages. PVC display phenotypic characteristics of pericytes, as they express pericyte-specific markers (NG2-proteoglycan, desmin, {alpha}SMA, PDGFR-{beta}). They also express stem cell marker Sca-1, whereas endothelial (PECAM), hematopoietic (CD45) or myeloid (F4/80, CD11b) lineage markers are not detectable. These characteristics are in common with the pericyte-like cell line 10T1/2.more » PVC also display a phagocytoic activity higher than 10T1/2 cells. During coculture with endothelial cells both cell types stimulate angiogenic processes indicated by an increased expression of PECAM in endothelial cells and specific deposition of basement membrane proteins. PVC show a significantly increased induction of endothelial specific PECAM expression compared to 10T1/2 cells. Accordingly, in vivo grafts of PVC aggregates onto chorioallantoic membranes of quail embryos recruit endothelial cells, get highly vascularized and deposit basement membrane components. These data demonstrate that isolated Anxa5-LacZ{sup +} PVC from mouse meninges retain their capacity for differentiation to pericyte-like cells and contribute to angiogenic processes.« less
Oncolytic Activity of Avian Influenza Virus in Human Pancreatic Ductal Adenocarcinoma Cell Lines

PubMed Central

Pizzuto, Matteo S.; Silic-Benussi, Micol; Pavone, Silvia; Ciminale, Vincenzo; Capua, Ilaria

2014-01-01

ABSTRACT Pancreatic ductal adenocarcinoma (PDA) is the most lethal form of human cancer, with dismal survival rates due to late-stage diagnoses and a lack of efficacious therapies. Building on the observation that avian influenza A viruses (IAVs) have a tropism for the pancreas in vivo, the present study was aimed at testing the efficacy of IAVs as oncolytic agents for killing human PDA cell lines. Receptor characterization confirmed that human PDA cell lines express the alpha-2,3- and the alpha-2,6-linked glycan receptor for avian and human IAVs, respectively. PDA cell lines were sensitive to infection by human and avian IAV isolates, which is consistent with this finding. Growth kinetic experiments showed preferential virus replication in PDA cells over that in a nontransformed pancreatic ductal cell line. Finally, at early time points posttreatment, infection with IAVs caused higher levels of apoptosis in PDA cells than gemcitabine and cisplatin, which are the cornerstone of current therapies for PDA. In the BxPC-3 PDA cell line, apoptosis resulted from the engagement of the intrinsic mitochondrial pathway. Importantly, IAVs did not induce apoptosis in nontransformed pancreatic ductal HPDE6 cells. Using a model based on the growth of a PDA cell line as a xenograft in SCID mice, we also show that a slightly pathogenic avian IAV significantly inhibited tumor growth following intratumoral injection. Taken together, these results are the first to suggest that IAVs may hold promise as future agents of oncolytic virotherapy against pancreatic ductal adenocarcinomas. IMPORTANCE Despite intensive studies aimed at designing new therapeutic approaches, PDA still retains the most dismal prognosis among human cancers. In the present study, we provide the first evidence indicating that avian IAVs of low pathogenicity display a tropism for human PDA cells, resulting in viral RNA replication and a potent induction of apoptosis in vitro and antitumor effects in vivo. These results suggest that slightly pathogenic IAVs may prove to be effective for oncolytic virotherapy of PDA and provide grounds for further studies to develop specific and targeted viruses, with the aim of testing their efficacy in clinical contexts. PMID:24899201
A novel, immortal, and multipotent human neural stem cell line generating functional neurons and oligodendrocytes.

PubMed

De Filippis, Lidia; Lamorte, Giuseppe; Snyder, Evan Y; Malgaroli, Antonio; Vescovi, Angelo L

2007-09-01

The discovery and study of neural stem cells have revolutionized our understanding of the neurogenetic process, and their inherent ability to adopt expansive growth behavior in vitro is of paramount importance for the development of novel therapeutics based on neural cell replacement. Recent advances in high-throughput assays for drug development and gene discovery dictate the need for rapid, reproducible, long-term expansion of human neural stem cells (hNSCs). In this view, the complement of wild-type cell lines currently available is insufficient. Here we report the establishment of a stable human neural stem cell line (immortalized human NSCs [IhNSCs]) by v-myc-mediated immortalization of previously derived wild-type hNSCs. These cells demonstrate three- to fourfold faster proliferation than wild-type cells in response to growth factors but retain rather similar properties, including multipotentiality. By molecular biology, biochemistry, immunocytochemistry, fluorescence microscopy, and electrophysiology, we show that upon growth factor removal, IhNSCs completely downregulate v-myc expression, cease proliferation, and differentiate terminally into three major neural lineages: astrocytes, oligodendrocytes, and neurons. The latter are functional, mature cells displaying clear-cut morphological and physiological features of terminally differentiated neurons, encompassing mostly the GABAergic, glutamatergic, and cholinergic phenotypes. Finally, IhNSCs produce bona fide oligodendrocytes in fractions up to 20% of total cell number. This is in contrast to the negligible propensity of hNSCs to generate oligodendroglia reported so far. Thus, we describe an immortalized hNSC line endowed with the properties of normal hNSCs and suitable for developing the novel, reliable assays and reproducible high-throughput gene and drug screening that are essential in both diagnostics and cell therapy studies.
Optimization of in vitro inhibition of HT-29 colon cancer cell cultures by Solanum tuberosum L. extracts.

PubMed

Zuber, T; Holm, D; Byrne, P; Ducreux, L; Taylor, M; Kaiser, M; Stushnoff, C

2015-01-01

Secondary metabolites in potato have been reported to possess bioactive properties, including growth inhibition of cancer cells. Because potatoes are widely consumed globally, potential health benefits may have broad application. Thus we investigated growth inhibition of HT-29 colon cancer cell cultures by extracts from 13 diverse genetic breeding clones. Extracts from three pigmented selections (CO97226-2R/R, CO97216-1P/P, CO04058-3RW/RW) inhibited growth of in vitro HT-29 cell cultures more effectively than other clones tested. While inhibition was highest from pigmented selections and pigmented tuber tissue sectors, not all pigmented breeding lines tested had appreciable inhibitory properties. Thus, inhibition was not uniquely linked to pigmentation. Immature tubers had the highest inhibitory properties, and in most cases mature tubers retained very low inhibition properties. Flowers and skins inhibited strongly at lower extract concentrations. An extract consisting of 7.2 mg mL⁻¹ cell culture medium was the lowest effective concentration. While raw tuber extracts inhibited most effectively, a few clones at higher concentrations retained inhibition after cooking. Heated whole tubers retained higher inhibition than heated aqueous extracts. While all aqueous extracts from the two tuber selections (CO97216-1P/P and CO97226-2R/R) inhibited HT-29 cell cultures, inhibition was significantly enhanced in purple pigmented tubers of CO97216-1P/P prepared cryogenically as liquid nitrogen powders compared to extracts from freeze dried samples. Upregulation of caspase-3 protease activity, indicative of apoptosis, was highest among the most inhibitory clone samples. The unique sectorial red pigment expressing selection (CO04058-3RW/RW) provided a model system that isolated expression in pigmented sectors, and thus eliminated developmental, environmental and genetic confounding.
Simultaneous knock-down of six β-galactosidase genes in petunia petals prevents loss of pectic galactan but decreases petal strength.

PubMed

O'Donoghue, Erin M; Somerfield, Sheryl D; Deroles, Simon C; Sutherland, Paul W; Hallett, Ian C; Erridge, Zoë A; Brummell, David A; Hunter, Donald A

2017-04-01

Galactose (Gal) is incorporated into cell wall polysaccharides as flowers open, but then is lost because of β-galactosidase activity as flowers mature and wilt. The significance of this for flower physiology resides in the role of galactan-containing polysaccharides in the cell wall, which is still largely unresolved. To investigate this, transcript accumulation of six cell wall-associated β-galactosidases was simultaneously knocked down in 'Mitchell' petunia (Petunia axillaris x (P. axillaris x P. hybrida)) flower petals. The multi-PhBGAL RNAi construct targeted three bud- and three senescence-associated β-galactosidase genes. The petals of the most down-regulated line (GA19) were significantly disrupted in galactose turnover during flower opening, and at the onset of senescence had retained 86% of their galactose compared with 20% in the controls. The Gal content of Na 2 CO 3 -soluble cell wall extracts and the highly insoluble polysaccharides associated with cellulose were particularly affected. Immunodetection with the antibody LM5 showed that much of the cell wall Gal in GA19 was retained as galactan, presumably the side-chains of rhamnogalacturonan-I. The flowers of GA19, despite having retained substantially more galactan, were no different from controls in their internal cell arrangement, dimensions, weight or timing of opening and senescence. However, the GA19 petals had less petal integrity (as judged by force required to cause petal fracture) after opening and showed a greater decline in this integrity with time than controls, raising the possibility that galactan loss is a mechanism for helping to maintain petal tissue cohesion after flower opening. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
The effect of porphyrins on normal and transformed mouse cell lines in the presence of visible light.

PubMed

Tita, S P; Perussi, J R

2001-10-01

Photodynamic therapy consists of the uptake of a photosensitizing dye, often a porphyrin, by tumor tissue and subsequent irradiation of the tumor with visible light of an appropriate wavelength matched to the absorption spectrum of the photosensitizing dye. This class of molecules produces reactive oxygen species when activated by light, resulting in a direct or indirect cytotoxic effect on the target cells. Photodynamic therapy has been used in the treatment of cancer but the technology has a potential for the treatment of several disease conditions mainly because of its selectivity. However, it is not clear why the porphyrins are retained preferentially by abnormal tissue. This paper describes a study of the effect of the association of porphyrin and visible light on two mouse fibroblast cell lines: A31, normal cells and B61, an EJ-ras transformed variant of A31. Two water-soluble porphyrins were used, a positively charged one, tetra(N-methyl-4-pyridyl)porphyrin chloride, and a negatively charged one, tetra(4-sulfonatophenyl)porphyrin-Na salt (TPPS4) in order to assess the effect on cell survival. The results suggest that the B61 cell line is more sensitive to incubation with the anionic porphyrin (TPPS4) followed by light irradiation and that the anionic porphyrin is more efficient in killing the cells than the cationic porphyrin.

Regulation of aromatase activity in bone-derived cells: possible role of mitogen-activated protein kinase.

PubMed

Shozu, M; Sumitani, H; Murakami, K; Segawa, T; Yang, H J; Inoue, M

2001-12-01

Fetal human osteoblast-like cells and the THP-1 cell line that differentiates into macrophage/osteoblast-like cells in the presence of Vitamin D3 and which possesses high aromatase activity, constitute a useful model with which to study the regulation of aromatase in bone. We showed that dexamethasone (DEX)-induced aromatase activity in the THP-1 cell line is completely suppressed by forskolin and by dibutyryl cAMP. We therefore investigated the contribution of mitogen-activated protein kinase (MAPK) to the regulation of aromatase, because cAMP inhibits MAPK in many cells. We examined the role of MAPK on aromatase activity using PD98059, a selective inhibitor of MEK-1. PD98059 (100 microM) reduced DEX+interleukin (IL)-1beta-induced aromatase activity in human osteoblast-like cells by more than 90%, whereas 50% of the aromatase mRNA concentration was retained compared with the control incubated with DEX+IL-1beta. PD98059 (50 microM) reduced the activity of aromatase in THP-1 cells by 80% without significantly affecting the mRNA level. These results indicated that MAPK plays an important role in aromatase activation at the post-transcriptional level.
A Rapid Filter Insert-based 3D Culture System for Primary Prostate Cell Differentiation

PubMed Central

Tricoli, Lucas; Berry, Deborah L.; Albanese, Chris

2018-01-01

Conditionally reprogrammed cells (CRCs) provide a sustainable method for primary cell culture and the ability to develop extensive “living biobanks” of patient derived cell lines. For many types of epithelial cells, various three dimensional (3D) culture approaches have been described that support an improved differentiated state. While CRCs retain their lineage commitment to the tissue from which they are isolated, they fail to express many of the differentiation markers associated with the tissue of origin when grown under normal two dimensional (2D) culture conditions. To enhance the application of patient-derived CRCs for prostate cancer research, a 3D culture format has been defined that enables a rapid (2 weeks total) luminal cell differentiation in both normal and tumor-derived prostate epithelial cells. Herein, a filter insert-based format is described for the culturing and differentiation of both normal and malignant prostate CRCs. A detailed description of the procedures required for cell collection and processing for immunohistochemical and immunofluorescent staining are provided. Collectively the 3D culture format described, combined with the primary CRC lines, provides an important medium- to high- throughput model system for biospecimen-based prostate research. PMID:28287583
Constitutive Activation of PINK1 Protein Leads to Proteasome-mediated and Non-apoptotic Cell Death Independently of Mitochondrial Autophagy*

PubMed Central

Akabane, Shiori; Matsuzaki, Kohei; Yamashita, Shun-ichi; Arai, Kana; Okatsu, Kei; Kanki, Tomotake; Matsuda, Noriyuki; Oka, Toshihiko

2016-01-01

Phosphatase and tensin homolog-induced putative kinase 1 (PINK1), a Ser/Thr kinase, and PARKIN, a ubiquitin ligase, are causal genes for autosomal recessive early-onset parkinsonism. Multiple lines of evidence indicate that PINK1 and PARKIN cooperatively control the quality of the mitochondrial population via selective degradation of damaged mitochondria by autophagy. Here, we report that PINK1 and PARKIN induce cell death with a 12-h delay after mitochondrial depolarization, which differs from the time profile of selective autophagy of mitochondria. This type of cell death exhibited definite morphologic features such as plasma membrane rupture, was insensitive to a pan-caspase inhibitor, and did not involve mitochondrial permeability transition. Expression of a constitutively active form of PINK1 caused cell death in the presence of a pan-caspase inhibitor, irrespective of the mitochondrial membrane potential. PINK1-mediated cell death depended on the activities of PARKIN and proteasomes, but it was not affected by disruption of the genes required for autophagy. Furthermore, fluorescence and electron microscopic analyses revealed that mitochondria were still retained in the dead cells, indicating that PINK1-mediated cell death is not caused by mitochondrial loss. Our findings suggest that PINK1 and PARKIN play critical roles in selective cell death in which damaged mitochondria are retained, independent of mitochondrial autophagy. PMID:27302064
Decellularized extracellular matrices produced from immortal cell lines derived from different parts of the placenta support primary mesenchymal stem cell expansion

PubMed Central

Kusuma, Gina D.; Brennecke, Shaun P.; O’Connor, Andrea J.; Kalionis, Bill

2017-01-01

Mesenchymal stem/stromal cells (MSCs) exhibit undesired phenotypic changes during ex vivo expansion, limiting production of the large quantities of high quality primary MSCs needed for both basic research and cell therapies. Primary MSCs retain many desired MSC properties including proliferative capacity and differentiation potential when expanded on decellularized extracellular matrix (dECM) prepared from primary MSCs. However, the need to use low passage number primary MSCs (passage 3 or lower) to produce the dECM drastically limits the utility and impact of this technology. Here, we report that primary MSCs expanded on dECM prepared from high passage number (passage 25) human telomerase reverse transcriptase (hTERT) transduced immortal MSC cell lines also exhibit increased proliferation and osteogenic differentiation. Two hTERT-transduced placenta-derived MSC cell lines, CMSC29 and DMSC23 [derived from placental chorionic villi (CMSCs) and decidua basalis (DMSCs), respectively], were used to prepare dECM-coated substrates. These dECM substrates showed structural and biochemical differences. Primary DMSCs cultured on dECM-DMSC23 showed a three-fold increase in cell number after 14 days expansion in culture and increased osteogenic differentiation compared with controls. Primary CMSCs cultured on the dECM-DMSC23 exhibited a two-fold increase in cell number and increased osteogenic differentiation. We conclude that immortal MSC cell lines derived from different parts of the placenta produce dECM with varying abilities for supporting increased primary MSC expansion while maintaining important primary MSC properties. Additionally, this is the first demonstration of using high passage number cells to produce dECM that can promote primary MSC expansion, and this advancement greatly increases the feasibility and applicability of dECM-based technologies. PMID:28152107
Decellularized extracellular matrices produced from immortal cell lines derived from different parts of the placenta support primary mesenchymal stem cell expansion.

PubMed

Kusuma, Gina D; Brennecke, Shaun P; O'Connor, Andrea J; Kalionis, Bill; Heath, Daniel E

2017-01-01

Mesenchymal stem/stromal cells (MSCs) exhibit undesired phenotypic changes during ex vivo expansion, limiting production of the large quantities of high quality primary MSCs needed for both basic research and cell therapies. Primary MSCs retain many desired MSC properties including proliferative capacity and differentiation potential when expanded on decellularized extracellular matrix (dECM) prepared from primary MSCs. However, the need to use low passage number primary MSCs (passage 3 or lower) to produce the dECM drastically limits the utility and impact of this technology. Here, we report that primary MSCs expanded on dECM prepared from high passage number (passage 25) human telomerase reverse transcriptase (hTERT) transduced immortal MSC cell lines also exhibit increased proliferation and osteogenic differentiation. Two hTERT-transduced placenta-derived MSC cell lines, CMSC29 and DMSC23 [derived from placental chorionic villi (CMSCs) and decidua basalis (DMSCs), respectively], were used to prepare dECM-coated substrates. These dECM substrates showed structural and biochemical differences. Primary DMSCs cultured on dECM-DMSC23 showed a three-fold increase in cell number after 14 days expansion in culture and increased osteogenic differentiation compared with controls. Primary CMSCs cultured on the dECM-DMSC23 exhibited a two-fold increase in cell number and increased osteogenic differentiation. We conclude that immortal MSC cell lines derived from different parts of the placenta produce dECM with varying abilities for supporting increased primary MSC expansion while maintaining important primary MSC properties. Additionally, this is the first demonstration of using high passage number cells to produce dECM that can promote primary MSC expansion, and this advancement greatly increases the feasibility and applicability of dECM-based technologies.
Biocompatible and label-free separation of cancer cells from cell culture lines from white blood cells in ferrofluids.

PubMed

Zhao, Wujun; Cheng, Rui; Lim, So Hyun; Miller, Joshua R; Zhang, Weizhong; Tang, Wei; Xie, Jin; Mao, Leidong

2017-06-27

This paper reports a biocompatible and label-free cell separation method using ferrofluids that can separate a variety of low-concentration cancer cells from cell culture lines (∼100 cancer cells per mL) from undiluted white blood cells, with a throughput of 1.2 mL h -1 and an average separation efficiency of 82.2%. The separation is based on the size difference of the cancer cells and white blood cells, and is conducted in a custom-made biocompatible ferrofluid that retains not only excellent short-term viabilities but also normal proliferations of 7 commonly used cancer cell lines. A microfluidic device is designed and optimized specifically to shorten the time of live cells' exposure to ferrofluids from hours to seconds, by eliminating time-consuming off-chip sample preparation and extraction steps and integrating them on-chip to achieve a one-step process. As a proof-of-concept demonstration, a ferrofluid with 0.26% volume fraction was used in this microfluidic device to separate spiked cancer cells from cell lines at a concentration of ∼100 cells per mL from white blood cells with a throughput of 1.2 mL h -1 . The separation efficiencies were 80 ± 3%, 81 ± 5%, 82 ± 5%, 82 ± 4%, and 86 ± 6% for A549 lung cancer, H1299 lung cancer, MCF-7 breast cancer, MDA-MB-231 breast cancer, and PC-3 prostate cancer cell lines, respectively. The separated cancer cells' purity was between 25.3% and 28.8%. In addition, the separated cancer cells from this strategy showed an average short-term viability of 94.4 ± 1.3%, and these separated cells were cultured and demonstrated normal proliferation to confluence even after the separation process. Owing to its excellent biocompatibility and label-free operation and its ability to recover low concentrations of cancer cells from white blood cells, this method could lead to a promising tool for rare cell separation.
Establishment and characterization of a dairy goat mammary epithelial cell line with human telomerase (hT-MECs).

PubMed

Shi, Huaiping; Shi, Hengbo; Luo, Jun; Wang, Wei; Haile, Abiel B; Xu, Huifen; Li, Jun

2014-07-01

Although research on dairy goat mammary gland have referred extensively to molecular mechanisms, research on lines of dairy goat mammary epithelial cells (MECs) are still rare. This paper sought to establish an immortal MEC line by stable transfection of human telomerase. MECs from a lactating (45 days post-parturition) Xinong Saanen dairy goat were cultured purely and subsequently transfected with a plasmid carrying the sequence of human telomerase. Immortalized MECs by human telomerase (hT-MECs) exhibited a typical cobblestone morphology and activity and expression levels of telomerase resembled that of MCF-7 cells. hT-MECs on passage 42 grew vigorously and 'S' sigmoid curves of growth were observed. Moreover, hT-MECs maintained a normal chromosome modal number of 2n=60, keratin 8 and epithelial membrane antigen (EMA) were evidently expressed, and beta-casein protein was synthesized and secreted. Beta-casein expression was enhanced by prolactin (P<0.05). Lipid droplets were found in hT-MECs, and messenger RNA levels of PPARG, SREBP, FASN, ACC and SCD in hT-MECs (passage 40) were similar to MECs (passage 7). In conclusion, the obtained hT-MEC line retained a normal morphology, growth characteristics, cytogenetics and secretory characteristics as primary MECs. Hence, it can be a representative model cell line, for molecular and functional analysis, of dairy goat MECs for an extended period of time. © 2014 Japanese Society of Animal Science.
Autophagic Cell Death, Polyploidy and Senescence Induced in Breast Tumor Cells by the Substituted Pyrrole JG-03-14, a Novel Microtubule Poison

PubMed Central

Arthur, Christopher R.; Gupton, John T.; Kellogg, Glen E.; Yeudall, W. Andrew; Cabot, Myles C.; Newsham, Irene; Gewirtz, David A.

2007-01-01

JG-03-14, a substituted pyrrole that inhibits microtubule polymerization, was screened against MCF-7 (p53 wild type), MDA-MB 231 (p53 mutant), MCF-7/caspase 3 and MCF-7/ADR (multidrug resistant) breast tumor cell lines. Cell viability and growth inhibition were assessed by the crystal violet dye assay. Apoptosis was evaluated by the TUNEL assay, cell cycle distribution by flow cytometry, autophagy by acridine orange staining of vesicle formation, and senescence based on β-galactosidase staining and cell morphology. Our studies indicate that exposure to JG-03-14, at a concentration of 500 nM, induces time dependent cell death in the MCF-7 and MDA-MB 231 cell lines. In MCF-7 cells, a residual surviving cell population was found to be senescent; in contrast, there was no surviving senescent population in treated MDA-MB 231 cells. No proliferative recovery was detected over a period of 15 days post-treatment in either cell line. Both the TUNEL assay and FLOW cytometry indicated a relatively limited degree of apoptosis (< 10%) in response to drug treatment in MCF-7 cells with more extensive apoptosis (but < 20%) in MDA-MB231 cells; acidic vacuole formation indicative of autophagic cell death was relatively extensive in both MCF-7 and MDA-MB231 cells. In addition, JG-03-14 induced the formation of a large hyperdiploid cell population in MDA-MB231 cells. JG-03-14 also demonstrated pronounced anti-proliferative activity in MCF-7/caspase 3 cells and in the MCF-7/ADR cell line. The observation that JG-03-14 promotes autophagic cell death and also retains activity in tumor cells expressing the multidrug resistance pump indicates that novel microtubule poisons of the substituted pyrroles class may hold promise in the treatment of breast cancer. PMID:17692290
Viral microRNA effects on persistent infection of human lymphoid cells by polyomavirus SV40

PubMed Central

McNees, Adrienne L.; Harrigal, Lindsay J.; Kelly, Aoife; Minard, Charles G.; Wong, Connie

2018-01-01

Background Polyomaviruses, including simian virus 40 (SV40), display evidence of lymphotropic properties. This study analyzed the nature of SV40–human lymphocyte interactions in established cell lines and in primary lymphocytes. The effects of viral microRNA and the structure of the viral regulatory region on SV40 persistence were examined. Results SV40 DNA was maintained in infected B cell and myeloid cell lines during cell growth for at least 28 days. Limiting dilution analysis showed that low amounts of SV40 DNA (~2 copies per cell) were retained over time. Infected B cells remained viable and able to proliferate. Genome copies of the SV40 microRNA-null mutant persisted at higher levels than the DNA of wild-type viruses. Complex viral regulatory regions produced modestly higher DNA levels than simple regulatory regions. Viral large T-antigen protein was detected at low frequency and at low levels in infected B cells. Following infection of primary lymphocytes, SV40 DNA was detected in CD19+ B cells and CD14+ monocytes, but not in CD3+ T cells. Rescue attempts using either lysates of SV40-infected B lymphocytes, coculture of live cells, or infectious center assays all showed that replication-competent SV40 could be recovered on rare occasions. SV40 infections altered the expression of several B cell surface markers, with more pronounced changes following infections with the microRNA-null mutant. Conclusion These findings indicate that SV40 can establish persistent infections in human B lymphocytes. The cells retain low copy numbers of viral DNA; the infections are nonproductive and noncytolytic but can occasionally produce infectious virus. SV40 microRNA negatively regulates the degree of viral effects on B cells. Significance Lymphocytes may serve as viral reservoirs and may function to disseminate polyomaviruses to different tissues in a host. To our knowledge, this report is the first extensive analysis of viral microRNA effects on SV40 infection of human lymphocytes. PMID:29432481
Flavopiridol sensitivity of cancer cells isolated from ascites and pleural fluids.

PubMed

Richard, Christina; Matthews, Donald; Duivenvoorden, Wilhelmina; Yau, Jonathan; Wright, Paul S; Th'ng, John P H

2005-05-01

We examined the efficacy of flavopiridol, a cyclin-dependent kinase inhibitor that is undergoing clinical trials, on primary cancer cells isolated from the ascites or pleural fluids of patients with metastatic cancers. Metastasized cancer cells were isolated from the pleural fluids (n = 20) or ascites (n = 15) of patients, most of whom were refractory to chemotherapy. These primary cancer cells were used within 2 weeks of isolation without selecting for proliferative capacities. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide viability assay was used to characterize the response of these cancer cells to commonly used chemotherapeutic agents, and their response to flavopiridol was compared with rapidly dividing cultured cell lines. The primary cancer cells displayed phenotypes that were different from established cell lines; they had very low replication rates, dividing every 1 to 2 weeks, and underwent replicative senescence within five passages. These primary tumor cells retained their resistance to chemotherapeutic drugs exhibited by the respective patients but did not show cross-resistance to other agents. However, these cancer cells showed sensitivity to flavopiridol with an average LD50 of 50 nmol/L (range, 21.5-69 nmol/L), similar to the LD50 in established cell lines. Because senescent cells also showed similar sensitivity to flavopiridol, it suggests that the mechanism of action is not dependent on the activity of cyclin-dependent kinases that regulate the progression of the cell cycle. Using cancer cells isolated from the ascites or pleural fluids, this study shows the potential of flavopiridol against cancer cells that have developed resistance to conventional chemotherapeutic agents.
Confocal Raman microscopy of pathologic cells in cerebrospinal fluid

NASA Astrophysics Data System (ADS)

Gonchukov, S. A.; Lonkina, T. V.; Minaeva, S. A.; Sundukov, A. V.; Migmanov, T. E.; Lademann, J.; Darvin, M. E.; Bagratashvili, V. N.

2014-01-01

In this work, the spatial localization of leucocytes, bacteria, and erythrocytes in the crystal pattern of a dried droplet of cerebrospinal fluid (CSF) is established. Characteristic lines are detected and identified in the Raman spectrum of the CSF that point to the presence of pathologic cells therein and can be used in a timely way to diagnose meningitis, the spectroscopic sample preparation procedure being simple enough. A dry CSF sample retains its characteristic spectral features for no less than three days, which is important for its safe keeping and transportation, and also for the computer processing of its spectra.
The mouse tumor cell lines EL4 and RMA display mosaic expression of NK-related and certain other surface molecules and appear to have a common origin.

PubMed

Gays, F; Unnikrishnan, M; Shrestha, S; Fraser, K P; Brown, A R; Tristram, C M; Chrzanowska-Lightowlers, Z M; Brooks, C G

2000-05-15

As a potential means for facilitating studies of NK cell-related molecules, we examined the expression of these molecules on a range of mouse tumor cell lines. Of the lines we initially examined, only EL4 and RMA expressed such molecules, both lines expressing several members of the Ly49 and NKRP1 families. Unexpectedly, several of the NK-related molecules, together with certain other molecules including CD2, CD3, CD4, CD32, and CD44, were often expressed in a mosaic manner, even on freshly derived clones, indicating frequent switching in expression. In each case examined, switching was controlled at the mRNA level, with expression of CD3zeta determining expression of the entire CD3-TCR complex. Each of the variable molecules was expressed independently, with the exception that CD3 was restricted to cells that also expressed CD2. Treatment with drugs that affect DNA methylation and histone acetylation could augment the expression of at least some of the variable molecules. The striking phenotypic similarity between EL4 and RMA led us to examine the state of their TCRbeta genes. Both lines had identical rearrangements on both chromosomes, indicating that RMA is in fact a subline of EL4. Overall, these findings suggest that EL4 is an NK-T cell tumor that may have retained a genetic mechanism that permits the variable expression of a restricted group of molecules involved in recognition and signaling.
Establishment of a Conditionally Immortalized Wilms Tumor Cell Line with a Homozygous WT1 Deletion within a Heterozygous 11p13 Deletion and UPD Limited to 11p15.

PubMed

Brandt, Artur; Löhers, Katharina; Beier, Manfred; Leube, Barbara; de Torres, Carmen; Mora, Jaume; Arora, Parineeta; Jat, Parmjit S; Royer-Pokora, Brigitte

2016-01-01

We describe a stromal predominant Wilms tumor with focal anaplasia and a complex, tumor specific chromosome 11 aberration: a homozygous deletion of the entire WT1 gene within a heterozygous 11p13 deletion and an additional region of uniparental disomy (UPD) limited to 11p15.5-p15.2 including the IGF2 gene. The tumor carried a heterozygous p.T41A mutation in CTNNB1. Cells established from the tumor carried the same chromosome 11 aberration, but a different, homozygous p.S45Δ CTNNB1 mutation. Uniparental disomy (UPD) 3p21.3pter lead to the homozygous CTNNB1 mutation. The tumor cell line was immortalized using the catalytic subunit of human telomerase (hTERT) in conjunction with a novel thermolabile mutant (U19dl89-97tsA58) of SV40 large T antigen (LT). This cell line is cytogenetically stable and can be grown indefinitely representing a valuable tool to study the effect of a complete lack of WT1 in tumor cells. The origin/fate of Wilms tumors with WT1 mutations is currently poorly defined. Here we studied the expression of several genes expressed in early kidney development, e.g. FOXD1, PAX3, SIX1, OSR1, OSR2 and MEIS1 and show that these are expressed at similar levels in the parental and the immortalized Wilms10 cells. In addition the limited potential for muscle/ osteogenic/ adipogenic differentiation similar to all other WT1 mutant cell lines is also observed in the Wilms10 tumor cell line and this is retained in the immortalized cells. In summary these Wilms10 cells are a valuable model system for functional studies of WT1 mutant cells.
Establishment of a Conditionally Immortalized Wilms Tumor Cell Line with a Homozygous WT1 Deletion within a Heterozygous 11p13 Deletion and UPD Limited to 11p15

PubMed Central

Brandt, Artur; Löhers, Katharina; Beier, Manfred; Leube, Barbara; de Torres, Carmen; Mora, Jaume; Arora, Parineeta; Jat, Parmjit S.; Royer-Pokora, Brigitte

2016-01-01

We describe a stromal predominant Wilms tumor with focal anaplasia and a complex, tumor specific chromosome 11 aberration: a homozygous deletion of the entire WT1 gene within a heterozygous 11p13 deletion and an additional region of uniparental disomy (UPD) limited to 11p15.5-p15.2 including the IGF2 gene. The tumor carried a heterozygous p.T41A mutation in CTNNB1. Cells established from the tumor carried the same chromosome 11 aberration, but a different, homozygous p.S45Δ CTNNB1 mutation. Uniparental disomy (UPD) 3p21.3pter lead to the homozygous CTNNB1 mutation. The tumor cell line was immortalized using the catalytic subunit of human telomerase (hTERT) in conjunction with a novel thermolabile mutant (U19dl89-97tsA58) of SV40 large T antigen (LT). This cell line is cytogenetically stable and can be grown indefinitely representing a valuable tool to study the effect of a complete lack of WT1 in tumor cells. The origin/fate of Wilms tumors with WT1 mutations is currently poorly defined. Here we studied the expression of several genes expressed in early kidney development, e.g. FOXD1, PAX3, SIX1, OSR1, OSR2 and MEIS1 and show that these are expressed at similar levels in the parental and the immortalized Wilms10 cells. In addition the limited potential for muscle/ osteogenic/ adipogenic differentiation similar to all other WT1 mutant cell lines is also observed in the Wilms10 tumor cell line and this is retained in the immortalized cells. In summary these Wilms10 cells are a valuable model system for functional studies of WT1 mutant cells. PMID:27213811
Development of a New Conditionally Immortalized Human Liver Sinusoidal Endothelial Cells.

PubMed

Zhu, Meiyan; Koibuchi, Akira; Ide, Hideyuki; Morio, Hanae; Shibuya, Minaka; Kamiichi, Atsuko; Tsubota, Akihito; Anzai, Naohiko; Akita, Hidetaka; Chiba, Kan; Furihata, Tomomi

2018-01-01

Liver sinusoidal endothelial cells (LSECs), which are specialized endothelial cells that line liver sinusoids, have been reported to participate in a variety of liver functions, such as blood macromolecule clearance and factor VIII production. In addition, LSECs play crucial roles in liver regeneration following acute liver injury, as well as the development and progression of liver diseases or drug-induced hepatotoxicity. However, the molecular mechanisms underlying their roles remain mostly unknown. Therefore, in order to contribute to the clarification of those mechanisms, herein we report on the development of a new immortalized human LSEC (HLSEC) line. To produce this cell line, two immortalized genes were introduced into the primary HLSECs, which eventually resulted in the establishment of the HLSEC/conditionally immortalized, clone-J (HLSEC/ciJ). Consistent with the two-immortalized gene expression, HLSEC/ciJ showed excellent proliferation activity. Additionally, the results of gene expression analyses showed that several LSEC (as well as pan-endothelial) marker mRNAs and proteins were clearly expressed in HLSEC/ciJ. Furthermore, we found that adherence junction proteins were localized at the cell border in the HLSEC/ciJ monolayer, and that the cells exhibited a tube-like structure formation property. Taken together, the results obtained thus far indicate that we have successfully immortalized HLSECs, resulting in creation of HLSEC/ciJ, a cell line that possesses infinite proliferation ability while retaining possession of at least some HLSEC features. We believe that the HLSEC/ciJ have the potential to provide a valuable and unlimited alternative source of HLSECs for use in liver/LSEC physiology/pathophysiology, pharmacology, and toxicology studies.
Intracellular localization of pregnane X receptor in HepG2 cells cultured by the hanging drop method.

PubMed

Yokobori, Kosuke; Kobayashi, Kaoru; Azuma, Ikuko; Akita, Hidetaka; Chiba, Kan

2017-10-01

Pregnane X receptor (PXR) is localized in the cytoplasm of liver cells, whereas it is localized in the nucleus of monolayer-cultured HepG2 cells. Since cultured cells are affected by the microenvironment in which they are grown, we studied the effect of three-dimensional (3D) culture on the localization of PXR in HepG2 cells using the hanging drop method. The results showed that PXR was retained in the cytoplasm of HepG2 cells and other human hepatocarcinoma cell lines (FLC5, FLC7 and Huh7) when they were cultured by the hanging drop method. Treatment with rifampicin, a ligand of PXR, translocated PXR from the cytoplasm to nucleus and increased expression levels of CYP3A4 mRNA in HepG2 cells cultured by the hanging drop method. These findings suggest that 3D culture is a key factor determining the intracellular localization of PXR in human hepatocarcinoma cells and that PXR that becomes retained in the cytoplasm of HepG2 cells with 3D culture has functions of nuclear translocation and regulation of target genes in response to human PXR ligands. Three-dimensionally cultured hepatocarcinoma cells would be a useful tool to evaluate induction potency of drug candidates and also to study mechanisms of nuclear translocation of PXR by human PXR ligands. Copyright © 2017 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.
Simultaneous suppression of TGF-β and ERK signaling contributes to the highly efficient and reproducible generation of mouse embryonic stem cells from previously considered refractory and non-permissive strains.

PubMed

Hassani, Seyedeh-Nafiseh; Totonchi, Mehdi; Farrokhi, Ali; Taei, Adeleh; Larijani, Mehran Rezaei; Gourabi, Hamid; Baharvand, Hossein

2012-06-01

Mouse embryonic stem cells (ESCs) are pluripotent stem cell lines derived from pre-implantation embryos. The efficiency of mESC generation is affected by genetic variation in mice; that is, some mouse strains are refractory or non-permissive to ESC establishment. Developing an efficient method to derive mESCs from strains of various genetic backgrounds should be valuable for establishment of ESCs in various mammalian species. In the present study, we identified dual inhibition of TGF-β and ERK1/2, by SB431542 and PD0325901, respectively led to the highly efficient and reproducible generation of mESC lines from NMRI, C57BL/6, BALB/c, DBA/2, and FVB/N strains, which previously considered refractory or non-permissive for ESC establishment. These mESCs expressed pluripotency markers and retained the capacity to differentiate into derivatives of all three germ layers. The evaluated lines exhibited high rates of chimerism when reintroduced into blastocysts. To our knowledge, this is the first report of efficient (100%) mESC lines generation from different genetic backgrounds. The application of these two inhibitors will not only solve the problems of mESC derivation but also clarifies new signaling pathways in pluripotent mESCs.
The Cables Gene on Chromosome 18q Is Silenced by Promoter Hypermethylation and Allelic Loss in Human Colorectal Cancer

PubMed Central

Park, Do Youn; Sakamoto, Hideo; Kirley, Sandra D.; Ogino, Shuji; Kawasaki, Takako; Kwon, Eunjeong; Mino-Kenudson, Mari; Lauwers, Gregory Y.; Chung, Daniel C.; Rueda, Bo R.; Zukerberg, Lawrence R.

2007-01-01

Cables is a cyclin-dependent kinase-binding nuclear protein that maps to chromosome 18q11-12. Here, we assessed Cables expression in 160 colorectal cancers (CRCs), its role in colon cancer cell growth, and the potential mechanisms of Cables inactivation. Expression levels, promoter methylation, and mutational status of Cables were investigated in colon cancer cell lines and primary colon tumors. Chromosome 18q loss of heterozygosity (LOH) was evaluated with multiple polymorphic markers. Cables inhibited cellular proliferation and colony formation in colon cancer cell lines. Cables expression was reduced in 65% of primary CRCs. No mutations were detected in 10 exons of Cables in 20 primary colon tumors. Cables promoter was methylated in cell lines with decreased Cables expression and vice versa. 5-Aza-2′-deoxycytidine resulted in increased Cables expression in methylated cell lines. There was a significant correlation between promoter methylation and Cables gene expression in primary colon tumors. Sixty-five percent of primary colon tumors demonstrated chromosome 18q LOH. LOH involving the Cables region was observed in 35% of cases, including those in which more distal portions of chromosome 18q were retained, and Cables expression was decreased in all such cases. Loss of Cables expression in 65% of CRCs suggests that it is a common event in colonic carcinogenesis, with promoter methylation and LOH appearing to be important mechanisms of Cables gene inactivation. PMID:17982127
A simple non-perturbing cell migration assay insensitive to proliferation effects

PubMed Central

Glenn, Honor L.; Messner, Jacob; Meldrum, Deirdre R.

2016-01-01

Migration is a fundamental cellular behavior that plays an indispensable role in development and homeostasis, but can also contribute to pathology such as cancer metastasis. Due to its relevance to many aspects of human health, the ability to accurately measure cell migration is of broad interest, and numerous approaches have been developed. One of the most commonly employed approaches, because of its simplicity and throughput, is the exclusion zone assay in which cells are allowed to migrate into an initially cell-free region. A major drawback of this assay is that it relies on simply counting cells in the exclusion zone and therefore cannot distinguish the effects of proliferation from migration. We report here a simple modification to the exclusion zone migration assay that exclusively measures cell migration and is not affected by proliferation. This approach makes use of a lineage-tracing vital stain that is retained through cell generations and effectively reads out migration relative to the original, parental cell population. This modification is simple, robust, non-perturbing, and inexpensive. We validate the method in a panel of cell lines under conditions that inhibit or promote migration and demonstrate its use in normal and cancer cell lines as well as primary cells. PMID:27535324
Extensive and systematic rewiring of histone post-translational modifications in cancer model systems.

PubMed

Noberini, Roberta; Osti, Daniela; Miccolo, Claudia; Richichi, Cristina; Lupia, Michela; Corleone, Giacomo; Hong, Sung-Pil; Colombo, Piergiuseppe; Pollo, Bianca; Fornasari, Lorenzo; Pruneri, Giancarlo; Magnani, Luca; Cavallaro, Ugo; Chiocca, Susanna; Minucci, Saverio; Pelicci, Giuliana; Bonaldi, Tiziana

2018-05-04

Histone post-translational modifications (PTMs) generate a complex combinatorial code that regulates gene expression and nuclear functions, and whose deregulation has been documented in different types of cancers. Therefore, the availability of relevant culture models that can be manipulated and that retain the epigenetic features of the tissue of origin is absolutely crucial for studying the epigenetic mechanisms underlying cancer and testing epigenetic drugs. In this study, we took advantage of quantitative mass spectrometry to comprehensively profile histone PTMs in patient tumor tissues, primary cultures and cell lines from three representative tumor models, breast cancer, glioblastoma and ovarian cancer, revealing an extensive and systematic rewiring of histone marks in cell culture conditions, which includes a decrease of H3K27me2/me3, H3K79me1/me2 and H3K9ac/K14ac, and an increase of H3K36me1/me2. While some changes occur in short-term primary cultures, most of them are instead time-dependent and appear only in long-term cultures. Remarkably, such changes mostly revert in cell line- and primary cell-derived in vivo xenograft models. Taken together, these results support the use of xenografts as the most representative models of in vivo epigenetic processes, suggesting caution when using cultured cells, in particular cell lines and long-term primary cultures, for epigenetic investigations.

Extensive and systematic rewiring of histone post-translational modifications in cancer model systems

PubMed Central

Noberini, Roberta; Osti, Daniela; Miccolo, Claudia; Richichi, Cristina; Lupia, Michela; Corleone, Giacomo; Hong, Sung-Pil; Colombo, Piergiuseppe; Pollo, Bianca; Fornasari, Lorenzo; Pruneri, Giancarlo; Magnani, Luca; Cavallaro, Ugo; Chiocca, Susanna; Minucci, Saverio; Pelicci, Giuliana; Bonaldi, Tiziana

2018-01-01

Abstract Histone post-translational modifications (PTMs) generate a complex combinatorial code that regulates gene expression and nuclear functions, and whose deregulation has been documented in different types of cancers. Therefore, the availability of relevant culture models that can be manipulated and that retain the epigenetic features of the tissue of origin is absolutely crucial for studying the epigenetic mechanisms underlying cancer and testing epigenetic drugs. In this study, we took advantage of quantitative mass spectrometry to comprehensively profile histone PTMs in patient tumor tissues, primary cultures and cell lines from three representative tumor models, breast cancer, glioblastoma and ovarian cancer, revealing an extensive and systematic rewiring of histone marks in cell culture conditions, which includes a decrease of H3K27me2/me3, H3K79me1/me2 and H3K9ac/K14ac, and an increase of H3K36me1/me2. While some changes occur in short-term primary cultures, most of them are instead time-dependent and appear only in long-term cultures. Remarkably, such changes mostly revert in cell line- and primary cell-derived in vivo xenograft models. Taken together, these results support the use of xenografts as the most representative models of in vivo epigenetic processes, suggesting caution when using cultured cells, in particular cell lines and long-term primary cultures, for epigenetic investigations. PMID:29618087
The hypothalamic satiety peptide CART is expressed in anorectic and non-anorectic pancreatic islet tumors and in the normal islet of Langerhans.

PubMed

Jensen, P B; Kristensen, P; Clausen, J T; Judge, M E; Hastrup, S; Thim, L; Wulff, B S; Foged, C; Jensen, J; Holst, J J; Madsen, O D

1999-03-26

The hypothalamic satiety peptide CART (cocaine and amphetamine regulated transcript) is expressed at high levels in anorectic rat glucagonomas but not in hypoglycemic insulinomas. However, a non-anorectic metastasis derived from the glucagonoma retained high CART expression levels and produced circulating CART levels comparable to that of the anorectic tumors. Moreover, distinct glucagonoma lines derived by stable HES-1 transfection of the insulinoma caused severe anorexia but retained low circulating levels of CART comparable to that of insulinoma bearing or control rats. Islet tumor associated anorexia and circulating CART levels are thus not correlated, and in line with this peripheral administration of CART (5-50 mg/kg) produced no effect on feeding behavior. In the rat two alternatively spliced forms of CART mRNA exist and quantitative PCR revealed expression of both forms in the hypothalamus, in the different islet tumors, and in the islets of Langerhans. Immunocytochemistry as well as in situ hybridization localized CART expression to the somatostatin producing islet D cell. A potential endocrine/paracrine role of islet CART remains to be clarified.
Restricting lignin and enhancing sugar deposition in secondary cell walls enhances monomeric sugar release after low temperature ionic liquid pretreatment

DOE PAGES

Scullin, Chessa; Cruz, Alejandro G.; Chuang, Yi -De; ...

2015-07-04

Lignocellulosic biomass has the potential to be a major source of renewable sugar for biofuel production. Before enzymatic hydrolysis, biomass must first undergo a pretreatment step in order to be more susceptible to saccharification and generate high yields of fermentable sugars. Lignin, a complex, interlinked, phenolic polymer, associates with secondary cell wall polysaccharides, rendering them less accessible to enzymatic hydrolysis. Herein, we describe the analysis of engineered Arabidopsis lines where lignin biosynthesis was repressed in fiber tissues but retained in the vessels, and polysaccharide deposition was enhanced in fiber cells with little to no apparent negative impact on growth phenotype.
Restricting lignin and enhancing sugar deposition in secondary cell walls enhances monomeric sugar release after low temperature ionic liquid pretreatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scullin, Chessa; Cruz, Alejandro G.; Chuang, Yi -De

Lignocellulosic biomass has the potential to be a major source of renewable sugar for biofuel production. Before enzymatic hydrolysis, biomass must first undergo a pretreatment step in order to be more susceptible to saccharification and generate high yields of fermentable sugars. Lignin, a complex, interlinked, phenolic polymer, associates with secondary cell wall polysaccharides, rendering them less accessible to enzymatic hydrolysis. Herein, we describe the analysis of engineered Arabidopsis lines where lignin biosynthesis was repressed in fiber tissues but retained in the vessels, and polysaccharide deposition was enhanced in fiber cells with little to no apparent negative impact on growth phenotype.
Vitamin E and mast cells.

PubMed

Zingg, Jean-Marc

2007-01-01

Mast cells play an important role in the immune system by interacting with B and T cells and by releasing several mediators involved in activating other cells. Hyperreactivity of mast cells and their uncontrolled accumulation in tissues lead to increased release of inflammatory mediators contributing to the pathogenesis of several diseases such as rheumatoid arthritis, atherosclerosis, multiple sclerosis, and allergic disorders such as asthma and allergic rhinitis. Interference with mast cell proliferation, survival, degranulation, and migration by synthetic or natural compounds may represent a preventive strategy for the management of these diseases. Natural vitamin E covers a group of eight analogues-the alpha-, beta-, gamma-, and delta-tocopherols and the alpha-, beta-, gamma-, and delta-tocotrienols, but only alpha-tocopherol is efficiently retained by the liver and distributed to peripheral tissues. Mast cells preferentially locate in the proximity of tissues that interface with the external environment (the epithelial surface of the skin, the gastrointestinal mucosa, and the respiratory system), what may render them accessible to treatments with inefficiently retained natural vitamin E analogues and synthetic derivatives. In addition to scavenging free radicals, the natural vitamin E analogues differently modulate signal transduction and gene expression in several cell lines; in mast cells, protein kinase C, protein phosphatase 2A, and protein kinase B are affected by vitamin E, leading to the modulation of proliferation, apoptosis, secretion, and migration. In this chapter, the possibility that vitamin E can prevent diseases with mast cells involvement by modulating signal transduction and gene expression is evaluated.
BAG-1 enhances cell-cell adhesion, reduces proliferation and induces chaperone-independent suppression of hepatocyte growth factor-induced epidermal keratinocyte migration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hinitt, C.A.M.; Wood, J.; Lee, S.S.

2010-08-01

Cell motility is important in maintaining tissue homeostasis, facilitating epithelial wound repair and in tumour formation and progression. The aim of this study was to determine whether BAG-1 isoforms regulate epidermal cell migration in in vitro models of wound healing. In the human epidermal cell line HaCaT, endogenous BAG-1 is primarily nuclear and increases with confluence. Both transient and stable p36-Bag-1 overexpression resulted in increased cellular cohesion. Stable transfection of either of the three human BAG-1 isoforms p36-Bag-1 (BAG-1S), p46-Bag-1 (BAG-1M) and p50-Bag-1 (BAG-1L) inhibited growth and wound closure in serum-containing medium. However, in response to hepatocyte growth factor (HGF)more » in serum-free medium, BAG-1S/M reduced communal motility and colony scattering, but BAG-1L did not. In the presence of HGF, p36-Bag-1 transfectants retained proliferative response to HGF with no change in ERK1/2 activation. However, the cells retained E-cadherin localisation at cell-cell junctions and exhibited pronounced cortical actin. Point mutations in the BAG domain showed that BAG-1 inhibition of motility is independent of its function as a chaperone regulator. These findings are the first to suggest that BAG-1 plays a role in regulating cell-cell adhesion and suggest an important function in epidermal cohesion.« less
Albumin/asparaginase capsules prepared by ultrasound to retain ammonia.

PubMed

Tinoco, Ana; Ribeiro, Artur; Oliveira, César; Parpot, Pier; Gomes, Andreia; Cavaco-Paulo, Artur

2016-11-01

Asparaginase reduces the levels of asparagine in blood, which is an essential amino acid for the proliferation of lymphoblastic malign cells. Asparaginase converts asparagine into aspartic acid and ammonia. The accumulation of ammonia in the bloodstream leads to hyperammonemia, described as one of the most significant side effects of asparaginase therapy. Therefore, there is a need for asparaginase formulations with the potential to reduce hyperammonemia. We incorporated 2 % of therapeutic enzyme in albumin-based capsules. The presence of asparaginase in the interface of bovine serum albumin (BSA) capsules showed the ability to hydrolyze the asparagine and retain the forming ammonia at the surface of the capsules. The incorporation of Poloxamer 407 in the capsule formulation further increased the ratio aspartic acid/ammonia from 1.92 to 2.46 (and 1.10 from the free enzyme), decreasing the levels of free ammonia. This capacity to retain ammonia can be due to electrostatic interactions and retention of ammonia at the surface of the capsules. The developed BSA/asparaginase capsules did not cause significant cytotoxic effect on mouse leukemic macrophage cell line RAW 264.7. The new BSA/asparaginase capsules could potentially be used in the treatment of acute lymphoblastic leukemia preventing hyperammonemia associated with acute lymphoblastic leukemia (ALL) treatment with asparaginase.
Pediatric brain tumor cancer stem cells: cell cycle dynamics, DNA repair, and etoposide extrusion

PubMed Central

Hussein, Deema; Punjaruk, Wiyada; Storer, Lisa C.D.; Shaw, Lucy; Ottoman, Ramadan; Peet, Andrew; Miller, Suzanne; Bandopadhyay, Gagori; Heath, Rachel; Kumari, Rajendra; Bowman, Karen J.; Braker, Paul; Rahman, Ruman; Jones, George D.D.; Watson, Susan; Lowe, James; Kerr, Ian D.; Grundy, Richard G.; Coyle, Beth

2011-01-01

Reliable model systems are needed to elucidate the role cancer stem cells (CSCs) play in pediatric brain tumor drug resistance. The majority of studies to date have focused on clinically distinct adult tumors and restricted tumor types. Here, the CSC component of 7 newly established primary pediatric cell lines (2 ependymomas, 2 medulloblastomas, 2 gliomas, and a CNS primitive neuroectodermal tumor) was thoroughly characterized. Comparison of DNA copy number with the original corresponding tumor demonstrated that genomic changes present in the original tumor, typical of that particular tumor type, were retained in culture. In each case, the CSC component was approximately 3–4-fold enriched in neurosphere culture compared with monolayer culture, and a higher capacity for multilineage differentiation was observed for neurosphere-derived cells. DNA content profiles of neurosphere-derived cells expressing the CSC marker nestin demonstrated the presence of cells in all phases of the cell cycle, indicating that not all CSCs are quiescent. Furthermore, neurosphere-derived cells demonstrated an increased resistance to etoposide compared with monolayer-derived cells, having lower initial DNA damage, potentially due to a combination of increased drug extrusion by ATP-binding cassette multidrug transporters and enhanced rates of DNA repair. Finally, orthotopic xenograft models reflecting the tumor of origin were established from these cell lines. In summary, these cell lines and the approach taken provide a robust model system that can be used to develop our understanding of the biology of CSCs in pediatric brain tumors and other cancer types and to preclinically test therapeutic agents. PMID:20978004
Pediatric brain tumor cancer stem cells: cell cycle dynamics, DNA repair, and etoposide extrusion.

PubMed

Hussein, Deema; Punjaruk, Wiyada; Storer, Lisa C D; Shaw, Lucy; Othman, Ramadhan; Ottoman, Ramadan; Peet, Andrew; Miller, Suzanne; Bandopadhyay, Gagori; Heath, Rachel; Kumari, Rajendra; Bowman, Karen J; Braker, Paul; Rahman, Ruman; Jones, George D D; Watson, Susan; Lowe, James; Kerr, Ian D; Grundy, Richard G; Coyle, Beth

2011-01-01

Reliable model systems are needed to elucidate the role cancer stem cells (CSCs) play in pediatric brain tumor drug resistance. The majority of studies to date have focused on clinically distinct adult tumors and restricted tumor types. Here, the CSC component of 7 newly established primary pediatric cell lines (2 ependymomas, 2 medulloblastomas, 2 gliomas, and a CNS primitive neuroectodermal tumor) was thoroughly characterized. Comparison of DNA copy number with the original corresponding tumor demonstrated that genomic changes present in the original tumor, typical of that particular tumor type, were retained in culture. In each case, the CSC component was approximately 3-4-fold enriched in neurosphere culture compared with monolayer culture, and a higher capacity for multilineage differentiation was observed for neurosphere-derived cells. DNA content profiles of neurosphere-derived cells expressing the CSC marker nestin demonstrated the presence of cells in all phases of the cell cycle, indicating that not all CSCs are quiescent. Furthermore, neurosphere-derived cells demonstrated an increased resistance to etoposide compared with monolayer-derived cells, having lower initial DNA damage, potentially due to a combination of increased drug extrusion by ATP-binding cassette multidrug transporters and enhanced rates of DNA repair. Finally, orthotopic xenograft models reflecting the tumor of origin were established from these cell lines. In summary, these cell lines and the approach taken provide a robust model system that can be used to develop our understanding of the biology of CSCs in pediatric brain tumors and other cancer types and to preclinically test therapeutic agents.
Microtubule-stabilizing properties of the avocado-derived toxins (+)-(R)-persin and (+)-(R)-tetrahydropersin in cancer cells and activity of related synthetic analogs.

PubMed

Field, Jessica J; Kanakkanthara, Arun; Brooke, Darby G; Sinha, Saptarshi; Pillai, Sushila D; Denny, William A; Butt, Alison J; Miller, John H

2016-06-01

The avocado toxin (+)-R-persin (persin) is active at low micromolar concentrations against breast cancer cells and synergizes with the estrogen receptor modulator 4-hydroxytamoxifen. Previous studies in the estrogen receptor-positive breast cancer cell line MCF-7 indicate that persin acts as a microtubule-stabilizing agent. In the present study, we further characterize the properties of persin and several new synthetic analogues in human ovarian cancer cells. Persin and tetrahydropersin cause G2M cell cycle arrest and increase intracellular microtubule polymerization. One analog (4-nitrophenyl)-deshydroxypersin prevents cell proliferation and blocks cells in G1 of the cell cycle rather than G2M, suggesting an additional mode of action of these compounds independent of microtubules. Persin can synergize with other microtubule-stabilizing agents, and is active against cancer cells that overexpress the P-glycoprotein drug efflux pump. Evidence from Flutax-1 competition experiments suggests that while the persin binding site on β-tubulin overlaps the classical taxoid site where paclitaxel and epothilone bind, persin retains activity in cell lines with single amino acid mutations that affect these other taxoid site ligands. This implies the existence of a unique binding location for persin at the taxoid site.
Hepa1-6-FLuc cell line with the stable expression of firefly luciferase retains its primary properties with promising bioluminescence imaging ability.

PubMed

Li, Yasha; Liu, Mengnan; Cui, Jiejie; Yang, Ke; Zhao, Li; Gong, Mengjia; Wang, Yi; He, Yun; He, Tongchuan; Bi, Yang

2018-05-01

Reliable animal models are required for the in vivo study of the molecular mechanisms and effects of chemotherapeutic drugs in hepatocarcinoma. In vivo tracing techniques based on firefly luciferase (FLuc) may optimize the non-invasive monitoring of experimental animals. The present study established a murine Hepa1-6-FLuc cell line that stably expressed a retrovirus-delivered FLuc protein gene. The cell morphology, proliferation, migration and invasion ability of Hepa1-6-FLuc cells were the same as that of the Hepa1-6 cells, and thus is suitable to replace Hepa1-6 cells in the construction of hepatocarcinoma animal models. No differences in subcutaneous tumor mass and its pathomorphology from implanted Hepa1-6-FLuc cells were observed compared with Hepa1-6 control tumors. Bioluminescence imaging indicated that the Luc signal of the Hepa1-6-FLuc cells was consistently strengthened with increases in tumor mass; however, the Luc signal of Hepa1-6-AdFLuc became weaker and eventually disappeared during tumor development. Therefore, compared with the transient expression by adenovirus, stable expression of the FLuc gene in Hepa1-6 cells may better reflect cell proliferation and survival in vivo , and provide a reliable source for the establishment of hepatocarcinoma models.
Wnt activation of immortalized brain endothelial cells as a tool for generating a standardized model of the blood brain barrier in vitro.

PubMed

Paolinelli, Roberta; Corada, Monica; Ferrarini, Luca; Devraj, Kavi; Artus, Cédric; Czupalla, Cathrin J; Rudini, Noemi; Maddaluno, Luigi; Papa, Eleanna; Engelhardt, Britta; Couraud, Pierre Olivier; Liebner, Stefan; Dejana, Elisabetta

2013-01-01

Reproducing the characteristics and the functional responses of the blood-brain barrier (BBB) in vitro represents an important task for the research community, and would be a critical biotechnological breakthrough. Pharmaceutical and biotechnology industries provide strong demand for inexpensive and easy-to-handle in vitro BBB models to screen novel drug candidates. Recently, it was shown that canonical Wnt signaling is responsible for the induction of the BBB properties in the neonatal brain microvasculature in vivo. In the present study, following on from earlier observations, we have developed a novel model of the BBB in vitro that may be suitable for large scale screening assays. This model is based on immortalized endothelial cell lines derived from murine and human brain, with no need for co-culture with astrocytes. To maintain the BBB endothelial cell properties, the cell lines are cultured in the presence of Wnt3a or drugs that stabilize β-catenin, or they are infected with a transcriptionally active form of β-catenin. Upon these treatments, the cell lines maintain expression of BBB-specific markers, which results in elevated transendothelial electrical resistance and reduced cell permeability. Importantly, these properties are retained for several passages in culture, and they can be reproduced and maintained in different laboratories over time. We conclude that the brain-derived endothelial cell lines that we have investigated gain their specialized characteristics upon activation of the canonical Wnt pathway. This model may be thus suitable to test the BBB permeability to chemicals or large molecular weight proteins, transmigration of inflammatory cells, treatments with cytokines, and genetic manipulation.
Fas/CD95 prevents autoimmunity independently of lipid raft localization and efficient apoptosis induction

PubMed Central

Cruz, Anthony C.; Ramaswamy, Madhu; Ouyang, Claudia; Klebanoff, Christopher A.; Sengupta, Prabuddha; Yamamoto, Tori N.; Meylan, Françoise; Thomas, Stacy K.; Richoz, Nathan; Eil, Robert; Price, Susan; Casellas, Rafael; Rao, V. Koneti; Lippincott-Schwartz, Jennifer; Restifo, Nicholas P.; Siegel, Richard M.

2016-01-01

Mutations affecting the apoptosis-inducing function of the Fas/CD95 TNF-family receptor result in autoimmune and lymphoproliferative disease. However, Fas can also costimulate T-cell activation and promote tumour cell growth and metastasis. Palmitoylation at a membrane proximal cysteine residue enables Fas to localize to lipid raft microdomains and induce apoptosis in cell lines. Here, we show that a palmitoylation-defective Fas C194V mutant is defective in inducing apoptosis in primary mouse T cells, B cells and dendritic cells, while retaining the ability to enhance naive T-cell differentiation. Despite inability to efficiently induce cell death, the Fas C194V receptor prevents the lymphoaccumulation and autoimmunity that develops in Fas-deficient mice. These findings indicate that induction of apoptosis through Fas is dependent on receptor palmitoylation in primary immune cells, and Fas may prevent autoimmunity by mechanisms other than inducing apoptosis. PMID:28008916
MYCN amplification confers enhanced folate dependence and methotrexate sensitivity in neuroblastoma

PubMed Central

Lau, Diana T.; Flemming, Claudia L.; Gherardi, Samuele; Perini, Giovanni; Oberthuer, André; Fischer, Matthias; Juraeva, Dilafruz; Brors, Benedikt; Xue, Chengyuan; Norris, Murray D.; Marshall, Glenn M.; Haber, Michelle

2015-01-01

MYCN amplification occurs in 20% of neuroblastomas and is strongly related to poor clinical outcome. We have identified folate-mediated one-carbon metabolism as highly upregulated in neuroblastoma tumors with MYCN amplification and have validated this finding experimentally by showing that MYCN amplified neuroblastoma cell lines have a higher requirement for folate and are significantly more sensitive to the antifolate methotrexate than cell lines without MYCN amplification. We have demonstrated that methotrexate uptake in neuroblastoma cells is mediated principally by the reduced folate carrier (RFC; SLC19A1), that SLC19A1 and MYCN expression are highly correlated in both patient tumors and cell lines, and that SLC19A1 is a direct transcriptional target of N-Myc. Finally, we assessed the relationship between SLC19A1 expression and patient survival in two independent primary tumor cohorts and found that SLC19A1 expression was associated with increased risk of relapse or death, and that SLC19A1 expression retained prognostic significance independent of age, disease stage and MYCN amplification. This study adds upregulation of folate-mediated one-carbon metabolism to the known consequences of MYCN amplification, and suggests that this pathway might be targeted in poor outcome tumors with MYCN amplification and high SLC19A1 expression. PMID:25860940
In vivo and in vitro biophysical properties of hair cells from the lateral line and inner ear of developing and adult zebrafish.

PubMed

Olt, Jennifer; Johnson, Stuart L; Marcotti, Walter

2014-05-15

Hair cells detect and process sound and movement information, and transmit this with remarkable precision and efficiency to afferent neurons via specialized ribbon synapses. The zebrafish is emerging as a powerful model for genetic analysis of hair cell development and function both in vitro and in vivo. However, the full exploitation of the zebrafish is currently limited by the difficulty in obtaining systematic electrophysiological recordings from hair cells under physiological recording conditions. Thus, the biophysical properties of developing and adult zebrafish hair cells are largely unknown. We investigated potassium and calcium currents, voltage responses and synaptic activity in hair cells from the lateral line and inner ear in vivo and using near-physiological in vitro recordings. We found that the basolateral current profile of hair cells from the lateral line becomes more segregated with age, and that cells positioned in the centre of the neuromast show more mature characteristics and those towards the edge retain a more immature phenotype. The proportion of mature-like hair cells within a given neuromast increased with zebrafish development. Hair cells from the inner ear showed a developmental change in current profile between the juvenile and adult stages. In lateral line hair cells from juvenile zebrafish, exocytosis also became more efficient and required less calcium for vesicle fusion. In hair cells from mature zebrafish, the biophysical characteristics of ion channels and exocytosis resembled those of hair cells from other lower vertebrates and, to some extent, those in the immature mammalian vestibular and auditory systems. We show that although the zebrafish provides a suitable animal model for studies on hair cell physiology, it is advisable to consider that the age at which the majority of hair cells acquire a mature-type configuration is reached only in the juvenile lateral line and in the inner ear from >2 months after hatching. © 2014 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.
Transient Tcf3 Gene Repression by TALE-Transcription Factor Targeting.

PubMed

Masuda, Junko; Kawamoto, Hiroshi; Strober, Warren; Takayama, Eiji; Mizutani, Akifumi; Murakami, Hiroshi; Ikawa, Tomokatsu; Kitani, Atsushi; Maeno, Narumi; Shigehiro, Tsukasa; Satoh, Ayano; Seno, Akimasa; Arun, Vaidyanath; Kasai, Tomonari; Fuss, Ivan J; Katsura, Yoshimoto; Seno, Masaharu

2016-12-01

Transplantation of hematopoietic stem and progenitor cells (HSCs) i.e., self-renewing cells that retain multipotentiality, is now a widely performed therapy for many hematopoietic diseases. However, these cells are present in low number and are subject to replicative senescence after extraction; thus, the acquisition of sufficient numbers of cells for transplantation requires donors able to provide repetitive blood samples and/or methods of expanding cell numbers without disturbing cell multipotentiality. Previous studies have shown that HSCs maintain their multipotentiality and self-renewal activity if TCF3 transcription function is blocked under B cell differentiating conditions. Taking advantage of this finding to devise a new approach to HSC expansion in vitro, we constructed an episomal expression vector that specifically targets and transiently represses the TCF3 gene. This consisted of a vector encoding a transcription activator-like effector (TALE) fused to a Krüppel-associated box (KRAB) repressor. We showed that this TALE-KRAB vector repressed expression of an exogenous reporter gene in HEK293 and COS-7 cell lines and, more importantly, efficiently repressed endogenous TCF3 in a human B lymphoma cell line. These findings suggest that this vector can be used to maintain multipotentiality in HSC being subjected to a long-term expansion regimen prior to transplantation.
Spheroid Culture of Head and Neck Cancer Cells Reveals an Important Role of EGFR Signalling in Anchorage Independent Survival.

PubMed

Braunholz, Diana; Saki, Mohammad; Niehr, Franziska; Öztürk, Merve; Borràs Puértolas, Berta; Konschak, Robert; Budach, Volker; Tinhofer, Ingeborg

2016-01-01

In solid tumours millions of cells are shed into the blood circulation each day. Only a subset of these circulating tumour cells (CTCs) survive, many of them presumable because of their potential to form multi-cellular clusters also named spheroids. Tumour cells within these spheroids are protected from anoikis, which allows them to metastasize to distant organs or re-seed at the primary site. We used spheroid cultures of head and neck squamous cell carcinoma (HNSCC) cell lines as a model for such CTC clusters for determining the role of the epidermal growth factor receptor (EGFR) in cluster formation ability and cell survival after detachment from the extra-cellular matrix. The HNSCC cell lines FaDu, SCC-9 and UT-SCC-9 (UT-SCC-9P) as well as its cetuximab (CTX)-resistant sub-clone (UT-SCC-9R) were forced to grow in an anchorage-independent manner by coating culture dishes with the anti-adhesive polymer poly-2-hydroxyethylmethacrylate (poly-HEMA). The extent of apoptosis, clonogenic survival and EGFR signalling under such culture conditions was evaluated. The potential of spheroid formation in suspension culture was found to be positively correlated with the proliferation rate of HNSCC cell lines as well as their basal EGFR expression levels. CTX and gefitinib blocked, whereas the addition of EGFR ligands promoted anchorage-independent cell survival and spheroid formation. Increased spheroid formation and growth were associated with persistent activation of EGFR and its downstream signalling component (MAPK/ERK). Importantly, HNSCC cells derived from spheroid cultures retained their clonogenic potential in the absence of cell-matrix contact. Addition of CTX under these conditions strongly inhibited colony formation in CTX-sensitive cell lines but not their resistant subclones. Altogether, EGFR activation was identified as crucial factor for anchorage-independent survival of HNSCC cells. Targeting EGFR in CTC cluster formation might represent an attractive anti-metastatic treatment approach in HNSCC.
Neoplastic transformation of human thyroid epithelial cells by ionizing radiation

NASA Astrophysics Data System (ADS)

Herceg, Zdenko

Neoplastic transformation of human thyroid epithelial cells has been investigated following exposure to ionizing radiation in vitro. The effects of radiation type, irradiation regime, and postirradiation passaging were examined using a human thyroid epithelial cell line, designated HToriS, which was previously immortalized with SV40 genome. Exponentially growing HToriS cells were irradiated with graded doses of 137 Cs gamma- and 238pu alpha-irradiation. Cells were irradiated with either a single or multiple doses of 0.5, 1, 2, 3, or 4 Gy gamma-radiation, or single doses of 0.125, 0.25, 0.5, 1, or 1.5 Gy gamma-radiation. Following passaging, the cells were transplanted into the athymic nude mice, and the animals were screened for tumour formation. Statistically significant increases in tumour incidence were obtained with both gamma- and alpha-irradiation and with both single and multiple irradiation regimes as compared with the un-irradiated group. Regardless of radiation type and or radiation regime there appears to be a trend, with increasing doses of radiation, in which tumour incidence increases and reaches a maximum, after which the tumour incidence decreases. Tumours were characterized by histopathological examination as undifferentiated carcinomas. Investigation of expression time following irradiation demonstrated that post-irradiation passaging, generally regarded as a critical step for expression of radiation-induced DNA damage, was not a prerequisite for the neoplastic conversion of irradiated cells with this system. Cell lines were established from the tumours and their identification and characterization carried out. All cell lines established were determined to be derived from the parent HTori3 cells by DNA fingerprinting, karyotype analysis, cytokeratin staining, and SV40 large T-antigen staining. Tumorigenicity of the cell lines was confirmed by retransplantation. Comparison of the morphology in vitro showed that the tumour cell lines retained the basic epithelial morphology of the parent HToriS cells. Investigation of radiosensitivity showed that none of the 6 tumour cell lines examined had a higher radiosensitivity compared to the parent HToriS cells. This excludes the possibility that the observed transformation was the result of the selection of a pre-existing transformed subpopulation of the parent cells but that radiation-induced transformants were being induced de novo. The tumour cell lines were screened for mutations in H- and K-ras oncogenes using restriction enzyme analysis of PCR amplified DNA. No mutations were detected in 26 tumour cell lines suggesting that mutations in these two genes do not appear to be involved in radiation- induced neoplastic transformation in human thyroid epithelial cells. Screening for mutations in p53 protein using immunoprecipitation method detected no mutations in 6 tumour cell lines. This human thyroid epithelial cell line may thus be useful for the in vitro study of cellular and molecular mechanisms that are involved in human epithelial cell carcinogenesis.
Multipotent adult germ-line stem cells, like other pluripotent stem cells, can be killed by cytotoxic T lymphocytes despite low expression of major histocompatibility complex class I molecules

PubMed Central

Dressel, Ralf; Guan, Kaomei; Nolte, Jessica; Elsner, Leslie; Monecke, Sebastian; Nayernia, Karim; Hasenfuss, Gerd; Engel, Wolfgang

2009-01-01

Background Multipotent adult germ-line stem cells (maGSCs) represent a new pluripotent cell type that can be derived without genetic manipulation from spermatogonial stem cells (SSCs) present in adult testis. Similarly to induced pluripotent stem cells (iPSCs), they could provide a source of cellular grafts for new transplantation therapies of a broad variety of diseases. To test whether these stem cells can be rejected by the recipients, we have analyzed whether maGSCs and iPSCs can become targets for cytotoxic T lymphocytes (CTL) or whether they are protected, as previously proposed for embryonic stem cells (ESCs). Results We have observed that maGSCs can be maintained in prolonged culture with or without leukemia inhibitory factor and/or feeder cells and still retain the capacity to form teratomas in immunodeficient recipients. They were, however, rejected in immunocompetent allogeneic recipients, and the immune response controlled teratoma growth. We analyzed the susceptibility of three maGSC lines to CTL in comparison to ESCs, iPSCs, and F9 teratocarcinoma cells. Major histocompatibility complex (MHC) class I molecules were not detectable by flow cytometry on these stem cell lines, apart from low levels on one maGSC line (maGSC Stra8 SSC5). However, using a quantitative real time PCR analysis H2K and B2m transcripts were detected in all pluripotent stem cell lines. All pluripotent stem cell lines were killed in a peptide-dependent manner by activated CTLs derived from T cell receptor transgenic OT-I mice after pulsing of the targets with the SIINFEKL peptide. Conclusion Pluripotent stem cells, including maGSCs, ESCs, and iPSCs can become targets for CTLs, even if the expression level of MHC class I molecules is below the detection limit of flow cytometry. Thus they are not protected against CTL-mediated cytotoxicity. Therefore, pluripotent cells might be rejected after transplantation by this mechanism if specific antigens are presented and if specific activated CTLs are present. Our results show that the adaptive immune system has in principle the capacity to kill pluripotent and teratoma forming stem cells. This finding might help to develop new strategies to increase the safety of future transplantations of in vitro differentiated cells by exploiting a selective immune response against contaminating undifferentiated cells. Reviewers This article was reviewed by Bhagirath Singh, Etienne Joly and Lutz Walter. PMID:19715575
A gene expression profile indicative of early stage HER2 targeted therapy response.

PubMed

O'Neill, Fiona; Madden, Stephen F; Clynes, Martin; Crown, John; Doolan, Padraig; Aherne, Sinéad T; O'Connor, Robert

2013-07-01

Efficacious application of HER2-targetting agents requires the identification of novel predictive biomarkers. Lapatinib, afatinib and neratinib are tyrosine kinase inhibitors (TKIs) of HER2 and EGFR growth factor receptors. A panel of breast cancer cell lines was treated with these agents, trastuzumab, gefitinib and cytotoxic therapies and the expression pattern of a specific panel of genes using RT-PCR was investigated as a potential marker of early drug response to HER2-targeting therapies. Treatment of HER2 TKI-sensitive SKBR3 and BT474 cell lines with lapatinib, afatinib and neratinib induced an increase in the expression of RB1CC1, ERBB3, FOXO3a and NR3C1. The response directly correlated with the degree of sensitivity. This expression pattern switched from up-regulated to down-regulated in the HER2 expressing, HER2-TKI insensitive cell line MDAMB453. Expression of the CCND1 gene demonstrated an inversely proportional response to drug exposure. A similar expression pattern was observed following the treatment with both neratinib and afatinib. These patterns were retained following exposure to traztuzumab and lapatinib plus capecitabine. In contrast, gefitinib, dasatinib and epirubicin treatment resulted in a completely different expression pattern change. In these HER2-expressing cell line models, lapatinib, neratinib, afatinib and trastuzumab treatment generated a characteristic and specific gene expression response, proportionate to the sensitivity of the cell lines to the HER2 inhibitor.Characterisation of the induced changes in expression levels of these genes may therefore give a valuable, very early predictor of the likely extent and specificity of tumour HER2 inhibitor response in patients, potentially guiding more specific use of these agents.

A gene expression profile indicative of early stage HER2 targeted therapy response

PubMed Central

2013-01-01

Background Efficacious application of HER2-targetting agents requires the identification of novel predictive biomarkers. Lapatinib, afatinib and neratinib are tyrosine kinase inhibitors (TKIs) of HER2 and EGFR growth factor receptors. A panel of breast cancer cell lines was treated with these agents, trastuzumab, gefitinib and cytotoxic therapies and the expression pattern of a specific panel of genes using RT-PCR was investigated as a potential marker of early drug response to HER2-targeting therapies. Results Treatment of HER2 TKI-sensitive SKBR3 and BT474 cell lines with lapatinib, afatinib and neratinib induced an increase in the expression of RB1CC1, ERBB3, FOXO3a and NR3C1. The response directly correlated with the degree of sensitivity. This expression pattern switched from up-regulated to down-regulated in the HER2 expressing, HER2-TKI insensitive cell line MDAMB453. Expression of the CCND1 gene demonstrated an inversely proportional response to drug exposure. A similar expression pattern was observed following the treatment with both neratinib and afatinib. These patterns were retained following exposure to traztuzumab and lapatinib plus capecitabine. In contrast, gefitinib, dasatinib and epirubicin treatment resulted in a completely different expression pattern change. Conclusions In these HER2-expressing cell line models, lapatinib, neratinib, afatinib and trastuzumab treatment generated a characteristic and specific gene expression response, proportionate to the sensitivity of the cell lines to the HER2 inhibitor. Characterisation of the induced changes in expression levels of these genes may therefore give a valuable, very early predictor of the likely extent and specificity of tumour HER2 inhibitor response in patients, potentially guiding more specific use of these agents. PMID:23816254
Protein and Genetic Composition of Four Chromatin Types in Drosophila melanogaster Cell Lines.

PubMed

Boldyreva, Lidiya V; Goncharov, Fyodor P; Demakova, Olga V; Zykova, Tatyana Yu; Levitsky, Victor G; Kolesnikov, Nikolay N; Pindyurin, Alexey V; Semeshin, Valeriy F; Zhimulev, Igor F

2017-04-01

Recently, we analyzed genome-wide protein binding data for the Drosophila cell lines S2, Kc, BG3 and Cl.8 (modENCODE Consortium) and identified a set of 12 proteins enriched in the regions corresponding to interbands of salivary gland polytene chromosomes. Using these data, we developed a bioinformatic pipeline that partitioned the Drosophila genome into four chromatin types that we hereby refer to as aquamarine, lazurite, malachite and ruby. Here, we describe the properties of these chromatin types across different cell lines. We show that aquamarine chromatin tends to harbor transcription start sites (TSSs) and 5' untranslated regions (5'UTRs) of the genes, is enriched in diverse "open" chromatin proteins, histone modifications, nucleosome remodeling complexes and transcription factors. It encompasses most of the tRNA genes and shows enrichment for non-coding RNAs and miRNA genes. Lazurite chromatin typically encompasses gene bodies. It is rich in proteins involved in transcription elongation. Frequency of both point mutations and natural deletion breakpoints is elevated within lazurite chromatin. Malachite chromatin shows higher frequency of insertions of natural transposons. Finally, ruby chromatin is enriched for proteins and histone modifications typical for the "closed" chromatin. Ruby chromatin has a relatively low frequency of point mutations and is essentially devoid of miRNA and tRNA genes. Aquamarine and ruby chromatin types are highly stable across cell lines and have contrasting properties. Lazurite and malachite chromatin types also display characteristic protein composition, as well as enrichment for specific genomic features. We found that two types of chromatin, aquamarine and ruby, retain their complementary protein patterns in four Drosophila cell lines.
Differential Nanos 2 protein stability results in selective germ cell accumulation in the sea urchin

PubMed Central

Oulhen, Nathalie; Wessel, Gary M.

2016-01-01

Nanos is a translational regulator required for the survival and maintenance of primordial germ cells. In the sea urchin, Strongylocentrotus purpuratus (Sp), Nanos 2 mRNA is broadly transcribed but accumulates specifically in the small micromere (sMic) lineage, in part because of the 3′UTR element GNARLE leads to turnover in somatic cells but retention in the sMics. Here we found that the Nanos 2 protein is also selectively stabilized; it is initially translated throughout the embryo but turned over in the future somatic cells and retained only in the sMics, the future germ line in this animal. This differential stability of Nanos protein is dependent on the open reading frame (ORF), and is independent of the sumoylation and ubiquitylation pathways. Manipulation of the ORF indicates that 68 amino acids in the N terminus of the Nanos protein are essential for its stability in the sMics whereas a 45 amino acid element adjacent to the zinc fingers targets its degradation. Further, this regulation of Nanos protein is cell autonomous, following formation of the germ line. These results are paradigmatic for the unique presence of Nanos in the germ line by a combination of selective RNA retention, distinctive translational control mechanisms (Oulhen et al., 2013), and now also by defined Nanos protein stability. PMID:27424271
Differential Nanos 2 protein stability results in selective germ cell accumulation in the sea urchin.

PubMed

Oulhen, Nathalie; Wessel, Gary M

2016-10-01

Nanos is a translational regulator required for the survival and maintenance of primordial germ cells. In the sea urchin, Strongylocentrotus purpuratus (Sp), Nanos 2 mRNA is broadly transcribed but accumulates specifically in the small micromere (sMic) lineage, in part because of the 3'UTR element GNARLE leads to turnover in somatic cells but retention in the sMics. Here we found that the Nanos 2 protein is also selectively stabilized; it is initially translated throughout the embryo but turned over in the future somatic cells and retained only in the sMics, the future germ line in this animal. This differential stability of Nanos protein is dependent on the open reading frame (ORF), and is independent of the sumoylation and ubiquitylation pathways. Manipulation of the ORF indicates that 68 amino acids in the N terminus of the Nanos protein are essential for its stability in the sMics whereas a 45 amino acid element adjacent to the zinc fingers targets its degradation. Further, this regulation of Nanos protein is cell autonomous, following formation of the germ line. These results are paradigmatic for the unique presence of Nanos in the germ line by a combination of selective RNA retention, distinctive translational control mechanisms (Oulhen et al., 2013), and now also by defined Nanos protein stability. Copyright © 2016 Elsevier Inc. All rights reserved.
Method Of Bonding A Metal Connection To An Electrode Including A Core Having A Fiber Or Foam Type Structure For An Electrochemical Cell, An

DOEpatents

Loustau, Marie-Therese; Verhoog, Roelof; Precigout, Claude

1996-09-24

A method of bonding a metal connection to an electrode including a core having a fiber or foam-type structure for an electrochemical cell, in which method at least one metal strip is pressed against one edge of the core and is welded thereto under compression, wherein, at least in line with the region in which said strip is welded to the core, which is referred to as the "main core", a retaining core of a type analogous to that of the main core is disposed prior to the welding.
Infection of human T lymphotropic virus-I-specific immune T cell clones by human T lymphotropic virus-I.

PubMed Central

Mitsuya, H; Jarrett, R F; Cossman, J; Cohen, O J; Kao, C S; Guo, H G; Reitz, M S; Broder, S

1986-01-01

Human T lymphotropic virus-I (HTLV-I)-specific T cell lines were established and cloned. K5, an OKT8+ clone bearing multiple proviral integration sites, retained its HTLV-I-specific cytotoxicity and a normal dependence on interleukin 2 (IL-2), indicating that there is a finite number of transforming integration sites. R2, an OKT4+ HTLV-I-infected clone, initially mounted a proliferative response to HTLV-I; but then its IL-2-independent proliferation increased and the antigen specificity was lost. All HTLV-I-infected clones tested including K7, another OKT8+ transformed cytotoxic clone that had lost its reactivity, expressed comparable levels of T cell receptor beta-chain (TCR-beta) messenger (m)RNA. Although clones K5 and K7 had different functional properties, they had the same rearrangement of the TCR-beta gene, suggesting that they had the same clonal origin. These data indicate that HTLV-I-specific T cells retain their immune reactivity for variable periods of time following infection, but then usually lose it; in some cases, however, no alteration in function can be detected. The data also suggest that different consequences can take place in the same clone depending on the pattern of retroviral infection. Images PMID:2877011
ENU Mutagenesis in Mice Identifies Candidate Genes For Hypogonadism

PubMed Central

Weiss, Jeffrey; Hurley, Lisa A.; Harris, Rebecca M.; Finlayson, Courtney; Tong, Minghan; Fisher, Lisa A.; Moran, Jennifer L.; Beier, David R.; Mason, Christopher; Jameson, J. Larry

2012-01-01

Genome-wide mutagenesis was performed in mice to identify candidate genes for male infertility, for which the predominant causes remain idiopathic. Mice were mutagenized using N-ethyl-N-nitrosourea (ENU), bred, and screened for phenotypes associated with the male urogenital system. Fifteen heritable lines were isolated and chromosomal loci were assigned using low density genome-wide SNP arrays. Ten of the fifteen lines were pursued further using higher resolution SNP analysis to narrow the candidate gene regions. Exon sequencing of candidate genes identified mutations in mice with cystic kidneys (Bicc1), cryptorchidism (Rxfp2), restricted germ cell deficiency (Plk4), and severe germ cell deficiency (Prdm9). In two other lines with severe hypogonadism candidate sequencing failed to identify mutations, suggesting defects in genes with previously undocumented roles in gonadal function. These genomic intervals were sequenced in their entirety and a candidate mutation was identified in SnrpE in one of the two lines. The line harboring the SnrpE variant retains substantial spermatogenesis despite small testis size, an unusual phenotype. In addition to the reproductive defects, heritable phenotypes were observed in mice with ataxia (Myo5a), tremors (Pmp22), growth retardation (unknown gene), and hydrocephalus (unknown gene). These results demonstrate that the ENU screen is an effective tool for identifying potential causes of male infertility. PMID:22258617
Antibody-Directed Cytotoxic Agents: Use of Monoclonal Antibody to Direct the Action of Toxin A Chains to Colorectal Carcinoma Cells

NASA Astrophysics Data System (ADS)

Gilliland, D. Gary; Steplewski, Zenon; Collier, R. John; Mitchell, Kenneth F.; Chang, Tong H.; Koprowski, Hilary

1980-08-01

We have constructed cell-specific cytotoxic agents by covalently coupling the A chain from diphtheria toxin or ricin toxin to monoclonal antibody directed against a colorectal carcinoma tumor-associated antigen. Antibody 1083-17-1A was modified by attachment of 3-(2-pyridyldithio)propionyl or cystaminyl groups and then treated with reduced A chain to give disulfide-linked conjugates that retained the original binding specificity of the antibody moiety. The conjugates showed cytotoxic activity for colorectal carcinoma cells in culture, but were not toxic in the same concentration range for a variety of cell lines that lacked the antigen. Under defined conditions virtually 100% of antigen-bearing cultured cells were killed, whereas cells that lacked the antigen were not affected. Conjugates containing toxin A chains coupled to monoclonal antibodies may be useful in studying functions of various cell surface components and, possibly, as tumor-specific therapeutic agents.
Establishment and evaluation of a stable steroidogenic goat Leydig cell line.

PubMed

Zhou, Jinhua; Dai, Rui; Lei, Lanjie; Lin, Pengfei; Lu, Xiaolong; Wang, Xiangguo; Tang, Keqiong; Wang, Aihua; Jin, Yaping

2016-04-01

Leydig cells play a key role in synthesizing androgen and regulating spermatogenesis. The dysfunction of Leydig cells may lead to various male diseases. Although primary Leydig cell cultures have been used, their finite lifespan hinders the assessment of long-term effects. In the present study, primary goat Leydig cells (GLCs) were immortalized via the transfection of a plasmid containing the human telomerase reverse transcriptase (hTERT) gene. The expressions of hTERT and telomerase activity were evaluated in transduced GLCs (hTERT-GLCs). These cells steadily expressed the hTERT gene and exhibited longer telomere lengths at passage 55 that were similar to those of HeLa cells. The hTERT-GLCs at passages 30 and 50 expressed genes that encoded key proteins, enzymes and receptors that are inherent to normal Leydig cells, for example, steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), 3β-hydroxysteroid dehydrogenase (3β-HSD) and LH-receptor (LH-R). Additionally, the immortalized goat Leydig cells secreted detectable quantities of testosterone in response to hCG stimulation. Furthermore, this cell line appeared to proliferate more quickly than the control cells, although no neoplastic transformation occurred in vitro. We concluded that the GLCs immortalized with hTERT retained their original characteristics and might provide a useful model for the study of Leydig cell function. © 2015 Japanese Society of Animal Science.
Generation of induced pluripotent stem cells from a patient with Best Dystrophy carrying 11q12.3 (BEST1 (VMD2)) mutation.

PubMed

Hsu, Chih-Chien; Lu, Huai-En; Chuang, Jen-Hua; Ko, Yu-Ling; Tsai, Yi-Ching; Tai, Hsiao-Yun; Yarmishyn, Aliaksandr A; Hwang, De-Kuang; Wang, Mong-Lien; Yang, Yi-Ping; Chen, Shih-Jen; Peng, Chi-Hsien; Chiou, Shih-Hwa; Lin, Tai-Chi

2018-04-03

Best disease (BD), also termed Best vitelliform macular dystrophy (BVMD), is a juvenile-onset form of macular degeneration and central visual loss. In this report, we generated an induced pluripotent stem cell (iPSC) line, TVGH-iPSC-012-04, from the peripheral blood mononuclear cells of a female patient with BD by using the Sendai virus delivery system. The resulting iPSCs retained the disease-causing DNA mutation, expressed pluripotent markers and could differentiate into three germ layers. We believe that BD patient-specific iPSCs provide a powerful in vitro model for evaluating the pathological phenotypes of the disease. Copyright © 2018. Published by Elsevier B.V.
Molecular basis underlying resistance to Mps1/TTK inhibitors

PubMed Central

Koch, A; Maia, A; Janssen, A; Medema, R H

2016-01-01

Mps1/TTK is a dual-specificity kinase, with an essential role in mitotic checkpoint signaling, which has emerged as a potential target in cancer therapy. Several Mps1/TTK small-molecule inhibitors have been described that exhibit promising activity in cell culture and xenograft models. Here, we investigated whether cancer cells can develop resistance to these drugs. To this end, we treated various cancer cell lines with sublethal concentrations of a potent Mps1/TTK inhibitor in order to isolate inhibitor-resistant monoclonal cell lines. We identified four point mutations in the catalytic domain of Mps1/TTK that gave rise to inhibitor resistance but retained wild-type catalytic activity. Interestingly, cross-resistance of the identified mutations to other Mps1/TTK inhibitors is limited. Our studies predict that Mps1/TTK inhibitor-resistant tumor cells can arise through the acquisition of mutations in the adenosine triphosphate-binding pocket of the kinase that prevent stable binding of the inhibitors. In addition, our results suggest that combinations of inhibitors could be used to prevent acquisition of drug resistance. Interestingly, cross-resistance seems nonspecific for inhibitor scaffolds, a notion that can be exploited in future drug design to evict possible resistance mutations during clinical treatment. PMID:26364596
Molecular basis underlying resistance to Mps1/TTK inhibitors.

PubMed

Koch, A; Maia, A; Janssen, A; Medema, R H

2016-05-12

Mps1/TTK is a dual-specificity kinase, with an essential role in mitotic checkpoint signaling, which has emerged as a potential target in cancer therapy. Several Mps1/TTK small-molecule inhibitors have been described that exhibit promising activity in cell culture and xenograft models. Here, we investigated whether cancer cells can develop resistance to these drugs. To this end, we treated various cancer cell lines with sublethal concentrations of a potent Mps1/TTK inhibitor in order to isolate inhibitor-resistant monoclonal cell lines. We identified four point mutations in the catalytic domain of Mps1/TTK that gave rise to inhibitor resistance but retained wild-type catalytic activity. Interestingly, cross-resistance of the identified mutations to other Mps1/TTK inhibitors is limited. Our studies predict that Mps1/TTK inhibitor-resistant tumor cells can arise through the acquisition of mutations in the adenosine triphosphate-binding pocket of the kinase that prevent stable binding of the inhibitors. In addition, our results suggest that combinations of inhibitors could be used to prevent acquisition of drug resistance. Interestingly, cross-resistance seems nonspecific for inhibitor scaffolds, a notion that can be exploited in future drug design to evict possible resistance mutations during clinical treatment.
Preclinical Analysis of Fetal Human Mesencephalic Neural Progenitor Cell Lines: Characterization and Safety In Vitro and In Vivo

PubMed Central

Moon, Jisook; Schwarz, Sigrid C.; Lee, Hyun‐Seob; Kang, Jun Mo; Lee, Young‐Eun; Kim, Bona; Sung, Mi‐Young; Höglinger, Günter; Wegner, Florian; Kim, Jin Su; Chung, Hyung‐Min; Chang, Sung Woon; Cha, Kwang Yul; Kim, Kwang‐Soo

2016-01-01

Abstract We have developed a good manufacturing practice for long‐term cultivation of fetal human midbrain‐derived neural progenitor cells. The generation of human dopaminergic neurons may serve as a tool of either restorative cell therapies or cellular models, particularly as a reference for phenotyping region‐specific human neural stem cell lines such as human embryonic stem cells and human inducible pluripotent stem cells. We cultivated 3 different midbrain neural progenitor lines at 10, 12, and 14 weeks of gestation for more than a year and characterized them in great detail, as well as in comparison with Lund mesencephalic cells. The whole cultivation process of tissue preparation, cultivation, and cryopreservation was developed using strict serum‐free conditions and standardized operating protocols under clean‐room conditions. Long‐term‐cultivated midbrain‐derived neural progenitor cells retained stemness, midbrain fate specificity, and floorplate markers. The potential to differentiate into authentic A9‐specific dopaminergic neurons was markedly elevated after prolonged expansion, resulting in large quantities of functional dopaminergic neurons without genetic modification. In restorative cell therapeutic approaches, midbrain‐derived neural progenitor cells reversed impaired motor function in rodents, survived well, and did not exhibit tumor formation in immunodeficient nude mice in the short or long term (8 and 30 weeks, respectively). We conclude that midbrain‐derived neural progenitor cells are a promising source for human dopaminergic neurons and suitable for long‐term expansion under good manufacturing practice, thus opening the avenue for restorative clinical applications or robust cellular models such as high‐content or high‐throughput screening. Stem Cells Translational Medicine 2017;6:576–588 PMID:28191758
Establishment and characterization of a cell line from human adenoid cystic carcinoma of the lacrimal glands and a nude mouse transplantable model.

PubMed

Lin, Tingting; Zhu, Limin; Zhou, Beiqing; Xie, Lianfeng; Lv, Jianmei; Dong, Lijie; He, Yanjin

2015-06-01

Using tissue block culture techniques, we established a new human tumor cell line derived from adenoid cystic carcinoma of the lacrimal glands (LACC-1). The LACC-1 cell line was successfully subcultured for more than 100 passages during the last two years. The outgrowth of cells was observed by day 5 after seeding, and then the cells were generated slowly. The first passage proceeded by day 32, and the classical epithelioid cell colonies formed by day 69 after inoculation. After eight passages, homogeneous epithelioid tumor cells appeared when we combined continuous passage, mechanical scraping, repeated adherence, and dissociation methods to remove the fibroblast cells. LACC-1 cells appeared as a histologically solid pattern and continuous passage culture. The population doubling time was approximately 37.1 h. LACC-1 cells appeared as an epithelioid monolayer culture on the cell culture flask and presented with a cobblestone-like appearance when they reached confluency. The nucleus was large and round with many abnormal mitoses. The nucleoplasm ratio was high. Multinucleated tumor giant cells appeared. LACC-1 cells showed a tendency to have overlapping growth without contact inhibition when the cell density continued to increase. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that the LACC-1 cells were malignant tumor cells that were poorly differentiated. The surface of the LACC-1 cells exhibited affluent microvilli, protuberances and filopodia under SEM. The no. 84 generation LACC-1 cell line was inoculated subcutaneously into the subaxillary of nude mice and the tumorigenic potential was evident. The formation rate of the transplanted tumors was 100% at day 7 after inoculation. This finding showed that the LACC-1 cell line was malignant with tumorigenic ability. The xenograft tumors retained the same histological characteristics of a solid pattern as the LACC-1 original tumor after inoculation for 49 days. Under TEM observation, the xenograft tumor cells had the same ultrastructure as the LACC-1 cells. Immunohistochemical examination revealed the similarity of both cytoskeletal proteins (e.g., cytokeratin, vimentin, desmin and α-SMA) and S-100 expression in the original tumor, LACC-1 cells and xenograft tumors. Immunoreactivity of these proteins was gradually decreased in these three tissues. Reverse transcription-polymerase chain reaction demonstrated that the xenograft tumors originated from the human. Based on these results, the LACC-1 cell line provides a useful model for studying the biological characteristics of human ACC of the lacrimal glands.
Proteasome inhibition blocks NF-κB and ERK1/2 pathways, restores antigen expression and sensitizes resistant human melanoma to TCR-engineered CTLs

PubMed Central

Jazirehi, Ali R.; Economou, James S.

2012-01-01

Adoptive cell transfer (ACT) of ex vivo engineered autologous lymphocytes encoding high-affinity MART-1/HLA-A*0201-specific T-cell receptor (TCR) α/β chains (F5 CTL), densely infiltrate into sites of metastatic disease, mediating dramatic but partial clinical responses in melanoma patients. We hypothesized that MART-1 down-modulation in addition to aberrant apoptotic/survival signaling could confer resistance to death signals delivered by transgenic CTLs. To explore this hypothesis, we established an in vitro model of resistant (R) lines from MART-1+/HLA-A*0201+ F5 CTL-sensitive parental (P) lines under serial F5 CTL-selective pressure. We have recently reported that several melanoma R lines, while retaining MART-1 expression, exhibited constitutive NF-κB activation and over-expression of NF-κB-dependent resistance factors. Another established melanoma cell line M244, otherwise sensitive to F5 CTL, yielded R lines after serial F5 CTL selective pressure which had both reduced MART-1 expression levels, thus, could not be recognized, and were resistant to CTL-delivered apoptotic death signals. The proteasome inhibitor bortezomib blocked NF-κB activity, decreased phopspho-ERK1/2, increased phospho-JNK levels, reduced expression of resistance-factors, restored MART-1 expression to sufficient levels, which in combination allowed M244R lines be sensitized to F5 CTL-killing. These findings suggest that proteasome inhibition in immune resistant tumors can restore proapoptotic signaling and improve tumor antigen expression. PMID:22532603
Glial cell line-derived neurotrophic factor and endothelial cells promote self-renewal of rabbit germ cells with spermatogonial stem cell properties.

PubMed

Kubota, Hiroshi; Wu, Xin; Goodyear, Shaun M; Avarbock, Mary R; Brinster, Ralph L

2011-08-01

Previous studies suggest that exogenous factors crucial for spermatogonial stem cell (SSC) self-renewal are conserved among several mammalian species. Since glial cell line-derived neurotrophic factor (GDNF) and fibroblast growth factor 2 (FGF2) are critical for rodent SSC self-renewal, we hypothesized that they might promote self-renewal of nonrodent SSCs. Therefore, we cultured testicular germ cells from prepubertal rabbits in the presence of GDNF and FGF2 and found they proliferated indefinitely as cellular clumps that displayed characteristics previously identified for rodent SSCs. The rabbit germ cells could not be maintained on mouse embryonic fibroblast (STO) feeders that support rodent SSC self-renewal in vitro but were rather supported on mouse yolk sac-derived endothelial cell (C166) feeder layers. Proliferation of rabbit germ cells was dependent on GDNF. Of critical importance was that clump-forming rabbit germ cells colonized seminiferous tubules of immunodeficient mice, proliferated for at least 6 mo, while retaining an SSC phenotype in the testes of recipient mice, indicating that they were rabbit SSCs. This study demonstrates that GDNF is a mitogenic factor promoting self-renewal that is conserved between rodent and rabbit SSCs; with an evolutionary separation of ∼ 60 million years. These findings provide a foundation to study the mechanisms governing SSC self-renewal in nonrodent species.
PHYSIOLOGICAL, CYTOLOGICAL AND BIOCHEMICAL STABILITY OF Medicago sativa L. CELL CULTURE AFTER 27 YEARS OF CRYOGENIC STORAGE.

PubMed

Volkova, L A; Urmantseva, V V; Popova, E V; Nosov, A M

2015-01-01

The efficiency of long-term cryogenic storage to prevent somaclonal variations in plant cell cultures and retain their major cytogenetic and biochemical traits remains under debate. In particular, it is not clear how stress conditions associated with cryopreservation, such as low temperature, dehydration and toxic action of some cryoprotectants (DMSO in particular), affect post-storage regrowth and genetic integrity of cell samples. We assessed growth, cytogenetic and biochemical characteristics of the peroxidase-producing strain of Medicago sativa L. cell culture recovered after 27 years of cryogenic storage as compared to the same culture before cryopreservation. In 1984, M. sativa L. cell culture was cryopreserved using programmed freezing and 7% DMSO as a cryoprotectant. In 2011, after rewarming in a water bath at 40 degree C for 90 s, cell culture was recovered and proliferated. Viability, growth profile, mitotic index, ploidy level, peroxidase activity and cell response to hypothermia and osmotic stress were compared between the recovered and the initial cell cultures using the records available from 1984. Viability of alfalfa cell culture after rewarming was below 20% but it increased to 80% by the 27th subculture cycle. Recovered culture showed higher mitotic activity and increased number of haploid and diploid cells compared to the initial cell line. Both peroxidase activity and response to abiotic stress in the recovered cell culture were similar to that of the initial culture. Cryopreservation by programmed freezing was effective at retaining the main characteristics of M. sativa undifferentiated cell culture after 27 years of storage. According to available data, this is longest period of successful cryopreservation of plant cell cultures reported so far. After storage, there was no evidence that DMSO had any detrimental effect on cell viability, growth or cytogenetics.
Functional somatostatin receptors on a rat pancreatic acinar cell line

DOE Office of Scientific and Technical Information (OSTI.GOV)

Viguerie, N.; Tahiri-Jouti, N.; Esteve, J.P.

1988-07-01

Somatostatin receptors from a rat pancreatic acinar cell line, AR4-2J, were characterized biochemically, structurally, and functionally. Binding of {sup 125}I-(Tyr{sup 11})Somatostatin to AR4-2J cells was saturable, exhibiting a single class of high-affinity binding sites with a maximal binding capacity of 258 {plus minus} 20 fmol/10{sup 6} cells. Somatostatin receptor structure was analyzed by covalently cross-linking {sup 125}I-(Tyr{sup 11})somatostatin to its plasma membrane receptors. Gel electrophoresis and autoradiography of cross-linked proteins revealed a peptide containing the somatostatin receptor. Somatostatin inhibited vasoactive intestinal peptide (VIP)-stimulated adenosine 3{prime},5{prime}-cyclic monophosphate (cAMP) formation in a dose-dependent manner. The concentration of somatostatin that caused half-maximal inhibitionmore » of cAMP formation was close to the receptor affinity for somatostatin. Pertussis toxin pretreatment of AR4-2J cells prevented somatostatin inhibition of VIP-stimulated cAMP formation as well as somatostatin binding. The authors conclude that AR4-2J cells exhibit functional somatostatin receptors that retain both specificity and affinity of the pancreatic acinar cell somatostatin receptors and act via the pertussis toxin-sensitive guanine nucleotide-binding protein N{sub i} to inhibit adenylate cyclase.« less
Generation of an expandable intermediate mesoderm restricted progenitor cell line from human pluripotent stem cells

PubMed Central

Kumar, Nathan; Richter, Jenna; Cutts, Josh; Bush, Kevin T; Trujillo, Cleber; Nigam, Sanjay K; Gaasterland, Terry; Brafman, David; Willert, Karl

2015-01-01

The field of tissue engineering entered a new era with the development of human pluripotent stem cells (hPSCs), which are capable of unlimited expansion whilst retaining the potential to differentiate into all mature cell populations. However, these cells harbor significant risks, including tumor formation upon transplantation. One way to mitigate this risk is to develop expandable progenitor cell populations with restricted differentiation potential. Here, we used a cellular microarray technology to identify a defined and optimized culture condition that supports the derivation and propagation of a cell population with mesodermal properties. This cell population, referred to as intermediate mesodermal progenitor (IMP) cells, is capable of unlimited expansion, lacks tumor formation potential, and, upon appropriate stimulation, readily acquires properties of a sub-population of kidney cells. Interestingly, IMP cells fail to differentiate into other mesodermally-derived tissues, including blood and heart, suggesting that these cells are restricted to an intermediate mesodermal fate. DOI: http://dx.doi.org/10.7554/eLife.08413.001 PMID:26554899
C2-streptavidin mediates the delivery of biotin-conjugated tumor suppressor protein p53 into tumor cells.

PubMed

Fahrer, Jörg; Schweitzer, Brigitte; Fiedler, Katja; Langer, Torben; Gierschik, Peter; Barth, Holger

2013-04-17

We have previously generated a recombinant C2-streptavidin fusion protein for the delivery of biotin-labeled molecules of low molecular weight into the cytosol of mammalian cells. A nontoxic moiety of Clostridium botulinum C2 toxin mediates the cellular uptake, whereas the streptavidin unit serves as a binding platform for biotin-labeled cargo molecules. In the present study, we used the C2-streptavidin transporter to introduce biotin-conjugated p53 protein into various mammalian cell lines. The p53 tumor suppressor protein is inactivated in many human cancers by multiple mechanisms and therefore the restoration of its activity in tumor cells is of great therapeutic interest. Recombinant p53 was expressed in insect cells and biotin-labeled. Biotin-p53 retained its specific high-affinity DNA-binding as revealed by gel-shift analysis. Successful conjugation of biotin-p53 to the C2-streptavidin transporter was monitored by an overlay blot technique and confirmed by real-time surface plasmon resonance, providing a KD-value in the low nM range. C2-streptavidin significantly enhanced the uptake of biotin-p53 into African Green Monkey (Vero) epithelial cells as shown by flow cytometry. Using cell fractionation, the cytosolic translocation of biotin-p53 was detected in Vero cells as well as in HeLa cervix carcinoma cells. In line with this finding, confocal microscopy displayed cytoplasmic staining of biotin-p53 in HeLa and HL60 leukemia cells. Internalized biotin-p53 partially colocalized with early endosomes, as confirmed by confocal microscopy. In conclusion, our results demonstrate the successful conjugation of biotin-p53 to C2-streptavidin and its subsequent receptor-mediated endocytosis into different human tumor cell lines.

Neoplastic transformation of SV40-immortalized human urinary tract epithelial cells by in vitro exposure to 3-methylcholanthrene.

PubMed

Reznikoff, C A; Loretz, L J; Christian, B J; Wu, S Q; Meisner, L F

1988-08-01

Normal human urinary tract epithelial cells (HUC) were neoplastically transformed in vitro using a step-wise strategy. First, a partially transformed non-virus-producing cell line was obtained after infection of HUC with simian virus 40 (SV40). This cell line (SV-HUC-1) was demonstrated to be clonal in origin, as 100% of cells contained at least five of seven marker chromosomes. Marker chromosomes were formed by balanced translocations resulting in a 'pseudodiploid' cell line. SV-HUC-1 showed altered growth properties in vitro (e.g. anchorage independent growth) but failed to form tumors in athymic nude mice, even after 3 years in culture (80 passages). In the studies reported here, SV-HUC-1 at early passages (P15-P19) were exposed to 3-methylcholanthrene (MCA) in three separate experiments. After a six-week post-treatment period of cell culture, cells were inoculated s.c. into athymic nude mice. In all experiments, MCA-treated SV-HUC-1 formed carcinomas in mice usually with a latent period of 5-8 weeks. These carcinomas showed heterogeneity with respect to histopathologies and growth properties in the mice and karyotypes. All the tumors retained SV-HUC-1 chromosome markers, but each independent transformant was aneuploid and contained unique new marker chromosomes. Chromosomes usually altered in tumor cells included numbers 3, 5, 6, 9, 11 and 13. Mutations in the ras family of cellular proto-oncogenes resulting in altered mobility of the p21 protein product were not detected in six cell lines established from independently derived tumors. It is not yet known whether other cellular proto-oncogenes are activated in these tumorigenic transformants. Neither control SV-HUC-1 (which were not exposed to MCA), nor early passage HUC exposed to MCA formed tumors when inoculated into mice. Thus, the tumorigenic transformation of HUC resulted from the combined actions of SV40 and MCA.
Assessing stemness and proliferation properties of the newly established colon cancer 'stem' cell line, CSC480 and novel approaches to identify dormant cancer cells.

PubMed

Alowaidi, Faisal; Hashimi, Saeed Mujahid; Alqurashi, Naif; Alhulais, Reem; Ivanovski, Saso; Bellette, Bernadette; Meedenyia, Adrian; Lam, Alfred; Wood, Stephen

2018-06-01

To date two questions that remain unanswered regarding cancer are the following: i) how is it initiated, and ii) what is the role that cancer stem cells (CSCs) play in the disease process? Understanding the biology of CSCs and how they are generated is pivotal for the development of successful treatment regimens. To date, the lack of a representative cell model has prevented the successful identification and eradication of CSCs in vivo. The current methods of CSC identification are dependent on the protocol used to generate these cells, which has introduced variation and made the identification process more complicated. Furthermore, the list of possible markers is increasing in complexity. This is further confounded by the fact that there is insufficient information to determine whether the cells these markers detect are truly self‑renewing stem cells or, instead, progenitor cells. In the present study, we investigated a novel cell line model, CSC480, which can be employed to assess CSC markers and for testing novel therapeutic regimens. CSC480 cells have been revealed to express markers of CSCs such as CD44, ALDH1 and Sox2, that have lower expression in the SW480 cell line. CSC480 cells also expressed higher levels of the cancer resistance marker, ABCG2 and had higher proliferative and growth capacity than SW480 cells. In the present study, we also evaluated a novel approach to identify different cell types present in heterogeneous cancer cell populations according to their proliferative ability using the proliferation marker 5‑ethynyl‑2'‑deoxyuridine (EdU). Furthermore, using EdU, we identified dormant cells with a modified label‑retaining cell (LRC) protocol. Through this novel LRC method, we assessed newly discovered markers of stemness to ascertain their capability to identify quiescent from dividing CSCs. In conclusion, the CSC480 cell line was an important model to be used in unravelling the underlying mechanisms that control fast‑dividing and partially self‑renewing stem cells (SCs) that may give rise to cancer.
Vacuum-jacketed transfer line installation technique

NASA Technical Reports Server (NTRS)

Bowers, W. M.

1968-01-01

Rolling-type spacers in the form of steel balls retained in appropriate sleeves affixed at intervals to the exterior of the transfer line facilitate the installation of a vacuum-jacketed line. They act as standoffs to position the transfer line concentrically within the vacuum jacket line.
Anti-PD-L1/TGFβR2 (M7824) fusion protein induces immunogenic modulation of human urothelial carcinoma cell lines, rendering them more susceptible to immune-mediated recognition and lysis.

PubMed

Grenga, Italia; Donahue, Renee N; Gargulak, Morgan L; Lepone, Lauren M; Roselli, Mario; Bilusic, Marijo; Schlom, Jeffrey

2018-03-01

Avelumab has recently been approved by the Food and Drug Administration for the therapy of Merkel cell carcinoma and urothelial carcinoma. M7824 is a novel first-in-class bifunctional fusion protein comprising a monoclonal antibody against programmed death-ligand 1 (PD-L1, avelumab), fused to the extracellular domain of human transforming growth factor beta (TGFβ) receptor 2, which functions as a TGFβ "trap." Advanced urothelial tumors have been shown to express TGFβ, which possesses immunosuppressive properties that promote cancer progression and metastasis. The rationale for a combined molecule is to block the PD-1/PD-L1 interaction between tumor cells and immune cell infiltrate and simultaneously reduce or eliminate TGFβ from the tumor microenvironment. In this study, we explored the effect of M7824 on invasive urothelial carcinoma cell lines. Human urothelial (transitional cell) carcinoma cell lines HTB-4, HTB-1, and HTB-5 were treated with M7824, M7824mut (M7824 that is mutated in the anti-PD-L1 portion of the molecule and thus does not bind PD-L1), anti-PD-L1 (avelumab), or IgG1 isotype control monoclonal antibody, and were assessed for gene expression, cell-surface phenotype, and sensitivity to lysis by TRAIL, antigen-specific cytotoxic T lymphocytes and natural killer cells. M7824 retains the ability to mediate antibody-dependent cellular cytotoxicity of tumor cells, although in some cases to a lesser extent than anti-PD-L1. However, compared to anti-PD-L1, M7824 increases (A) gene expression of molecules involved in T-cell trafficking in the tumor (e.g., CXCL11), (B) TRAIL-mediated tumor cell lysis, and (C) antigen-specific CD8 + T-cell-mediated lysis of tumor cells. These studies demonstrate the immunomodulatory properties of M7824 on both tumor cell phenotype and immune-mediated lysis. Compared to anti-PD-L1 or M7824mut, M7824 induces immunogenic modulation of urothelial carcinoma cell lines, rendering them more susceptible to immune-mediated recognition and lysis. These findings show the relevance of the dual blockade of PD-L1 and TGFβ in urothelial carcinoma cell lines and thus support the rationale for future clinical studies of M7824 in patients with urothelial cancer. Published by Elsevier Inc.
A system for the measurement of gene targeting efficiency in human cell lines using an antibiotic resistance-GFP fusion gene.

PubMed

Konishi, Yuko; Karnan, Sivasundaram; Takahashi, Miyuki; Ota, Akinobu; Damdindorj, Lkhagvasuren; Hosokawa, Yoshitaka; Konishi, Hiroyuki

2012-09-01

Gene targeting in a broad range of human somatic cell lines has been hampered by inefficient homologous recombination. To improve this technology and facilitate its widespread application, it is critical to first have a robust and efficient research system for measuring gene targeting efficiency. Here, using a fusion gene consisting of hygromycin B phosphotransferase and 3'-truncated enhanced GFP (HygR-5' EGFP) as a reporter gene, we created a molecular system monitoring the ratio of homologous to random integration (H/R ratio) of targeting vectors into the genome. Cell clones transduced with a reporter vector containing HygR-5' EGFP were efficiently established from two human somatic cell lines. Established HygR-5' EGFP reporter clones retained their capacity to monitor gene targeting efficiency for a longer duration than a conventional reporter system using an unfused 5' EGFP gene. With the HygR-5' EGFP reporter system, we reproduced previous findings of gene targeting frequency being up-regulated by the use of an adeno-associated viral (AAV) backbone, a promoter-trap system, or a longer homology arm in a targeting vector, suggesting that this system accurately monitors H/R ratio. Thus, our HygR-5' EGFP reporter system will assist in the development of an efficient AAV-based gene targeting technology.
TORC1 and class I HDAC inhibitors synergize to suppress mature B cell neoplasms.

PubMed

Simmons, John K; Patel, Jyoti; Michalowski, Aleksandra; Zhang, Shuling; Wei, Bih-Rong; Sullivan, Patrick; Gamache, Ben; Felsenstein, Kenneth; Kuehl, W Michael; Simpson, R Mark; Zingone, Adriana; Landgren, Ola; Mock, Beverly A

2014-03-01

Enhanced proliferative signaling and loss of cell cycle regulation are essential for cancer progression. Increased mitogenic signaling through activation of the mTOR pathway, coupled with deregulation of the Cyclin D/retinoblastoma (Rb) pathway is a common feature of lymphoid malignancies, including plasmacytoma (PCT), multiple myeloma (MM), Burkitt's lymphoma (BL), and mantle cell lymphoma (MCL). Here we evaluate the synergy of pharmacologically affecting both of these critical pathways using the mTOR inhibitor sirolimus and the histone deacetylase inhibitor entinostat. A dose-matrix screening approach found this combination to be highly active and synergistic in a panel of genetically diverse human MM cell lines. Synergy and activity was observed in mouse PCT and human BL and MCL cell lines tested in vitro, as well as in freshly isolated primary MM patient samples tested ex vivo. This combination had minimal effects on healthy donor cells and retained activity when tested in a co-culture system simulating the protective interaction of cancer cells with the tumor microenvironment. Combining sirolimus with entinostat enhanced cell cycle arrest and apoptosis. At the molecular level, entinostat increased the expression of cell cycle negative regulators including CDKN1A (p21) and CDKN2A (p16), while the combination decreased critical growth and survival effectors including Cyclin D, BCL-XL, BIRC5, and activated MAPK. Published by Elsevier B.V.
Connective Tissue Growth Factor reporter mice label a subpopulation of mesenchymal progenitor cells that reside in the trabecular bone region.

PubMed

Wang, Wen; Strecker, Sara; Liu, Yaling; Wang, Liping; Assanah, Fayekah; Smith, Spenser; Maye, Peter

2015-02-01

Few gene markers selectively identify mesenchymal progenitor cells inside the bone marrow. We have investigated a cell population located in the mouse bone marrow labeled by Connective Tissue Growth Factor reporter expression (CTGF-EGFP). Bone marrow flushed from CTGF reporter mice yielded an EGFP+ stromal cell population. Interestingly, the percentage of stromal cells retaining CTGF reporter expression decreased with age in vivo and was half the frequency in females compared to males. In culture, CTGF reporter expression and endogenous CTGF expression marked the same cell types as those labeled using Twist2-Cre and Osterix-Cre fate mapping approaches, which previously had been shown to identify mesenchymal progenitors in vitro. Consistent with this past work, sorted CTGF+ cells displayed an ability to differentiate into osteoblasts, chondrocytes, and adipocytes in vitro and into osteoblast, adipocyte, and stromal cell lineages after transplantation into a parietal bone defect. In vivo examination of CTGF reporter expression in bone tissue sections revealed that it marked cells highly localized to the trabecular bone region and was not expressed in the perichondrium or periosteum. Mesenchymal cells retaining high CTGF reporter expression were adjacent to, but distinct from mature osteoblasts lining bone surfaces and endothelial cells forming the vascular sinuses. Comparison of CTGF and Osterix reporter expression in bone tissue sections indicated an inverse correlation between the strength of CTGF expression and osteoblast maturation. Down-regulation of CTGF reporter expression also occurred during in vitro osteogenic differentiation. Collectively, our studies indicate that CTGF reporter mice selectively identify a subpopulation of bone marrow mesenchymal progenitor cells that reside in the trabecular bone region. Copyright © 2014 Elsevier Inc. All rights reserved.
Connective Tissue Growth Factor Reporter Mice Label a Subpopulation of Mesenchymal Progenitor Cells that Reside in the Trabecular Bone Region

PubMed Central

Wang, Wen; Strecker, Sara; Liu, Yaling; Wang, Liping; Assanah, Fayekah; Smith, Spenser; Maye, Peter

2014-01-01

Few gene markers selectively identify mesenchymal progenitor cells inside the bone marrow. We have investigated a cell population located in the mouse bone marrow labeled by Connective Tissue Growth Factor reporter expression (CTGF-EGFP). Bone marrow flushed from CTGF reporter mice yielded an EGFP+ stromal cell population. Interestingly, the percentage of stromal cells retaining CTGF reporter expression decreased with age in vivo and was half the frequency in females compared to males. In culture, CTGF reporter expression and endogenous CTGF expression marked the same cell types as those labeled using Twist2-Cre and Osterix-Cre fate mapping approaches, which previously has been shown to identify mesenchymal progenitors in vitro. Consistent with this past work, sorted CTGF+ cells displayed an ability to differentiate into osteoblasts, chondrocytes, and adipocytes in vitro and into osteoblast, adipocyte, and stromal cell lineages after transplantation into a parietal bone defect. In vivo examination of CTGF reporter expression in bone tissue sections revealed it marked cells highly localized to the trabecular bone region and was not expressed in the perichondrium or periosteum. Mesenchymal cells retaining high CTGF reporter expression were adjacent to, but distinct from mature osteoblasts lining bone surfaces and endothelial cells forming the vascular sinuses. Comparison of CTGF and Osterix reporter expression in bone tissue sections indicated an inverse correlation between the strength of CTGF expression and osteoblast maturation. Down-regulation of CTGF reporter expression also occurred during in vitro osteogenic differentiation. Collectively, our studies indicate that CTGF reporter mice selectively identify a subpopulation of bone marrow mesenchymal progenitor cells that reside in the trabecular bone region. PMID:25464947
Autophagy in Human Embryonic Stem Cells

PubMed Central

Tra, Thien; Gong, Lan; Kao, Lin-Pin; Li, Xue-Lei; Grandela, Catarina; Devenish, Rodney J.; Wolvetang, Ernst; Prescott, Mark

2011-01-01

Autophagy (macroautophagy) is a degradative process that involves the sequestration of cytosolic material including organelles into double membrane vesicles termed autophagosomes for delivery to the lysosome. Autophagy is essential for preimplantation development of mouse embryos and cavitation of embryoid bodies. The precise roles of autophagy during early human embryonic development, remain however largely uncharacterized. Since human embryonic stem cells constitute a unique model system to study early human embryogenesis we investigated the occurrence of autophagy in human embryonic stem cells. We have, using lentiviral transduction, established multiple human embryonic stem cell lines that stably express GFP-LC3, a fluorescent marker for the autophagosome. Each cell line displays both a normal karyotype and pluripotency as indicated by the presence of cell types representative of the three germlayers in derived teratomas. GFP expression and labelling of autophagosomes is retained after differentiation. Baseline levels of autophagy detected in cultured undifferentiated hESC were increased or decreased in the presence of rapamycin and wortmannin, respectively. Interestingly, autophagy was upregulated in hESCs induced to undergo differentiation by treatment with type I TGF-beta receptor inhibitor SB431542 or removal of MEF secreted maintenance factors. In conclusion we have established hESCs capable of reporting macroautophagy and identify a novel link between autophagy and early differentiation events in hESC. PMID:22110659
Heterologous expression of tyrosinase recapitulates the misprocessing and mistrafficking in oculocutaneous albinism type 2: effects of altering intracellular pH and pink-eyed dilution gene expression.

PubMed

Ni-Komatsu, Li; Orlow, Seth J

2006-03-01

The processing and trafficking of tyrosinase, a melanosomal protein essential for pigmentation, was investigated in a human epithelial 293 cell line that stably expresses the protein. The effects of the pink-eyed dilution (p) gene product, in which mutations result in oculocutaneous albinism type 2 (OCA2), on the processing and trafficking of tyrosinase in this cell line were studied. The majority of tyrosinase was retained in the endoplasmic reticulum-Golgi intermediate compartment and the early Golgi compartment in the 293 cells expressing the protein. Coexpression of p could partially correct the mistrafficking of tyrosinase in 293 cells. Tyrosinase was targeted to the late endosomal and lysosomal compartments after treatment of the cells with compounds that correct the tyrosinase mistrafficking in albino melanocytes, most likely through altering intracellular pH, while the substrate tyrosine had no effect on the processing of tyrosinase. Remarkably, this heterologous expression system recapitulates the defective processing and mistrafficking of tyrosinase observed in OCA2 albino melanocytes and certain amelanotic melanoma cells. Coexpression of other melanosomal proteins in this heterologous system may further aid our understanding of the details of normal and pathologic processing of melanosomal proteins.
40 CFR 98.437 - Records that must be retained.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Contained in Pre-Charged Equipment or Closed-Cell Foams § 98.437 Records that must be retained. (a) In... closed-cell foams must retain the following records substantiating each of the imports that they report... entry form. (4) Ports of entry through which the pre-charged equipment or closed-cell foams passed. (5...
40 CFR 98.437 - Records that must be retained.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Contained in Pre-Charged Equipment or Closed-Cell Foams § 98.437 Records that must be retained. (a) In... closed-cell foams must retain the following records substantiating each of the imports that they report... entry form. (4) Ports of entry through which the pre-charged equipment or closed-cell foams passed. (5...
40 CFR 98.437 - Records that must be retained.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Contained in Pre-Charged Equipment or Closed-Cell Foams § 98.437 Records that must be retained. (a) In... closed-cell foams must retain the following records substantiating each of the imports that they report... entry form. (4) Ports of entry through which the pre-charged equipment or closed-cell foams passed. (5...
Germ-line mutations of the p53 tumor suppressor gene in patients with high risk for cancer inactivate the p53 protein.

PubMed Central

Frebourg, T; Kassel, J; Lam, K T; Gryka, M A; Barbier, N; Andersen, T I; Børresen, A L; Friend, S H

1992-01-01

Germ-line mutations in the p53 tumor suppressor gene have been observed in patients with Li-Fraumeni syndrome, brain tumors, second malignancies, and breast cancers. It is unclear whether all of these mutations have inactivated p53 and thereby provide an increased risk for cancer. Therefore, it is necessary to establish the biological significance of these germ-line mutations by the functional and structural analysis of the resulting mutant p53 proteins. We analyzed the ability of seven germ-line mutant proteins observed in patients with Li-Fraumeni syndrome, second primary neoplasms, or familial breast cancer to block the growth of malignant cells and compared the structural properties of the mutant proteins to that of the wild-type protein. Six of seven missense mutations disrupted the growth inhibitory properties and structure of the wild-type protein. One germ-line mutation retained the features of the wild-type p53. Genetic analysis of the breast cancer family in which this mutation was observed indicated that this germ-line mutation was not associated with the development of cancer. These results demonstrate that germ-line p53 mutations observed in patients with Li-Fraumeni syndrome and with second malignancies have inactivated the p53 tumor suppressor gene. The inability of the germ-line p53 mutants to block the growth of malignant cells can explain why patients with these germ-line mutations have an increased risk for cancer. The observation of a functionally silent germ-line mutation indicates that, before associating a germ-line tumor suppressor gene mutation with cancer risk, it is prudent to consider its functional significance. Images PMID:1631137
Germ-line mutations of the p53 tumor suppressor gene in patients with high risk for cancer inactivate the p53 protein.

PubMed

Frebourg, T; Kassel, J; Lam, K T; Gryka, M A; Barbier, N; Andersen, T I; Børresen, A L; Friend, S H

1992-07-15

Germ-line mutations in the p53 tumor suppressor gene have been observed in patients with Li-Fraumeni syndrome, brain tumors, second malignancies, and breast cancers. It is unclear whether all of these mutations have inactivated p53 and thereby provide an increased risk for cancer. Therefore, it is necessary to establish the biological significance of these germ-line mutations by the functional and structural analysis of the resulting mutant p53 proteins. We analyzed the ability of seven germ-line mutant proteins observed in patients with Li-Fraumeni syndrome, second primary neoplasms, or familial breast cancer to block the growth of malignant cells and compared the structural properties of the mutant proteins to that of the wild-type protein. Six of seven missense mutations disrupted the growth inhibitory properties and structure of the wild-type protein. One germ-line mutation retained the features of the wild-type p53. Genetic analysis of the breast cancer family in which this mutation was observed indicated that this germ-line mutation was not associated with the development of cancer. These results demonstrate that germ-line p53 mutations observed in patients with Li-Fraumeni syndrome and with second malignancies have inactivated the p53 tumor suppressor gene. The inability of the germ-line p53 mutants to block the growth of malignant cells can explain why patients with these germ-line mutations have an increased risk for cancer. The observation of a functionally silent germ-line mutation indicates that, before associating a germ-line tumor suppressor gene mutation with cancer risk, it is prudent to consider its functional significance.
Comparison of the X-radiation, drug and ultraviolet-radiation responses of clones isolated from a human colorectal tumor cell line.

PubMed

Qutob, Sami S; Multani, Asha S; Pathak, S; Feng, Y; Kendal, Wayne S; Ng, Cheng E

2004-03-01

We isolated several clones with a wide range of responses to X radiation from an unirradiated human colorectal (HCT 116) tumor cell line. The responses of one of these clones (HCT116-Clone10) and nine other clones to either fractionated or acute (i.e. single, nonfractionated doses) X irradiation in vitro was similar to that of the parental cell line. By contrast, after the same types of treatment, another clone (HCT116-Clone2) manifested a significantly increased survival whereas a third clone (HCT116-CloneK) manifested a significantly decreased survival relative to the parental cell line. This suggested that they were, respectively, a radioresistant and a radiosensitive clone. All three clones (clones 2, 10, K) retained their tumorigenic phenotype and formed tumors in nude mice. G-banding studies demonstrated that they were of human origin and were derived from the same parental cell line. The metaphases of HCT116-Clone2 demonstrated features commonly associated with genomic instability (i.e. mitotic catastrophe including chromosome and chromatid breaks, dicentrics and additional nonclonal markers). Data obtained by quantitative fluorescence in situ hybridization (Q- FISH) analysis failed to demonstrate any apparent correlation between the radiosensitivity and the relative telomere content of these three clones. Interestingly, HCT116-CloneK was the most resistant to several chemotherapeutic drugs (topotecan, camptothecin, etoposide and cisplatin) with diverse mechanisms of action. Also, there were no significant differences in the survivals of the three clones after treatment with UV radiation. Because of the lack of overlap among the relative sensitivities of these clones to X radiation, chemotherapeutic drugs and UV radiation, these clones may be useful models for evaluating the genetic basis of the response of human tumor cells to these treatment agents both in vitro and in vivo.
Evaluation of the effects of a plasma activated medium on cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohades, S.; Laroussi, M., E-mail: mlarouss@odu.edu; Sears, J.

2015-12-15

The interaction of low temperature plasma with liquids is a relevant topic of study to the field of plasma medicine. This is because cells and tissues are normally surrounded or covered by biological fluids. Therefore, the chemistry induced by the plasma in the aqueous state becomes crucial and usually dictates the biological outcomes. This process became even more important after the discovery that plasma activated media can be useful in killing various cancer cell lines. Here, we report on the measurements of concentrations of hydrogen peroxide, a species known to have strong biological effects, produced by application of plasma tomore » a minimum essential culture medium. The activated medium is then used to treat SCaBER cancer cells. Results indicate that the plasma activated medium can kill the cancer cells in a dose dependent manner, retain its killing effect for several hours, and is as effective as apoptosis inducing drugs.« less
Differential Expression of HERV-K (HML-2) Proviruses in Cells and Virions of the Teratocarcinoma Cell Line Tera-1

PubMed Central

Bhardwaj, Neeru; Montesion, Meagan; Roy, Farrah; Coffin, John M.

2015-01-01

Human endogenous retrovirus (HERV-K (HML-2)) proviruses are among the few endogenous retroviral elements in the human genome that retain coding sequence. HML-2 expression has been widely associated with human disease states, including different types of cancers as well as with HIV-1 infection. Understanding of the potential impact of this expression requires that it be annotated at the proviral level. Here, we utilized the high throughput capabilities of next-generation sequencing to profile HML-2 expression at the level of individual proviruses and secreted virions in the teratocarcinoma cell line Tera-1. We identified well-defined expression patterns, with transcripts emanating primarily from two proviruses located on chromosome 22, only one of which was efficiently packaged. Interestingly, there was a preference for transcripts of recently integrated proviruses, over those from other highly expressed but older elements, to be packaged into virions. We also assessed the promoter competence of the 5’ long terminal repeats (LTRs) of expressed proviruses via a luciferase assay following transfection of Tera-1 cells. Consistent with the RNASeq results, we found that the activity of most LTRs corresponded to their transcript levels. PMID:25746218
Directed evolution of human T cell receptor CDR2 residues by phage display dramatically enhances affinity for cognate peptide-MHC without increasing apparent cross-reactivity

PubMed Central

Dunn, Steven M.; Rizkallah, Pierre J.; Baston, Emma; Mahon, Tara; Cameron, Brian; Moysey, Ruth; Gao, Feng; Sami, Malkit; Boulter, Jonathan; Li, Yi; Jakobsen, Bent K.

2006-01-01

The mammalian α/β T cell receptor (TCR) repertoire plays a pivotal role in adaptive immunity by recognizing short, processed, peptide antigens bound in the context of a highly diverse family of cell-surface major histocompatibility complexes (pMHCs). Despite the extensive TCR–MHC interaction surface, peptide-independent cross-reactivity of native TCRs is generally avoided through cell-mediated selection of molecules with low inherent affinity for MHC. Here we show that, contrary to expectations, the germ line-encoded complementarity determining regions (CDRs) of human TCRs, namely the CDR2s, which appear to contact only the MHC surface and not the bound peptide, can be engineered to yield soluble low nanomolar affinity ligands that retain a surprisingly high degree of specificity for the cognate pMHC target. Structural investigation of one such CDR2 mutant implicates shape complementarity of the mutant CDR2 contact interfaces as being a key determinant of the increased affinity. Our results suggest that manipulation of germ line CDR2 loops may provide a useful route to the production of high-affinity TCRs with therapeutic and diagnostic potential. PMID:16600963
Process development for a recombinant Chinese hamster ovary (CHO) cell line utilizing a metal induced and amplified metallothionein expression system.

PubMed

Huang, Edwin P; Marquis, Christopher P; Gray, Peter P

2004-11-20

The suspension Chinese Hamster Ovary cell line, 13-10-302, utilizing the metallothionein (MT) expression system producing recombinant human growth hormone (hGH) was studied in a serum-free and cadmium-free medium at different fermentation scales and modes of operation. Initial experiments were carried out to optimize the concentration of metal addition to induce the MT promoter. Subsequently, the cultivation of the 13-10-302 cell line was scaled up from spinner flasks into bioreactors, and the cultivation duration was extended with fed-batch and perfusion strategies utilizing 180 microM zinc to induce the promoter controlling expression of recombinant hGH. It was shown that a fed-batch process could increase the maximum cell numbers twofold, from 3.3 to 6.3 x 10(6) cell/mL, over those obtained in normal batch fermentations, and this coupled with extended fermentation times resulted in a fourfold increase in final hGH titer, from 135 +/- 15 to 670 +/- 70 mg/L at a specific productivity q(hGH) value of 12 pg cell(-1)d(-1). The addition of sodium butyrate increased the specific productivity of hGH in cells to a value of approximately 48 pg cell(-1)d(-1), resulting in a final hGH titer of over a gram per liter during fed-batch runs. A BioSep acoustic cell recycler was used to retain the cells in the bioreactor during perfusion operation. It was necessary to maintain the specific feeding rates (SFR) above a value of 0.2 vvd/(10(6) cell/mL) to maintain the viability and productivity of the 13-10-302 cells; under these conditions the viable cell number increased to over 10(7) cell/mL and resulted in a volumetric productivity of over 120 mg(hGH) L(-1)d(-1). Process development described in this work demonstrates cultivation at various scales and sustained high levels of productivity under cadmium free condition in a CHO cell line utilizing an inducible metallothionein expression system. (c) 2004 Wiley Periodicals, Inc

Electrical Transmission Line Diametrical Retention Mechanism

DOEpatents

Hall, David R.; Hall, Jr., H. Tracy; Pixton, David; Dahlgren, Scott; Sneddon, Cameron; Briscoe, Michael; Fox, Joe

2006-01-03

The invention is a mechanism for retaining an electrical transmission line. In one embodiment of the invention it is a system for retaining an electrical transmission line within downhole components. The invention allows a transmission line to be attached to the internal diameter of drilling components that have a substantially uniform drilling diameter. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string, drill collars, heavy weight drill pipe, and jars. The system also includes a coaxial cable running between the first and second end of a drill pipe, the coaxial cable having a conductive tube and a conductive core within it. The invention allows the electrical transmission line to withstand the tension and compression of drill pipe during routine drilling cycles.
Identification of distinct topographical surface microstructures favoring either undifferentiated expansion or differentiation of murine embryonic stem cells.

PubMed

Markert, Lotte D'Andrea; Lovmand, Jette; Foss, Morten; Lauridsen, Rune Hoff; Lovmand, Michael; Füchtbauer, Ernst-Martin; Füchtbauer, Annette; Wertz, Karin; Besenbacher, Flemming; Pedersen, Finn Skou; Duch, Mogens

2009-11-01

The potential of embryonic stem (ES) cells for both self-renewal and differentiation into cells of all three germ layers has generated immense interest in utilizing these cells for tissue engineering or cell-based therapies. However, the ability to culture undifferentiated ES cells without the use of feeder cells as well as means to obtain homogeneous, differentiated cell populations devoid of residual pluripotent ES cells still remain major challenges. Here we have applied murine ES cells to topographically microstructured surface libraries, BioSurface Structure Arrays (BSSA), and investigated whether these could be used to (i) identify topographically microstructured growth supports alleviating the need for feeder cells for expansion of undifferentiated ES cells and (ii) identify specific types of microstructures enforcing differentiation of ES cells. The BSSA surfaces arrays consisted of 504 different topographical microstructures each located in a tester field of 3 x 3 mm. The murine ES cell lines CJ7 and KH2 were seeded upon the BSSA libraries and specific topographical structures facilitating either undifferentiated ES cell growth or enhancing spreading indicative of differentiation of the ES cells were identified. Secondly serial passage of undifferentiated CJ7 ES cells on selected microstructures, identified in the screening of these BSSA libraries, showed that these cells had retained germ-line potential. These results indicate that one specific type of topographical surface microstructures, identified by the BSSA technology, can substitute for feeder cells and that another subset may be used to eliminate undifferentiated ES cells from a population of differentiated ES cells.
Production, characterisation, and cytocompatibility of porous titanium-based particulate scaffolds.

PubMed

Luthringer, B J C; Ali, F; Akaichi, H; Feyerabend, F; Ebel, T; Willumeit, R

2013-10-01

Despite its non-matching mechanical properties titanium remains the preferred metal implant material in orthopaedics. As a consequence in some cases stress shielding effect occurs, leading to implant loosening, osteopenia, and finally revision surgery. Porous metal scaffolds to allow easier specialised cells ingrowth with mechanical properties closer to the ones of bone can overcome this problem. This should improve healing processes, implant integration, and dynamic strength of implants retaining. Three Ti-6Al-4V materials were metal injection moulded and tailored porosities were effectively achieved. After microstructural and mechanical characterisation, two different primary cells of mesenchymal origin (human umbilical cord perivascular cells and human bone derived cells which revealed to be two pertinent models) as well as one cell line originated from primary osteogenic sarcoma, Saos-2, were bestowed to investigate cell-material interaction on genomic and proteome levels. Biological examinations disclosed that no material has negative impact on early adhesion, proliferation or cell viability. An efficient cell ingrowth into material with an average porosity of 25-50 μm was proved.
The mitochondrial uncoupling protein-2 promotes chemoresistance in cancer cells

PubMed Central

Derdak, Zoltan; Mark, Nicholas M.; Beldi, Guido; Robson, Simon C.; Wands, Jack R.; Baffy, György

2008-01-01

Cancer cells acquire drug resistance as a result of selection pressure dictated by unfavorable microenvironments. This survival process is facilitated through efficient control of oxidative stress originating from mitochondria that typically initiates programmed cell death. We show this critical adaptive response in cancer cells to be linked to uncoupling protein-2 (UCP2), a mitochondrial suppressor of reactive oxygen species (ROS). UCP2 is present in drug-resistant lines of various cancer cells and in human colon cancer. Overexpression of UCP2 in HCT116 human colon cancer cells inhibits ROS accumulation and apoptosis post-exposure to chemotherapeutic agents. Tumor xenografts of UCP2-overexpressing HCT116 cells retain growth in nude mice receiving chemotherapy. Augmented cancer cell survival is accompanied by altered N-terminal phosphorylation of the pivotal tumor suppressor p53 and induction of the glycolytic phenotype (Warburg effect). These findings link UCP2 with molecular mechanisms of chemoresistance. Targeting UCP2 may be considered a novel treatment strategy for cancer. PMID:18413749
Spin filter perfusion system for high density cell culture: production of recombinant urinary type plasminogen activator in CHO cells.

PubMed

Avgerinos, G C; Drapeau, D; Socolow, J S; Mao, J I; Hsiao, K; Broeze, R J

1990-01-01

We have used a 20 liter stirred tank fermentor, equipped with a 127 mesh ethylene-tetrafluoroethylene rotating screen for cell recycle, for the continuous production of recombinant single chain urokinase-type plasminogen activator (rscu-PA) from Chinese hamster ovary (CHO) cells. Viable cell densities between 60 and 74 million per ml were maintained at medium perfusion rates of 3.0 to 4.0 fermentor volumes per day. Cells were retained by the 120 micron nominal opening filter through the formation of "clumped" cell aggregates of 200 to 600 microns in size, which did not foul the filter. In 31 days of culture, a total of 51 grams of rscu-PA were produced in 1,000 liters of medium. The rscu-PA produced over the course of this continuous culture was purified and characterized both in vitro and in vivo and shown to be comparable to natural scu-PA produced from the transformed human kidney cell line, TCL-598.
Novel revertants of H-ras oncogene-transformed R6-PKC3 cells.

PubMed Central

Krauss, R S; Guadagno, S N; Weinstein, I B

1992-01-01

Rat 6 fibroblasts that overproduce protein kinase C beta 1 (R6-PKC3 cells) are hypersensitive to complete transformation by the T24 H-ras oncogene; yet T24 H-ras-transformed R6-PKC3 cells are killed when exposed to 12-O-tetradecanoylphorbol-13-acetate (TPA) (W.-L. W. Hsiao, G. M. Housey, M. D. Johnson, and I. B. Weinstein, Mol. Cell. Biol. 9:2641-2647, 1989). Treatment of an R6-PKC3 subclone that harbors a T24 H-ras gene under the control of an inducible mouse metallothionein I promoter with ZnSO4 and TPA is extremely cytocidal. This procedure was used to isolate rare revertants that are resistant to this toxicity. Two revertant lines, R-1a and ER-1-2, continue to express very high levels of protein kinase C enzyme activity but, unlike the parental cells, do not grow in soft agar. Furthermore, these revertants are resistant to the induction of anchorage-independent growth by the v-src, v-H-ras, v-raf, and, in the case of the R-1a line, v-fos oncogenes. Both revertant lines, however, retain the ability to undergo morphological alterations when either treated with TPA or infected with a v-H-ras virus, thus dissociating anchorage independence from morphological transformation. The revertant phenotype of both R-1a and ER-1-2 cells is dominant over the transformed phenotype in somatic cell hybridizations. Interestingly, the revertant lines no longer induce the metallothionein I-T24 H-ras construct or the endogenous metallothionein I and II genes in response to three distinct agents: ZnSO4, TPA, and dexamethasone. The reduction in activity of metallothionein promoters seen in these revertants may reflect defects in signal transduction pathways that control the expression of genes mediating specific effects of protein kinase C and certain oncogenes in cell transformation. Images PMID:1535685
Antimicrobial Action and Cell Agglutination by the Eosinophil Cationic Protein Are Modulated by the Cell Wall Lipopolysaccharide Structure

PubMed Central

Pulido, David; Moussaoui, Mohammed; Andreu, David; Nogués, M. Victòria

2012-01-01

Antimicrobial proteins and peptides (AMPs) are essential effectors of innate immunity, acting as a first line of defense against bacterial infections. Many AMPs exhibit high affinity for cell wall structures such as lipopolysaccharide (LPS), a potent endotoxin able to induce sepsis. Hence, understanding how AMPs can interact with and neutralize LPS endotoxin is of special relevance for human health. Eosinophil cationic protein (ECP) is an eosinophil secreted protein with high activity against both Gram-negative and Gram-positive bacteria. ECP has a remarkable affinity for LPS and a distinctive agglutinating activity. By using a battery of LPS-truncated E. coli mutant strains, we demonstrate that the polysaccharide moiety of LPS is essential for ECP-mediated bacterial agglutination, thereby modulating its antimicrobial action. The mechanism of action of ECP at the bacterial surface is drastically affected by the LPS structure and in particular by its polysaccharide moiety. We have also analyzed an N-terminal fragment that retains the whole protein activity and displays similar cell agglutination behavior. Conversely, a fragment with further minimization of the antimicrobial domain, though retaining the antimicrobial capacity, significantly loses its agglutinating activity, exhibiting a different mechanism of action which is not dependent on the LPS composition. The results highlight the correlation between the protein's antimicrobial activity and its ability to interact with the LPS outer layer and promote bacterial agglutination. PMID:22330910
Antimicrobial action and cell agglutination by the eosinophil cationic protein are modulated by the cell wall lipopolysaccharide structure.

PubMed

Pulido, David; Moussaoui, Mohammed; Andreu, David; Nogués, M Victòria; Torrent, Marc; Boix, Ester

2012-05-01

Antimicrobial proteins and peptides (AMPs) are essential effectors of innate immunity, acting as a first line of defense against bacterial infections. Many AMPs exhibit high affinity for cell wall structures such as lipopolysaccharide (LPS), a potent endotoxin able to induce sepsis. Hence, understanding how AMPs can interact with and neutralize LPS endotoxin is of special relevance for human health. Eosinophil cationic protein (ECP) is an eosinophil secreted protein with high activity against both Gram-negative and Gram-positive bacteria. ECP has a remarkable affinity for LPS and a distinctive agglutinating activity. By using a battery of LPS-truncated E. coli mutant strains, we demonstrate that the polysaccharide moiety of LPS is essential for ECP-mediated bacterial agglutination, thereby modulating its antimicrobial action. The mechanism of action of ECP at the bacterial surface is drastically affected by the LPS structure and in particular by its polysaccharide moiety. We have also analyzed an N-terminal fragment that retains the whole protein activity and displays similar cell agglutination behavior. Conversely, a fragment with further minimization of the antimicrobial domain, though retaining the antimicrobial capacity, significantly loses its agglutinating activity, exhibiting a different mechanism of action which is not dependent on the LPS composition. The results highlight the correlation between the protein's antimicrobial activity and its ability to interact with the LPS outer layer and promote bacterial agglutination.
Accurate determination of fiber water-retaining capability at process conditions by headspace gas chromatography.

PubMed

Zhang, Shu-Xin; Chai, Xin-Sheng; He, Liang

2016-09-16

This work reports on a method for the accurate determination of fiber water-retaining capability at process conditions by headspace gas chromatography (HS-GC) method. The method was based the HS-GC measurement of water vapor on a set closed vials containing in a given amount pulp with different amounts of water addition, from under-saturation to over-saturation. By plotting the equilibrated water vapor signal vs. the amount of water added in pulp, two different trend lines can be observed, in which the transition of the lines corresponds to fiber water-retaining capability. The results showed that the HS-GC method has good measurement precision (much better than the reference method) and good accuracy. The present method can be also used for determining pulp fiber water-retaining capability at the process temperatures in both laboratory research and mill applications. Copyright © 2016 Elsevier B.V. All rights reserved.
Endocrine-Therapy-Resistant ESR1 Variants Revealed by Genomic Characterization of Breast-Cancer-Derived Xenografts

PubMed Central

Li, Shunqiang; Shen, Dong; Shao, Jieya; Crowder, Robert; Liu, Wenbin; Prat, Aleix; He, Xiaping; Liu, Shuying; Hoog, Jeremy; Lu, Charles; Ding, Li; Griffith, Obi L.; Miller, Christopher; Larson, Dave; Fulton, Robert S.; Harrison, Michelle; Mooney, Tom; McMichael, Joshua F.; Luo, Jingqin; Tao, Yu; Goncalves, Rodrigo; Schlosberg, Christopher; Hiken, Jeffrey F.; Saied, Laila; Sanchez, Cesar; Giuntoli, Therese; Bumb, Caroline; Cooper, Crystal; Kitchens, Robert T.; Lin, Austin; Phommaly, Chanpheng; Davies, Sherri R.; Zhang, Jin; Kavuri, Megha Shyam; McEachern, Donna; Dong, Yi Yu; Ma, Cynthia; Pluard, Timothy; Naughton, Michael; Bose, Ron; Suresh, Rama; McDowell, Reida; Michel, Loren; Aft, Rebecca; Gillanders, William; DeSchryver, Katherine; Wilson, Richard K.; Wang, Shaomeng; Mills, Gordon B.; Gonzalez-Angulo, Ana; Edwards, John R.; Maher, Christopher; Perou, Charles M.; Mardis, Elaine R.; Ellis, Matthew J.

2013-01-01

SUMMARY To characterize patient-derived xenografts (PDXs) for functional studies, we made whole-genome comparisons with originating breast cancers representative of the major intrinsic subtypes. Structural and copy number aberrations were found to be retained with high fidelity. However, at the single-nucleotide level, variable numbers of PDX-specific somatic events were documented, although they were only rarely functionally significant. Variant allele frequencies were often preserved in the PDXs, demonstrating that clonal representation can be transplantable. Estrogen-receptor-positive PDXs were associated with ESR1 ligand-binding-domain mutations, gene amplification, or an ESR1/YAP1 translocation. These events produced different endocrine-therapy-response phenotypes in human, cell line, and PDX endocrine-response studies. Hence, deeply sequenced PDX models are an important resource for the search for genome-forward treatment options and capture endocrine-drug-resistance etiologies that are not observed in standard cell lines. The originating tumor genome provides a benchmark for assessing genetic drift and clonal representation after transplantation. PMID:24055055
Removing celiac disease-related gluten proteins from bread wheat while retaining technological properties: a study with Chinese Spring deletion lines

PubMed Central

van den Broeck, Hetty C; van Herpen, Teun WJM; Schuit, Cees; Salentijn, Elma MJ; Dekking, Liesbeth; Bosch, Dirk; Hamer, Rob J; Smulders, Marinus JM; Gilissen, Ludovicus JWJ; van der Meer, Ingrid M

2009-01-01

Background Gluten proteins can induce celiac disease (CD) in genetically susceptible individuals. In CD patients gluten-derived peptides are presented to the immune system, which leads to a CD4+ T-cell mediated immune response and inflammation of the small intestine. However, not all gluten proteins contain T-cell stimulatory epitopes. Gluten proteins are encoded by multigene loci present on chromosomes 1 and 6 of the three different genomes of hexaploid bread wheat (Triticum aestivum) (AABBDD). Results The effects of deleting individual gluten loci on both the level of T-cell stimulatory epitopes in the gluten proteome and the technological properties of the flour were analyzed using a set of deletion lines of Triticum aestivum cv. Chinese Spring. The reduction of T-cell stimulatory epitopes was analyzed using monoclonal antibodies that recognize T-cell epitopes present in gluten proteins. The deletion lines were technologically tested with respect to dough mixing properties and dough rheology. The results show that removing the α-gliadin locus from the short arm of chromosome 6 of the D-genome (6DS) resulted in a significant decrease in the presence of T-cell stimulatory epitopes but also in a significant loss of technological properties. However, removing the ω-gliadin, γ-gliadin, and LMW-GS loci from the short arm of chromosome 1 of the D-genome (1DS) removed T-cell stimulatory epitopes from the proteome while maintaining technological properties. Conclusion The consequences of these data are discussed with regard to reducing the load of T-cell stimulatory epitopes in wheat, and to contributing to the design of CD-safe wheat varieties. PMID:19351412
Cellular internalization of LiNbO3 nanocrystals for second harmonic imaging and the effects on stem cell differentiation

NASA Astrophysics Data System (ADS)

Li, Jianhua; Qiu, Jichuan; Guo, Weibo; Wang, Shu; Ma, Baojin; Mou, Xiaoning; Tanes, Michael; Jiang, Huaidong; Liu, Hong

2016-03-01

Second harmonic generation (SHG) nanocrystals have recently been reported to label cancer cells and other functional cell lines due to their unique double-frequency property. In this paper, we report for the first time the use of lithium niobate (LiNbO3, LN) nanocrystals as SHG labels for imaging stem cells. Rat mesenchymal stem cells (rMSCs) were labeled with LN nanocrystals in order to study the cellular internalization of the nanocrystals and the influence on stem cell differentiation. The results showed that LN nanocrystals were endocytosed by the rMSCs and the distribution of the internalized nanoparticles demonstrated a high consistency with the orientation of the actin filaments. Besides, LN-labeled rMSCs showed a concentration-dependent viability. Most importantly, rMSCs labeled with 50 μg per mL of LN nanocrystals retained their ability to differentiate into both osteogenic and adipogenic lineages. The results prove that LN nanocrystals can be used as a cytocompatible, near-infrared (NIR) light driven cell label for long-term imaging, without hindering stem cell differentiation. This work will promote the use of LN nanocrystals to broader applications like deep-tissue tracking, remote drug delivery and stem cell therapy.Second harmonic generation (SHG) nanocrystals have recently been reported to label cancer cells and other functional cell lines due to their unique double-frequency property. In this paper, we report for the first time the use of lithium niobate (LiNbO3, LN) nanocrystals as SHG labels for imaging stem cells. Rat mesenchymal stem cells (rMSCs) were labeled with LN nanocrystals in order to study the cellular internalization of the nanocrystals and the influence on stem cell differentiation. The results showed that LN nanocrystals were endocytosed by the rMSCs and the distribution of the internalized nanoparticles demonstrated a high consistency with the orientation of the actin filaments. Besides, LN-labeled rMSCs showed a concentration-dependent viability. Most importantly, rMSCs labeled with 50 μg per mL of LN nanocrystals retained their ability to differentiate into both osteogenic and adipogenic lineages. The results prove that LN nanocrystals can be used as a cytocompatible, near-infrared (NIR) light driven cell label for long-term imaging, without hindering stem cell differentiation. This work will promote the use of LN nanocrystals to broader applications like deep-tissue tracking, remote drug delivery and stem cell therapy. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00785f
Rewiring the taste system.

PubMed

Lee, Hojoon; Macpherson, Lindsey J; Parada, Camilo A; Zuker, Charles S; Ryba, Nicholas J P

2017-08-17

In mammals, taste buds typically contain 50-100 tightly packed taste-receptor cells (TRCs), representing all five basic qualities: sweet, sour, bitter, salty and umami. Notably, mature taste cells have life spans of only 5-20 days and, consequently, are constantly replenished by differentiation of taste stem cells. Given the importance of establishing and maintaining appropriate connectivity between TRCs and their partner ganglion neurons (that is, ensuring that a labelled line from sweet TRCs connects to sweet neurons, bitter TRCs to bitter neurons, sour to sour, and so on), we examined how new connections are specified to retain fidelity of signal transmission. Here we show that bitter and sweet TRCs provide instructive signals to bitter and sweet target neurons via different guidance molecules (SEMA3A and SEMA7A). We demonstrate that targeted expression of SEMA3A or SEMA7A in different classes of TRCs produces peripheral taste systems with miswired sweet or bitter cells. Indeed, we engineered mice with bitter neurons that now responded to sweet tastants, sweet neurons that responded to bitter or sweet neurons responding to sour stimuli. Together, these results uncover the basic logic of the wiring of the taste system at the periphery, and illustrate how a labelled-line sensory circuit preserves signalling integrity despite rapid and stochastic turnover of receptor cells.
Rewiring the Taste System

PubMed Central

Lee, Hojoon; Macpherson, Lindsey J.; Parada, Camilo A.; Zuker, Charles S.; Ryba, Nicholas J.P.

2018-01-01

In mammals, taste buds typically contain 50-100 tightly packed taste receptor cells (TRCs) representing all five basic qualities: sweet, sour, bitter, salty and umami1,2. Notably, mature taste cells have life spans of only 5-20 days, and consequently, are constantly replenished by differentiation of taste stem cells3. Given the importance of establishing and maintaining appropriate connectivity between TRCs and their partner ganglion neurons (i.e. ensuring that a labeled line from sweet TRCs connects to sweet neurons, bitter TRCs to bitter neurons, sour to sour, etc.), we examined how new connections are specified to retain fidelity of signal transmission. Our results show that bitter and sweet TRCs provide instructive signals to bitter and sweet target neurons via different guidance molecules (Sema3A and Sema7A)4-6. Here, we demonstrate that targeted expression of Sema3A or Sema7A in different classes of TRCs produce peripheral taste systems with miswired sweet or bitter cells. Indeed, we engineered animals whereby bitter neurons now respond to sweet tastants, sweet neurons respond to bitter, or with sweet neurons responding to sour stimuli. Together, these results uncover the basic logic of the wiring of the taste system at the periphery, and illustrate how a labeled-line sensory circuit preserves signaling integrity despite rapid and stochastic turnover of receptor cells. PMID:28792937
Human neural progenitor cells retain viability, phenotype, proliferation, and lineage differentiation when labeled with a novel iron oxide nanoparticle, Molday ION Rhodamine B

PubMed Central

Shen, Wei-Bin; Plachez, Celine; Chan, Amanda; Yarnell, Deborah; Puche, Adam C; Fishman, Paul S; Yarowsky, Paul

2013-01-01

Ultrasmall superparamagnetic iron-oxide particles (USPIOs) loaded into stem cells have been suggested as a way to track stem cell transplantation with magnetic resonance imaging, but the labeling, and post-labeling proliferation, viability, differentiation, and retention of USPIOs within the stem cells have yet to be determined for each type of stem cell and for each type of USPIO. Molday ION Rhodamine B™ (BioPAL, Worcester, MA, USA) (MIRB) has been shown to be a USPIO labeling agent for mesenchymal stem cells, glial progenitor cells, and stem cell lines. In this study, we have evaluated MIRB labeling in human neuroprogenitor cells and found that human neuroprogenitor cells are effectively labeled with MIRB without use of transfection reagents. Viability, proliferation, and differentiation properties are unchanged between MIRB-labeled neuroprogenitors cells and unlabeled cells. Moreover, MIRB-labeled human neuroprogenitor cells can be frozen, thawed, and replated without loss of MIRB or even without loss of their intrinsic biology. Overall, those results show that MIRB has advantageous properties that can be used for cell-based therapy. PMID:24348036
Overexpression of LLT1 (OCIL, CLEC2D) on prostate cancer cells inhibits NK cell-mediated killing through LLT1-NKRP1A (CD161) interaction.

PubMed

Mathew, Stephen O; Chaudhary, Pankaj; Powers, Sheila B; Vishwanatha, Jamboor K; Mathew, Porunelloor A

2016-10-18

Prostate cancer is the most common type of cancer diagnosed and the second leading cause of cancer-related death in American men. Natural Killer (NK) cells are the first line of defense against cancer and infections. NK cell function is regulated by a delicate balance between signals received through activating and inhibitory receptors. Previously, we identified Lectin-like transcript-1 (LLT1/OCIL/CLEC2D) as a counter-receptor for the NK cell inhibitory receptor NKRP1A (CD161). Interaction of LLT1 expressed on target cells with NKRP1A inhibits NK cell activation. In this study, we have found that LLT1 was overexpressed on prostate cancer cell lines (DU145, LNCaP, 22Rv1 and PC3) and in primary prostate cancer tissues both at the mRNA and protein level. We further showed that LLT1 is retained intracellularly in normal prostate cells with minimal cell surface expression. Blocking LLT1 interaction with NKRP1A by anti-LLT1 mAb on prostate cancer cells increased the NK-mediated cytotoxicity of prostate cancer cells. The results indicate that prostate cancer cells may evade immune attack by NK cells by expressing LLT1 to inhibit NK cell-mediated cytolytic activity through LLT1-NKRP1A interaction. Blocking LLT1-NKRP1A interaction will make prostate cancer cells susceptible to killing by NK cells and therefore may be a new therapeutic option for treatment of prostate cancer.
CD30 Receptor-Targeted Lentiviral Vectors for Human Induced Pluripotent Stem Cell-Specific Gene Modification.

PubMed

Friedel, Thorsten; Jung-Klawitter, Sabine; Sebe, Attila; Schenk, Franziska; Modlich, Ute; Ivics, Zoltán; Schumann, Gerald G; Buchholz, Christian J; Schneider, Irene C

2016-05-01

Cultures of induced pluripotent stem cells (iPSCs) often contain cells of varying grades of pluripotency. We present novel lentiviral vectors targeted to the surface receptor CD30 (CD30-LV) to transfer genes into iPSCs that are truly pluripotent as demonstrated by marker gene expression. We demonstrate that CD30 expression is restricted to SSEA4(high) cells of human iPSC cultures and a human embryonic stem cell line. When CD30-LV was added to iPSCs during routine cultivation, efficient and exclusive transduction of cells positive for the pluripotency marker Oct-4 was achieved, while retaining their pluripotency. When added during the reprogramming process, CD30-LV solely transduced cells that became fully reprogrammed iPSCs as confirmed by co-expression of endogenous Nanog and the reporter gene. Thus, CD30-LV may serve as novel tool for the selective gene transfer into PSCs with broad applications in basic and therapeutic research.
Establishment and evaluation of a stable steroidogenic caprine luteal cell line.

PubMed

Li, Wei; Xu, Xingang; Huang, Yong; Li, Zhaocai; Yu, Gaoshui; Wang, Zhisheng; Ding, Li; Tong, Dewen

2012-07-15

Many physiological, biological, pharmacologic, and toxicologic events and compounds affect the function of Saanen dairy goat luteal cells, resulting in implantation failure or early embryonic loss. Although primary luteal cell cultures have been used, their finite lifespan precludes assessment of long-term effects. In the present study, primary caprine luteal cells (CLCs) were immortalized through transfection of a plasmid containing the human telomerase reverse transcriptase (hTERT) gene. The expression of hTERT and telomerase activity were evaluated in transduced CLCs (hTERT-CLCs). In this study, these cells steadily expressed hTERT gene and exhibited higher telomerase activity at Passages 30 and 50. The hTERT-CLCs at Passages 30 and 50 expressed genes encoding key proteins, enzymes and receptors inherent to normal luteal cells, e.g., steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), 3β-hydroxysteroid dehydrogenase (3β-HSD), and LH-receptor (LH-R). In addition, immortalized caprine luteal cells produced detectable quantities of progesterone in response to 8-bromo-cAMP (8-Br-cAMP) or 22(R)-hydroxycholesterol (22R-HC) stimulation. Furthermore, this cell line appeared to proliferate more quickly than control cells, although no neoplastic transformation occurred either in vivo or in vitro. We concluded the immortalized CLCs by hTERT retained their original characteristics and may provide a useful model to study luteal cell functions. Copyright © 2012 Elsevier Inc. All rights reserved.
Teeth in the Line of Fracture: To Retain or Remove?

PubMed Central

Samson, Jimson; John, Reena; Jayakumar, Shalini

2010-01-01

The purpose of this study was to analyze mandibular fracture site, relationship of the fracture line to the periodontium, vitality of teeth, displacement of the fracture segments and their implications, and determine whether to retain or remove the teeth in the fracture line. Fifty patients with 62 fractures were involved in this study. An electric pulp tester was used to measure the pulpal response. The degree of fracture displacement and the relationship of the fracture line to the periodontium were evaluated using panoramic radiographs. Fractures of the parasymphysis region constituted a majority of 60.87% in the gross displacement category. Four of 50 patients showed no response presurgically and minimal response postoperatively on pulp vitality testing. Patients with teeth in the fracture line showing no response on pulp vitality testing should be advised extraction to avoid further complications. PMID:22132255
Transcriptional Differences between Rhesus Embryonic Stem Cells Generated from In Vitro and In Vivo Derived Embryos

PubMed Central

Harvey, Alexandra J.; Mao, Shihong; Lalancette, Claudia; Krawetz, Stephen A.; Brenner, Carol A.

2012-01-01

Numerous studies have focused on the transcriptional signatures that underlie the maintenance of embryonic stem cell (ESC) pluripotency. However, it remains unclear whether ESC retain transcriptional aberrations seen in in vitro cultured embryos. Here we report the first global transcriptional profile comparison between ESC generated from either in vitro cultured or in vivo derived primate embryos by microarray analysis. Genes involved in pluripotency, oxygen regulation and the cell cycle were downregulated in rhesus ESC generated from in vitro cultured embryos (in vitro ESC). Significantly, several gene differences are similarly downregulated in preimplantation embryos cultured in vitro, which have been associated with long term developmental consequences and disease predisposition. This data indicates that prior to derivation, embryo quality may influence the molecular signature of ESC lines, and may differentially impact the physiology of cells prior to or following differentiation. PMID:23028448

Fluorescent Protein-Based Quantification of Alternative Splicing of a Target Cassette Exon in Mammalian Cells.

PubMed

Gurskaya, N G; Staroverov, D B; Lukyanov, K A

2016-01-01

Alternative splicing is an important mechanism of regulation of gene expression and expansion of proteome complexity. Recently we developed a new fluorescence reporter for quantitative analysis of alternative splicing of a target cassette exon in live cells (Gurskaya et al., 2012). It consists of a specially designed minigene encoding red and green fluorescent proteins (Katushka and TagGFP2) and a fragment of the target gene between them. Skipping or inclusion of the alternative exon induces a frameshift; ie, alternative exon length must not be a multiple of 3. Finally, red and green fluorescence intensities of cells expressing this reporter are used to estimate the percentage of alternative (exon-skipped) and normal (exon-retained) transcripts. Here, we provide a detailed description of design and application of the fluorescence reporter of a target alternative exon splicing in mammalian cell lines. © 2016 Elsevier Inc. All rights reserved.
Primordial germ cell biology at the beginning of the XXI century.

PubMed

De Felici, Massimo

2009-01-01

At the XIV Workshop on the Development and Function of the Reproductive Organs held at the Congress Centre of the University of Rome Tor Vergata, Monteporzio Catone, Rome, Italy, the introduction to the first session entitled Mammalian primordial germ cells dedicated to the memory of Anne McLaren, was the occasion for a concise review of the state of art of research on the biology of primordial germ cells (PGCs). This great, unforgettable scientist, who died in a car accident in July 2007, dedicated most of her studies to this field over the last 25 years. Topics briefly reviewed in this Meeting Report are: 1) how the germ line is determined; 2) what are the mechanisms underlying PGC migration; 3) to what extent PGC survival, proliferation and differentiation are cell autonomous or environmentally controlled processes and 4) how the potential for totipotency is retained in PGCs.
INTRAUTERINE FATE OF INVASIVE TROPHOBLAST CELLS1

PubMed Central

Rosario, Gracy X.; Ain, Rupasri; Konno, Toshihiro; Soares, Michael J.

2009-01-01

Invasion of trophoblast cells into the uterine spiral arteries and the uterine wall is characteristic of hemochorial placentation. In the rat, trophoblast cells penetrate through the uterine decidua and well into the metrial gland. In this report, we examined the fate of these invasive trophoblast cells following parturition. Invasive trophoblast endocrine cells were retained in the postpartum mesometrial uterus in the rat. The demise of invasive trophoblast cells was followed by the appearance of differentiated smooth muscle cells surrounding blood vessels previously lined by invasive trophoblast cells and an infiltration of macrophages. Regulation of intrauterine trophoblast cell fate was investigated following premature removal of the fetus or removal of the fetus and chorioallantoic placenta. The presence of the fetus affected the distribution of invasive trophoblast cells within the uterus but did not negatively impact their survival. Premature removal of all chorioallantoic placentas and associated fetuses from a uterus resulted in extensive removal of intrauterine trophoblast cells. In summary, the postpartum demise of intrauterine invasive trophoblast cells is a dynamic developmental event regulated in part by the removal of trophic signals emanating from the chorioallantoic placenta. PMID:19344949
The isolation and characterization of a telomerase immortalized goat trophoblast cell line.

PubMed

Dong, F; Huang, Y; Li, W; Zhao, X; Zhang, W; Du, Q; Zhang, H; Song, X; Tong, D

2013-12-01

Trophoblast cells play vital roles in the processes of embryonic implantation and placentation. Many toxicological compounds can induce the malfunction of trophoblast cells, resulting in implantation failure or early embryonic loss. The finite lifespan of primary trophoblast cells limits investigation of the long-term effects of some toxicological compounds on trophoblast cells in vitro. In this study, primary goat trophoblast cells were purified by density gradient centrifugation and specific immuno-affinity purification. Then, the purified cells were immortalized through transfection of a plasmid containing the human telomerase reverse transcriptase (hTERT) gene. hTERT-transfected goat trophoblast cells (hTERT-GTCs) could steadily express hTERT gene and exhibit higher telomerase activity, and persistently proliferate without any signs of senescence up to 50 passages. The immortalized goat trophoblast cells still possessed the basic and key properties of normal primary goat trophoblast cells to express the specific intracellular marker cytokeratin 7 (CK-7) and secrete chorionic gonadotrophin β-subunit (CG-β) and placental lactogen (PL). Further studies showed that the immortalized goat trophoblast cells expressed vimentin and non-classical MHC class I antigen and exhibited invasive phenotype, suggesting that the immortalized goat trophoblasts resembled human extravillous trophoblasts. In addition, this cell line did not show neoplastic transformation either in vivo or in vitro. We concluded the immortalized goat trophoblast cells by hTERT transfection retained the basic and key characteristics of primary trophoblast cells and may provide a useful model to study the effects of some toxicological compounds on trophoblast cells. Copyright © 2013 Elsevier Ltd. All rights reserved.
Anticancer copper(II) phosphorus dendrimers are potent proapoptotic Bax activators.

PubMed

Mignani, Serge; El Brahmi, Nabil; Eloy, Laure; Poupon, Joel; Nicolas, Valérie; Steinmetz, Anke; El Kazzouli, Said; Bousmina, Mosto M; Blanchard-Desce, Mireille; Caminade, Anne-Marie; Majoral, Jean-Pierre; Cresteil, Thierry

2017-05-26

A multivalent phosphorus dendrimer 1G 3 and its corresponding Cu-complex, 1G 3 -Cu have been recently identified as agents retaining high antiproliferative potency. This antiproliferative capacity was preserved in cell lines overexpressing the efflux pump ABC B1, whereas cross-resistance was observed in ovarian cancer cell lines resistant to cisplatin. Theoretical 3D models were constructed: the dendrimers appear as irregularly shaped disk-like nano-objects of about 22 Å thickness and 49 Å diameter, which accumulated in cells after penetration by endocytosis. To get insight in their mode of action, cell death pathways have been examined in human cancer cell lines: early apoptosis was followed by secondary necrosis after multivalent phosphorus dendrimers exposure. The multivalent plain phosphorus dendrimer 1G 3 moderately activated caspase-3 activity, in contrast with the multivalent Cu-conjugated phosphorus dendrimer 1G 3 -Cu which strikingly reduced the caspase-3 content and activity. This decrease of caspase activity is not related to the presence of copper, since inorganic copper has no or little effect on caspase-3. Conversely the potent apoptosis activation could be related to a noticeable translocation of Bax to the mitochondria, resulting in the release of AIF into the cytosol, its translocation to the nucleus and a severe DNA fragmentation, without alteration of the cell cycle. The multivalent Cu-conjugated phosphorus dendrimer is more efficient than its non-complexed analog to activate this pathway in close relationship with the higher antiproliferative potency. Therefore, this multivalent Cu-conjugated phosphorus dendrimer 1G 3 -Cu can be considered as a new and promising first-in-class antiproliferative agent with a distinctive mode of action, inducing apoptosis tumor cell death through Bax activation pathway. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Human Stem Cell-like Memory T Cells Are Maintained in a State of Dynamic Flux.

PubMed

Ahmed, Raya; Roger, Laureline; Costa Del Amo, Pedro; Miners, Kelly L; Jones, Rhiannon E; Boelen, Lies; Fali, Tinhinane; Elemans, Marjet; Zhang, Yan; Appay, Victor; Baird, Duncan M; Asquith, Becca; Price, David A; Macallan, Derek C; Ladell, Kristin

2016-12-13

Adaptive immunity requires the generation of memory T cells from naive precursors selected in the thymus. The key intermediaries in this process are stem cell-like memory T (T SCM ) cells, multipotent progenitors that can both self-renew and replenish more differentiated subsets of memory T cells. In theory, antigen specificity within the T SCM pool may be imprinted statically as a function of largely dormant cells and/or retained dynamically by more transitory subpopulations. To explore the origins of immunological memory, we measured the turnover of T SCM cells in vivo using stable isotope labeling with heavy water. The data indicate that T SCM cells in both young and elderly subjects are maintained by ongoing proliferation. In line with this finding, T SCM cells displayed limited telomere length erosion coupled with high expression levels of active telomerase and Ki67. Collectively, these observations show that T SCM cells exist in a state of perpetual flux throughout the human lifespan. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Guanylate-binding protein-1 is a potential new therapeutic target for triple-negative breast cancer.

PubMed

Quintero, Melissa; Adamoski, Douglas; Reis, Larissa Menezes Dos; Ascenção, Carolline Fernanda Rodrigues; Oliveira, Krishina Ratna Sousa de; Gonçalves, Kaliandra de Almeida; Dias, Marília Meira; Carazzolle, Marcelo Falsarella; Dias, Sandra Martha Gomes

2017-11-07

Triple-negative breast cancer (TNBC) is characterized by a lack of estrogen and progesterone receptor expression (ESR and PGR, respectively) and an absence of human epithelial growth factor receptor (ERBB2) amplification. Approximately 15-20% of breast malignancies are TNBC. Patients with TNBC often have an unfavorable prognosis. In addition, TNBC represents an important clinical challenge since it does not respond to hormone therapy. In this work, we integrated high-throughput mRNA sequencing (RNA-Seq) data from normal and tumor tissues (obtained from The Cancer Genome Atlas, TCGA) and cell lines obtained through in-house sequencing or available from the Gene Expression Omnibus (GEO) to generate a unified list of differentially expressed (DE) genes. Methylome and proteomic data were integrated to our analysis to give further support to our findings. Genes that were overexpressed in TNBC were then curated to retain new potentially druggable targets based on in silico analysis. Knocking-down was used to assess gene importance for TNBC cell proliferation. Our pipeline analysis generated a list of 243 potential new targets for treating TNBC. We finally demonstrated that knock-down of Guanylate-Binding Protein 1 (GBP1 ), one of the candidate genes, selectively affected the growth of TNBC cell lines. Moreover, we showed that GBP1 expression was controlled by epidermal growth factor receptor (EGFR) in breast cancer cell lines. We propose that GBP1 is a new potential druggable therapeutic target for treating TNBC with enhanced EGFR expression.
Single-copy gene detection using branched DNA (bDNA) in situ hybridization.

PubMed

Player, A N; Shen, L P; Kenny, D; Antao, V P; Kolberg, J A

2001-05-01

We have developed a branched DNA in situ hybridization (bDNA ISH) method for detection of human papillomavirus (HPV) DNA in whole cells. Using human cervical cancer cell lines with known copies of HPV DNA, we show that the bDNA ISH method is highly sensitive, detecting as few as one or two copies of HPV DNA per cell. By modifying sample pretreatment, viral mRNA or DNA sequences can be detected using the same set of oligonucleotide probes. In experiments performed on mixed populations of cells, the bDNA ISH method is highly specific and can distinguish cells with HPV-16 from cells with HPV-18 DNA. Furthermore, we demonstrate that the bDNA ISH method provides precise localization, yielding positive signals retained within the subcellular compartments in which the target nucleic acid sequences are localized. As an effective and convenient means for nucleic acid detection, the bDNA ISH method is applicable to the detection of cancers and infectious agents. (J Histochem Cytochem 49:603-611, 2001)
Post-secretory fate of host defence components in mucus.

PubMed

Salathe, Matthias; Forteza, Rosanna; Conner, Gregory E

2002-01-01

Airway mucus is a complex mixture of secretory products that provide a multifaceted defence against infection. Among many antimicrobial substances, mucus contains a peroxidase identical to milk lactoperoxidase (LPO) that is produced by goblet cells and submucosal glands. Airway secretions contain the substrates for LPO, namely thiocyanate and hydrogen peroxide, at concentrations sufficient for production of the biocidal compound hypothiocyanite, a fact confirmed by us in vitro. In vivo, inhibition of airway LPO in sheep significantly inhibits bacterial clearance, suggesting that the LPO system is a major contributor to host defences. Since secretory products including LPO are believed to be steadily removed by mucociliary clearance, their amount and availability on the surface is thought to be controlled solely by secretion. In contrast to this paradigm, new data suggest that LPO and other substances are retained at the ciliary border of the airway epithelium by binding to surface-associated hyaluronan, thereby providing an apical, fully active enzyme pool. Thus, hyaluronan, secreted from submucosal gland cells, plays a previously unrecognized pivotal role in mucosal host defence by retaining LPO and possibly other substances important for first line host defence at the apical surface 'ready for use' and protected from ciliary clearance.
Biarylmethoxy Nicotinamides As Novel and Specific Inhibitors of Mycobacterium tuberculosis.

PubMed

Kedari, Chaitanya Kumar; Roy Choudhury, Nilanjana; Sharma, Sreevalli; Kaur, Parvinder; Guptha, Supreeth; Panda, Manoranjan; Mukerjee, Kakoli; Ramachandran, Vasanthi; Bandodkar, Balachandra; Ramachandran, Sreekanth; Tantry, Subramanyam J

2014-05-08

A whole cell based screening effort on a focused library from corporate collection resulted in the identification of biarylmethoxy nicotinamides as novel inhibitors of M. tuberculosis (Mtu) H37Rv. The series exhibited tangible structure-activity relationships, and during hit to lead exploration, a cellular potency of 100 nM was achieved, which is an improvement of >200-fold from the starting point. The series is very specific to Mtu and noncytotoxic up to 250 μM as measured in the mammalian cell line THP-1 based cytotoxicity assay. This compound class retains its potency on several drug sensitive and single drug resistant clinical isolates, which indicate that the compounds could be acting through a novel mode of action.
Trypanosoma brucei (UMP synthase null mutants) are avirulent in mice, but recover virulence upon prolonged culture in vitro while retaining pyrimidine auxotrophy

PubMed Central

Ong, Han B; Sienkiewicz, Natasha; Wyllie, Susan; Patterson, Stephen; Fairlamb, Alan H

2013-01-01

African trypanosomes are capable of both de novo synthesis and salvage of pyrimidines. The last two steps in de novo synthesis are catalysed by UMP synthase (UMPS) – a bifunctional enzyme comprising orotate phosphoribosyl transferase (OPRT) and orotidine monophosphate decarboxylase (OMPDC). To investigate the essentiality of pyrimidine biosynthesis in Trypanosoma brucei, we generated a umps double knockout (DKO) line by gene replacement. The DKO was unable to grow in pyrimidine-depleted medium in vitro, unless supplemented with uracil, uridine, deoxyuridine or UMP. DKO parasites were completely resistant to 5-fluoroorotate and hypersensitive to 5-fluorouracil, consistent with loss of UMPS, but remained sensitive to pyrazofurin indicating that, unlike mammalian cells, the primary target of pyrazofurin is not OMPDC. The null mutant was unable to infect mice indicating that salvage of host pyrimidines is insufficient to support growth. However, following prolonged culture in vitro, parasites regained virulence in mice despite retaining pyrimidine auxotrophy. Unlike the wild-type, both pyrimidine auxotrophs secreted substantial quantities of orotate, significantly higher in the virulent DKO line. We propose that this may be responsible for the recovery of virulence in mice, due to host metabolism converting orotate to uridine, thereby bypassing the loss of UMPS in the parasite. PMID:23980694
Cellular cooperation in lymphocyte activation. III. B-cell helper effect in the enhancement of T-cell response.

PubMed

Kasahara, T; Kin, K; Itoh, Y; Kawai, T; Kano, Y; Shioiri-Nakano, K

1979-01-01

T and B cells were purified from human tonsil and peripheral blood by the removal of phagocytic cells, followed by filtration through a nylon fiber column (NC) and E-rosette formation. Purified T and B cells contained less than 1% of other cell types. The responses of T cells to concanavalin A (Con A) and soluble protein A were greatly enhanced in the presence of autologous B cells. Participation of B cells in T-cell enhancement was confirmed by the following observations: (a) purified B copulation, which was separated further from adherent B cells, retained its enhancing activity. (b) Another adherent cell-free B-cell preparation, which was purified from the NC-passed fraction, and (c) no T lymphoid but some B lymphoid cell lines, elicited strong T-cell enhancement. It was also found that the enhancing capacity of B cells required no metabolic activity, but rather an intact cell form and direct cell-to-cell contact with responding cells. The stimulatory determinants on B cells were resistant to trypsin and neuraminidase treatment. In this paper a hypothesis will be presented that at least two signals are prerequisite for the effective activation of T cells.
Evidence for label-retaining tumour-initiating cells in human glioblastoma

PubMed Central

Deleyrolle, Loic P.; Harding, Angus; Cato, Kathleen; Siebzehnrubl, Florian A.; Rahman, Maryam; Azari, Hassan; Olson, Sarah; Gabrielli, Brian; Osborne, Geoffrey; Vescovi, Angelo

2011-01-01

Individual tumour cells display diverse functional behaviours in terms of proliferation rate, cell–cell interactions, metastatic potential and sensitivity to therapy. Moreover, sequencing studies have demonstrated surprising levels of genetic diversity between individual patient tumours of the same type. Tumour heterogeneity presents a significant therapeutic challenge as diverse cell types within a tumour can respond differently to therapies, and inter-patient heterogeneity may prevent the development of general treatments for cancer. One strategy that may help overcome tumour heterogeneity is the identification of tumour sub-populations that drive specific disease pathologies for the development of therapies targeting these clinically relevant sub-populations. Here, we have identified a dye-retaining brain tumour population that displays all the hallmarks of a tumour-initiating sub-population. Using a limiting dilution transplantation assay in immunocompromised mice, label-retaining brain tumour cells display elevated tumour-initiation properties relative to the bulk population. Importantly, tumours generated from these label-retaining cells exhibit all the pathological features of the primary disease. Together, these findings confirm dye-retaining brain tumour cells exhibit tumour-initiation ability and are therefore viable targets for the development of therapeutics targeting this sub-population. PMID:21515906
Generation and characterization of a spontaneously immortalized endothelial cell line from mice microcirculation.

PubMed

Loiola, Rodrigo A; Torres, Tathiany C; Aburaya, Carla M; Landgraf, Maristella A; Landgraf, Richardt G; Bosco Pesquero, João; Fernandes, Liliam

2013-05-01

Endothelial cells from microvasculature are directly involved in a large number of vascular diseases; however, culture of these cells is problematic, since most methodologies employ proteolytic enzymes or mechanical techniques, leading to cell damage and contamination of endothelial cultures with other cellular types. Besides, primary cultured cells have a short life span in vitro and undergo replicative senescence after 3-4 passages, limiting long-term studies. In the present work we report the generation of a spontaneously immortalized endothelial culture obtained from mice pulmonary capillaries. Firstly, primary (third passage) and immortalized (100th) cultures were established. Further, monoclonal populations were obtained by serial dilutions from immortalized cultures. Cells were analyzed according to: (1) morphological appearance, (2) expression of specific endothelial markers by fluorescent staining [von Willebrand Factor (vWF), endothelial nitric oxide synthase (eNOS), angiotensin converting enzyme (ACE) and Ulex europaeus (UEA-1)] and by flow cytometry (endoglin, VE-cadherin and VCAM-1), and (3) release of nitric oxide (NO), assessed by the specific fluorescent dye DAF-2 DA, and prostacyclin (PGI2), quantified by enzyme immune assay. In both cultures cells grew in monolayers and presented cobblestone appearance at confluence. Positive staining for vWF, eNOS, ACE and UEA-1 was detected in cloned as well as in early-passage cultured cells. Similarly, cultures presented equal expressions of endoglin, VE-cadherin and VCAM-1. Values of NO and PGI2 levels did not differ between cultures. From these results we confirm that the described spontaneously immortalized endothelial cell line is capable of unlimited growth and retains typical morphological and functional properties exhibited by primary cultured cells. Therefore, the endothelial cell line described in the present study can become a suitable tool in the field of endothelium research and can be useful for the investigation of production of endothelial mediators, angiogenesis and inflammation. Copyright © 2013 Elsevier Inc. All rights reserved.
A Method for the Immortalization of Newborn Mouse Skin Keratinocytes

PubMed Central

Hammiller, Brianna O.; El-Abaseri, Taghrid Bahig; Dlugosz, Andrzej A.; Hansen, Laura A.

2015-01-01

Isolation and culture of mouse primary epidermal keratinocytes is a common technique that allows for easy genetic and environmental manipulation. However, due to their limited lifespan in culture, experiments utilizing primary keratinocytes require large numbers of animals, and are time consuming and expensive. To avoid these issues, we developed a method for the immortalization of primary mouse epidermal keratinocytes. Upon isolation of newborn epidermal keratinocytes according to established methods, the cells were cultured long-term in keratinocyte growth factor-containing medium. The cells senesced within a few weeks and eventually, small, slowly growing colonies emerged. After they regained confluency, the cells were passaged and slowly refilled the dish. With several rounds of subculture, the cells adapted to culture conditions, were easily subcultured, maintained normal morphology, and were apparently immortal. The immortalized cells retained the ability to differentiate with increased calcium concentrations, and were maintained to high passage numbers while maintaining a relatively stable karyotype. Analysis of multiple immortalized cell lines as well as primary keratinocyte cultures revealed increased numbers of chromosomes, especially in the primary keratinocytes, and chromosomal aberrations in most of the immortalized cultures and in the primary keratinocytes. Orthotopic grafting of immortalized keratinocytes together with fibroblasts onto nude mouse hosts produced skin while v-rasHa infection of the immortalized keratinocytes prior to grafting produced squamous cell carcinoma. In summary, this method of cell line generation allows for decreased use of animals, reduces the expense and time involved in research, and provides a useful model for cutaneous keratinocyte experimentation. PMID:26284198
Follicular Dendritic Cells Retain Infectious HIV in Cycling Endosomes

PubMed Central

Heesters, Balthasar A.; Lindqvist, Madelene; Vagefi, Parsia A.; Scully, Eileen P.; Schildberg, Frank A.; Altfeld, Marcus; Walker, Bruce D.; Kaufmann, Daniel E.; Carroll, Michael C.

2015-01-01

Despite the success of antiretroviral therapy (ART), it does not cure Human Immunodeficiency Virus (HIV) and discontinuation results in viral rebound. Follicular dendritic cells (FDC) are in direct contact with CD4+ T cells and they retain intact antigen for prolonged periods. We found that human FDC isolated from patients on ART retain infectious HIV within a non-degradative cycling compartment and transmit infectious virus to uninfected CD4 T cells in vitro. Importantly, treatment of the HIV+ FDC with a soluble complement receptor 2 purges the FDC of HIV virions and prevents viral transmission in vitro. Our results provide an explanation for how FDC can retain infectious HIV for extended periods and suggest a therapeutic strategy to achieve cure in HIV-infected humans. PMID:26623655
Novel kinase fusion transcripts found in endometrial cancer

PubMed Central

Tamura, Ryo; Yoshihara, Kosuke; Yamawaki, Kaoru; Suda, Kazuaki; Ishiguro, Tatsuya; Adachi, Sosuke; Okuda, Shujiro; Inoue, Ituro; Verhaak, Roel G. W.; Enomoto, Takayuki

2015-01-01

Recent advances in RNA-sequencing technology have enabled the discovery of gene fusion transcripts in the transcriptome of cancer cells. However, it remains difficult to differentiate the therapeutically targetable fusions from passenger events. We have analyzed RNA-sequencing data and DNA copy number data from 25 endometrial cancer cell lines to identify potential therapeutically targetable fusion transcripts, and have identified 124 high-confidence fusion transcripts, of which 69% are associated with gene amplifications. As targetable fusion candidates, we focused on three in-frame kinase fusion transcripts that retain a kinase domain (CPQ-PRKDC, CAPZA2-MET, and VGLL4-PRKG1). We detected only CPQ-PRKDC fusion transcript in three of 122 primary endometrial cancer tissues. Cell proliferation of the fusion-positive cell line was inhibited by knocking down the expression of wild-type PRKDC but not by blocking the CPQ-PRKDC fusion transcript expression. Quantitative real-time RT-PCR demonstrated that the expression of the CPQ-PRKDC fusion transcript was significantly lower than that of wild-type PRKDC, corresponding to a low transcript allele fraction of this fusion, based on RNA-sequencing read counts. In endometrial cancers, the CPQ-PRKDC fusion transcript may be a passenger aberration related to gene amplification. Our findings suggest that transcript allele fraction is a useful predictor to find bona-fide therapeutic-targetable fusion transcripts. PMID:26689674
Novel kinase fusion transcripts found in endometrial cancer.

PubMed

Tamura, Ryo; Yoshihara, Kosuke; Yamawaki, Kaoru; Suda, Kazuaki; Ishiguro, Tatsuya; Adachi, Sosuke; Okuda, Shujiro; Inoue, Ituro; Verhaak, Roel G W; Enomoto, Takayuki

2015-12-22

Recent advances in RNA-sequencing technology have enabled the discovery of gene fusion transcripts in the transcriptome of cancer cells. However, it remains difficult to differentiate the therapeutically targetable fusions from passenger events. We have analyzed RNA-sequencing data and DNA copy number data from 25 endometrial cancer cell lines to identify potential therapeutically targetable fusion transcripts, and have identified 124 high-confidence fusion transcripts, of which 69% are associated with gene amplifications. As targetable fusion candidates, we focused on three in-frame kinase fusion transcripts that retain a kinase domain (CPQ-PRKDC, CAPZA2-MET, and VGLL4-PRKG1). We detected only CPQ-PRKDC fusion transcript in three of 122 primary endometrial cancer tissues. Cell proliferation of the fusion-positive cell line was inhibited by knocking down the expression of wild-type PRKDC but not by blocking the CPQ-PRKDC fusion transcript expression. Quantitative real-time RT-PCR demonstrated that the expression of the CPQ-PRKDC fusion transcript was significantly lower than that of wild-type PRKDC, corresponding to a low transcript allele fraction of this fusion, based on RNA-sequencing read counts. In endometrial cancers, the CPQ-PRKDC fusion transcript may be a passenger aberration related to gene amplification. Our findings suggest that transcript allele fraction is a useful predictor to find bona-fide therapeutic-targetable fusion transcripts.
IS MAGNETIC RECONNECTION THE CAUSE OF SUPERSONIC UPFLOWS IN GRANULAR CELLS?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borrero, J. M.; Schmidt, W.; Martinez Pillet, V.

In a previous work, we reported on the discovery of supersonic magnetic upflows on granular cells in data from the SUNRISE/IMaX instrument. In the present work, we investigate the physical origin of these events employing data from the same instrument but with higher spectral sampling. By means of the inversion of Stokes profiles we are able to recover the physical parameters (temperature, magnetic field, line-of-sight velocity, etc.) present in the solar photosphere at the time of these events. The inversion is performed in a Monte-Carlo-like fashion, that is, repeating it many times with different initializations and retaining only the bestmore » result. We find that many of the events are characterized by a reversal in the polarity of the magnetic field along the vertical direction in the photosphere, accompanied by an enhancement in the temperature and by supersonic line-of-sight velocities. In about half of the studied events, large blueshifted and redshifted line-of-sight velocities coexist above/below each other. These features can be explained in terms of magnetic reconnection, where the energy stored in the magnetic field is released in the form of kinetic and thermal energy when magnetic field lines of opposite polarities coalesce. However, the agreement with magnetic reconnection is not perfect and, therefore, other possible physical mechanisms might also play a role.« less
The bovine placenta in vivo and in vitro.

PubMed

Haeger, J-D; Hambruch, N; Pfarrer, C

2016-07-01

The gross anatomic features (cotyledonary type) and histologic classification (synepitheliochorial) of the bovine placenta have been known for many years. Thorough ultrastructural analysis as well as a variety of descriptive studies dealing with the localization of cytoskeletal filaments, extracellular matrix, growth factor systems, steroid hormone receptors, and major histocompatibility complex have contributed further significant knowledge. However, this knowledge was not sufficient to solve clinical placenta-based problems, such as retained fetal membranes. Owing to the complexity of the fetomaternal interface in vitro, culture systems have been developed. As trophoblast giant cells (TGC) are thought to be key players in the cattle placenta, most cell culture models attempt to overcome the pitfall of losing the entire TGC population in vitro. Nevertheless, distinct cell line-based in vitro systems such as cell monolayers or 3-dimensional (co-culture) spheroids were generated for the fetal (trophoblast) and maternal (uterine epithelium) placental compartments. Monolayers have been used to study for example, growth factor or hormonal signaling and TGC formation, whereas spheroids served as models for, for example, trophoblast attachment, uterine epithelium depolarization, and also TGC formation. In the future, the use of more improved culture models might lead to better treatments of retained fetal membranes and increased prevention of embryonic loss. In addition, the in vitro models could shed more light on the mechanisms of the differentiation of uninucleate trophoblast into TGC. Copyright © 2016 Elsevier Inc. All rights reserved.

Expression and activity of multidrug resistance protein 1 in a murine thymoma cell line

PubMed Central

Echevarria-Lima, Juliana; Kyle-Cezar, Fernanda; Leite, Daniela F P; Capella, Luiz; Capella, Márcia A M; Rumjanek, Vivian M

2005-01-01

Multidrug resistance proteins [MRPs and P-glycoprotein (Pgp)] are members of the family of ATP-binding cassette (ABC) transport proteins, originally described as being involved in the resistance against anti-cancer agents in tumour cells. These proteins act as ATP-dependent efflux pumps and have now been described in normal cells where they exert physiological roles. The aim of this work was to investigate the expression and activity of MRP and Pgp in the thymoma cell line, EL4. It was observed that EL4 cells expressed mRNA for MRP1, but not for MRP2, MRP3 or Pgp. The activity of ABC transport proteins was evaluated by using the efflux of the fluorescent probes carboxy-2′-7′-dichlorofluorescein diacetate (CFDA) and rhodamine 123 (Rho 123). EL4 cells did not retain CFDA intracellularly, and MRP inhibitors (probenecid, indomethacin and MK 571) decreased MRP1 activity in a concentration-dependent manner. As expected, EL4 cells accumulated Rho 123, and the presence of cyclosporin A and verapamil did not modify this accumulation. Most importantly, when EL4 cells were incubated in the presence of the MRP1 inhibitors indomethacin and MK 571 for 6 days, they started to express CD4 and CD8 molecules on their surface, producing double-positive cells and CD8 single-positive cells. Our results suggest that MRP activity is important for the maintenance of the undifferentiated state in this cell type. This finding might have implications in the physiological process of normal thymocyte maturation. PMID:15804283
A serum factor promotes collagenase synthesis by an osteoblastic cell line

NASA Technical Reports Server (NTRS)

Puccinelli, J. M.; Omura, T. H.; Strege, D. W.; Jeffrey, J. J.; Partridge, N. C.

1991-01-01

Regulation of the synthesis of collagenase was investigated in the osteoblastic cell line, UMR 106-01. The cells were stained by the avidin-biotin-complex technique for the presence of the enzyme. By this method, it was possible to identify cells producing collagenase. Synthesis, but not secretion, was found to be constitutive in these cells with the enzyme located intracellularly in cytoplasmic vesicles and the Golgi apparatus. The amount of collagenase contained within UMR cells and the number of cells synthesizing the enzyme were proportional to the concentration of fetal bovine serum in the incubating medium. When serum was withdrawn from the osteosarcoma cells, the content of collagenase decreased with time and the enzyme became undetectable by 48 h of serum depletion. The decrease in collagenase content could be completely reversed by resupplying serum to the cells. The collagenase promoting activity of serum could not be eliminated by adsorption on activated charcoal but was retained by a dialysis membrane with a 12,000 mol wt cutoff. A range of bone-seeking hormones or agents known to affect collagenase secretion was added to the medium in an attempt to mimic the effect of serum on collagenase accumulation. None of these agonists, including parathyroid hormone, could reproduce the effect of serum on these cells, although parathyroid hormone could act as a collagenase secretagogue in the presence or absence of serum. It is concluded that fetal bovine serum contains a yet unidentified factor or factors greater than 12,000 mol wt responsible for the continued synthesis of collagenase by UMR 106-01 cells.
Rapid obtention of stable, bioluminescent tumor cell lines using a tCD2-luciferase chimeric construct

PubMed Central

2011-01-01

Background Bioluminescent tumor cell lines are experimental tools of major importance for cancer investigation, especially imaging of tumors in xenografted animals. Stable expression of exogenous luciferase in tumor cells combined to systemic injection of luciferin provides an excellent signal/background ratio for external optical imaging. Therefore, there is a need to rationalize and speed up the production of luciferase-positive tumor cell lines representative of multiple tumor phenotypes. For this aim we have designed a fusion gene linking the luciferase 2 protein to the c-terminus of a truncated form of the rat CD2 protein (tCD2-luc2). To allow simultaneous assessment of the wild-type luciferase 2 in a context of tCD2 co-expression, we have made a bicistronic construct for concomitant but separate expression of these two proteins (luc2-IRES-tCD2). Both the mono- and bi-cistronic constructs were transduced in lymphoid and epithelial cells using lentiviral vectors. Results The tCD2-luc2 chimera behaves as a type I membrane protein with surface presentation of CD2 epitopes. One of these epitopes reacts with the OX34, a widely spread, high affinity monoclonal antibody. Stably transfected cells are sorted by flow cytometry on the basis of OX34 staining. In vitro and, moreover, in xenografted tumors, the tCD2-luc2 chimera retains a substantial and stable luciferase activity, although not as high as the wild-type luciferase expressed from the luc2-IRES-tCD2 construct. Expression of the tCD2-luc2 chimera does not harm cell and tumor growth. Conclusion Lentiviral transduction of the chimeric tCD2-luc2 fusion gene allows selection of cell clones with stable luciferase expression in less than seven days without antibiotic selection. We believe that it will be helpful to increase the number of tumor cell lines available for in vivo imaging and assessment of novel therapeutic modalities. On a longer term, the tCD2-luc2 chimera has the potential to be expressed from multi-cassette vectors in combination with various inserts of interest. PMID:21435248
Design, synthesis of methotrexate-diosgenin conjugates and biological evaluation of their effect on methotrexate transport-resistant cells.

PubMed

Cai, Bangrong; Liao, Aimei; Lee, Kyung-Ku; Ban, Jae-Sam; Yang, Hyun-Sam; Im, Young Jun; Chun, ChangJu

2016-12-01

A series of methotrexate-diosgenin conjugates was designed and synthesized to enhance the passive internalization of methotrexate (MTX) into transport-resistant cells. The inhibitory effects of these conjugates on dihydrofolate reductase (DHFR), and their anti-proliferation behaviors against a transport-resistant breast cancer cell line, MDA-MB-231, were investigated. All of the synthesized conjugates retained an ability to inhibit DHFR after the diosgenin substitution. The MTX conjugates were much more potent against methotrexate-resistant MDA-MB-231 cells than MTX. Conjugate 18, containing a disulfide bond, exhibited the most potent anti-proliferative and DHFR inhibitory effects (IC 50 =4.1μM and 17.21nM, respectively). Anti-proliferative activity was higher in the conjugate with a longer space linker (conjugate 21) than those with shorter linkers (conjugates 19 and 20). These results suggest that diosgenin conjugation of MTX may be an effective way to overcome its transport resistance in cancer cells. Copyright Â© 2016 Elsevier Inc. All rights reserved.
cld and lec23 are disparate mutations that affect maturation of lipoprotein lipase in the endoplasmic reticulum.

PubMed

Briquet-Laugier, V; Ben-Zeev, O; White, A; Doolittle, M H

1999-11-01

The mutations cld (combined lipase deficiency) and lec23 disrupt in a similar manner the expression of lipoprotein lipase (LPL). Whereas cld affects an unknown gene, lec23 abolishes the activity of alpha-glucosidase I, an enzyme essential for proper folding and assembly of nascent glycoproteins. The hypothesis that cld, like lec23, affects the folding/assembly of nascent LPL was confirmed by showing that in cell lines homozygous for these mutations (Cld and Lec23, respectively), the majority of LPL was inactive, displayed heterogeneous aggregation, and had a decreased affinity for heparin. While inactive LPL was retained in the ER, a small amount of LPL that had attained a native conformation was transported through the Golgi and secreted. Thus, Cld and Lec23 cells recognized and retained the majority of LPL as misfolded, maintaining the standard of quality control. Examination of candidate factors affecting protein maturation, such as glucose addition and trimming, proteins involved in lectin chaperone cycling, and other abundant ER chaperones, revealed that calnexin levels were dramatically reduced in livers from cld/cld mice; this finding was also confirmed in Cld cells. We conclude that cld may affect components in the ER, such as calnexin, that play a role in protein maturation. Whether the reduced calnexin levels per se contribute to the LPL deficiency awaits confirmation.
40 CFR 94.509 - Maintenance of records; submittal of information.

Code of Federal Regulations, 2010 CFR

2010-07-01

... all testing. Records may be retained as hard copy (i.e., on paper) or reduced to microfilm, floppy... procedure; provided, that in every case, all the information contained in the hard copy is retained. (c) The... production line testing using an EPA information format. ...
Electrospun nanofibrous scaffolds increase the efficacy of stem cell-mediated therapy of surgically resected glioblastoma

PubMed Central

Bagó, Juli R.; Pegna, Guillaume J.; Okolie, Onyi; Mohiti-Asli, Mahsa; Loboa, Elizabeth G.; Hingtgen, Shawn D.

2017-01-01

Engineered stem cell (SC)-based therapy holds enormous promise for treating the incurable brain cancer glioblastoma (GBM). Retaining the cytotoxic SCs in the surgical cavity after GBM resection is one of the greatest challenges to this approach. Here, we describe a biocompatible electrospun nanofibrous scaffold (bENS) implant capable of delivering and retaining tumor-homing cytotoxic stem cells that suppress recurrence of post-surgical GBM. As a new approach to GBM therapy, we created poly(l-lactic acid) (PLA) bENS bearing drug-releasing human mesenchymal stem cells (hMSCs). We discovered that bENS-based implant increased hMSC retention in the surgical cavity 5-fold and prolonged persistence 3-fold compared to standard direct injection using our mouse model of GBM surgical resection/recurrence. Time-lapse imaging showed cytotoxic hMSC/bENS treatment killed co-cultured human GBM cells, and allowed hMSCs to rapidly migrate off the scaffolds as they homed to GBMs. In vivo, bENS loaded with hMSCs releasing the anti-tumor protein TRAIL (bENSsTR) reduced the volume of established GBM xenografts 3-fold. Mimicking clinical GBM patient therapy, lining the post-operative GBM surgical cavity with bENSsTR implants inhibited the re-growth of residual GBM foci 2.3-fold and prolonged post-surgical median survival from 13.5 to 31 days in mice. These results suggest that nanofibrous-based SC therapies could be an innovative new approach to improve the outcomes of patients suffering from terminal brain cancer. PMID:27016620
Differential effect of combined lipase deficiency (cld/cld) on human hepatic lipase and lipoprotein lipase secretion.

PubMed

Boedeker, J C; Doolittle, M H; White, A L

2001-11-01

Combined lipase deficiency (cld) is a recessively inherited disorder in mice associated with a deficiency of LPL and hepatic lipase (HL) activity. LPL is synthesized in cld tissues but is retained in the endoplasmic reticulum (ER), whereas mouse HL (mHL) is secreted but inactive. In this study we investigated the effect of cld on the secretion of human HL (hHL) protein mass and activity. Differentiated liver cell lines were derived from cld mice and their normal heterozygous (het) littermates by transformation of hepatocytes with SV40 large T antigen. After transient transfection with lipase expression constructs, secretion of hLPL activity from cld cells was only 12% of that from het cells. In contrast, the rate of secretion of hHL activity and protein mass per unit of expressed hHL mRNA was identical for the two cell lines. An intermediate effect was observed for mHL, with a 46% reduction in secretion of activity from cld cells. The ER glucosidase inhibitor, castanospermine, decreased secretion of both hLPL and hHL from het cells by approximately 70%, but by only approximately 45% from cld cells. This is consistent with data suggesting that cld may result from a reduced concentration of the ER chaperone calnexin. In conclusion, our results demonstrate a differential effect of cld on hLPL, mHL, and hHL secretion, suggesting differential requirements for activation and exit of the enzymes from the ER.
Targeted inhibition of osteosarcoma tumor growth by bone marrow-derived mesenchymal stem cells expressing cytosine deaminase/5-fluorocytosine in tumor-bearing mice.

PubMed

NguyenThai, Quynh-Anh; Sharma, Neelesh; Luong, Do Huynh; Sodhi, Simrinder Singh; Kim, Jeong-Hyun; Kim, Nameun; Oh, Sung-Jong; Jeong, Dong Kee

2015-01-01

Mesenchymal stem cells (MSCs) are considered as an attractive approach for gene or drug delivery in cancer therapy. In the present study, the ability of human bone marrow-derived MSCs expressing the cytosine deaminase/5-fluorocytosine prodrug (CD/5-FC MSCs) to target the human osteosarcoma cell line Cal72 was evaluated. The stable CD/5-FC MSC cell line was established by transfection of pEGFP containing the cytosine deaminase gene into MSCs with G418 selection. The anti-tumor effect was verified by a bystander effect assay in vitro and co-injection of Cal72 and CD/5-FC MSCs in cancer-bearing mice. The therapeutic CD/5-FC MSCs retained the characteristics of multipotent cells, such as differentiation into adipocytes/osteocytes and expression of mesenchymal markers (CD90 and CD44), and showed migration toward Cal72 cells to a greater extent than the native MSCs. The bystander effect assay showed that the CD/5-FC MSCs significantly augmented Cal72 cytotoxicity in direct co-culture and in the presence of 5-FC through the application of conditioned medium. In osteosarcoma-bearing mice, the CD/5-FC MSCs inhibited tumor growth compared to control mice subcutaneously injected with only Cal72 cells. Taken together, these findings suggest that CD/5-FC MSCs may be suitable for targeting human osteosarcoma. Copyright © 2015 John Wiley & Sons, Ltd.
Conserved and non-conserved characteristics of porcine glial cell line-derived neurotrophic factor expressed in the testis.

PubMed

Kakiuchi, Kazue; Taniguchi, Kazumi; Kubota, Hiroshi

2018-05-16

Glial cell line-derived neurotrophic factor (GDNF) is essential for the self-renewal and proliferation of spermatogonial stem cells (SSCs) in mice, rats, and rabbits. Although the key extrinsic factors essential for spermatogonial proliferation in other mammals have not been determined, GDNF is one of the potential candidates. In this study, we isolated porcine GDNF (pGDNF) cDNAs from neonatal testis and generated recombinant pGDNF to investigate its biological activity on gonocytes/undifferentiated spermatogonia, including SSCs. In porcine testis, long and short forms of GDNF transcripts, the counterparts of pre-(α)pro and pre-(β)pro GDNF identified in humans and rodents, were expressed. The two transcripts encode identical mature proteins. Recombinant pGDNF supported proliferation of murine SSCs in culture, and their stem cell activity was confirmed by a transplantation assay. Subsequently, porcine gonocytes/undifferentiated spermatogonia were cultured with pGDNF; however, pGDNF did not affect their proliferation. Furthermore, GDNF expression was localised to the vascular smooth muscle cells, and its cognate receptor GFRA1 expression was negligible during spermatogonial proliferation in the testes. These results indicate that although pGDNF retains structural similarity with those of other mammals and conserves the biological activity on the self-renewal of murine SSCs, porcine SSCs likely require extrinsic factors other than GDNF for their proliferation.
Comparison of cytotoxicity, genotoxicity and immunological inflammatory biomarker activity of several endodontic sealers against immortalized human pulp cells.

PubMed

Martinho, F C; Camargo, S E A; Fernandes, A M M; Campos, M S; Prado, R F; Camargo, C H R; Valera, M C

2018-01-01

To establish an SV40 T-Ag-transfected cell line of human pulp-derived cells in order to compare the cytotoxicity, genotoxicity and to investigate the activities of immunological biomarkers of several endodontic sealers. Primary human pulp cells and transfected cells were cultured. Cell morphology and proliferation were analysed, and the expression of cell-specific gene transcripts and proteins was detected by RT-PCR and immunohistochemistry. Transfection of human pulp-derived cells resulted in an immortalized cell line retaining phenotypic characteristics from the primarily cells tested. The SV40 T-Ag-transfected cells were cultured and stimulated by sealers (Apexit Plus, Real Seal, AH Plus, and EndoREZ) to evaluate the cytotoxicity and genotoxicity by MTT and MTN assays, respectively. Immunological inflammatory biomarkers (IL6, IL8 and TNF-α) were determined by ELISA assay. The differences between median values were statistically analysed using Kruskal-Wallis and Dunn's tests at 5% significance level. The cytotoxicity assay revealed that multimethacrylate (Real Seal) was the most cytotoxic sealer (P < 0.05) and exhibited the highest inflammatory potential against the SV40 T-Ag-transfected cells (P < 0.05). All root canal sealers tested were able to stimulate the immortalized pulp cells to produce IL-6, IL-8 and TNF-α, with differences in relation to the control group (P < 0.05). Higher levels of IL-6, IL-8 and TNF-α were found in cell supernatant after stimulation with multimethacrylate (Real Seal) compared to all other sealers tested (P < 0.05). No differences were found comparing epoxy resin-based sealer (AHPlus), single-methacrylate sealer (EndoREZ) and calcium hydroxide-based sealer (Apexit Plus), regardless of the cytokine investigated (all P > 0.05). A SV40 T-Ag-transfected cell line of human pulp-derived cells was established. The methacrylate resin-based sealer (Real Seal) exhibited the greatest cytoxicity and inflammatory potential against immortalized pulp cells compared to an epoxy resin-based sealer (AH Plus), a methacrylate-based sealer (EndoRez) and a calcium hydroxide-based sealer (Apexit). © 2017 International Endodontic Journal. Published by John Wiley & Sons Ltd.
40 CFR 90.704 - Maintenance of records; submission of information.

Code of Federal Regulations, 2010 CFR

2010-07-01

... testing required for the engine family in a model year. Records may be retained as hard copy (i.e., on... hard copy is retained. (c) The manufacturer must, upon request by the Administrator, submit the... production line testing using EPA's standardized format. The Administrator may exempt manufacturers from this...
40 CFR 98.67 - Records that must be retained.

Code of Federal Regulations, 2010 CFR

2010-07-01

... prebake and Sderberg electolysis cells. (2) Anode effect minutes per cell-day (AE-mins/cell-day), anode...-specific information for Sderberg cells: (1) Annual paste consumption. (2) Annual CO2 emissions from the... addition to the information required by § 98.3(g), you must retain the following records: (a) Monthly...
Yap is required for ependymal integrity and is suppressed in LPA-induced hydrocephalus

PubMed Central

Park, Raehee; Moon, Uk Yeol; Park, Jun Young; Hughes, Lucinda J.; Johnson, Randy L.; Cho, Seo-Hee; Kim, Seonhee

2016-01-01

Timely generation and normal maturation of ependymal cells along the aqueduct are critical for preventing physical blockage between the third and fourth ventricles and the development of fetal non-communicating hydrocephalus. Our study identifies Yap, the downstream effector of the evolutionarily conserved Hippo pathway, as a central regulator for generating developmentally controlled ependymal cells along the ventricular lining of the aqueduct. Yap function is necessary for proper proliferation of progenitors and apical attachment of ependymal precursor cells. Importantly, an injury signal initiated by lysophosphatidic acid (LPA), an upstream regulator of Yap that can cause fetal haemorrhagic hydrocephalus, deregulates Yap in the developing aqueduct. LPA exposure leads to the loss of N-cadherin concentrations at the apical endfeet, which can be partially restored by forced Yap expression and more efficiently by phosphomimetic Yap. These results reveal a novel function of Yap in retaining tissue junctions during normal development and after fetal brain injury. PMID:26754915
A Novel Dual Expression Platform for High Throughput Functional Screening of Phage Libraries in Product like Format.

PubMed

Xiao, Xiaodong; Chen, Yan; Mugabe, Sheila; Gao, Changshou; Tkaczyk, Christine; Mazor, Yariv; Pavlik, Peter; Wu, Herren; Dall'Acqua, William; Chowdhury, Partha Sarathi

2015-01-01

High throughput screenings of single chain Fv (scFv) antibody phage display libraries are currently done as soluble scFvs produced in E.coli. Due to endotoxin contaminations from bacterial cells these preparations cannot be reliably used in mammalian cell based assays. The monovalent nature and lack of Fc in soluble scFvs prevent functional assays that are dependent on target cross linking and/or Fc functions. A convenient approach is to convert scFvs into scFv.Fc fusion proteins and express them in mammalian cell lines for screening. This approach is low throughput and is only taken after primary screening of monovalent scFvs that are expressed in bacteria. There is no platform at present that combines the benefits of both bacterial and mammalian expression system for screening phage library output. We have, therefore, developed a novel dual expression vector, called pSplice, which can be used to express scFv.Fc fusion proteins both in E.coli and mammalian cell lines. The hallmark of the vector is an engineered intron which houses the bacterial promoter and signal peptide for expression and secretion of scFv.Fc in E.coli. When the vector is transfected into a mammalian cell line, the intron is efficiently spliced out resulting in a functional operon for expression and secretion of the scFv.Fc fusion protein into the culture medium. By applying basic knowledge of mammalian introns and splisosome, we designed this vector to enable screening of phage libraries in a product like format. Like IgG, the scFv.Fc fusion protein is bi-valent for the antigen and possesses Fc effector functions. Expression in E.coli maintains the speed of the bacterial expression platform and is used to triage clones based on binding and other assays that are not sensitive to endotoxin. Triaged clones are then expressed in a mammalian cell line without the need for any additional cloning steps. Conditioned media from the mammalian cell line containing the fusion proteins are then used for different types of cell based assays. Thus this system retains the speed of the current screening system for phage libraries and adds additional functionality to it.
Compounds that correct F508del-CFTR trafficking can also correct other protein trafficking diseases: an in vitro study using cell lines

PubMed Central

2013-01-01

Background Many genetic diseases are due to defects in protein trafficking where the mutant protein is recognized by the quality control systems, retained in the endoplasmic reticulum (ER), and degraded by the proteasome. In many cases, the mutant protein retains function if it can be trafficked to its proper cellular location. We have identified structurally diverse correctors that restore the trafficking and function of the most common mutation causing cystic fibrosis, F508del-CFTR. Most of these correctors do not act directly as ligands of CFTR, but indirectly on other pathways to promote folding and correction. We hypothesize that these proteostasis regulators may also correct other protein trafficking diseases. Methods To test our hypothesis, we used stable cell lines or transient transfection to express 2 well-studied trafficking disease mutations in each of 3 different proteins: the arginine-vasopressin receptor 2 (AVPR2, also known as V2R), the human ether-a-go-go-related gene (KCNH2, also known as hERG), and finally the sulfonylurea receptor 1 (ABCC8, also known as SUR1). We treated cells expressing these mutant proteins with 9 structurally diverse F508del-CFTR correctors that function through different cellular mechanisms and assessed whether correction occurred via immunoblotting and functional assays. Results were deemed significantly different from controls by a one-way ANOVA (p < 0.05). Results Here we show that F508del-CFTR correctors RDR1, KM60 and KM57 also correct some mutant alleles of other protein trafficking diseases. We also show that one corrector, the cardiac glycoside ouabain, was found to alter the glycosylation of all mutant alleles tested. Conclusions Correctors of F508del-CFTR trafficking might have broader applications to other protein trafficking diseases. PMID:23316740
Contextual extracellular cues promote tumor cell EMT and metastasis by regulating miR-200 family expression

PubMed Central

Gibbons, Don L.; Lin, Wei; Creighton, Chad J.; Rizvi, Zain H.; Gregory, Philip A.; Goodall, Gregory J.; Thilaganathan, Nishan; Du, Liqin; Zhang, Yiqun; Pertsemlidis, Alexander; Kurie, Jonathan M.

2009-01-01

Metastatic disease is a primary cause of cancer-related death, and factors governing tumor cell metastasis have not been fully elucidated. Here, we address this question by using tumor cell lines derived from mice that develop metastatic lung adenocarcinoma owing to expression of mutant K-ras and p53. Despite having widespread somatic genetic alterations, the metastasis-prone tumor cells retained a marked plasticity. They transited reversibly between epithelial and mesenchymal states, forming highly polarized epithelial spheres in three-dimensional culture that underwent epithelial-to-mesenchymal transition (EMT) following treatment with transforming growth factor-β or injection into syngeneic mice. This transition was entirely dependent on the microRNA (miR)-200 family, which decreased during EMT. Forced expression of miR-200 abrogated the capacity of these tumor cells to undergo EMT, invade, and metastasize, and conferred transcriptional features of metastasis-incompetent tumor cells. We conclude that tumor cell metastasis is regulated by miR-200 expression, which changes in response to contextual extracellular cues. PMID:19759262
pH-responsive, gluconeogenic renal epithelial LLC-PK1-FBPase+cells: a versatile in vitro model to study renal proximal tubule metabolism and function

PubMed Central

Curthoys, Norman P.

2014-01-01

Ammoniagenesis and gluconeogenesis are prominent metabolic features of the renal proximal convoluted tubule that contribute to maintenance of systemic acid-base homeostasis. Molecular analysis of the mechanisms that mediate the coordinate regulation of the two pathways required development of a cell line that recapitulates these features in vitro. By adapting porcine renal epithelial LLC-PK1 cells to essentially glucose-free medium, a gluconeogenic subline, termed LLC-PK1-FBPase+ cells, was isolated. LLC-PK1-FBPase+ cells grow in the absence of hexoses and pentoses and exhibit enhanced oxidative metabolism and increased levels of phosphate-dependent glutaminase. The cells also express significant levels of the key gluconeogenic enzymes, fructose-1,6-bisphosphatase (FBPase) and phosphoenolpyruvate carboxykinase (PEPCK). Thus the altered phenotype of LLC-PK1-FBPase+ cells is pleiotropic. Most importantly, when transferred to medium that mimics a pronounced metabolic acidosis (9 mM HCO3−, pH 6.9), the LLC-PK1-FBPase+ cells exhibit a gradual increase in NH4+ ion production, accompanied by increases in glutaminase and cytosolic PEPCK mRNA levels and proteins. Therefore, the LLC-PK1-FBPase+ cells retained in culture many of the metabolic pathways and pH-responsive adaptations characteristic of renal proximal tubules. The molecular mechanisms that mediate enhanced expression of the glutaminase and PEPCK in LLC-PK1-FBPase+ cells have been extensively reviewed. The present review describes novel properties of this unique cell line and summarizes the molecular mechanisms that have been defined more recently using LLC-PK1-FBPase+ cells to model the renal proximal tubule. It also identifies future studies that could be performed using these cells. PMID:24808535
T-cell receptor signaling activates an ITK/NF-κB/GATA-3 axis in T-cell lymphomas facilitating resistance to chemotherapy

PubMed Central

Wang, Tianjiao; Lu, Ye; Polk, Avery; Chowdhury, Pinki; Zamalloa, Carlos Murga; Fujiwara, Hiroshi; Suemori, Koichiro; Beyersdorf, Niklas; Hristov, Alexandra C.; Lim, Megan S.; Bailey, Nathanael G.; Wilcox, Ryan A.

2016-01-01

Purpose T-cell lymphomas are a molecularly heterogeneous group of non-Hodgkin lymphomas (NHL) that account for a disproportionate number of NHL disease-related deaths due to their inherent and acquired resistance to standard multiagent chemotherapy regimens. Despite their molecular heterogeneity and frequent loss of various T-cell specific receptors, the T-cell antigen receptor is retained in the majority of these lymphomas. As T-cell receptor (TCR) engagement activates a number of signaling pathways and transcription factors that regulate T-cell growth and survival, we examined the TCR’s role in mediating resistance to chemotherapy. Experimental Design Genetic and pharmacologic strategies were utilized to determine the contribution of tyrosine kinases and transcription factors activated in conventional T cells following T-cell receptor (TCR) engagement in acquired chemotherapy resistance in primary T-cell lymphoma cells and patient-derived cell lines. Results Here we report that TCR signaling activates a signaling axis that includes ITK, NF-κB, and GATA-3, and promotes chemotherapy resistance. Conclusions These observations have significant therapeutic implications, as pharmacologic inhibition of ITK prevented activation of this signaling axis and overcame chemotherapy resistance. PMID:27780854
Conditionally immortal ovarian cell lines for investigating the influence of ovarian stroma on the estrogen sensitivity and tumorigenicity of ovarian surface epithelial cells.

PubMed

Jiang, Feng; Saunders, Beatriz O; Haller, Edward; Livingston, Sandra; Nicosia, Santo V; Bai, Wenlong

2003-01-01

The tendency of the ovarian surface epithelium (OSE) to undergo metaplastic and morphogenetic changes during the life cycle, at variance with the adjacent peritoneal mesothelial cells, suggests that its biology may be regulated by underlying ovarian stromal cues. However, little is known about the role that the ovarian stroma plays in the pathobiology of the OSE, largely because of the lack of a suitable in vitro model. Here, we describe the establishment and characterization of conditionally immortalized ovarian stromal and surface epithelial cell lines from H-2K(b)-tsA58 transgenic mice that carry the thermolabile mutant of SV-40 large T antigen under the control of an interferon-gamma (IFN-gamma)-inducible promoter. These cells express functional T antigens, grow continuously under permissive conditions at 33 degrees C in the presence of IFN-gamma, and stop dividing when the activity and expression of the tumor antigen is suppressed by restrictive conditions without IFN-gamma at 39 degrees C. Morphological, immunohistochemical, and ultrastructural analyses show that conditionally immortal OSE cells form cobblestone-like monolayers, express cytokeratin and vimentin, contain several microvilli, and develop tight junctions, whereas stromal cells are spindle-like, express vimentin but not cytokeratin, and contain rare microvilli, thus exhibiting epithelial and stromal phenotypes, respectively. At variance with the reported behavior of rat epithelial cells, conditionally immortal mouse epithelial cells are not spontaneously transformed after continuous culture in vitro. More importantly, conditioned media from stromal cells cultured under permissive conditions increase the specific activity of the endogenous estrogen receptor in BG-1 human ovarian epithelial cancer cells and promote these cells' anchorage-independent growth, suggesting the paracrine influence of a stromal factor. In addition, stromal cells cultured under restrictive conditions retain this growth-stimulatory activity, which, therefore, appears to be independent of T antigen expression. These established cell lines should provide a useful in vitro model system for studying the role of cellular interactions in OSE cell growth and tumorigenesis.

Derivation of new human embryonic stem cell lines reveals rapid epigenetic progression in vitro that can be prevented by chemical modification of chromatin

PubMed Central

Diaz Perez, Silvia V.; Kim, Rachel; Li, Ziwei; Marquez, Victor E.; Patel, Sanjeet; Plath, Kathrin; Clark, Amander T.

2012-01-01

Human embryonic stem cells (hESCs) are pluripotent cell types derived from the inner cell mass of human blastocysts. Recent data indicate that the majority of established female XX hESC lines have undergone X chromosome inactivation (XCI) prior to differentiation, and XCI of hESCs can be either XIST-dependent (class II) or XIST-independent (class III). XCI of female hESCs precludes the use of XX hESCs as a cell-based model for examining mechanisms of XCI, and will be a challenge for studying X-linked diseases unless strategies are developed to reactivate the inactive X. In order to recover nuclei with two active X chromosomes (class I), we developed a reprogramming strategy by supplementing hESC media with the small molecules sodium butyrate and 3-deazaneplanocin A (DZNep). Our data demonstrate that successful reprogramming can occur from the XIST-dependent class II nuclear state but not class III nuclear state. To determine whether these small molecules prevent XCI, we derived six new hESC lines under normoxic conditions (UCLA1–UCLA6). We show that class I nuclei are present within the first 20 passages of hESC derivation prior to cryopreservation, and that supplementation with either sodium butyrate or DZNep preserve class I nuclei in the self-renewing state. Together, our data demonstrate that self-renewal and survival of class I nuclei are compatible with normoxic hESC derivation, and that chemical supplementation after derivation provides a strategy to prevent epigenetic progression and retain nuclei with two active X chromosomes in the self-renewing state. PMID:22058289
Inhibition of human immunodeficiency virus type 1 replication by SDZ NIM 811, a nonimmunosuppressive cyclosporine analog.

PubMed Central

Rosenwirth, B; Billich, A; Datema, R; Donatsch, P; Hammerschmid, F; Harrison, R; Hiestand, P; Jaksche, H; Mayer, P; Peichl, P

1994-01-01

(Me-Ile-4)cyclosporin (SDZ NIM 811) is a 4-substituted cyclosporin which is devoid of immunosuppressive activity but retains full capacity for binding to cyclophilin and exhibits potent anti-human immunodeficiency virus type 1 (HIV-1) activity. SDZ NIM 811 selectively inhibits HIV-1 replication in T4 lymphocyte cell lines, in a monocytic cell line, and in HeLa T4 cells. Furthermore, its antiviral activity against laboratory strains and against clinical isolates from geographically distinct regions in primary T4 lymphocytes and in primary monocytes (50% inhibitory concentration = 0.011 to 0.057 micrograms/ml) was demonstrated. SDZ NIM 811 does not inhibit proviral gene expression or virus-specific enzyme functions, either free or bound to cyclophilin. The compound does not influence CD4 expression or inhibit fusion between virus-infected and uninfected cells. SDZ NIM 811 was, however, found to block formation of infectious particles from chronically infected cells. Oral administration to mice, rats, dogs, and monkeys resulted in levels in blood considerably exceeding the drug concentration, which completely blocked virus replication in primary cells. SDZ NIM 811 caused changes of toxicity parameters in rats to a smaller degree than cyclosporine (formerly cyclosporin A). Thus, the potent and selective anti-HIV-1 activity of SDZ NIM 811 and its favorable pharmacokinetic behavior together with its lower nephrotoxicity than that of cyclosporine make this compound a promising candidate for development as an anti-HIV drug. PMID:7527198
Inhibition of human immunodeficiency virus type 1 replication by SDZ NIM 811, a nonimmunosuppressive cyclosporine analog.

PubMed

Rosenwirth, B; Billich, A; Datema, R; Donatsch, P; Hammerschmid, F; Harrison, R; Hiestand, P; Jaksche, H; Mayer, P; Peichl, P

1994-08-01

(Me-Ile-4)cyclosporin (SDZ NIM 811) is a 4-substituted cyclosporin which is devoid of immunosuppressive activity but retains full capacity for binding to cyclophilin and exhibits potent anti-human immunodeficiency virus type 1 (HIV-1) activity. SDZ NIM 811 selectively inhibits HIV-1 replication in T4 lymphocyte cell lines, in a monocytic cell line, and in HeLa T4 cells. Furthermore, its antiviral activity against laboratory strains and against clinical isolates from geographically distinct regions in primary T4 lymphocytes and in primary monocytes (50% inhibitory concentration = 0.011 to 0.057 micrograms/ml) was demonstrated. SDZ NIM 811 does not inhibit proviral gene expression or virus-specific enzyme functions, either free or bound to cyclophilin. The compound does not influence CD4 expression or inhibit fusion between virus-infected and uninfected cells. SDZ NIM 811 was, however, found to block formation of infectious particles from chronically infected cells. Oral administration to mice, rats, dogs, and monkeys resulted in levels in blood considerably exceeding the drug concentration, which completely blocked virus replication in primary cells. SDZ NIM 811 caused changes of toxicity parameters in rats to a smaller degree than cyclosporine (formerly cyclosporin A). Thus, the potent and selective anti-HIV-1 activity of SDZ NIM 811 and its favorable pharmacokinetic behavior together with its lower nephrotoxicity than that of cyclosporine make this compound a promising candidate for development as an anti-HIV drug.
Soluble forms of the cell adhesion molecule L1 produced by insect and baculovirus-transduced mammalian cells enhance Schwann cell motility.

PubMed

Lavdas, Alexandros A; Efrose, Rodica; Douris, Vassilis; Gaitanou, Maria; Papastefanaki, Florentia; Swevers, Luc; Thomaidou, Dimitra; Iatrou, Kostas; Matsas, Rebecca

2010-12-01

For biotechnological applications, insect cell lines are primarily known as hosts for the baculovirus expression system that is capable to direct synthesis of high levels of recombinant proteins through use of powerful viral promoters. Here, we demonstrate the implementation of two alternative approaches based on the baculovirus system for production of a mammalian recombinant glycoprotein, comprising the extracellular part of the cell adhesion molecule L1, with potential important therapeutic applications in nervous system repair. In the first approach, the extracellular part of L1 bearing a myc tag is produced in permanently transformed insect cell lines and purified by affinity chromatography. In the second approach, recombinant baculoviruses that express L1-Fc chimeric protein, derived from fusion of the extracellular part of L1 with the Fc part of human IgG1, under the control of a mammalian promoter are used to infect mammalian HEK293 and primary Schwann cells. Both the extracellular part of L1 bearing a myc tag accumulating in the supernatants of insect cultures as well as L1-Fc secreted by transduced HEK293 or Schwann cells are capable of increasing the motility of Schwann cells with similar efficiency in a gap bridging bioassay. In addition, baculovirus-transduced Schwann cells show enhanced motility when grafted on organotypic cultures of neonatal brain slices while they retain their ability to myelinate CNS axons. This proof-of-concept that the migratory properties of myelin-forming cells can be modulated by recombinant protein produced in insect culture as well as by means of baculovirus-mediated adhesion molecule expression in mammalian cells may have beneficial applications in the field of CNS therapies. ©2010 The Authors. Journal of Neurochemistry © 2010 International Society for Neurochemistry.
Generation of an immortalized mesenchymal stem cell line producing a secreted biosensor protein for glucose monitoring

PubMed Central

Weisman, Itamar; Romano, Jacob; Ivics, Zoltán; Izsvák, Zsuzsanna; Barkai, Uriel

2017-01-01

Diabetes is a chronic disease characterized by high levels of blood glucose. Diabetic patients should normalize these levels in order to avoid short and long term clinical complications. Presently, blood glucose monitoring is dependent on frequent finger pricking and enzyme based systems that analyze the drawn blood. Continuous blood glucose monitors are already on market but suffer from technical problems, inaccuracy and short operation time. A novel approach for continuous glucose monitoring is the development of implantable cell-based biosensors that emit light signals corresponding to glucose concentrations. Such devices use genetically modified cells expressing chimeric genes with glucose binding properties. MSCs are good candidates as carrier cells, as they can be genetically engineered and expanded into large numbers. They also possess immunomodulatory properties that, by reducing local inflammation, may assist long operation time. Here, we generated a novel immortalized human MSC line co-expressing hTERT and a secreted glucose biosensor transgene using the Sleeping Beauty transposon technology. Genetically modified hMSCs retained their mesenchymal characteristics. Stable transgene expression was validated biochemically. Increased activity of hTERT was accompanied by elevated and constant level of stem cell pluripotency markers and subsequently, by MSC immortalization. Furthermore, these cells efficiently suppressed PBMC proliferation in MLR transwell assays, indicating that they possess immunomodulatory properties. Finally, biosensor protein produced by MSCs was used to quantify glucose in cell-free assays. Our results indicate that our immortalized MSCs are suitable for measuring glucose concentrations in a physiological range. Thus, they are appropriate for incorporation into a cell-based, immune-privileged, glucose-monitoring medical device. PMID:28949988
Generation of an immortalized mesenchymal stem cell line producing a secreted biosensor protein for glucose monitoring.

PubMed

Siska, Evangelia K; Weisman, Itamar; Romano, Jacob; Ivics, Zoltán; Izsvák, Zsuzsanna; Barkai, Uriel; Petrakis, Spyros; Koliakos, George

2017-01-01

Diabetes is a chronic disease characterized by high levels of blood glucose. Diabetic patients should normalize these levels in order to avoid short and long term clinical complications. Presently, blood glucose monitoring is dependent on frequent finger pricking and enzyme based systems that analyze the drawn blood. Continuous blood glucose monitors are already on market but suffer from technical problems, inaccuracy and short operation time. A novel approach for continuous glucose monitoring is the development of implantable cell-based biosensors that emit light signals corresponding to glucose concentrations. Such devices use genetically modified cells expressing chimeric genes with glucose binding properties. MSCs are good candidates as carrier cells, as they can be genetically engineered and expanded into large numbers. They also possess immunomodulatory properties that, by reducing local inflammation, may assist long operation time. Here, we generated a novel immortalized human MSC line co-expressing hTERT and a secreted glucose biosensor transgene using the Sleeping Beauty transposon technology. Genetically modified hMSCs retained their mesenchymal characteristics. Stable transgene expression was validated biochemically. Increased activity of hTERT was accompanied by elevated and constant level of stem cell pluripotency markers and subsequently, by MSC immortalization. Furthermore, these cells efficiently suppressed PBMC proliferation in MLR transwell assays, indicating that they possess immunomodulatory properties. Finally, biosensor protein produced by MSCs was used to quantify glucose in cell-free assays. Our results indicate that our immortalized MSCs are suitable for measuring glucose concentrations in a physiological range. Thus, they are appropriate for incorporation into a cell-based, immune-privileged, glucose-monitoring medical device.
Keeping the Best: A Practical Guide to Retaining Key Employees.

ERIC Educational Resources Information Center

Bevan, Stephen; Barber, Linda; Robinson, Dilys

This book, which is intended to assist human resource professionals and line managers in the United Kingdom, is a practical guide to retaining key employees. Discussed in the introduction are the relationship between downsizing and retention, problems that retention difficulties pose for human resource management, and the effects of retention…
Trypanosoma brucei (UMP synthase null mutants) are avirulent in mice, but recover virulence upon prolonged culture in vitro while retaining pyrimidine auxotrophy.

PubMed

Ong, Han B; Sienkiewicz, Natasha; Wyllie, Susan; Patterson, Stephen; Fairlamb, Alan H

2013-10-01

African trypanosomes are capable of both de novo synthesis and salvage of pyrimidines. The last two steps in de novo synthesis are catalysed by UMP synthase (UMPS) - a bifunctional enzyme comprising orotate phosphoribosyl transferase (OPRT) and orotidine monophosphate decarboxylase (OMPDC). To investigate the essentiality of pyrimidine biosynthesis in Trypanosoma brucei, we generated a umps double knockout (DKO) line by gene replacement. The DKO was unable to grow in pyrimidine-depleted medium in vitro, unless supplemented with uracil, uridine, deoxyuridine or UMP. DKO parasites were completely resistant to 5-fluoroorotate and hypersensitive to 5-fluorouracil, consistent with loss of UMPS, but remained sensitive to pyrazofurin indicating that, unlike mammalian cells, the primary target of pyrazofurin is not OMPDC. The null mutant was unable to infect mice indicating that salvage of host pyrimidines is insufficient to support growth. However, following prolonged culture in vitro, parasites regained virulence in mice despite retaining pyrimidine auxotrophy. Unlike the wild-type, both pyrimidine auxotrophs secreted substantial quantities of orotate, significantly higher in the virulent DKO line. We propose that this may be responsible for the recovery of virulence in mice, due to host metabolism converting orotate to uridine, thereby bypassing the loss of UMPS in the parasite. © 2013 The Authors. Molecular Microbiology published by John Wiley & Sons Ltd.
Endocytic function is critical for influenza A virus infection via DC-SIGN and L-SIGN

PubMed Central

Gillespie, Leah; Roosendahl, Paula; Ng, Wy Ching; Brooks, Andrew G.; Reading, Patrick C.; Londrigan, Sarah L.

2016-01-01

The ubiquitous presence of cell-surface sialic acid (SIA) has complicated efforts to identify specific transmembrane glycoproteins that function as bone fide entry receptors for influenza A virus (IAV) infection. The C-type lectin receptors (CLRs) DC-SIGN (CD209) and L-SIGN (CD209L) enhance IAV infection however it is not known if they act as attachment factors, passing virions to other unknown receptors for virus entry, or as authentic entry receptors for CLR-mediated virus uptake and infection. Sialic acid-deficient Lec2 Chinese Hamster Ovary (CHO) cell lines were resistant to IAV infection whereas expression of DC-SIGN/L-SIGN restored susceptibility of Lec2 cells to pH- and dynamin-dependent infection. Moreover, Lec2 cells expressing endocytosis-defective DC-SIGN/L-SIGN retained capacity to bind IAV but showed reduced susceptibility to infection. These studies confirm that DC-SIGN and L-SIGN are authentic endocytic receptors for IAV entry and infection. PMID:26763587
A687V EZH2 is a driver of histone H3 lysine 27 (H3K27) hypertrimethylation.

PubMed

Ott, Heidi M; Graves, Alan P; Pappalardi, Melissa B; Huddleston, Michael; Halsey, Wendy S; Hughes, Ashley M; Groy, Arthur; Dul, Edward; Jiang, Yong; Bai, Yuchen; Annan, Roland; Verma, Sharad K; Knight, Steven D; Kruger, Ryan G; Dhanak, Dashyant; Schwartz, Benjamin; Tummino, Peter J; Creasy, Caretha L; McCabe, Michael T

2014-12-01

The EZH2 methyltransferase silences gene expression through methylation of histone H3 on lysine 27 (H3K27). Recently, EZH2 mutations have been reported at Y641, A677, and A687 in non-Hodgkin lymphoma. Although the Y641F/N/S/H/C and A677G mutations exhibit clearly increased activity with substrates dimethylated at lysine 27 (H3K27me2), the A687V mutant has been shown to prefer a monomethylated lysine 27 (H3K27me1) with little gain of activity toward H3K27me2. Herein, we demonstrate that despite this unique substrate preference, A687V EZH2 still drives increased H3K27me3 when transiently expressed in cells. However, unlike the previously described mutants that dramatically deplete global H3K27me2 levels, A687V EZH2 retains normal levels of H3K27me2. Sequencing of B-cell-derived cancer cell lines identified an acute lymphoblastic leukemia cell line harboring this mutation. Similar to exogenous expression of A687V EZH2, this cell line exhibited elevated H3K27me3 while possessing H3K27me2 levels higher than Y641- or A677-mutant lines. Treatment of A687V EZH2-mutant cells with GSK126, a selective EZH2 inhibitor, was associated with a global decrease in H3K27me3, robust gene activation, caspase activation, and decreased proliferation. Structural modeling of the A687V EZH2 active site suggests that the increased catalytic activity with H3K27me1 may be due to a weakened interaction with an active site water molecule that must be displaced for dimethylation to occur. These findings suggest that A687V EZH2 likely increases global H3K27me3 indirectly through increased catalytic activity with H3K27me1 and cells harboring this mutation are highly dependent on EZH2 activity for their survival. ©2014 American Association for Cancer Research.
On-Line Course Development: Engaging and Retaining Students

ERIC Educational Resources Information Center

Bruster, Benita G.

2015-01-01

As the number of on-line classes and the demand for on-line education continues to sky-rocket, it is critical that course developers and university faculty have the skills to effectively design curricula, to develop engaging learning opportunities, and to create responsive courses that meet individual student needs. This paper details three…
Hybrid mimics and hybrid vigor in Arabidopsis

PubMed Central

Wang, Li; Greaves, Ian K.; Groszmann, Michael; Wu, Li Min; Dennis, Elizabeth S.; Peacock, W. James

2015-01-01

F1 hybrids can outperform their parents in yield and vegetative biomass, features of hybrid vigor that form the basis of the hybrid seed industry. The yield advantage of the F1 is lost in the F2 and subsequent generations. In Arabidopsis, from F2 plants that have a F1-like phenotype, we have by recurrent selection produced pure breeding F5/F6 lines, hybrid mimics, in which the characteristics of the F1 hybrid are stabilized. These hybrid mimic lines, like the F1 hybrid, have larger leaves than the parent plant, and the leaves have increased photosynthetic cell numbers, and in some lines, increased size of cells, suggesting an increased supply of photosynthate. A comparison of the differentially expressed genes in the F1 hybrid with those of eight hybrid mimic lines identified metabolic pathways altered in both; these pathways include down-regulation of defense response pathways and altered abiotic response pathways. F6 hybrid mimic lines are mostly homozygous at each locus in the genome and yet retain the large F1-like phenotype. Many alleles in the F6 plants, when they are homozygous, have expression levels different to the level in the parent. We consider this altered expression to be a consequence of transregulation of genes from one parent by genes from the other parent. Transregulation could also arise from epigenetic modifications in the F1. The pure breeding hybrid mimics have been valuable in probing the mechanisms of hybrid vigor and may also prove to be useful hybrid vigor equivalents in agriculture. PMID:26283378
Synthesis and evaluation of 1-amino-6-halo-β-carbolines as antimalarial and antiprion agents.

PubMed

Thompson, Mark J; Louth, Jennifer C; Little, Susan M; Jackson, Matthew P; Boursereau, Yohan; Chen, Beining; Coldham, Iain

2012-04-01

Malaria is one of the world's most devastating parasitic diseases, causing almost one million deaths each year. Growing resistance to classical antimalarial drugs, such as chloroquine, necessitates the discovery of new therapeutic agents for successful control of this global disease. Here, we report the synthesis of some 6-halo-β-carbolines as analogues of the potent antimalarial natural product, manzamine A, retaining its heteroaromatic core whilst providing compounds with much improved synthetic accessibility. Two compounds displayed superior activity to chloroquine itself against a resistant Plasmodium falciparum strain, identifying them as promising leads for future development. Furthermore, in line with previous reports of similarities in antimalarial and antiprion effects of aminoaryl-based antimalarial agents, the 1-amino-β-carboline libraries were also found to possess significant bioactivity against a prion-infected cell line. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Superresolved digital in-line holographic microscopy for high-resolution lensless biological imaging

NASA Astrophysics Data System (ADS)

Micó, Vicente; Zalevsky, Zeev

2010-07-01

Digital in-line holographic microscopy (DIHM) is a modern approach capable of achieving micron-range lateral and depth resolutions in three-dimensional imaging. DIHM in combination with numerical imaging reconstruction uses an extremely simplified setup while retaining the advantages provided by holography with enhanced capabilities derived from algorithmic digital processing. We introduce superresolved DIHM incoming from time and angular multiplexing of the sample spatial frequency information and yielding in the generation of a synthetic aperture (SA). The SA expands the cutoff frequency of the imaging system, allowing submicron resolutions in both transversal and axial directions. The proposed approach can be applied when imaging essentially transparent (low-concentration dilutions) and static (slow dynamics) samples. Validation of the method for both a synthetic object (U.S. Air Force resolution test) to quantify the resolution improvement and a biological specimen (sperm cells biosample) are reported showing the generation of high synthetic numerical aperture values working without lenses.
A novel p53 mutational hotspot in skin tumors from UV-irradiated Xpc mutant mice alters transactivation functions.

PubMed

Inga, Alberto; Nahari, Dorit; Velasco-Miguel, Susana; Friedberg, Errol C; Resnick, Michael A

2002-08-22

A mutation in codon 122 of the mouse p53 gene resulting in a T to L amino acid substitution (T122-->L) is frequently associated with skin cancer in UV-irradiated mice that are both homozygous mutant for the nucleotide excision repair (NER) gene Xpc (Xpc(-/-)) and hemizygous mutant for the p53 gene. We investigated the functional consequences of the mouse T122-->L mutation when expressed either in mammalian cells or in the yeast Saccharomyces cerevisiae. Similar to a non-functional allele, high expression of the T122-->L allele in p53(-/-) mouse embryo fibroblasts and human Saos-2 cells failed to suppress growth. However, the T122-->L mutant p53 showed wild-type transactivation levels with Bax and MDM2 promoters when expressed in either cell type and retained transactivation of the p21 and the c-Fos promoters in one cell line. Using a recently developed rheostatable p53 induction system in yeast we assessed the T122-->L transactivation capacity at low levels of protein expression using 12 different p53 response elements (REs). Compared to wild-type p53 the T122-->L protein manifested an unusual transactivation pattern comprising reduced and enhanced activity with specific REs. The high incidence of the T122-->L mutant allele in the Xpc(-/-) background suggests that both genetic and epigenetic conditions may facilitate the emergence of particular functional p53 mutations. Furthermore, the approach that we have taken also provides for the dissection of functions that may be retained in many p53 tumor alleles.
Mitigation of Quantum Dot Cytotoxicity by Microencapsulation

PubMed Central

Romoser, Amelia; Ritter, Dustin; Majitha, Ravish; Meissner, Kenith E.; McShane, Michael; Sayes, Christie M.

2011-01-01

When CdSe/ZnS-polyethyleneimine (PEI) quantum dots (QDs) are microencapsulated in polymeric microcapsules, human fibroblasts are protected from acute cytotoxic effects. Differences in cellular morphology, uptake, and viability were assessed after treatment with either microencapsulated or unencapsulated dots. Specifically, QDs contained in microcapsules terminated with polyethylene glycol (PEG) mitigate contact with and uptake by cells, thus providing a tool to retain particle luminescence for applications such as extracellular sensing and imaging. The microcapsule serves as the “first line of defense” for containing the QDs. This enables the individual QD coating to be designed primarily to enhance the function of the biosensor. PMID:21814567
Coordinated encoding between cell types in the retina: insights from the theory of phase transitions

NASA Astrophysics Data System (ADS)

Sharpee, Tatyana

2015-03-01

In this talk I will describe how the emergence of some types of neurons in the brain can be quantitatively described by the theory of transitions between different phases of matter. The two key parameters that control the separation of neurons into subclasses are the mean and standard deviation of noise levels among neurons in the population. The mean noise level plays the role of temperature in the classic theory of phase transitions, whereas the standard deviation is equivalent to pressure, in the case of liquid-gas transitions, or to magnetic field for magnetic transitions. Our results account for properties of two recently discovered types of salamander OFF retinal ganglion cells, as well as the absence of multiple types of ON cells. We further show that, across visual stimulus contrasts, retinal circuits continued to operate near the critical point whose quantitative characteristics matched those expected near a liquid-gas critical point and described by the nearest-neighbor Ising model in three dimensions. Because the retina needs to operate under changing stimulus conditions, the observed parameters of cell types corresponded to metastable states in the region between the spinodal line and the line describing maximally informative solutions. Such properties of neural circuits can maximize information transmission in a given environment while retaining the ability to quickly adapt to a new environment. NSF CAREER award 1254123 and NIH R01EY019493
Effect of Gsk3 inhibitor CHIR99021 on aneuploidy levels in rat embryonic stem cells.

PubMed

Bock, Anagha S; Leigh, Nathan D; Bryda, Elizabeth C

2014-06-01

Germline competent embryonic stem (ES) cells can serve as a tool to create genetically engineered rat strains used to elucidate gene function or provide disease models. In optimum culture conditions, ES cells are able to retain their pluripotent state. The type of components present and their concentration in ES cell culture media greatly influences characteristics of ES cells including the ability to maintain the cells in a pluripotent state. We routinely use 2i media containing inhibitors CHIR99021 and PD0325901 to culture rat ES cells. CHIR99021 specifically inhibits the Gsk3β pathway. We have found that the vendor source of CHIR99021 has a measurable influence on the level of aneuploidy seen over time as rat ES cells are passaged. Karyotyping of three different rat ES cell lines passaged multiple times showed increased aneuploidy when CHIR99021 from source B was used. Mass spectrometry analysis of this inhibitor showed the presence of unexpected synthetic small molecules, which might directly or indirectly cause increases in chromosome instability. Identifying these molecules could further understanding of their influence on chromosome stability and indicate how to improve synthesis of this media component to prevent deleterious effects in culture.
Cytosolic T3-binding protein modulates dynamic alteration of T3-mediated gene expression in cells.

PubMed

Takeshige, Keiko; Sekido, Takashi; Kitahara, Jun-ichirou; Ohkubo, Yousuke; Hiwatashi, Dai; Ishii, Hiroaki; Nishio, Shin-ichi; Takeda, Teiji; Komatsu, Mitsuhisa; Suzuki, Satoru

2014-01-01

μ-Crystallin (CRYM) is also known as NADPH-dependent cytosolic T3-binding protein. A study using CRYM-null mice suggested that CRYM stores triiodothyronine (T3) in tissues. We previously established CRYM-expressing cells derived from parental GH3 cells. To examine the precise regulation of T3-responsive genes in the presence of CRYM, we evaluated serial alterations of T3-responsive gene expression by changing pericellular T3 concentrations in the media. We estimated the constitutive expression of three T3-responsive genes, growth hormone (GH), deiodinase 1 (Dio1), and deiodinase 2 (Dio2), in two cell lines. Subsequently, we measured the responsiveness of these three genes at 4, 8, 16, and 24 h after adding various concentrations of T3. We also estimated the levels of these mRNAs 24 and 48 h after removing T3. The levels of constitutive expression of GH and Dio1 were low and high in C8 cells, respectively, while Dio2 expression was not significantly different between GH3 and C8 cells. When treated with T3, Dio2 expression was significantly enhanced in C8 cells, while there were no differences in GH or Dio1 expression between GH3 and C8 cell lines. In contrast, removal of T3 retained the mRNA expression of GH and Dio2 in C8 cells. These results suggest that CRYM expression increases and sustains the T3 responsiveness of genes in cells, especially with alteration of the pericellular T3 concentration. The heterogeneity of T3-related gene expression is dependent on cellular CRYM expression in cases of dynamic changes in pericellular T3 concentration.
Altered chromosome 6 in immortal human fibroblasts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hubbard-Smith, K.; Pardinas, J.R.; Jha, K.K.

1992-05-01

Human diploid fibroblasts have a limited life span in vitro, and spontaneous immortalization is an extremely rare event. We have used transformation of human diploid fibroblasts by an origin-defective simian virus 40 genome to develop series of genetically matched immortal cell lines to analyze immortalization. Comparison of a preimmortal transformant (SVtsA/HF-A) with its uncloned and cloned immortalized derivatives (AR5 and HAL) has failed to reveal any major alteration involving the simian virus 40 genome. Karyotypic analysis, however, demonstrated that all of the immortal cell lines in this series have alterations of chromosome 6 involving loss of the portion distal tomore » 6q21. The karyotypic analysis was corroborated by DNA analyses. Southern analysis demonstrated that only one copy of three proto-oncogene loci (ros1, c-myb, and mas1) on 6q was retained in immortal cells. Polymerase chain reaction analysis of the microsatellite polymorphism at 6q22 (D6S87) showed loss of heterozygosity. In addition, elevated expression of c-myb (6q22-23) was observed. We hypothesize that the region at and/or distal to 6q21 plays a role in immortalization, consistent with the presence of a growth suppressor gene. 66 refs., 6 figs., 2 tabs.« less

Cellular Analysis of Adult Neural Stem Cells for Investigating Prion Biology.

PubMed

Haigh, Cathryn L

2017-01-01

Traditional primary and secondary cell cultures have been used for the investigation of prion biology and disease for many years. While both types of cultures produce highly valid and immensely valuable results, they also have their limitations; traditional cell lines are often derived from cancers, therefore subject to numerous DNA changes, and primary cultures are labor-intensive and expensive to produce requiring sacrifice of many animals. Neural stem cell (NSC) cultures are a relatively new technology to be used for the study of prion biology and disease. While NSCs are subject to their own limitations-they are generally cultured ex vivo in environments that artificially force their growth-they also have their own unique advantages. NSCs retain the ability for self-renewal and can therefore be propagated in culture similarly to secondary cultures without genetic manipulation. In addition, NSCs are multipotent; they can be induced to differentiate into mature cells of central nervous system (CNS) linage. The combination of self-renewal and multipotency allows NSCs to be used as a primary cell line over multiple generations saving time, costs, and animal harvests, thus providing a valuable addition to the existing cell culture repertoire used for investigation of prion biology and disease. Furthermore, NSC cultures can be generated from mice of any genotype, either by embryonic harvest or harvest from adult brain, allowing gene expression to be studied without further genetic manipulation. This chapter describes a standard method of culturing adult NSCs and assays for monitoring NSC growth, migration, and differentiation and revisits basic reactive oxygen species detection in the context of NSC cultures.
trans-Golgi retention of a plasma membrane protein: mutations in the cytoplasmic domain of the asialoglycoprotein receptor subunit H1 result in trans-Golgi retention

PubMed Central

1995-01-01

Unlike the wild-type asialoglycoprotein receptor subunit H1 which is transported to the cell surface, endocytosed and recycled, a mutant lacking residues 4-33 of the 40-amino acid cytoplasmic domain was found to be retained intracellularly upon expression in different cell lines. The mutant protein accumulated in the trans-Golgi, as judged from the acquisition of trans-Golgi-specific modifications of the protein and from the immunofluorescence staining pattern. It was localized to juxtanuclear, tubular structures that were also stained by antibodies against galactosyltransferase and gamma-adaptin. The results of further mutagenesis in the cytoplasmic domain indicated that the size rather than the specific sequence of the cytoplasmic domain determines whether H1 is retained in the trans-Golgi or transported to the cell surface. Truncation to less than 17 residues resulted in retention, and extension of a truncated tail by an unrelated sequence restored surface transport. The transmembrane segment of H1 was not sufficient for retention of a reporter molecule and it could be replaced by an artificial apolar sequence without affecting Golgi localization. The cytoplasmic domain thus appears to inhibit interaction(s) of the exoplasmic portion of H1 with trans-Golgi component(s) for example by steric hindrance or by changing the positioning of the protein in the membrane. This mechanism may also be functional in other proteins. PMID:7615632
Deletion of the Vaccinia Virus I2 Protein Interrupts Virion Morphogenesis, Leading to Retention of the Scaffold Protein and Mislocalization of Membrane-Associated Entry Proteins

PubMed Central

Hyun, Seong-In; Weisberg, Andrea

2017-01-01

ABSTRACT The I2L open reading frame of vaccinia virus (VACV) encodes a conserved 72-amino-acid protein with a putative C-terminal transmembrane domain. Previous studies with a tetracycline-inducible mutant demonstrated that I2-deficient virions are defective in cell entry. The purpose of the present study was to determine the step of replication or entry that is affected by loss of the I2 protein. Fluorescence microscopy experiments showed that I2 colocalized with a major membrane protein of immature and mature virions. We generated a cell line that constitutively expressed I2 and allowed construction of the VACV I2L deletion mutant vΔI2. As anticipated, vΔI2 was unable to replicate in cells that did not express I2. Unexpectedly, morphogenesis was interrupted at a stage after immature virion formation, resulting in the accumulation of dense spherical particles instead of brick-shaped mature virions with well-defined core structures. The abnormal particles retained the D13 scaffold protein of immature virions, were severely deficient in the transmembrane proteins that comprise the entry fusion complex (EFC), and had increased amounts of unprocessed membrane and core proteins. Total lysates of cells infected with vΔI2 also had diminished EFC proteins due to instability attributed to their hydrophobicity and failure to be inserted into viral membranes. A similar instability of EFC proteins had previously been found with unrelated mutants blocked earlier in morphogenesis that also accumulated viral membranes retaining the D13 scaffold. We concluded that I2 is required for virion morphogenesis, release of the D13 scaffold, and the association of EFC proteins with viral membranes. IMPORTANCE Poxviruses comprise a large family that infect vertebrates and invertebrates, cause disease in both in humans and in wild and domesticated animals, and are being engineered as vectors for vaccines and cancer therapy. In addition, investigations of poxviruses have provided insights into many aspects of cell biology. The I2 protein is conserved in all poxviruses that infect vertebrates, suggesting an important role. The present study revealed that this protein is essential for vaccinia virus morphogenesis and that its absence results in an accumulation of deformed virus particles retaining the scaffold protein and deficient in surface proteins needed for cell entry. PMID:28490596
Proteasome inhibition with bortezomib induces cell death in GBM stem-like cells and temozolomide-resistant glioma cell lines, but stimulates GBM stem-like cells' VEGF production and angiogenesis.

PubMed

Bota, Daniela A; Alexandru, Daniela; Keir, Stephen T; Bigner, Darell; Vredenburgh, James; Friedman, Henry S

2013-12-01

Recurrent malignant gliomas have inherent resistance to traditional chemotherapy. Novel therapies target specific molecular mechanisms involved in abnormal signaling and resistance to apoptosis. The proteasome is a key regulator of multiple cellular functions, and its inhibition in malignant astrocytic lines causes cell growth arrest and apoptotic cell death. The proteasome inhibitor bortezomib was reported to have very good in vitro activity against malignant glioma cell lines, with modest activity in animal models as well as in clinical trials as a single agent. In this paper, the authors describe the multiple effects of bortezomib in both in vitro and in vivo glioma models and offer a novel explanation for its seeming lack of activity. Glioma stem-like cells (GSCs) were obtained from resected glioblastomas (GBMs) at surgery and expanded in culture. Stable glioma cell lines (U21 and D54) as well as temozolomide (TMZ)-resistant glioma cells derived from U251 and D54-MG were also cultured. GSCs from 2 different tumors, as well as D54 and U251 cells, were treated with bortezomib, and the effect of the drug was measured using an XTT cell viability assay. The activity of bortezomib was then determined in D54-MG and/or U251 cells using apoptosis analysis as well as caspase-3 activity and proteasome activity measurements. Human glioma xenograft models were created in nude mice by subcutaneous injection. Bevacizumab was administered via intraperitoneal injection at a dose of 5 mg/kg daily. Bortezomib was administered by intraperitoneal injection 1 hour after bevacizumab administration in doses of at a dose of 0.35 mg/kg on days 1, 4, 8, and 11 every 21 days. Tumors were measured twice weekly. Bortezomib induced caspase-3 activation and apoptotic cell death in stable glioma cell lines and in glioma stem-like cells (GSCs) derived from malignant tumor specimens Furthermore, TMZ-resistant glioma cell lines retained susceptibility to the proteasome inhibition. The bortezomib activity was directly proportional with the cells' baseline proteasome activity. The proteasome inhibition stimulated both hypoxia-inducible factor (HIF)-1α and vascular endothelial growth factor (VEGF) production in malignant GSCs. As such, the VEGF produced by GSCs stimulated endothelial cell growth, an effect that could be prevented by the addition of bevacizumab (VEGF antibody) to the media. Similarly, administration of bortezomib and bevacizumab to athymic mice carrying subcutaneous malignant glioma xenografts resulted in greater tumor inhibition and greater improvement in survival than administration of either drug alone. These data indicate that simultaneous proteasome inhibition and VEGF blockade offer increased benefit as a strategy for malignant glioma therapy. The results of this study indicate that combination therapies based on bortezomib and bevacizumab might offer an increased benefit when the two agents are used in combination. These drugs have a complementary mechanism of action and therefore can be used together to treat TMZ-resistant malignant gliomas.
Phenotype and Functional Features of Human Telomerase Reverse Transcriptase Immortalized Human Airway Smooth Muscle Cells from Asthmatic and Non-Asthmatic Donors.

PubMed

Burgess, J K; Ketheson, A; Faiz, A; Limbert Rempel, K A; Oliver, B G; Ward, J P T; Halayko, A J

2018-01-16

Asthma is an obstructive respiratory disease characterised by chronic inflammation with airway hyperresponsiveness. In asthmatic airways, there is an increase in airway smooth muscle (ASM) cell bulk, which differs from non-asthmatic ASM in characteristics. This study aimed to assess the usefulness of hTERT immortalisation of human ASM cells as a research tool. Specifically we compared proliferative capacity, inflammatory mediator release and extracellular matrix (ECM) production in hTERT immortalised and parent primary ASM cells from asthmatic and non-asthmatic donors. Our studies revealed no significant differences in proliferation, IL-6 and eotaxin-1 production, or CTGF synthesis between donor-matched parent and hTERT immortalised ASM cell lines. However, deposition of ECM proteins fibronectin and fibulin-1 was significantly lower in immortalised ASM cells compared to corresponding primary cells. Notably, previously reported differences in proliferation and inflammatory mediator release between asthmatic and non-asthmatic ASM cells were retained, but excessive ECM protein deposition in asthmatic ASM cells was lost in hTERT ASM cells. This study shows that hTERT immortalised ASM cells mirror primary ASM cells in proliferation and inflammatory profile characteristics. Moreover, we demonstrate both strengths and weaknesses of this immortalised cell model as a representation of primary ASM cells for future asthma pathophysiological research.
Experimental and Analytical Investigation of Pressure Differentials for Clean and Loaded Wire Meshes Used in Zeolite Retention

NASA Technical Reports Server (NTRS)

Knox, James C.

2004-01-01

Following failure of the carbon dioxide removal assembly (CDRA) on the ISS, a CDRA teardown, test, and evaluation (TT&E) effort found that the sorbent material was not retained as intended by the packed beds and that presence of the sorbent in the check valve and selector valve was the cause of the failure of these components. This paper documents the development of design data for an in-line filter element. The purpose of the in-line filter is to provide temporary protection for on-orbit CDRA hardware until the bed retainment system can be redesigned and replaced.
Off-line data reduction

NASA Astrophysics Data System (ADS)

Gutowski, Marek W.

1992-12-01

Presented is a novel, heuristic algorithm, based on fuzzy set theory, allowing for significant off-line data reduction. Given the equidistant data, the algorithm discards some points while retaining others with their original values. The fraction of original data points retained is typically {1}/{6} of the initial value. The reduced data set preserves all the essential features of the input curve. It is possible to reconstruct the original information to high degree of precision by means of natural cubic splines, rational cubic splines or even linear interpolation. Main fields of application should be non-linear data fitting (substantial savings in CPU time) and graphics (storage space savings).
Tissue-specific programming of memory CD8 T cell subsets impacts protection against lethal respiratory virus infection

PubMed Central

Tahiliani, Vikas

2016-01-01

How tissue-specific anatomical distribution and phenotypic specialization are linked to protective efficacy of memory T cells against reinfection is unclear. Here, we show that lung environmental cues program recently recruited central-like memory cells with migratory potentials for their tissue-specific functions during lethal respiratory virus infection. After entering the lung, some central-like cells retain their original CD27hiCXCR3hi phenotype, enabling them to localize near the infected bronchiolar epithelium and airway lumen to function as the first line of defense against pathogen encounter. Others, in response to local cytokine triggers, undergo a secondary program of differentiation that leads to the loss of CXCR3, migration arrest, and clustering within peribronchoarterial areas and in interalveolar septa. Here, the immune system adapts its response to prevent systemic viral dissemination and mortality. These results reveal the striking and unexpected spatial organization of central- versus effector-like memory cells within the lung and how cooperation between these two subsets contributes to host defense. PMID:27879287
A bioaccumulative cyclometalated platinum(II) complex with two-photon-induced emission for live cell imaging.

PubMed

Koo, Chi-Kin; Wong, Ka-Leung; Man, Cornelia Wing-Yin; Lam, Yun-Wah; So, Leo King-Yan; Tam, Hoi-Lam; Tsao, Sai-Wah; Cheah, Kok-Wai; Lau, Kai-Chung; Yang, Yang-Yi; Chen, Jin-Can; Lam, Michael Hon-Wah

2009-02-02

The cyclometalated platinum(II) complex [Pt(L)Cl], where HL is a new cyclometalating ligand 2-phenyl-6-(1H-pyrazol-3-yl)pyridine containing C(phenyl), N(pyridyl), and N(pyrazolyl) donor moieties, was found to possess two-photon-induced luminescent properties. The two-photon-absorption cross section of the complex in N,N-dimethylformamide at room temperature was measured to be 20.8 GM. Upon two-photon excitation at 730 nm from a Ti:sapphire laser, bright-green emission was observed. Besides its two-photon-induced luminescent properties, [Pt(L)Cl] was able to be rapidly accumulated in live HeLa and NIH3T3 cells. The two-photon-induced luminescence of the complex was retained after live cell internalization and can be observed by two-photon confocal microscopy. Its bioaccumulation properties enabled time-lapse imaging of the internalization process of the dye into living cells. Cytotoxicity of [Pt(L)Cl] to both tested cell lines was low, according to MTT assays, even at loadings as high as 20 times the dose concentration for imaging for 6 h.
Cell-wall deficient L. monocytogenes L-forms feature abrogated pathogenicity

PubMed Central

Schnell, Barbara; Staubli, Titu; Harris, Nicola L.; Rogler, Gerhard; Kopf, Manfred; Loessner, Martin J.; Schuppler, Markus

2014-01-01

Stable L-forms are cell wall-deficient bacteria which are able to multiply and propagate indefinitely, despite the absence of a rigid peptidoglycan cell wall. We investigated whether L-forms of the intracellular pathogen L. monocytogenes possibly retain pathogenicity, and if they could trigger an innate immune response. While phagocytosis of L. monocytogenes L-forms by non-activated macrophages sometimes resulted in an unexpected persistence of the bacteria in the phagocytes, they were effectively eliminated by IFN-γ preactivated or bone marrow-derived macrophages (BMM). These findings were in line with the observed down-regulation of virulence factors in the cell-wall deficient L. monocytogenes. Absence of Interferon-β (IFN-β) triggering indicated inability of L-forms to escape from the phagosome into the cytosol. Moreover, abrogated cytokine response in MyD88-deficient dendritic cells (DC) challenged with L. monocytogenes L-forms suggested an exclusive TLR-dependent host response. Taken together, our data demonstrate a strong attenuation of Listeria monocytogenes L-form pathogenicity, due to diminished expression of virulence factors and innate immunity recognition, eventually resulting in elimination of L-form bacteria from phagocytes. PMID:24904838
Properties of Cells Carrying the Herpes Simplex Virus Type 2 Thymidine Kinase Gene: Mechanisms of Reversion to a Thymidine Kinase-Negative Phenotype

PubMed Central

Bastow, K. F.; Darby, G.; Wildy, P.; Minson, A. C.

1980-01-01

We have isolated cells with a thymidine kinase-negative (tk−) phenotype from cells which carry the herpes simplex virus type 2 tk gene by selection in 5-bromodeoxyuridine or 9-(2-hydroxyethoxymethyl)guanine. Both selection routines generated revertants with a frequency of 10−3 to 10−4, and resistance to either compound conferred simultaneous resistance to the other. tk− revertants fell into three classes: (i) cells that arose by deletion of all virus sequences, (ii) cells that had lost the virus tk gene but retained a nonselected virus-specific function and arose by deletion of part of the virus-specific sequence, and (iii) cells that retained the potential to express all of the virus-specific functions of the parental cells and retained all of the virus-specific DNA sequences. Images PMID:16789205
Method and an apparatus to control the lateral motion of a long metal bar being formed by a mechanical process such as rolling or drawing

DOEpatents

Chang, Tzyy-Shuh; Huang, Hsun-Hau; Lin, Chang-Hung

2007-10-02

An adjustable guide, includes two or more mechanisms each having a rotatable retaining element containing a retaining groove with a variable radius in its perimeter surface. The grooves form a guidance path to control the lateral, i.e. non-axial, motion of a long bar moving along a longitudinal axis during a production process.The diameter of the guidance path varies according to the variable radii of the grooves. The guidance path increases in size at a predetermined rate, from a point of origin to an end point on the retaining groove. Rotating the retaining elements causes the diameter of the retaining grooves to change so that the size of the guidance path can be changed to match the diameter of the bar being rolled, size of the guidance path can be changed to fit the diameter of a new bar rolled without having to exchange the guide for a different sized guide, reduce fiction between the bar and the guide, a media, such as compressed air, can be injected between the retaining elements via orifices.Each retaining element is attached to a mounting apparatus. The mounting apparatus can be fixed or flexible. The flexible mounting apparatus includes one or more springs and one or more shock absorbers. A force neutral position of the flexible mounting apparatus is designed to be located on the predetermined ideal bar path line. The flexible mounting apparatus dissipates kinetic energy from the bar thereby reducing the bar's lateral motion relative to the ideal bar path line.The damping ratio of the mounting apparatus can be adjustable to alter the product's vibration mode to enable better control of the bar's lateral motion.
High-level production and purification in a functional state of an extrasynaptic gamma-aminobutyric acid type A receptor containing α4β3δ subunits.

PubMed

Zhou, Xiaojuan; Desai, Rooma; Zhang, Yinghui; Stec, Wojciech J; Miller, Keith W; Jounaidi, Youssef

2018-01-01

The inhibitory γ-aminobutyric acid type A receptors are implicated in numerous physiological processes, including cognition and inhibition of neurotransmission, rendering them important molecular targets for many classes of drugs. Functionally, the entire GABAAR family of receptors can be subdivided into phasic, fast acting synaptic receptors, composed of α-, β- and γ-subunits, and tonic extrasynaptic receptors, many of which contain the δ-subunit in addition to α- and β-subunits. Whereas the subunit arrangement of the former group is agreed upon, that of the αβδ GABAARs remains unresolved by electrophysiological and pharmacological research. To resolve such issues will require biophysical techniques that demand quantities of receptor that have been previously unavailable. Therefore, we have engineered a stable cell line with tetracycline inducible expression of human α4-, β3- and N-terminally Flag-tagged δ-subunits. This cell line achieved a specific activity between 15 and 20 pmol [3H]muscimol sites/mg of membrane protein, making it possible to obtain 1 nmole of purified α4β3δ GABAAR from sixty 15-cm culture dishes. When induced, these cells exhibited agonist-induced currents with characteristics comparable to those previously reported for this receptor and a pharmacology that included strong modulation by etomidate and the δ-subunit-specific ligand, DS2. Immunoaffinity purification and reconstitution in CHAPS/asolectin micelles resulted in the retention of equilibrium allosteric interactions between the separate agonist, anesthetic and DS2 sites. Moreover, all three subunits retained glycosylation. The establishment of this well-characterized cell line will allow molecular level studies of tonic receptors to be undertaken.
Identification of epithelial label-retaining cells at the transition between the anal canal and the rectum in mice

PubMed Central

Runck, Laura A; Kramer, Megan; Ciraolo, Georgianne; Lewis, Alfor G

2010-01-01

In certain regions of the body, transition zones exist where stratified squamous epithelia directly abut against other types of epithelia. Certain transition zones are especially prone to tumorigenesis an example being the anorectal junction, although the reason for this is not known. One possibility is that the abrupt transition of the simple columnar epithelium of the colon to the stratified squamous epithelium of the proximal portion of the anal canal may contain a unique stem cell niche. We investigated whether the anorectal region contained cells with stem cell properties relative to the adjacent epithelium. We utilized a tetracycline-regulatable histone H2B-GFP transgenic mice model, previously used to identify hair follicle stem cells, to fluorescently label slow-cycling anal epithelial cells (e.g., prospective stem cells) in combination with a panel of putative stem cell markers. We identified a population of long-term GFP label-retaining cells concentrated at the junction between the anal canal and the rectum. These cells are BrdU-retaining cells and expressed the stem cell marker CD34. Moreover, tracking the fate of the anal label-retaining cells in vivo revealed that the slow-cycling cells only gave rise to progeny of the anal epithelium. In conclusion, we identified a unique population of cells at the anorectal junction which can be separated from the other basal anal epithelial cells based upon the expression of the stem cell marker CD34 and integrin α6, and thus represent a putative anal stem cell population. PMID:20647777
Tumor-Initiating Label-Retaining Cancer Cells in Human Gastrointestinal Cancers Undergo Asymmetric Cell Division

PubMed Central

Xin, Hong-Wu; Hari, Danielle M.; Mullinax, John E.; Ambe, Chenwi M.; Koizumi, Tomotake; Ray, Satyajit; Anderson, Andrew J.; Wiegand, Gordon W.; Garfield, Susan H.; Thorgeirsson, Snorri S.; Avital, Itzhak

2012-01-01

Label-retaining cells (LRCs) have been proposed to represent adult tissue stem cells. LRCs are hypothesized to result from either slow cycling or asymmetric cell division (ACD). However, the stem cell nature and whether LRC undergo ACD remain controversial. Here, we demonstrate label-retaining cancer cells (LRCCs) in several gastrointestinal (GI) cancers including fresh surgical specimens. Using a novel method for isolation of live LRCC, we demonstrate that a subpopulation of LRCC is actively dividing and exhibits stem cells and pluripotency gene expression profiles. Using real-time confocal microscopic cinematography, we show live LRCC undergoing asymmetric nonrandom chromosomal cosegregation LRC division. Importantly, LRCCs have greater tumor-initiating capacity than non-LRCCs. Based on our data and that cancers develop in tissues that harbor normal-LRC, we propose that LRCC might represent a novel population of GI stem-like cancer cells. LRCC may provide novel mechanistic insights into the biology of cancer and regenerative medicine and present novel targets for cancer treatment. PMID:22331764
Silane-modified surfaces in specific antibody-mediated cell recognition.

PubMed

Sterzynska, Karolina; Budna, Joanna; Frydrych-Tomczak, Emilia; Hreczycho, Grzegorz; Malinska, Agnieszka; Maciejewski, Hieronim; Zabel, Maciej

2014-01-01

The immobilization of antibodies on various surfaces has been the subject of advanced research in various immunoassay-based diagnostic devices. The physical and chemical stabilities of the immobilized antibodies on a solid surface still cause many problems because upon immobilizing antibody molecules, the antigen-binding ability usually decreases. The silanization of surfaces with organosilanes carrying chemically active groups such as (3-aminopropyl) triethoxysilane (APTES) can accommodate these antigen-binding molecules in an appropriate orientation so that their functionality and binding activity are essentially retained. In this study, n-butyltrimethoxysilane (BMS) and 3-(octafluoropentyloxy)-propyltriethoxysilane (OFPOS) were used as "blocking silanes". The aims of this study were to compare the effectiveness of specific antibody binding of APTES, APTES + BMS and APTES + OFPOS and to characterize the modified surfaces by contact angle measurements and immunofluorescence measurements prior to and after immobilizing proteins. Additionally, we have evaluated the functionality of the immobilized antibodies by their abilities to bind EpCAM-positive human colon adenocarcinoma cell line (LoVo) and EpCAM-negative mouse embryonic fibroblast cell line (3T3). Cell enumeration was conducted on the basis of DAPI-positive signals and recorded using a confocal laser scanning biological microscope. The results of our study showed that the immobilization capability and reactivity of APTES, APTES + BMS and APTES + OFPOS differ. The modification of APTES with unreactive silanes (BMS,OFPOS) is recommended to improve the antibody binding efficiency. However, using OFPOS resulted in more effective antibody and cell binding, and it appears to be the most useful compound in specific antibody-mediated cell recognition.
Generation of gene-targeted mice using embryonic stem cells derived from a transgenic mouse model of Alzheimer's disease.

PubMed

Yamamoto, Satoshi; Ooshima, Yuki; Nakata, Mitsugu; Yano, Takashi; Matsuoka, Kunio; Watanabe, Sayuri; Maeda, Ryouta; Takahashi, Hideki; Takeyama, Michiyasu; Matsumoto, Yoshio; Hashimoto, Tadatoshi

2013-06-01

Gene-targeting technology using mouse embryonic stem (ES) cells has become the "gold standard" for analyzing gene functions and producing disease models. Recently, genetically modified mice with multiple mutations have increasingly been produced to study the interaction between proteins and polygenic diseases. However, introduction of an additional mutation into mice already harboring several mutations by conventional natural crossbreeding is an extremely time- and labor-intensive process. Moreover, to do so in mice with a complex genetic background, several years may be required if the genetic background is to be retained. Establishing ES cells from multiple-mutant mice, or disease-model mice with a complex genetic background, would offer a possible solution. Here, we report the establishment and characterization of novel ES cell lines from a mouse model of Alzheimer's disease (3xTg-AD mouse, Oddo et al. in Neuron 39:409-421, 2003) harboring 3 mutated genes (APPswe, TauP301L, and PS1M146V) and a complex genetic background. Thirty blastocysts were cultured and 15 stable ES cell lines (male: 11; female: 4) obtained. By injecting these ES cells into diploid or tetraploid blastocysts, we generated germline-competent chimeras. Subsequently, we confirmed that F1 mice derived from these animals showed similar biochemical and behavioral characteristics to the original 3xTg-AD mice. Furthermore, we introduced a gene-targeting vector into the ES cells and successfully obtained gene-targeted ES cells, which were then used to generate knockout mice for the targeted gene. These results suggest that the present methodology is effective for introducing an additional mutation into mice already harboring multiple mutated genes and/or a complex genetic background.
Cytotoxic effect of indigenously fabricated dental magnets for application in prosthodontics.

PubMed

Guttal, Satyabodh Shesharaj; Nadiger, Ramesh K; Shetty, Pravinkumar

2018-01-01

Dental magnets are used for retaining removable prostheses such as a removable partial denture, complete denture, and maxillofacial prosthesis. They provide good retention for the prostheses. However, the elements released from the magnets may be cytotoxic for the tissues. Therefore, it is necessary to evaluate their cytotoxic effect on cell lines. The aim of the study is to check the cytotoxic effect of indigenously fabricated dental magnets on animal cell lines. Neodymium-iron-boron (Nd-Fe-B) magnet was tested for cytotoxicity. The magnet was encased in a teflon cylinder. Magnets were placed in the well tissue-cultured plates together with a suspension containing NIH 3T3 mouse fibroblasts (5 × 10 5 cells/ml). After 3 days of incubation at 37°C, cell viability was determined by mean transit time (MTT) assay. Cells were subsequently dissolved in 100 μl dimethyl sulfoxide with gentle shaking for 2 h at room temperature followed by measurement of absorbance at 570 nm. Eight replicate wells were used at each point in each of four separate measurements. Measured absorbance values were directly used for calculating percent of viable cells remaining after the respective treatment. Data were analyzed statistically with significance level set at P < 0.05. The control group had highest absorbance reading for the MTT assay followed by test group. The lowest values were found with bare Nd-Fe-B magnets. One-way ANOVA test was performed for the data obtained. There was a statistical significant difference seen in the positive control (bare magnets, 44.96) and the test (teflon cased magnets, 96.90) group. More number of viable cells was visible in test group cells indicating that the indigenously fabricated dental magnet did not show any cytotoxicity.
EMMPRIN/CD147-encriched membrane vesicles released from malignant human testicular germ cells increase MMP production through tumor-stroma interaction.

PubMed

Milia-Argeiti, Eleni; Mourah, Samia; Vallée, Benoit; Huet, Eric; Karamanos, Nikos K; Theocharis, Achilleas D; Menashi, Suzanne

2014-08-01

Elevated levels of EMMPRIN/CD147 in cancer tissues have been correlated with tumor progression but the regulation of its expression is not yet understood. Here, the regulation of EMMPRIN expression was investigated in testicular germ cell tumor (TGCTs) cell lines. EMMPRIN expression in seminoma JKT-1 and embryonal carcinoma NT2/D1 cell lines was determined by Western blot, immunofluorescence and qRT-PCR. Membrane vesicles (MVs) secreted from these cells, treated or not with EMMPRIN siRNA, were isolated by differential centrifugations of their conditioned medium. MMP-2 was analyzed by zymography and qRT-PCR. The more aggressive embryonic carcinoma NT2/D1 cells expressed more EMMPRIN mRNA than the seminoma JKT-1 cells, but surprisingly contained less EMMPRIN protein, as determined by immunoblotting and immunostaining. The protein/mRNA discrepancy was not due to accelerated protein degradation in NT2/D1 cells, but by the secretion of EMMPRIN within MVs, as the vesicles released from NT2/D1 contained considerably more EMMPRIN than those released from JKT-1. EMMPRIN-containing MVs obtained from NT2/D1, but not from EMMPRIN-siRNA treated NT2/D1, increased MMP-2 production in fibroblasts to a greater extent than those from JKT-1 cells. The data presented show that the more aggressive embryonic carcinoma cells synthesize more EMMPRIN than seminoma cells, but which they preferentially target to secreted MVs, unlike seminoma cells which retain EMMPRIN within the cell membrane. This cellular event points to a mechanism by which EMMPRIN expressed by malignant testicular cells can exert its MMP inducing effect on distant cells within the tumor microenvironment to promote tumor invasion. This article is part of a Special Issue entitled Matrix-mediated cell behaviour and properties. Copyright © 2014 Elsevier B.V. All rights reserved.
The metabolism of testosterone by dermal papilla cells cultured from human pubic and axillary hair follicles concurs with hair growth in 5 alpha-reductase deficiency.

PubMed

Hamada, K; Thornton, M J; Laing, I; Messenger, A G; Randall, V A

1996-05-01

Androgens regulate the growth of many human hair follicles, but only pubic, axillary, and scalp hair growth occur in men with 5 alpha-reductase deficiency. This suggests that 5 alpha-dihydrotestosterone is the active intracellular androgen in androgen-dependent follicles, except in the axilla and pubis. Since the dermal papilla plays a major regulatory role in hair follicles and may be the site of androgen action, we have investigated androgen metabolism in six primary lines of cultured dermal papilla cells from pubic and axillary hair follicles; previous studies have shown that beard cells take up and metabolize testosterone, retaining and secreting 5 alpha-dihydrotestosterone. After 24 h preincubation in serum-free Eagle's medium 199, 100-mm dishes of confluent cells were incubated for 2 h with 5 nM [1,2,6,7-3H]testosterone. Media were collected and the cells washed with phosphate-buffered saline and extracted with chloroform: methanol (2:1). After the addition of unlabeled and 14C-labeled marker steroids, the extracts were analyzed by a two-step thin-layer chromatography system; steroid identity was confirmed by recrystallization to a constant 3H/14C ratio. Beard and pubic dermal papilla cells were also incubated for 24 h, and the medium was analyzed at various times. The results from pubic and axillary primary cell lines were similar. In both cells and media the major steroid identified was testosterone, but significant amounts of androstenedione were present, indicating 17 beta-hydroxysteroid dehydrogenase activity; androstenedione was also identified within the cells, but a small amount of 5 alpha-dihydrotestosterone was only identified in one pubic cell line. Beard dermal papilla cells secreted large amounts of 5 alpha-dihydrotestosterone into the medium over 24 h in contrast to pubic cells, which produced only very small amounts. The pubic and axillary cell results contrasts with the observations of pronounced 5 alpha-dihydrotestosterone in beard cells and confirm that androgen metabolism in cultured dermal papilla cells reflects the parent follicle's ability to respond to androgen in the absence of 5 alpha-reductase type II in vivo. This supports our hypothesis that androgen acts on hair follicles via the dermal papilla and suggests that cultured dermal papilla cells may offer an important model system for studies of androgen action.

T-cell Receptor Signaling Activates an ITK/NF-κB/GATA-3 axis in T-cell Lymphomas Facilitating Resistance to Chemotherapy.

PubMed

Wang, Tianjiao; Lu, Ye; Polk, Avery; Chowdhury, Pinki; Zamalloa, Carlos Murga; Fujiwara, Hiroshi; Suemori, Koichiro; Beyersdorf, Niklas; Hristov, Alexandra C; Lim, Megan S; Bailey, Nathanael G; Wilcox, Ryan A

2017-05-15

Purpose: T-cell lymphomas are a molecularly heterogeneous group of non-Hodgkin lymphomas (NHL) that account for a disproportionate number of NHL disease-related deaths due to their inherent and acquired resistance to standard multiagent chemotherapy regimens. Despite their molecular heterogeneity and frequent loss of various T cell-specific receptors, the T-cell antigen receptor is retained in the majority of these lymphomas. As T-cell receptor (TCR) engagement activates a number of signaling pathways and transcription factors that regulate T-cell growth and survival, we examined the TCR's role in mediating resistance to chemotherapy. Experimental Design: Genetic and pharmacologic strategies were utilized to determine the contribution of tyrosine kinases and transcription factors activated in conventional T cells following TCR engagement in acquired chemotherapy resistance in primary T-cell lymphoma cells and patient-derived cell lines. Results: Here, we report that TCR signaling activates a signaling axis that includes ITK, NF-κB, and GATA-3 and promotes chemotherapy resistance. Conclusions: These observations have significant therapeutic implications, as pharmacologic inhibition of ITK prevented the activation of this signaling axis and overcame chemotherapy resistance. Clin Cancer Res; 23(10); 2506-15. ©2016 AACR . ©2016 American Association for Cancer Research.
Insect GDNF:TTC fusion protein improves delivery of GDNF to mouse CNS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Jianhong; Chian, Ru-Ju; Ay, Ilknur

2009-12-18

With a view toward improving delivery of exogenous glial cell line-derived neurotrophic factor (GDNF) to CNS motor neurons in vivo, we evaluated the bioavailability and pharmacological activity of a recombinant GDNF:tetanus toxin C-fragment fusion protein in mouse CNS. Following intramuscular injection, GDNF:TTC but not recombinant GDNF (rGDNF) produced strong GDNF immunostaining within ventral horn cells of the spinal cord. Intrathecal infusion of GDNF:TTC resulted in tissue concentrations of GDNF in lumbar spinal cord that were at least 150-fold higher than those in mice treated with rGDNF. While levels of immunoreactive choline acetyltransferase and GFR{alpha}-1 in lumbar cord were not alteredmore » significantly by intrathecal infusion of rGNDF, GDNF:TTC, or TTC, only rGDNF and GDNF:TTC caused significant weight loss following intracerebroventricular infusion. These studies indicate that insect cell-derived GDNF:TTC retains its bi-functional activity in mammalian CNS in vivo and improves delivery of GDNF to spinal cord following intramuscular- or intrathecal administration.« less
Internalization and intracellular retention of CD4 are two separate functions of the human immunodeficiency virus type 1 Nef protein.

PubMed

Giolo, Giorgia; Neri, Francesca; Casartelli, Nicoletta; Potestà, Marina; Belleudi, Francesca; Torrisi, Maria Rosaria; Doria, Margherita

2007-11-01

The pathogenic Nef protein of the human immunodeficiency virus type 1 (HIV-1) downregulates CD4 by inducing its endocytosis and by inhibiting the transport of the receptor to the cell membrane. By means of in vivo-selected mutations, we show that L37, P78 and E177 residues of Nef are required for its effect on CD4 internalization and recycling but dispensable for Nef-induced retention and degradation of intracellular CD4. Of note, the function of Nef on the anterograde transport of newly synthesized CD4 molecules is irrelevant in cells with a slow constitutive CD4 turnover such as T cell lines. Moreover, we show that a mutated CD4 that is unresponsive to Nef-mediated endocytosis, CD4LL(144)AA, is retained intracellularly and degraded by Nef like wild-type CD4. Thus, Nef's abilities to enhance endocytosis and induce intracellular retention of CD4 are mediated by separate protein surfaces and occur through distinct mechanisms.
AMTEC powered residential furnace and auxiliary power

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ivanenok, J.F. III; Sievers, R.K.

1996-12-31

Residential gas furnaces normally rely on utility grid electric power to operate the fans and/or the pumps used to circulate conditioned air or water and they are thus vulnerable to interruptions of utility grid service. Experience has shown that such interruptions can occur during the heating season, and can lead to serious consequences. A gas furnace coupled to an AMTEC conversion system retains the potential to produce heat and electricity (gas lines are seldom interrupted during power outages), and can save approximately $47/heating season compared to a conventional gas furnace. The key to designing a power system is understanding, andmore » predicting, the cell performance characteristics. The three main processes that must be understood and modeled to fully characterize an AMTEC cell are the electro-chemical, sodium vapor flow, and heat transfer. This paper will show the results of the most recent attempt to model the heat transfer in a multi-tube AMTEC cell and then discusses the conceptual design of a self-powered residential furnace.« less
Mycobacterium-Host Cell Relationships in Granulomatous Lesions in a Mouse Model of Latent Tuberculous Infection

PubMed Central

2015-01-01

Tuberculosis (TB) is a dangerous infectious disease characterized by a tight interplay between mycobacteria and host cells in granulomatous lesions (granulomas) during the latent, asymptomatic stage of infection. Mycobacterium-host cell relationships were analyzed in granulomas obtained from various organs of BALB/c mice with chronic TB infection caused by in vivo exposure to the Bacillus Calmette-Guérin (BCG) vaccine. Acid-fast BCG-mycobacteria were found to be morphologically and functionally heterogeneous (in size, shape, and replication rates in colonies) in granuloma macrophages, dendritic cells, and multinucleate Langhans giant cells. Cord formation by BCG-mycobacteria in granuloma cells has been observed. Granuloma macrophages retained their ability to ingest damaged lymphocytes and thrombocytes in the phagosomes; however, their ability to destroy BCG-mycobacteria contained in these cells was compromised. No colocalization of BCG-mycobacteria and the LysoTracker dye was observed in the mouse cells. Various relationships between granuloma cells and BCG-mycobacteria were observed in different mice belonging to the same line. Several mice totally eliminated mycobacterial infection. Granulomas in the other mice had mycobacteria actively replicating in cells of different types and forming cords, which is an indicator of mycobacterial virulence and, probably, a marker of the activation of tuberculous infection in animals. PMID:26064970
Mycobacterium-Host Cell Relationships in Granulomatous Lesions in a Mouse Model of Latent Tuberculous Infection.

PubMed

Ufimtseva, Elena

2015-01-01

Tuberculosis (TB) is a dangerous infectious disease characterized by a tight interplay between mycobacteria and host cells in granulomatous lesions (granulomas) during the latent, asymptomatic stage of infection. Mycobacterium-host cell relationships were analyzed in granulomas obtained from various organs of BALB/c mice with chronic TB infection caused by in vivo exposure to the Bacillus Calmette-Guérin (BCG) vaccine. Acid-fast BCG-mycobacteria were found to be morphologically and functionally heterogeneous (in size, shape, and replication rates in colonies) in granuloma macrophages, dendritic cells, and multinucleate Langhans giant cells. Cord formation by BCG-mycobacteria in granuloma cells has been observed. Granuloma macrophages retained their ability to ingest damaged lymphocytes and thrombocytes in the phagosomes; however, their ability to destroy BCG-mycobacteria contained in these cells was compromised. No colocalization of BCG-mycobacteria and the LysoTracker dye was observed in the mouse cells. Various relationships between granuloma cells and BCG-mycobacteria were observed in different mice belonging to the same line. Several mice totally eliminated mycobacterial infection. Granulomas in the other mice had mycobacteria actively replicating in cells of different types and forming cords, which is an indicator of mycobacterial virulence and, probably, a marker of the activation of tuberculous infection in animals.
Design and development of a magnetic device for mesenchymal stem cell retaining in deep targets

NASA Astrophysics Data System (ADS)

Banis, G. C.

2017-12-01

This paper focuses on the retaining of mesenchymal stem cells in blood flow conditions using the appropriate magnetic field. Mesenchymal stem cells can be tagged with magnetic nanoparticles and thus, they can be manipulated from distance, through the application of an external magnetic field. In this paper the case of kidney as target of the therapy is being studied.
Anterior implant-supported overdentures.

PubMed

Ben-Ur, Z; Gorfil, C; Shifman, A

1996-09-01

Retention of complete mandibular dentures can be successfully achieved by means of an implant-retained or natural tooth-retained bar and clip system in the anterior segment of the mandible. The same design principles hold true for both methods of anchoring the retentive bar. These retentive elements must be constructed to allow some freedom of movement around a fulcrum line designed to be perpendicular to the sagittal plane.
The B-Cell Specific Transcription Factor, Oct-2, Promotes Epstein-Barr Virus Latency by Inhibiting the Viral Immediate-Early Protein, BZLF1

PubMed Central

Robinson, Amanda R.; Kwek, Swee Sen; Kenney, Shannon C.

2012-01-01

The Epstein-Barr virus (EBV) latent-lytic switch is mediated by the BZLF1 immediate-early protein. EBV is normally latent in memory B cells, but cellular factors which promote viral latency specifically in B cells have not been identified. In this report, we demonstrate that the B-cell specific transcription factor, Oct-2, inhibits the function of the viral immediate-early protein, BZLF1, and prevents lytic viral reactivation. Co-transfected Oct-2 reduces the ability of BZLF1 to activate lytic gene expression in two different latently infected nasopharyngeal carcinoma cell lines. Furthermore, Oct-2 inhibits BZLF1 activation of lytic EBV promoters in reporter gene assays, and attenuates BZLF1 binding to lytic viral promoters in vivo. Oct-2 interacts directly with BZLF1, and this interaction requires the DNA-binding/dimerization domain of BZLF1 and the POU domain of Oct-2. An Oct-2 mutant (Δ262–302) deficient for interaction with BZLF1 is unable to inhibit BZLF1-mediated lytic reactivation. However, an Oct-2 mutant defective for DNA-binding (Q221A) retains the ability to inhibit BZLF1 transcriptional effects and DNA-binding. Importantly, shRNA-mediated knockdown of endogenous Oct-2 expression in several EBV-positive Burkitt lymphoma and lymphoblastoid cell lines increases the level of lytic EBV gene expression, while decreasing EBNA1 expression. Moreover, treatments which induce EBV lytic reactivation, such as anti-IgG cross-linking and chemical inducers, also decrease the level of Oct-2 protein expression at the transcriptional level. We conclude that Oct-2 potentiates establishment of EBV latency in B cells. PMID:22346751
Rescue of a Porcine Anellovirus (Torque Teno Sus Virus 2) from Cloned Genomic DNA in Pigs

PubMed Central

Huang, Yao-Wei; Patterson, Abby R.; Opriessnig, Tanja; Dryman, Barbara A.; Gallei, Andreas; Harrall, Kylie K.; Vaughn, Eric M.; Roof, Michael B.

2012-01-01

Anelloviruses are a group of single-stranded circular DNA viruses infecting humans and other animal species. Animal models combined with reverse genetic systems of anellovirus have not been developed. We report here the construction and initial characterization of full-length DNA clones of a porcine anellovirus, torque teno sus virus 2 (TTSuV2), in vitro and in vivo. We first demonstrated that five cell lines, including PK-15 cells, are free of TTSuV1 or TTSuV2 contamination, as determined by a real-time PCR and an immunofluorescence assay (IFA) using anti-TTSuV antibodies. Recombinant plasmids harboring monomeric or tandem-dimerized genomic DNA of TTSuV2 from the United States and Germany were constructed. Circular TTSuV2 genomic DNA with or without introduced genetic markers and tandem-dimerized TTSuV2 plasmids were transfected into PK-15 cells, respectively. Splicing of viral mRNAs was identified in transfected cells. Expression of TTSuV2-specific open reading frame 1 (ORF1) in cell nuclei, especially in nucleoli, was detected by IFA. However, evidence of productive TTSuV2 infection was not observed in 12 different cell lines transfected with the TTSuV2 DNA clones. Transfection with circular DNA from a TTSuV2 deletion mutant did not produce ORF1 protein, suggesting that the observed ORF1 expression is driven by TTSuV2 DNA replication in cells. Pigs inoculated with either the tandem-dimerized clones or circular genomic DNA of U.S. TTSuV2 developed viremia, and the introduced genetic markers were retained in viral DNA recovered from the sera of infected pigs. The availability of an infectious DNA clone of TTSuV2 will facilitate future study of porcine anellovirus pathogenesis and biology. PMID:22491450
Effective elimination of liver cancer stem-like cells by CD90 antibody targeted thermosensitive magnetoliposomes

PubMed Central

Yang, Rui; An, Li Y.; Miao, Qin F.; Li, Feng M.; Han, Yong; Wang, Hui X.; Liu, Dang P.; Chen, Rong; Tang, Sha Q.

2016-01-01

Aim To investigate the use of thermosensitive magnetoliposomes (TMs) loaded with magnetic iron oxide (Fe3O4) and the anti-cancer stem cell marker CD90 (CD90@TMs) to target and kill CD90+ liver cancer stem cells (LCSCs). Methods The hepatocellular carcinoma cell line Huh7 was used to separate CD90+ LCSCs by magnetic-activated cell sorting. CD90@TMs was characterized and their ability to target CD90+ LCSCs was determined. Experiments were used to investigate whether CD90@TMs combined with magnetic hyperthermia could effectively eliminate CD90+ LCSCs. Results The present study demonstrated that CD90+ LCSCs with stem cells properties were successfully isolated. We also successfully prepared CD90@TMs that was almost spherical and uniform with an average diameter of 130±4.6 nm and determined that magnetic iron oxide could be incorporated and retained a superparamagnetic response. CD90@TMs showed good targeting and increased inhibition of CD90+ LCSCs in vitro and in vivo compared to TMs. Conclusion CD90@TMs can be used for controlled and targeted delivery of anticancer drugs, which may offer a promising alternative for HCC therapy. PMID:27145285
Small-molecule MDM2 antagonists reveal aberrant p53 signaling in cancer: Implications for therapy

PubMed Central

Tovar, Christian; Rosinski, James; Filipovic, Zoran; Higgins, Brian; Kolinsky, Kenneth; Hilton, Holly; Zhao, Xiaolan; Vu, Binh T.; Qing, Weiguo; Packman, Kathryn; Myklebost, Ola; Heimbrook, David C.; Vassilev, Lyubomir T.

2006-01-01

The p53 tumor suppressor retains its wild-type conformation and transcriptional activity in half of all human tumors, and its activation may offer a therapeutic benefit. However, p53 function could be compromised by defective signaling in the p53 pathway. Using a small-molecule MDM2 antagonist, nutlin-3, to probe downstream p53 signaling we find that the cell-cycle arrest function of the p53 pathway is preserved in multiple tumor-derived cell lines expressing wild-type p53, but many have a reduced ability to undergo p53-dependent apoptosis. Gene array analysis revealed attenuated expression of multiple apoptosis-related genes. Cancer cells with mdm2 gene amplification were most sensitive to nutlin-3 in vitro and in vivo, suggesting that MDM2 overexpression may be the only abnormality in the p53 pathway of these cells. Nutlin-3 also showed good efficacy against tumors with normal MDM2 expression, suggesting that many of the patients with wild-type p53 tumors may benefit from antagonists of the p53–MDM2 interaction. PMID:16443686
Entrapment into nanoemulsions potentiates the anticancer activity of tocotrienols against the highly malignant (+SA) mouse mammary epithelial cells.

PubMed

Alayoubi, Alaadin; Ayoub, Nehad M; Malaviya, Abhita; Sylvester, Paul W; Nazzal, Sami

2014-05-01

The highly malignant +SA mouse mammary epithelial cells were used as the model cell line over the years to establish the anticancer activity of tocotrienols. Tocotrienols, however, have poor oral bioavailability and were therefore entrapped into parenteral nanoemulsions for parenteral administration. The objective of this work was to test whether the activity of tocotrienols in lipid nanoemulsions against the +SA cells was retained. A secondary objective was to test whether stabilizing the nanoemulsions with poloxamer or sodium oleate would affect their activity. Nanoemulsions were found to be significantly more potent than tocotrienol/albumin conjugate. The IC50 values of the poloxamer and sodium oleate nanoemulsions were 3 and 6 microM, respectively, whereas the IC50 value of the conjugate was 10 microM. The antiproliferative activity of the nanoemulsions was also found to inversely correlate with particle size. No activity was observed with nanoemulsions loaded with alpha-tocopherol or vehicle, which confirmed the cytotoxic activity of tocotrienols and the potential use of nanoemulsions in cancer therapy.
AuNP-DG: deoxyglucose-labeled gold nanoparticles as X-ray computed tomography contrast agents for cancer imaging.

PubMed

Aydogan, Bulent; Li, Ji; Rajh, Tijana; Chaudhary, Ahmed; Chmura, Steven J; Pelizzari, Charles; Wietholt, Christian; Kurtoglu, Metin; Redmond, Peter

2010-10-01

To study the feasibility of using 2-deoxy-D-glucose (2-DG)-labeled gold nanoparticle (AuNP-DG) as a computed tomography (CT) contrast agent with tumor targeting capability through in vitro experiments. Gold nanoparticles (AuNP) were fabricated and were conjugated with 2-deoxy-D-glucose. The human alveolar epithelial cancer cell line, A-549, was chosen for the in vitro cellular uptake assay. Two groups of cell samples were incubated with the AuNP-DG and the unlabeled AuNP, respectively. Following the incubation, the cells were washed with sterile PBS to remove the excess gold nanoparticles and spun to cell pellets using a centrifuge. The cell pellets were imaged using a microCT scanner immediately after the centrifugation. The reconstructed CT images were analyzed using a commercial software package. Significant contrast enhancement in the cell samples incubated with the AuNP-DG with respect to the cell samples incubated with the unlabeled AuNP was observed in multiple CT slices. Results from this study demonstrate enhanced uptake of 2-DG-labeled gold nanoparticle by cancer cells in vitro and warrant further experiments to study the exact molecular mechanism by which the AuNP-DG is internalized and retained in the tumor cells.
Microscopic anatomy of the digestive system in normal and regenerating specimens of the brittlestar Amphipholis kochii.

PubMed

Frolova, Lidia T; Dolmatov, Igor Yu

2010-06-01

The morphology and regeneration of the digestive system of the ophiuroid Amphipholis kochii were investigated. The epithelia of the esophagus and stomach of A. kochii were composed of typical enterocytes and mucous cells. The digestive epithelium of the stomach contained two types of granular secretory cells. After autotomy of the disk, the animals retained the esophagus and a small part of the stomach. The dedifferentiation of enterocytes and mucous cells began on the first day after autotomy. On day 3 the cells formed an anlage of stomach around the mouth opening. Later, the stomach anlage grew as a result of cell proliferation. The opening on the aboral side of the body was closed by day 7. By this time differentiating cells were already observed in the stomach lining. The stomach mesothelium was formed by peritoneocytes and myoepithelial cells, which migrated from other coelomic epithelia of the body. Our study showed that the formation of the digestive system in A. kochii during regeneration depended on cells from the esophagus and the stomach remnant. Both enterocytes and mucous cells were able to dedifferentiate, migrate, and proliferate to give rise to the luminal epithelium. The basic mechanism of stomach formation was epithelial morphogenesis.
Isolation and functional interrogation of adult human prostate epithelial stem cells at single cell resolution.

PubMed

Hu, Wen-Yang; Hu, Dan-Ping; Xie, Lishi; Li, Ye; Majumdar, Shyama; Nonn, Larisa; Hu, Hong; Shioda, Toshi; Prins, Gail S

2017-08-01

Using primary cultures of normal human prostate epithelial cells, we developed a novel prostasphere-based, label-retention assay that permits identification and isolation of stem cells at a single cell level. Their bona fide stem cell nature was corroborated using in vitro and in vivo regenerative assays and documentation of symmetric/asymmetric division. Robust WNT10B and KRT13 levels without E-cadherin or KRT14 staining distinguished individual stem cells from daughter progenitors in spheroids. Following FACS to isolate label-retaining stem cells from label-free progenitors, RNA-seq identified unique gene signatures for the separate populations which may serve as useful biomarkers. Knockdown of KRT13 or PRAC1 reduced sphere formation and symmetric self-renewal highlighting their role in stem cell maintenance. Pathways analysis identified ribosome biogenesis and membrane estrogen-receptor signaling enriched in stem cells with NF-ĸB signaling enriched in progenitors; activities that were biologically confirmed. Further, bioassays identified heightened autophagy flux and reduced metabolism in stem cells relative to progenitors. These approaches similarly identified stem-like cells from prostate cancer specimens and prostate, breast and colon cancer cell lines suggesting wide applicability. Together, the present studies isolate and identify unique characteristics of normal human prostate stem cells and uncover processes that maintain stem cell homeostasis in the prostate gland. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
Mapping of four distinct BCR-related loci to chromosome region 22q11: order of BCR loci relative to chronic myelogenous leukemia and acute lymphoblastic leukemia breakpoints

DOE Office of Scientific and Technical Information (OSTI.GOV)

Croce, C.M.; Huebner, K.; Isobe, M.

1987-10-01

A probe derived from the 3' region of the BCR gene (breakpoint cluster region gene) detects four distinct loci in the human genome. One of the loci corresponds to the complete BCR gene, whereas the other contain a 3' segment of the gene. After HindIII cleavage of human DNA, these four loci are detected as 23-, 19-, 13-, and 9-kikobase-pair fragments, designated BCR4, BCR3, BCR2, and BCR1, respectively, with BCR1 deriving from the original complete BCR gene. All four BCR loci segregate 100% concordantly with human chromosome 22 in a rodent-human somatic cell hybrid panel and are located at chromosomemore » region 22q11.2 by chromosomal in situ hybridization. The BCR2 and BCR4 loci are amplified in leukemia cell line K562 cells, indicating that they fall within the amplification unit that includes immunoglobulin lambda light chain locus (IGL) and ABL locus on the K562 Philadelphia chromosome (Ph/sup 1/). Similarly, in mouse-human hybrids retaining a Ph/sup 1/ chromosome derived from an acute lymphoblastic leukemia-in the absence of the 9q/sup +/ and 22, only BCR2 and BCR4 loci are retained. Thus, the order of loci on chromosome 22 is centromere ..-->.. BCR2, BCR4, and IGL ..-->.. BCR1 ..-->.. BCR3 ..-->.. SIS, possibly eliminating BCR2 and BCR4 loci as candidate targets for juxtaposition to the ABL gene in the acute lymphoblastic leukemia Ph/sup 1/ chromosome.« less
Homologous recombination between overlapping thymidine kinase gene fragments stably inserted into a mouse cell genome.

PubMed

Lin, F L; Sternberg, N

1984-05-01

We have constructed a substrate to study homologous recombination between adjacent segments of chromosomal DNA. This substrate, designated lambda tk2 , consists of one completely defective and one partially defective herpes simplex virus thymidine kinase (tk) gene cloned in bacteriophage lambda DNA. The two genes have homologous 984-base-pair sequences and are separated by 3 kilobases of largely vector DNA. When lambda tk2 DNA was transferred into mouse LMtk- cells by the calcium phosphate method, rare TK+ transformants were obtained that contained many (greater than 40) copies of the unrecombined DNA. Tk- revertants, which had lost most of the copies of unrecombined DNA, were isolated from these TK+-transformed lines. Two of these Tk- lines were further studied by analysis of their reversion back to the Tk+ phenotype. They generated ca. 200 Tk+ revertants per 10(8) cells after growth in nonselecting medium for 5 days. All of these Tk+ revertants have an intact tk gene reconstructed by homologous recombination; they also retain various amounts of unrecombined lambda tk2 DNA. Southern blot analysis suggested that at least some of the recombination events involve unequal sister chromatid exchanges. We also tested three agents, mitomycin C, 12-O-tetradecanoyl-phorbol-13-acetate, and mezerein, that are thought to stimulate recombination to determine whether they affect the reversion from Tk- to Tk+. Only mitomycin C increased the number of Tk+ revertants.
Evaluation of the active functional groups and structural rearrangement of parthenolide derivatives on their potential anticancer activity

NASA Astrophysics Data System (ADS)

Srakaew, Veeranuch; Tachaboonyakiat, Wanpen

2017-05-01

Two parthenolide derivatives (PDs) were synthesized by chemical modification of parthenolide with concentrated hydrochloric acid and to evaluate their cytotoxicity to Hep-G2 cells in terms of their active functional groups and polarity. The chemical structures of the PDs were characterized by Fourier transform infrared, nuclear magnetic resonance and high resolution mass spectroscopy. Two PDs (PD1 and PD2) were fractionated by silica gel column chromatography with a Rf of 0.37 and 0.19, respectively, in a 1:1 (v/v) hexane: ethyl acetate mobile phase, indicating that PD1 was less polar than PD2. Compared to the parent parthenolide, both PD1 and PD2 had lost the active carbon-carbon double bond and epoxide functional groups, but retained the active 14-methyl and α-methylene-γ-butyrolactone groups. Although PD1 and PD2 possessed similar functional groups, they differed in their structural arrangement and consequentially their polarity. PD1 and PD2 exhibited an in vitro IC50 against the Hep-G2 cell line of 41.0 and 94.0 μg/ml, respectively, which was weaker than that for parthenolide (<1 μg/ml). Thus, the ranked polarity of PD2 > PD1 > parthenolide was inversely related to their cytotoxicity against the Hep-G2 cell line (parthenolide > PD1 > PD2). The obtained PDs may be potential novel anticancer substances.
Identification of novel drugs to target dormant micrometastases.

PubMed

Hurst, Robert E; Hauser, Paul J; You, Youngjae; Bailey-Downs, Lora C; Bastian, Anja; Matthews, Stephen M; Thorpe, Jessica; Earle, Christine; Bourguignon, Lilly Y W; Ihnat, Michael A

2015-05-14

Cancer-specific survival has changed remarkably little over the past half century, mainly because metastases that are occult at diagnosis and generally resistant to chemotherapy subsequently develop months, years or even decades following definitive therapy. Targeting the dormant micrometastases responsible for these delayed or occult metastases would represent a major new tool in cancer patient management. Our hypothesis is that these metastases develop from micrometastatic cells that are suppressed by normal extracellular matrix (ECM). A new screening method was developed that compared the effect of drugs on the proliferation of cells grown on a normal ECM gel (small intestine submucosa, SISgel) to cells grown on plastic cell culture plates. The desired endpoint was that cells on SISgel were more sensitive than the same cells grown as monolayers. Known cancer chemotherapeutic agents show the opposite pattern. Screening 13,000 compounds identified two leads with low toxicity in mice and EC50 values in the range of 3-30 μM, depending on the cell line, and another two leads that were too toxic to mice to be useful. In a novel flank xenograft method of suppressed/dormant cells co-injected with SISgel into the flank, the lead compounds significantly eliminated the suppressed cells, whereas conventional chemotherapeutics were ineffective. Using a 4T1 triple negative breast cancer model, modified for physiological metastatic progression, as predicted, both lead compounds reduced the number of large micrometastases/macrometastases in the lung. One of the compounds also targeted cancer stem cells (CSC) isolated from the parental line. The CSC also retained their stemness on SISgel. Mechanistic studies showed a mild, late apoptotic response and depending on the compound, a mild arrest either at S or G2/M in the cell cycle. In summary we describe a novel, first in class set of compounds that target micrometastatic cells and prevent their reactivation to form recurrent tumors/macrometastases.

Selecting antagonistic antibodies that control differentiation through inducible expression in embryonic stem cells

PubMed Central

Melidoni, Anna N.; Dyson, Michael R.; Wormald, Sam; McCafferty, John

2013-01-01

Antibodies that modulate receptor function have great untapped potential in the control of stem cell differentiation. In contrast to many natural ligands, antibodies are stable, exquisitely specific, and are unaffected by the regulatory mechanisms that act on natural ligands. Here we describe an innovative system for identifying such antibodies by introducing and expressing antibody gene populations in ES cells. Following induced antibody expression and secretion, changes in differentiation outcomes of individual antibody-expressing ES clones are monitored using lineage-specific gene expression to identify clones that encode and express signal-modifying antibodies. This in-cell expression and reporting system was exemplified by generating blocking antibodies to FGF4 and its receptor FGFR1β, identified through delayed onset of ES cell differentiation. Functionality of the selected antibodies was confirmed by addition of exogenous antibodies to three different ES reporter cell lines, where retained expression of pluripotency markers Oct4, Nanog, and Rex1 was observed. This work demonstrates the potential for discovery and utility of functional antibodies in stem cell differentiation. This work is also unique in constituting an example of ES cells carrying an inducible antibody that causes a functional protein “knock-down” and allows temporal control of stable signaling components at the protein level. PMID:24082130
Infection of Polarized Cultures of Human Intestinal Epithelial Cells with Hepatitis A Virus: Vectorial Release of Progeny Virions through Apical Cellular Membranes

PubMed Central

Blank, Christian A.; Anderson, David A.; Beard, Michael; Lemon, Stanley M.

2000-01-01

Although hepatitis A virus (HAV) is typically transmitted by the fecal-oral route, little is known of its interactions with cells of the gastrointestinal tract. We studied the replication of HAV in polarized cultures of Caco-2 cells, a human cell line which retains many differentiated functions of small intestinal epithelial cells. Virus uptake was 30- to 40-fold more efficient when the inoculum was placed on the apical rather than the basolateral surface of these cells, suggesting a greater abundance of the cellular receptor for HAV on the apical surface. Infection proceeded without cytopathic effect and did not influence transepithelial resistance or the diffusion of inulin across cell monolayers. Nonetheless, there was extensive release of progeny virus, which occurred almost exclusively into apical supernatant fluids (36.4% ± 12.5% of the total virus yield compared with 0.23% ± 0.13% release into basolateral fluids). Brefeldin A caused a profound inhibition of HAV replication, but also selectively reduced apical release of virus. These results indicate that polarized human epithelial cell cultures undergo vectorial infection with HAV and that virus release is largely restricted to the apical membrane. Virus release occurs in the absence of cytopathic effect and may involve cellular vesicular transport mechanisms. PMID:10864660
Model studies of diffusion-controlled (2-hydroxyethyl methacrylate) HEMA hydrogel membranes for controlled release of proteins

NASA Astrophysics Data System (ADS)

Appawu, Jennifer A. M.

This thesis project consisted of three main components that were connected by roots in chemical analysis for studies in tissue engineering. The first part focused on characterizing the structural parameters of synthetic cross-linked poly (2-hydroxyethyl methacrylate) (Poly(HEMA) hydrogel membranes to determine optimal formulations for clinical studies. Poly(HEMA) membranes were loaded with Keratincocyte Growth Factor (KGF) for controlled release studies. Protein loading and release kinetics were determined with fluorescence spectroscopy. The spatial distribution of a protein in the membrane was determined using Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS). The last part of the project focused on determining the biological effects of the polymer membranes in-vitro with a model cell line and a pilot in-vivo animal study. Based on the components completed in this project, five chapters are included in this dissertation document and are summarized below. A new protocol was developed using fluorescence spectroscopy that measured the rate of protein diffusion into cross-linked polymer membranes by measuring the change in the fluorescence intensity of the protein solution. This technique was also able to detect a conformational change that occurs within protein when KGF was imbibed within these cross-linked polymer membranes. ToF-SIMS chemical imaging and 3D depth profiling was used to determine the spatial distribution of KGF protein in frozen-hydrated HEMA hydrogel membranes. The 3D depth profiles showed that the KGF protein was aggregated in bright spots that indicated that KGF was not spatially homogenous on the surface and through the depth profiles. 3D depth profiles of the membranes studied at various times during release studies show that areas with aggregated proteins were retained during release, and at times with maximum release. The interpretation of the bright regions is that the KGf protein interacted with the cross-linked network of the hydrogel membranes, making it not available for release. The in-vitro biological experiments with the HaCaT cell line showed that the HEMA hydrogels were capable of sustaining cell viability, proliferation, and adhesion through cell adhesion and wounding experiments. The pilot in-vivo animal study also revealed that KGF protein had retained its pharmacological activity. The study also showed that the KGF protein enhanced the rate of wound closure.
Upregulated ATM gene expression and activated DNA crosslink-induced damage response checkpoint in Fanconi anemia: implications for carcinogenesis.

PubMed

Yamamoto, Kazuhiko; Nihrane, Abdallah; Aglipay, Jason; Sironi, Juan; Arkin, Steven; Lipton, Jeffrey M; Ouchi, Toru; Liu, Johnson M

2008-01-01

Fanconi anemia (FA) predisposes to hematopoietic failure, birth defects, leukemia, and squamous cell carcinoma of the head and neck (HNSCC) and cervix. The FA/BRCA pathway includes 8 members of a core complex and 5 downstream gene products closely linked with BRCA1 or BRCA2. Precancerous lesions are believed to trigger the DNA damage response (DDR), and we focused on the DDR in FA and its putative role as a checkpoint barrier to cancer. In primary fibroblasts with mutations in the core complex FANCA protein, we discovered that basal expression and phosphorylation of ATM (ataxia telangiectasia mutated) and p53 induced by irradiation (IR) or mitomycin C (MMC) were upregulated. This heightened response appeared to be due to increased basal levels of ATM in cultured FANCA-mutant cells, highlighting the new observation that ATM can be regulated at the transcriptional level in addition to its well-established activation by autophosphorylation. Functional analysis of this response using gamma-H2AX foci as markers of DNA double-stranded breaks (DSBs) demonstrated abnormal persistence of only MMC- and not IR-induced foci. Thus, we describe a processing defect that leads to general DDR upregulation but specific persistence of DNA crosslinker-induced damage response foci. Underscoring the significance of these findings, we found resistance to DNA crosslinker-induced cell cycle arrest and apoptosis in a TP53-mutant, patient-derived HNSCC cell line, whereas a lymphoblastoid cell line derived from this same individual was not mutated at TP53 and retained DNA crosslinker sensitivity. Our results suggest that cancer in FA may arise from selection for cells that escape from a chronically activated DDR checkpoint.
Targeted Disruption of the β2-Microglobulin Gene Minimizes the Immunogenicity of Human Embryonic Stem Cells.

PubMed

Wang, Dachun; Quan, Yuan; Yan, Qing; Morales, John E; Wetsel, Rick A

2015-10-01

Human embryonic stem cells (hESCs) are a promising source of cells for tissue regeneration, yet histoincompatibility remains a major challenge to their clinical application. Because the human leukocyte antigen class I (HLA-I) molecules are the primary mediators of immune rejection, we hypothesized that cells derived from a hESC line lacking HLA-I expression could be transplanted without evoking a robust immune response from allogeneic recipients. In the present study, we used the replacement targeting strategy to delete exons 2 and 3 of β2-microglobulin on both gene alleles in hESCs. Because β2-microglobulin serves as the HLA-I light chain, disruption of the β2-microglobulin gene led to complete HLA-I deficiency on the cell surface of hESCs and their derivatives. Therefore, these cells were resistant to CD8+ T-cell-mediated destruction. Although interferon-γ (IFN-γ) treatment significantly induced β2-microglobulin expression, promoting CD8+ T cell-mediated killing of control hESCs and their derivatives, CD8+ T-cell-mediated cytotoxicity was barely observed with β2-microglobulin-null hESCs and their derivatives treated with IFN-γ. This genetic manipulation to disrupt HLA-I expression did not affect the self-renewal capacity, genomic stability, or pluripotency of hESCs. Despite being relatively sensitive to natural killer (NK) cell-mediated killing due to the lack of HLA-I expression, when transplanted into NK cell-depleted immunocompetent mice, β2-microglobulin-null hESCs developed into tumors resembling those derived from control hESCs in severe combined immunodeficiency mice. These results demonstrate that β2-microglobulin-null hESCs significantly reduce immunogenicity to CD8+ T cells and might provide a renewable source of cells for tissue regeneration without the need for HLA matching in the future. This study reports the generation of a novel β2-microglobulin (B2M)-/- human embryonic stem cell (hESC) line. Differentiated mature cells from this line do not express cell surface human leukocyte antigen molecules even after interferon-γ stimulation and are resistant to alloreactive CD8+ T cells. Moreover, this B2M-/- hESC line contains no off-target integration or cleavage events, is devoid of stable B2M mRNA, exhibits a normal karyotype, and retains its self-renewal capacity, genomic stability, and pluripotency. Although B2M-/- hESC-derived cells are more susceptible to natural killer (NK) cells, murine transplantation studies have indicated that they are, overall, much less immunogenic than normal hESCs. Thus, these data show for the first time that, in vivo, the advantages provided by B2M-/- hESC-derived cells in avoiding CD8+ T-cell killing appear significantly greater than any disadvantage caused by increased susceptibility to NK cells. ©AlphaMed Press.
Targeted Disruption of the β2-Microglobulin Gene Minimizes the Immunogenicity of Human Embryonic Stem Cells

PubMed Central

Quan, Yuan; Yan, Qing; Morales, John E.

2015-01-01

Human embryonic stem cells (hESCs) are a promising source of cells for tissue regeneration, yet histoincompatibility remains a major challenge to their clinical application. Because the human leukocyte antigen class I (HLA-I) molecules are the primary mediators of immune rejection, we hypothesized that cells derived from a hESC line lacking HLA-I expression could be transplanted without evoking a robust immune response from allogeneic recipients. In the present study, we used the replacement targeting strategy to delete exons 2 and 3 of β2-microglobulin on both gene alleles in hESCs. Because β2-microglobulin serves as the HLA-I light chain, disruption of the β2-microglobulin gene led to complete HLA-I deficiency on the cell surface of hESCs and their derivatives. Therefore, these cells were resistant to CD8+ T-cell-mediated destruction. Although interferon-γ (IFN-γ) treatment significantly induced β2-microglobulin expression, promoting CD8+ T cell-mediated killing of control hESCs and their derivatives, CD8+ T-cell-mediated cytotoxicity was barely observed with β2-microglobulin-null hESCs and their derivatives treated with IFN-γ. This genetic manipulation to disrupt HLA-I expression did not affect the self-renewal capacity, genomic stability, or pluripotency of hESCs. Despite being relatively sensitive to natural killer (NK) cell-mediated killing due to the lack of HLA-I expression, when transplanted into NK cell-depleted immunocompetent mice, β2-microglobulin-null hESCs developed into tumors resembling those derived from control hESCs in severe combined immunodeficiency mice. These results demonstrate that β2-microglobulin-null hESCs significantly reduce immunogenicity to CD8+ T cells and might provide a renewable source of cells for tissue regeneration without the need for HLA matching in the future. Significance This study reports the generation of a novel β2-microglobulin (B2M)−/− human embryonic stem cell (hESC) line. Differentiated mature cells from this line do not express cell surface human leukocyte antigen molecules even after interferon-γ stimulation and are resistant to alloreactive CD8+ T cells. Moreover, this B2M−/− hESC line contains no off-target integration or cleavage events, is devoid of stable B2M mRNA, exhibits a normal karyotype, and retains its self-renewal capacity, genomic stability, and pluripotency. Although B2M−/− hESC-derived cells are more susceptible to natural killer (NK) cells, murine transplantation studies have indicated that they are, overall, much less immunogenic than normal hESCs. Thus, these data show for the first time that, in vivo, the advantages provided by B2M−/− hESC-derived cells in avoiding CD8+ T-cell killing appear significantly greater than any disadvantage caused by increased susceptibility to NK cells. PMID:26285657
The long-term label retaining population of the renal papilla arises through divergent regional growth of the kidney.

PubMed

Adams, Derek C; Oxburgh, Leif

2009-09-01

Long-term pulse chase experiments previously identified a sizable population of BrdU-retaining cells within the renal papilla. The origin of these cells has been unclear, and in this work we test the hypothesis that they become quiescent early during the course of kidney development and organ growth. Indeed, we find that BrdU-retaining cells of the papilla can be labeled only by pulsing with BrdU from embryonic (E) day 11.25 to postnatal (P) day 7, the approximate period of kidney development in the mouse. BrdU signal in the cortex and outer medulla is rapidly diluted by cellular proliferation during embryonic development and juvenile growth, whereas cells within the papilla differentiate and exit the cell cycle during organogenesis. Indeed, by E17.5, little or no active proliferation can be seen in the distal papilla, indicating maturation of this structure in a distal-to-proximal manner during organogenesis. We conclude that BrdU-retaining cells of the papilla represent a population of cells that quiesce during embryonic development and localize within a region of the kidney that matures early. We therefore propose that selective papillary retention of BrdU arises through a combination of regionalized slowing of, and exit from, the cell cycle within the papilla during the period of ongoing kidney development, and extensive proliferative growth of the juvenile kidney resulting in dilution of BrdU below the detection level in extra-papillary regions.
Proteomic validation of protease drug targets: pharmacoproteomics of matrix metalloproteinase inhibitor drugs using isotope-coded affinity tag labelling and tandem mass spectrometry.

PubMed

Butler, G S; Overall, C M

2007-01-01

We illustrate the use of quantitative proteomics, namely isotope-coded affinity tag labelling and tandem mass spectrometry, to assess the targets and effects of the blockade of matrix metalloproteinases by an inhibitor drug in a breast cancer cell culture system. Treatment of MT1-MMP-transfected MDA-MB-231 cells with AG3340 (Prinomastat) directly affected the processing a multitude of matrix metalloproteinase substrates, and indirectly altered the expression of an array of other proteins with diverse functions. Therefore, broad spectrum blockade of MMPs has wide-ranging biological consequences. In this human breast cancer cell line, secreted substrates accumulated uncleaved in the conditioned medium and plasma membrane protein substrates were retained on the cell surface, due to reduced processing and shedding of these proteins (cell surface receptors, growth factors and bioactive molecules) to the medium in the presence of the matrix metalloproteinase inhibitor. Hence, proteomic investigation of drug-perturbed cellular proteomes can identify new protease substrates and at the same time provides valuable information for target validation, drug efficacy and potential side effects prior to commitment to clinical trials.
Hyper-reactive cloned mice generated by direct nuclear transfer of antigen-specific CD4+ T cells.

PubMed

Kaminuma, Osamu; Katayama, Kazufumi; Inoue, Kimiko; Saeki, Mayumi; Nishimura, Tomoe; Kitamura, Noriko; Shimo, Yusuke; Tofukuji, Soichi; Ishida, Satoru; Ogonuki, Narumi; Kamimura, Satoshi; Oikawa, Mami; Katoh, Shigeki; Mori, Akio; Shichijo, Michitaka; Hiroi, Takachika; Ogura, Atsuo

2017-06-01

T-cell receptor (TCR)-transgenic mice have been employed for evaluating antigen-response mechanisms, but their non-endogenous TCR might induce immune response differently than the physiologically expressed TCR Nuclear transfer cloning produces animals that retain the donor genotype in all tissues including germline and immune systems. Taking advantage of this feature, we generated cloned mice that carry endogenously rearranged TCR genes from antigen-specific CD4 + T cells. We show that T cells of the cloned mice display distinct developmental pattern and antigen reactivity because of their endogenously pre-rearranged TCRα (rTα) and TCRβ (rTβ) alleles. These alleles were transmitted to the offspring, allowing us to establish a set of mouse lines that show chronic-type allergic phenotypes, that is, bronchial and nasal inflammation, upon local administrations of the corresponding antigens. Intriguingly, the existence of either rTα or rTβ is sufficient to induce in vivo hypersensitivity. These cloned mice expressing intrinsic promoter-regulated antigen-specific TCR are a unique animal model with allergic predisposition for investigating CD4 + T-cell-mediated pathogenesis and cellular commitment in immune diseases. © 2017 The Authors.
Cetuximab-conjugated iron oxide nanoparticles for cancer imaging and therapy

PubMed Central

Tseng, Shih-Heng; Chou, Min-Yuan; Chu, I-Ming

2015-01-01

We have developed a theranostic nanoparticle, ie, cet-PEG-dexSPIONs, by conjugation of the anti-epidermal growth factor receptor (EGFR) monoclonal antibody, cetuximab, to dextran-coated superparamagnetic iron oxide nanoparticles (SPIONs) via periodate oxidation. Approximately 31 antibody molecules were conjugated to each nanoparticle. Cet-PEG-dexSPIONs specifically bind to EGFR-expressing tumor cells and enhance image contrast on magnetic resonance imaging. Cet-PEG-dexSPION-treated A431 cells showed significant inhibition of epidermal growth factor-induced EGFR phosphorylation and enhancement of EGFR internalization and degradation. In addition, a significant increase in apoptosis was detected in EGFR-overexpressing cell lines, A431 and 32D/EGFR, after 24 hours of incubation at 37°C with cet-PEG-dexSPIONs compared with cetuximab alone. The antibody-dependent cell-mediated cytotoxicity of cetuximab was observed in cet-PEG-dexSPIONs. The results demonstrated that cet-PEG-dexSPIONs retained the therapeutic effect of cetuximab in addition to having the ability to target and image EGFR-expressing tumors. Cet-PEG-dexSPIONs represent a promising targeted magnetic probe for early detection and treatment of EGFR-expressing tumor cells. PMID:26056447
Combination of palbociclib and radiotherapy for glioblastoma

PubMed Central

Whittaker, Shane; Madani, Daniel; Joshi, Swapna; Chung, Sylvia A; Johns, Terrance; Day, Bryan; Khasraw, Mustafa; McDonald, Kerrie L

2017-01-01

The cyclin-dependent kinase inhibitor, palbociclib has shown compelling efficacy in breast cancer patients. Several pre-clinical studies of glioblastoma (GBM) have also shown palbociclib to be efficacious. In this study, we investigated palbociclib in combination with radiation therapy (RT) for treating GBM. We tested palbociclib (with and without RT) on four patient-derived cell lines (PDCLs; RB1 retained; CDKN2A loss). We investigated the impact of therapy on the cell cycle and apoptosis using flow cytometry, in vitro. Balb/c nude mice were intracranially injected with the PDCL, GBM-L1 and treated orally with palbociclib (with and without RT). Overall survival was measured. Palbociclib treatment resulted in a significant increase in the percentage of cells in the G1 cell cycle phase. Apoptotic cell death, measured by Annexin V was induced. Palbociclib combined with RT acted synergistically with the significant impediment of colony formation. The oral treatment of mice with palbociclib did not show any significant survival advantage when compared to control mice, however when combined with RT, a survival advantage of 8 days was observed. Our results support the use of palbociclib as an adjuvant treatment to RT and warrant translation to the clinic. PMID:28690875
A Genomewide RNAi Screen for Genes That Affect the Stability, Distribution and Function of P Granules in Caenorhabditis elegans

PubMed Central

Updike, Dustin L.; Strome, Susan

2009-01-01

P granules are non-membrane-bound organelles found in the germ-line cytoplasm throughout Caenorhabditis elegans development. Like their “germ granule” counterparts in other animals, P granules are thought to act as determinants of the identity and special properties of germ cells, properties that include the unique ability to give rise to all tissues of future generations of an organism. Therefore, understanding how P granules work is critical to understanding how cellular immortality and totipotency are retained, gained, and lost. Here we report on a genomewide RNAi screen in C. elegans, which identified 173 genes that affect the stability, localization, and function of P granules. Many of these genes fall into specific classes with shared P-granule phenotypes, allowing us to better understand how cellular processes such as protein degradation, translation, splicing, nuclear transport, and mRNA homeostasis converge on P-granule assembly and function. One of the more striking phenotypes is caused by the depletion of CSR-1, an Argonaute associated with an endogenous siRNA pathway that functions in the germ line. We show that CSR-1 and two other endo-siRNA pathway members, the RNA-dependent RNA polymerase EGO-1 and the helicase DRH-3, act to antagonize RNA and P-granule accumulation in the germ line. Our findings strengthen the emerging view that germ granules are involved in numerous aspects of RNA metabolism, including an endo-siRNA pathway in germ cells. PMID:19805813
Deletion of the Vaccinia Virus I2 Protein Interrupts Virion Morphogenesis, Leading to Retention of the Scaffold Protein and Mislocalization of Membrane-Associated Entry Proteins.

PubMed

Hyun, Seong-In; Weisberg, Andrea; Moss, Bernard

2017-08-01

The I2L open reading frame of vaccinia virus (VACV) encodes a conserved 72-amino-acid protein with a putative C-terminal transmembrane domain. Previous studies with a tetracycline-inducible mutant demonstrated that I2-deficient virions are defective in cell entry. The purpose of the present study was to determine the step of replication or entry that is affected by loss of the I2 protein. Fluorescence microscopy experiments showed that I2 colocalized with a major membrane protein of immature and mature virions. We generated a cell line that constitutively expressed I2 and allowed construction of the VACV I2L deletion mutant vΔI2. As anticipated, vΔI2 was unable to replicate in cells that did not express I2. Unexpectedly, morphogenesis was interrupted at a stage after immature virion formation, resulting in the accumulation of dense spherical particles instead of brick-shaped mature virions with well-defined core structures. The abnormal particles retained the D13 scaffold protein of immature virions, were severely deficient in the transmembrane proteins that comprise the entry fusion complex (EFC), and had increased amounts of unprocessed membrane and core proteins. Total lysates of cells infected with vΔI2 also had diminished EFC proteins due to instability attributed to their hydrophobicity and failure to be inserted into viral membranes. A similar instability of EFC proteins had previously been found with unrelated mutants blocked earlier in morphogenesis that also accumulated viral membranes retaining the D13 scaffold. We concluded that I2 is required for virion morphogenesis, release of the D13 scaffold, and the association of EFC proteins with viral membranes. IMPORTANCE Poxviruses comprise a large family that infect vertebrates and invertebrates, cause disease in both in humans and in wild and domesticated animals, and are being engineered as vectors for vaccines and cancer therapy. In addition, investigations of poxviruses have provided insights into many aspects of cell biology. The I2 protein is conserved in all poxviruses that infect vertebrates, suggesting an important role. The present study revealed that this protein is essential for vaccinia virus morphogenesis and that its absence results in an accumulation of deformed virus particles retaining the scaffold protein and deficient in surface proteins needed for cell entry. Copyright © 2017 American Society for Microbiology.
Use of yeast spores for microencapsulation of enzymes.

PubMed

Shi, Libing; Li, Zijie; Tachikawa, Hiroyuki; Gao, Xiao-Dong; Nakanishi, Hideki

2014-08-01

Here, we report a novel method to produce microencapsulated enzymes using Saccharomyces cerevisiae spores. In sporulating cells, soluble secreted proteins are transported to the spore wall. Previous work has shown that the spore wall is capable of retaining soluble proteins because its outer layers work as a diffusion barrier. Accordingly, a red fluorescent protein (RFP) fusion of the α-galactosidase, Mel1, expressed in spores was observed in the spore wall even after spores were subjected to a high-salt wash in the presence of detergent. In vegetative cells, however, the cell wall cannot retain the RFP fusion. Although the spore wall prevents diffusion of proteins, it is likely that smaller molecules, such as sugars, pass through it. In fact, spores can contain much higher α-galactosidase activity to digest melibiose than vegetative cells. When present in the spore wall, the enzyme acquires resistance to environmental stresses including enzymatic digestion and high temperatures. The outer layers of the spore wall are required to retain enzymes but also decrease accessibility of the substrates. However, mutants with mild spore wall defects can retain and stabilize the enzyme while still permitting access to the substrate. In addition to Mel1, we also show that spores can retain the invertase. Interestingly the encapsulated invertase has significantly lower activity toward raffinose than toward sucrose.This suggests that substrate selectivity could be altered by the encapsulation.
PROTEIN KINASE C δ IS A THERAPEUTIC TARGET IN MALIGNANT MELANOMA WITH NRAS MUTATION

PubMed Central

Takashima, Asami; English, Brandon; Chen, Zhihong; Cao, Juxiang; Cui, Rutao; Williams, Robert M.; Faller, Douglas V.

2014-01-01

NRAS is the second most frequently mutated gene in melanoma. Previous reports have demonstrated the sensitivity of cancer cell lines carrying KRAS mutations to apoptosis initiated by inhibition of protein kinase C delta (PKCδ). Here, we report that PKCδ inhibition is cytotoxic in melanomas with primary NRAS mutations. Novel small-molecule inhibitors of PKCδ were designed as chimeric hybrids of two naturally-occurring PKCδ inhibitors, staurosporine and rottlerin. The specific hypothesis interrogated and validated is that combining two domains of two naturally-occurring PKCδ inhibitors into a chimeric or hybrid structure retains biochemical and biological activity, and improves PKCδ isozyme selectivity. We have devised a potentially general synthetic protocol to make these chimeric species using Molander trifluorborate coupling chemistry. Inhibition of PKCδ, by siRNA or small molecule inhibitors, suppressed the growth of multiple melanoma cell lines carrying NRAS mutations, mediated via caspase-dependent apoptosis. Following PKCδ inhibition, the stress-responsive JNK pathway was activated, leading to the activation of H2AX. Consistent with recent reports on the apoptotic role of phospho-H2AX, knockdown of H2AX prior to PKCδ inhibition mitigated the induction of caspase-dependent apoptosis. Furthermore, PKCδ inhibition effectively induced cytotoxicity in BRAF-mutant melanoma cell lines that had evolved resistance to a BRAF inhibitor, suggesting the potential clinical application of targeting PKCδ in patients who have relapsed following treatment with BRAF inhibitors. Taken together, the present work demonstrates that inhibition of PKCδ by novel small molecule inhibitors causes caspase-dependent apoptosis mediated via the JNK-H2AX pathway in melanomas with NRAS mutations or BRAF inhibitor-resistance. PMID:24506253
Uptake and subcellular distribution of [3H]arachidonic acid in murine fibrosarcoma cells measured by electron microscope autoradiography

PubMed Central

1985-01-01

We have used quantitative electron microscope autoradiography to study uptake and distribution of arachidonate in HSDM1C1 murine fibrosarcoma cells and in EPU-1B, a mutant HSDM1C1 line defective in high affinity arachidonate uptake. Cells were labeled with [3H]arachidonate for 15 min, 40 min, 2 h, or 24 h. Label was found almost exclusively in cellular phospholipids; 92-96% of incorporated radioactivity was retained in cells during fixation and tissue processing. All incorporated radioactivity was found to be associated with cellular membranes. Endoplasmic reticulum (ER) contained the bulk of [3H]arachidonate at all time points in both cell types, while mitochondria, which contain a large portion of cellular membrane, were labeled slowly and to substantially lower specific activity. Plasma membrane (PM) also labeled slowly, achieving a specific activity only one-sixth that of ER at 15 min in HSDM1C1 cells (6% of total label) and one-third of ER in EPU-1B (10% of total label). Nuclear membrane (NM) exhibited the highest specific activity of labeling at 15 min in HSDM1C1 cells (twice that of ER) but was not preferentially labeled in the mutant. Over 24 h, PM label intensity increased to that of ER in both cell lines. However, NM activity diminished in HSDM1C1 cells by 24 h to a small fraction of that in ER. In response to agonists, HSDM1C1 cells release labeled arachidonate for eicosanoid synthesis most readily when they have been labeled for short times. Our results therefore suggest that NM and ER, sites of cyclooxygenase in murine fibroblasts, are probably sources for release of [3H]arachidonate, whereas PM and mitochondria are unlikely to be major sources of eicosanoid precursors. PMID:3926781
Hypothalamic neurogenesis persists in the aging brain and is controlled by energy-sensing IGF-I pathway.

PubMed

Chaker, Zayna; George, Caroline; Petrovska, Marija; Caron, Jean-Baptiste; Lacube, Philippe; Caillé, Isabelle; Holzenberger, Martin

2016-05-01

Hypothalamic tanycytes are specialized glial cells lining the third ventricle. They are recently identified as adult stem and/or progenitor cells, able to self-renew and give rise to new neurons postnatally. However, the long-term neurogenic potential of tanycytes and the pathways regulating lifelong cell replacement in the adult hypothalamus are largely unexplored. Using inducible nestin-CreER(T2) for conditional mutagenesis, we performed lineage tracing of adult hypothalamic stem and/or progenitor cells (HySC) and demonstrated that new neurons continue to be born throughout adult life. This neurogenesis was targeted to numerous hypothalamic nuclei and produced different types of neurons in the dorsal periventricular regions. Some adult-born neurons integrated the median eminence and arcuate nucleus during aging and produced growth hormone releasing hormone. We showed that adult hypothalamic neurogenesis was tightly controlled by insulin-like growth factors (IGF). Knockout of IGF-1 receptor from hypothalamic stem and/or progenitor cells increased neuronal production and enhanced α-tanycyte self-renewal, preserving this stem cell-like population from age-related attrition. Our data indicate that adult hypothalamus retains the capacity of cell renewal, and thus, a substantial degree of structural plasticity throughout lifespan. Copyright © 2016 Elsevier Inc. All rights reserved.
Detection of BrdU-label Retaining Cells in the Lacrimal Gland: Implications for Tissue Repair

PubMed Central

You, Samantha; Tariq, Ayesha; Kublin, Claire L.; Zoukhri, Driss

2011-01-01

The purpose of the present study was to determine if the lacrimal gland contains 5-bromo-2’-deoxyuridine (BrdU)-label retaining cells and if they are involved in tissue repair. Animals were pulsed daily with BrdU injections for 7 consecutive days. After a chase period of 2, 4, or 12 weeks, the animals were sacrificed and the lacrimal glands were removed and processed for BrdU immunostaining. In another series of experiments, the lacrimal glands of 12-week chased animals were either left untreated or were injected with interleukin 1 (IL-1) to induce injury. Two and half day post-injection, the lacrimal glands were removed and processed for BrdU immunostaining. After 2 and 4 week of chase period, a substantial number of lacrimal gland cells were BrdU+ (11.98 ± 1.84 and 7.95 ± 1.83 BrdU+ cells/mm2, respectively). After 12 weeks of chase, there was a 97% decline in the number of BrdU+ cells (0.38 ± 0.06 BrdU+ cells/mm2), suggesting that these BrdU-label retaining cells may represent slow-cycling adult stem/progenitor cells. In support of this hypothesis, the number of BrdU labeled cells increased over 7-fold during repair of the lacrimal gland (control: 0.41 ± 0.09 BrdU+ cells/mm2, injured: 2.91 ± 0.62 BrdU+ cells/mm2). Furthermore, during repair, among BrdU+ cells 58.2 ± 3.6 % were acinar cells, 26.4 ± 4.1% were myoepithelial cells, 0.4 ± 0.4% were ductal cells, and 15.0 ± 3.0% were stromal cells. We conclude that the murine lacrimal gland contains BrdU-label retaining cells that are mobilized following injury to generate acinar, myoepithelial and ductal cells. PMID:22101331
Selective Inhibition of Tumor Growth by Clonal NK Cells Expressing an ErbB2/HER2-Specific Chimeric Antigen Receptor

PubMed Central

Schönfeld, Kurt; Sahm, Christiane; Zhang, Congcong; Naundorf, Sonja; Brendel, Christian; Odendahl, Marcus; Nowakowska, Paulina; Bönig, Halvard; Köhl, Ulrike; Kloess, Stephan; Köhler, Sylvia; Holtgreve-Grez, Heidi; Jauch, Anna; Schmidt, Manfred; Schubert, Ralf; Kühlcke, Klaus; Seifried, Erhard; Klingemann, Hans G; Rieger, Michael A; Tonn, Torsten; Grez, Manuel; Wels, Winfried S

2015-01-01

Natural killer (NK) cells are an important effector cell type for adoptive cancer immunotherapy. Similar to T cells, NK cells can be modified to express chimeric antigen receptors (CARs) to enhance antitumor activity, but experience with CAR-engineered NK cells and their clinical development is still limited. Here, we redirected continuously expanding and clinically usable established human NK-92 cells to the tumor-associated ErbB2 (HER2) antigen. Following GMP-compliant procedures, we generated a stable clonal cell line expressing a humanized CAR based on ErbB2-specific antibody FRP5 harboring CD28 and CD3ζ signaling domains (CAR 5.28.z). These NK-92/5.28.z cells efficiently lysed ErbB2-expressing tumor cells in vitro and exhibited serial target cell killing. Specific recognition of tumor cells and antitumor activity were retained in vivo, resulting in selective enrichment of NK-92/5.28.z cells in orthotopic breast carcinoma xenografts, and reduction of pulmonary metastasis in a renal cell carcinoma model, respectively. γ-irradiation as a potential safety measure for clinical application prevented NK cell replication, while antitumor activity was preserved. Our data demonstrate that it is feasible to engineer CAR-expressing NK cells as a clonal, molecularly and functionally well-defined and continuously expandable cell therapeutic agent, and suggest NK-92/5.28.z cells as a promising candidate for use in adoptive cancer immunotherapy. PMID:25373520
Characterization of a family of structurally related glycoproteins expressing beta 1-6-branched asparagine-linked oligosaccharides in human colon carcinoma cells.

PubMed

Laferté, S; Loh, L C

1992-04-01

Previous studies have established that metastatic tumour cells express high levels of beta 1-6-branched Asn-linked oligosaccharides which can be detected with the lectin leucoagglutinin (L-PHA) [Dennis, Laferté, Waghorne, Breitman & Kerbel (1987) Science 236, 582-585]. In order to identify L-PHA-binding glycoproteins which may play a role specifically in colon cancer, we have prepared monoclonal antibodies (MAbs) to the moderately well-differentiated human colon carcinoma cell line HT29. In this paper we present the initial characterization of a family of structurally related L-PHA-binding glycoproteins detected by MAb 1H9 which are differentially expressed and processed by HT29 cells and by two other human colon carcinoma cell lines, SW480 and SW620. In contrast to HT29, the SW480 and SW620 cell lines were established from a poorly differentiated grade III/IV primary tumour and one of its lymph node metastases respectively. MAb 1H9 detects in HT29 cells a conformational determinant present on three L-PHA-binding glycoproteins of 100, 70 and 25kDa, as well as a 74 kDa glycoprotein with high-mannose-type Asn-linked oligosaccharides. Pulse-chase experiments and peptide mapping analyses revealed that the 74 kDa and 100 kDa species are related by carbohydrate processing and are probably derived from a common 76 kDa precursor. On the other hand, the 70 kDa glycoprotein is synthesized from an endoglycosidase H-sensitive precursor of 56 kDa which is structurally related to, but distinct from, the aforementioned 76 kDa precursor. In addition, the 100 kDa species is secreted into the culture medium, whereas the 70 kDa glycoprotein is retained intracellularly. SW480 and SW620 cells showed qualitative and quantitative differences from HT29 cells, including increased secretion of a smaller L-PHA-binding glycoprotein of 92 kDa into the culture medium, as well as apparent differences in glycosylation of the intracellular 66 kDa glycoprotein. These results suggested that the expression, glycosylation and subcellular localization of this family of L-PHA-binding glycoproteins may correlate with the differentiation status of colon cancer cells and/or reflect biochemical changes. characteristic of more progressive metastatic tumours.

Working towards recalcitrance mechanisms: increased xylan and homogalacturonan production by overexpression of GAlactUronosylTransferase12 (GAUT12) causes increased recalcitrance and decreased growth in Populus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Biswal, Ajaya K.; Atmodjo, Melani A.; Pattathil, Sivakumar

The development of fast-growing hardwood trees as a source of lignocellulosic biomass for biofuel and biomaterial production requires a thorough understanding of the plant cell wall structure and function that underlie the inherent recalcitrance properties of woody biomass. Downregulation of GAUT12.1 in Populus deltoides was recently reported to result in improved biomass saccharification, plant growth, and biomass yield. To further understand GAUT12.1 function in biomass recalcitrance and plant growth, here we report the effects of P. trichocarpa GAUT12.1 overexpression in P. deltoides. Increasing GAUT12.1 transcript expression by 7-49% in P. deltoides PtGAUT12.1-overexpression (OE) lines resulted in a nearly complete oppositemore » biomass saccharification and plant growth phenotype to that observed previously in PdGAUT12.1-knockdown (KD) lines. This also included significantly reduced glucose, xylose, and total sugar release (12-13%), plant height (6-54%), stem diameter (8-40%), and overall total aerial biomass yield (48-61%) in 3-month-old, greenhouse-grown PtGAUT12.1-OE lines compared to controls. Total lignin content was unaffected by the gene overexpression. Importantly, selected PtGAUT12.1-OE lines retained the recalcitrance and growth phenotypes upon growth for 9 months in the greenhouse and 2.8 years in the field. PtGAUT12.1-OE plants had significantly smaller leaves with lower relative water content, and significantly reduced stem wood xylem cell numbers and size. At the cell wall level, xylose and galacturonic acid contents increased markedly in total cell walls as well as in soluble and insoluble cell wall extracts, consistent with increased amounts of xylan and homogalacturonan in the PtGAUT12.1-OE lines. This led to increased cell wall recalcitrance, as manifested by the 9-15% reduced amounts of recovered extractable wall materials and 8-15% greater amounts of final insoluble pellet in the PtGAUT12.1-OE lines compared to controls. The combined phenotype and chemotype data from P. deltoides PtGAUT12.1-OE and PdGAUT12.1-KD transgenics clearly establish GAUT12.1 as a recalcitrance- and growth-associated gene in poplar. Overall, the data support the hypothesis that GAUT12.1 synthesizes either an HG-containing primer for xylan synthesis or an HG glycan required for proper xylan deposition, anchoring, and/or architecture in the wall, and the possibility of HG and xylan glycans being connected to each other by a base-sensitive covalent linkage.« less
Working towards recalcitrance mechanisms: increased xylan and homogalacturonan production by overexpression of GAlactUronosylTransferase12 (GAUT12) causes increased recalcitrance and decreased growth in Populus

DOE PAGES

Biswal, Ajaya K.; Atmodjo, Melani A.; Pattathil, Sivakumar; ...

2018-01-17

The development of fast-growing hardwood trees as a source of lignocellulosic biomass for biofuel and biomaterial production requires a thorough understanding of the plant cell wall structure and function that underlie the inherent recalcitrance properties of woody biomass. Downregulation of GAUT12.1 in Populus deltoides was recently reported to result in improved biomass saccharification, plant growth, and biomass yield. To further understand GAUT12.1 function in biomass recalcitrance and plant growth, here we report the effects of P. trichocarpa GAUT12.1 overexpression in P. deltoides. Increasing GAUT12.1 transcript expression by 7-49% in P. deltoides PtGAUT12.1-overexpression (OE) lines resulted in a nearly complete oppositemore » biomass saccharification and plant growth phenotype to that observed previously in PdGAUT12.1-knockdown (KD) lines. This also included significantly reduced glucose, xylose, and total sugar release (12-13%), plant height (6-54%), stem diameter (8-40%), and overall total aerial biomass yield (48-61%) in 3-month-old, greenhouse-grown PtGAUT12.1-OE lines compared to controls. Total lignin content was unaffected by the gene overexpression. Importantly, selected PtGAUT12.1-OE lines retained the recalcitrance and growth phenotypes upon growth for 9 months in the greenhouse and 2.8 years in the field. PtGAUT12.1-OE plants had significantly smaller leaves with lower relative water content, and significantly reduced stem wood xylem cell numbers and size. At the cell wall level, xylose and galacturonic acid contents increased markedly in total cell walls as well as in soluble and insoluble cell wall extracts, consistent with increased amounts of xylan and homogalacturonan in the PtGAUT12.1-OE lines. This led to increased cell wall recalcitrance, as manifested by the 9-15% reduced amounts of recovered extractable wall materials and 8-15% greater amounts of final insoluble pellet in the PtGAUT12.1-OE lines compared to controls. The combined phenotype and chemotype data from P. deltoides PtGAUT12.1-OE and PdGAUT12.1-KD transgenics clearly establish GAUT12.1 as a recalcitrance- and growth-associated gene in poplar. Overall, the data support the hypothesis that GAUT12.1 synthesizes either an HG-containing primer for xylan synthesis or an HG glycan required for proper xylan deposition, anchoring, and/or architecture in the wall, and the possibility of HG and xylan glycans being connected to each other by a base-sensitive covalent linkage.« less
Glycosylphosphatidylinositol Anchor Modification Machinery Deficiency Is Responsible for the Formation of Pro-Prion Protein (PrP) in BxPC-3 Protein and Increases Cancer Cell Motility*

PubMed Central

Yang, Liheng; Gao, Zhenxing; Hu, Lipeng; Wu, Guiru; Yang, Xiaowen; Zhang, Lihua; Zhu, Ying; Wong, Boon-Seng; Xin, Wei; Sy, Man-Sun; Li, Chaoyang

2016-01-01

The normal cellular prion protein (PrP) is a glycosylphosphatidylinositol (GPI)-anchored cell surface glycoprotein. However, in pancreatic ductal adenocarcinoma cell lines, such as BxPC-3, PrP exists as a pro-PrP retaining its glycosylphosphatidylinositol (GPI) peptide signaling sequence. Here, we report the identification of another pancreatic ductal adenocarcinoma cell line, AsPC-1, which expresses a mature GPI-anchored PrP. Comparison of the 24 genes involved in the GPI anchor modification pathway between AsPC-1 and BxPC-3 revealed 15 of the 24 genes, including PGAP1 and PIG-F, were down-regulated in the latter cells. We also identified six missense mutations in DPM2, PIG-C, PIG-N, and PIG-P alongside eight silent mutations. When BxPC-3 cells were fused with Chinese hamster ovary (CHO) cells, which lack endogenous PrP, pro-PrP was successfully converted into mature GPI-anchored PrP. Expression of the individual gene, such as PGAP1, PIG-F, or PIG-C, into BxPC-3 cells does not result in phosphoinositide-specific phospholipase C sensitivity of PrP. However, when PIG-F but not PIG-P is expressed in PGAP1-expressing BxPC-3 cells, PrP on the surface of the cells becomes phosphoinositide-specific phospholipase C-sensitive. Thus, low expression of PIG-F and PGAP1 is the major factor contributing to the accumulation of pro-PrP. More importantly, BxPC-3 cells expressing GPI-anchored PrP migrate much slower than BxPC-3 cells bearing pro-PrP. In addition, GPI-anchored PrP-bearing AsPC-1 cells also migrate slower than pro-PrP bearing BxPC-3 cells, although both cells express filamin A. “Knocking out” PRNP in BxPC-3 cell drastically reduces its migration. Collectively, these results show that multiple gene irregularity in BxPC-3 cells is responsible for the formation of pro-PrP, and binding of pro-PrP to filamin A contributes to enhanced tumor cell motility. PMID:26683373
Aflatoxin B1-induced DNA adduct formation and p53 mutations in CYP450-expressing human liver cell lines.

PubMed

Macé, K; Aguilar, F; Wang, J S; Vautravers, P; Gómez-Lechón, M; Gonzalez, F J; Groopman, J; Harris, C C; Pfeifer, A M

1997-07-01

Epidemiological evidence has been supporting a relationship between dietary aflatoxin B1 (AFB1) exposure, development of human primary hepatocellular carcinoma (HCC) and mutations in the p53 tumor suppressor gene. However, the correlation between the observed p53 mutations, the AFB1 DNA adducts and their activation pathways has not been elucidated. Development of relevant cellular in vitro models, taking into account species and tissue specificity, could significantly contribute to the knowledge of cytotoxicity and genotoxicity mechanisms of chemical procarcinogens, such as AFB1, in humans. For this purpose a non-tumorigenic SV40-immortalized human liver epithelial cell line (THLE cells) which retained most of the phase II enzymes, but had markedly reduced phase I activities was used for stable expression of the human CYP1A2, CYP2A6, CYP2B6 and CYP3A4 cDNA. The four genetically engineered cell lines (T5-1A2, T5-2A6, T5-2B6 and T5-3A4) produced high levels of the specific CYP450 proteins and showed comparable or higher catalytic activities related to the CYP450 expression when compared to human hepatocytes. The T5-1A2, T5-2A6, T5-2B6 and T5-3A4 cell lines exhibited a very high sensitivity to the cytotoxic effects of AFB1 and were approximately 125-, 2-, 2- and 15-fold, respectively, more sensitive than the control T5-neo cells, transfected with an expressing vector which does not contain CYP450 cDNA. In the CYP450-expressing cells, nanomolar doses of AFB1-induced DNA adduct formation including AFB1-N7-guanine, -pyrimidyl and -diol adducts. In addition, the T5-1A2 cells showed AFM1-DNA adducts. At similar levels of total DNA adducts, both the T5-1A2 and T5-3A4 cells showed, at codon 249 of the p53 gene, AGG to AGT transversions at a relative frequency of 15x10(-6). In contrast, only the T5-3A4 cells showed CCC to ACC transversion at codon 250 at a high frequency, whereas the second most frequent mutations found in the T5-1A2 cells were C to T transitions at the first and second position of the codon 250. No significant AFB1-induced p53 mutations could be detected in the T5-2A6 cells. Therefore, the differential expression of specific CYP450 genes in human hepatocytes can modulate the cytotoxicity, DNA adduct levels and frequency of p53 mutations produced by AFB1.
Formation of multimeric antibodies for self-delivery of active monomers.

PubMed

Dekel, Yaron; Machluf, Yossy; Gefen, Tal; Eidelshtein, Gennady; Kotlyar, Alexander; Bram, Yaron; Shahar, Ehud; Reslane, Farah; Aizenshtein, Elina; Pitcovski, Jacob

2017-11-01

Proteins and peptides have been used as drugs for almost a century. Technological advances in the past 30 years have enabled the production of pure, stable proteins in vast amounts. In contrast, administration of proteins based on their native active conformation (and thus necessitating the use of subcutaneous injections) has remained solely unchanged. The therapeutic anti-HER2 humanized monoclonal immunoglobulin (IgG) Trastuzumab (Herceptin) is a first line of the treatment for breast cancer. Chicken IgY is a commercially important polyclonal antibody (Ab). These Abs were examined for their ability to self-assemble and form ordered aggregates, by several biophysical methods. Atomic force microscopy analyses revealed the formation of multimeric nanostructures. The biological activity of multimeric IgG or IgY particles was retained and restored, in a dilution/time-dependent manner. IgG activity was confirmed by a binding assay using HER2 + human breast cancer cell line, SKBR3, while IgY activity was confirmed by ELISA assay using the VP2 antigen. Competition assay with native Herceptin antibodies demonstrated that the binding availability of the multimer formulation remained unaffected. Under long incubation periods, IgG multimers retained five times more activity than native IgG. In conclusion, the multimeric antibody formulations can serve as a storage depositories and sustained-release particles. These two important characteristics make this formulation promising for future novel administration protocols and altogether bring to light a different conceptual approach for the future use of therapeutic proteins as self-delivery entities rather than conjugated/encapsulated to other bio-compounds.
A conserved WW domain-like motif regulates invariant chain-dependent cell-surface transport of the NKG2D ligand ULBP2.

PubMed

Uhlenbrock, Franziska; van Andel, Esther; Andresen, Lars; Skov, Søren

2015-08-01

Malignant cells expressing NKG2D ligands on their cell surface can be directly sensed and killed by NKG2D-bearing lymphocytes. To ensure this immune recognition, accumulating evidence suggests that NKG2D ligands are trafficed via alternative pathways to the cell surface. We have previously shown that the NKG2D ligand ULBP2 traffics over an invariant chain (Ii)-dependent pathway to the cell surface. This study set out to elucidate how Ii regulates ULBP2 cell-surface transport: We discovered conserved tryptophan (Trp) residues in the primary protein sequence of ULBP1-6 but not in the related MICA/B. Substitution of Trp to alanine resulted in cell-surface inhibition of ULBP2 in different cancer cell lines. Moreover, the mutated ULBP2 constructs were retained and not degraded inside the cell, indicating a crucial role of this conserved Trp-motif in trafficking. Finally, overexpression of Ii increased surface expression of wt ULBP2 while Trp-mutants could not be expressed, proposing that this Trp-motif is required for an Ii-dependent cell-surface transport of ULBP2. Aberrant soluble ULBP2 is immunosuppressive. Thus, targeting a distinct protein module on the ULBP2 sequence could counteract this abnormal expression of ULBP2. Copyright © 2015 Elsevier Ltd. All rights reserved.
A novel method to study contact inhibition of locomotion using micropatterned substrates

PubMed Central

Scarpa, Elena; Roycroft, Alice; Theveneau, Eric; Terriac, Emmanuel; Piel, Matthieu; Mayor, Roberto

2013-01-01

Summary The concept of contact inhibition of locomotion (CIL) describes the ability of a cell to change the direction of its movement after contact with another cell. It has been shown to be responsible for physiological and developmental processes such as wound healing, macrophage dispersion and neural crest cell migration; whereas its loss facilitates cancer cell invasion and metastatic dissemination. Different assays have been developed to analyze CIL in tissue culture models. However, these methods have several caveats. Collisions happen at low frequency between freely migrating cells and the orientation of the cells at the time of contact is not predictable. Moreover, the computational analysis required by these assays is often complicated and it retains a certain degree of discretion. Here, we show that confinement of neural crest cell migration on a single dimension by using a micropatterned substrate allows standardized and predictable cell–cell collision. CIL can thus easily be quantified by direct measurement of simple cellular parameters such as the distance between nuclei after collision. We tested some of the signaling pathways previously identified as involved in CIL, such as small GTPases and non-canonical Wnt signaling, using this new method for CIL analysis. The restricted directionality of migration of cells in lines is a powerful strategy to obtain higher predictability and higher efficiency of the CIL response upon cell–cell collisions. PMID:24143276
Mitochondrial control of cell death induced by hyperosmotic stress.

PubMed

Criollo, Alfredo; Galluzzi, Lorenzo; Maiuri, M Chiara; Tasdemir, Ezgi; Lavandero, Sergio; Kroemer, Guido

2007-01-01

HeLa and HCT116 cells respond differentially to sorbitol, an osmolyte able to induce hypertonic stress. In these models, sorbitol promoted the phenotypic manifestations of early apoptosis followed by complete loss of viability in a time-, dose-, and cell type-specific fashion, by eliciting distinct yet partially overlapping molecular pathways. In HCT116 but not in HeLa cells, sorbitol caused the mitochondrial release of the caspase-independent death effector AIF, whereas in both cell lines cytochrome c was retained in mitochondria. Despite cytochrome c retention, HeLa cells exhibited the progressive activation of caspase-3, presumably due to the prior activation of caspase-8. Accordingly, caspase inhibition prevented sorbitol-induced killing in HeLa, but only partially in HCT116 cells. Both the knock-out of Bax in HCT116 cells and the knock-down of Bax in A549 cells by RNA interference reduced the AIF release and/or the mitochondrial alterations. While the knock-down of Bcl-2/Bcl-X(L) sensitized to sorbitol-induced killing, overexpression of a Bcl-2 variant that specifically localizes to mitochondria (but not of the wild-type nor of a endoplasmic reticulum-targeted form) strongly inhibited sorbitol effects. Thus, hyperosmotic stress kills cells by triggering different molecular pathways, which converge at mitochondria where pro- and anti-apoptotic members of the Bcl-2 family exert their control.
Characterization of porcine partially reprogrammed iPSCs from adipose-derived stem cells.

PubMed

Wei, Chao; Li, Xia; Zhang, Pengfei; Zhang, Yu; Liu, Tong; Jiang, Shaoshuai; Han, Fei; Zhang, Yunhai

2015-05-01

Partially reprogrammed induced pluripotent stem cells (PiPSCs) have great potential for investigating reprogramming mechanisms and represent an alternative potential material for making genetically modified animals and regenerative medicine. To date, PiPSCs have scarcely been reported in detail when compared with mice and humans. In this study, we obtained PiPSCs from porcine adipose-derived stem cells (pADSCs) by ectopic expression of human transcription factors (OCT4, SOX2, c-MYC, and KLF4) in feeder-free condition. The morphology and proliferation activity of porcine PiPSCs (pPiPSCs) were similar to those of porcine fully reprogrammed iPSCs (pFiPSCs); furthermore, pPiPSCs expressed higher levels of the typical surface molecules (CD29) found in pADSCs. However, pPiPSCs were negative for key proteins (NANOG) connected with stemness and possessed lower differentiation ability in vivo and in vitro. When differentiation-inhibiting factors were withdrawn, pPiPSCs-derived cells (pPiPSC-DCs) showed similar features to pADSCs in many aspects, including proliferation, differentiation, and immunosuppression. When both types of cells were used to produce cloned embryos, we found that the blastocyst formation rate of 19DC (one of the pPiPSC-DC cell lines)-derived cloned embryos was obviously higher than that of others. The total cell number of 19DC-derived blastocysts was significantly higher than the 30DC (one pFiPSC-DC cell line)-derived blastocysts. In all, through limited differentiation ability, the proliferation activity of pPiPSCs is similar to that of pFiPSCs, and pPiPSCs can retain several of the features of pADSCs, which are beneficial to cell therapy. Furthermore, the differentiation of pPiPSCs is more favorable for producing high-quality reconstructed embryos. © 2015 Society for Reproduction and Fertility.
Discoidin domain receptor 2 (DDR2) regulates proliferation of endochondral cells in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kawai, Ikuma; Hisaki, Tomoka; Sugiura, Koji

2012-10-26

Highlights: Black-Right-Pointing-Pointer Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase. Black-Right-Pointing-Pointer DDR2 regulates cell proliferation, cell adhesion, migration, and extracellular matrix remodeling. Black-Right-Pointing-Pointer We produced in vitro and in vivo model to better understand the role of DDR2. Black-Right-Pointing-Pointer DDR2 might play an inhibitory role in the proliferation of chondrocyte. -- Abstract: Discoidin domain receptor 2 (DDR2) is a receptor tyrosine kinase that is activated by fibrillar collagens. DDR2 regulates cell proliferation, cell adhesion, migration, and extracellular matrix remodeling. The decrement of endogenous DDR2 represses osteoblastic marker gene expression and osteogenic differentiation in murine preosteoblastic cells, but themore » functions of DDR2 in chondrogenic cellular proliferation remain unclear. To better understand the role of DDR2 signaling in cellular proliferation in endochondral ossification, we inhibited Ddr2 expression via the inhibitory effect of miRNA on Ddr2 mRNA (miDdr2) and analyzed the cellular proliferation and differentiation in the prechondrocyte ATDC5 cell lines. To investigate DDR2's molecular role in endochondral cellular proliferation in vivo, we also produced transgenic mice in which the expression of truncated, kinase dead (KD) DDR2 protein is induced, and evaluated the DDR2 function in cellular proliferation in chondrocytes. Although the miDdr2-transfected ATDC5 cell lines retained normal differentiation ability, DDR2 reduction finally promoted cellular proliferation in proportion to the decreasing ratio of Ddr2 expression, and it also promoted earlier differentiation to cartilage cells by insulin induction. The layer of hypertrophic chondrocytes in KD Ddr2 transgenic mice was not significantly thicker than that of normal littermates, but the layer of proliferative chondrocytes in KD-Ddr2 transgenic mice was significantly thicker than that of normal littermates. Taken together, our data demonstrated that DDR2 might play a local and essential role in the proliferation of chondrocytes.« less
Colony Organization in the Green Alga Botryococcus braunii (Race B) Is Specified by a Complex Extracellular Matrix

PubMed Central

Weiss, Taylor L.; Roth, Robyn; Goodson, Carrie; Vitha, Stanislav; Black, Ian; Azadi, Parastoo; Rusch, Jannette; Holzenburg, Andreas

2012-01-01

Botryococcus braunii is a colonial green alga whose cells associate via a complex extracellular matrix (ECM) and produce prodigious amounts of liquid hydrocarbons that can be readily converted into conventional combustion engine fuels. We used quick-freeze deep-etch electron microscopy and biochemical/histochemical analysis to elucidate many new features of B. braunii cell/colony organization and composition. Intracellular lipid bodies associate with the chloroplast and endoplasmic reticulum (ER) but show no evidence of being secreted. The ER displays striking fenestrations and forms a continuous subcortical system in direct contact with the cell membrane. The ECM has three distinct components. (i) Each cell is surrounded by a fibrous β-1, 4- and/or β-1, 3-glucan-containing cell wall. (ii) The intracolonial ECM space is filled with a cross-linked hydrocarbon network permeated with liquid hydrocarbons. (iii) Colonies are enclosed in a retaining wall festooned with a fibrillar sheath dominated by arabinose-galactose polysaccharides, which sequesters ECM liquid hydrocarbons. Each cell apex associates with the retaining wall and contributes to its synthesis. Retaining-wall domains also form “drapes” between cells, with some folding in on themselves and penetrating the hydrocarbon interior of a mother colony, partitioning it into daughter colonies. We propose that retaining-wall components are synthesized in the apical Golgi apparatus, delivered to apical ER fenestrations, and assembled on the surfaces of apical cell walls, where a proteinaceous granular layer apparently participates in fibril morphogenesis. We further propose that hydrocarbons are produced by the nonapical ER, directly delivered to the contiguous cell membrane, and pass across the nonapical cell wall into the hydrocarbon-based ECM. PMID:22941913
Colony organization in the green alga Botryococcus braunii is specified by a complex extracellular matrix

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weiss, Taylor L.; Roth, Robyn; Goodson, Carrie

Botryococcus braunii is a colonial green alga whose cells associate via a complex extracellular matrix (ECM) and produce prodigious amounts of liquid hydrocarbons that can be readily converted into conventional combustion engine fuels. We used quickfreeze deep-etch electron microscopy and biochemical/histochemical analysis to elucidate many new features of B. braunii cell/colony organization and composition. Intracellular lipid bodies associate with the chloroplast and endoplasmic reticulum (ER) but show no evidence of being secreted. The ER displays striking fenestrations and forms a continuous subcortical system in direct contact with the cell membrane. The ECM has three distinct components. (i) Each cell ismore » surrounded by a fibrous β-1, 4- and/or β-1, 3-glucan-containing cell wall. (ii) The intracolonial ECM space is filled with a cross-linked hydrocarbon network permeated with liquid hydrocarbons. (iii) Colonies are enclosed in a retaining wall festooned with a fibrillar sheath dominated by arabinose-galactose polysaccharides, which sequesters ECM liquid hydrocarbons. Each cell apex associates with the retaining wall and contributes to its synthesis. Retaining-wall domains also form "drapes" between cells, with some folding in on themselves and penetrating the hydrocarbon interior of a mother colony, partitioning it into daughter colonies. In addition, we propose that retaining-wall components are synthesized in the apical Golgi apparatus, delivered to apical ER fenestrations, and assembled on the surfaces of apical cell walls, where a proteinaceous granular layer apparently participates in fibril morphogenesis. We further propose that hydrocarbons are produced by the nonapical ER, directly delivered to the contiguous cell membrane, and pass across the nonapical cell wall into the hydrocarbon-based ECM.« less
Colony organization in the green alga Botryococcus braunii is specified by a complex extracellular matrix

DOE PAGES

Weiss, Taylor L.; Roth, Robyn; Goodson, Carrie; ...

2012-08-31

Botryococcus braunii is a colonial green alga whose cells associate via a complex extracellular matrix (ECM) and produce prodigious amounts of liquid hydrocarbons that can be readily converted into conventional combustion engine fuels. We used quickfreeze deep-etch electron microscopy and biochemical/histochemical analysis to elucidate many new features of B. braunii cell/colony organization and composition. Intracellular lipid bodies associate with the chloroplast and endoplasmic reticulum (ER) but show no evidence of being secreted. The ER displays striking fenestrations and forms a continuous subcortical system in direct contact with the cell membrane. The ECM has three distinct components. (i) Each cell ismore » surrounded by a fibrous β-1, 4- and/or β-1, 3-glucan-containing cell wall. (ii) The intracolonial ECM space is filled with a cross-linked hydrocarbon network permeated with liquid hydrocarbons. (iii) Colonies are enclosed in a retaining wall festooned with a fibrillar sheath dominated by arabinose-galactose polysaccharides, which sequesters ECM liquid hydrocarbons. Each cell apex associates with the retaining wall and contributes to its synthesis. Retaining-wall domains also form "drapes" between cells, with some folding in on themselves and penetrating the hydrocarbon interior of a mother colony, partitioning it into daughter colonies. In addition, we propose that retaining-wall components are synthesized in the apical Golgi apparatus, delivered to apical ER fenestrations, and assembled on the surfaces of apical cell walls, where a proteinaceous granular layer apparently participates in fibril morphogenesis. We further propose that hydrocarbons are produced by the nonapical ER, directly delivered to the contiguous cell membrane, and pass across the nonapical cell wall into the hydrocarbon-based ECM.« less
Decellularized scaffold of cryopreserved rat kidney retains its recellularization potential.

PubMed

Chani, Baldeep; Puri, Veena; Sobti, Ranbir C; Jha, Vivekanand; Puri, Sanjeev

2017-01-01

The multi-cellular nature of renal tissue makes it the most challenging organ for regeneration. Therefore, till date whole organ transplantations remain the definitive treatment for the end stage renal disease (ESRD). The shortage of available organs for the transplantation has, thus, remained a major concern as well as an unsolved problem. In this regard generation of whole organ scaffold through decellularization followed by regeneration of the whole organ by recellularization is being viewed as a potential alternative for generating functional tissues. Despite its growing interest, the optimal processing to achieve functional organ still remains unsolved. The biggest challenge remains is the time line for obtaining kidney. Keeping these facts in mind, we have assessed the effects of cryostorage (3 months) on renal tissue architecture and its potential for decellularization and recellularization in comparison to the freshly isolated kidneys. The light microscopy exploiting different microscopic stains as well as immuno-histochemistry and Scanning electron microscopy (SEM) demonstrated that ECM framework is well retained following kidney cryopreservation. The strength of these structures was reinforced by calculating mechanical stress which confirmed the similarity between the freshly isolated and cryopreserved tissue. The recellularization of these bio-scaffolds, with mesenchymal stem cells quickly repopulated the decellularized structures irrespective of the kidneys status, i.e. freshly isolated or the cryopreserved. The growth pattern employing mesenchymal stem cells demonstrated their equivalent recellularization potential. Based on these observations, it may be concluded that cryopreserved kidneys can be exploited as scaffolds for future development of functional organ.
21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.

Code of Federal Regulations, 2013 CFR

2013-04-01

... forceps cover, biopsy tray without biopsy instruments, line clamp, nonpowered rectal probe, nonelectrical..., gastro-urology probe and director, nonself-retaining retractor, laparotomy rings, nonelectrical snare...
21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.

Code of Federal Regulations, 2012 CFR

2012-04-01

... forceps cover, biopsy tray without biopsy instruments, line clamp, nonpowered rectal probe, nonelectrical..., gastro-urology probe and director, nonself-retaining retractor, laparotomy rings, nonelectrical snare...
21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.

Code of Federal Regulations, 2014 CFR

2014-04-01

... forceps cover, biopsy tray without biopsy instruments, line clamp, nonpowered rectal probe, nonelectrical..., gastro-urology probe and director, nonself-retaining retractor, laparotomy rings, nonelectrical snare...
21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.

Code of Federal Regulations, 2010 CFR

2010-04-01

... forceps cover, biopsy tray without biopsy instruments, line clamp, nonpowered rectal probe, nonelectrical..., gastro-urology probe and director, nonself-retaining retractor, laparotomy rings, nonelectrical snare...
21 CFR 876.4730 - Manual gastroenterology-urology surgical instrument and accessories.

Code of Federal Regulations, 2011 CFR

2011-04-01

... forceps cover, biopsy tray without biopsy instruments, line clamp, nonpowered rectal probe, nonelectrical..., gastro-urology probe and director, nonself-retaining retractor, laparotomy rings, nonelectrical snare...
Drug transporter expression profiling in a three-dimensional kidney proximal tubule in vitro nephrotoxicity model.

PubMed

Diekjürgen, Dorina; Grainger, David W

2018-05-09

Given currently poor toxicity translational predictions for drug candidates, improved mechanistic understanding underlying nephrotoxicity and drug renal clearance is needed to improve drug development and safety screening. Therefore, better relevant and well-characterized in vitro screening models are required to reliably predict human nephrotoxicity. Because kidney proximal tubules are central to active drug uptake and secretion processes and therefore to nephrotoxicity, this study acquired regio-specific expression data from recently reported primary proximal tubule three-dimensional (3D) hyaluronic acid gel culture and non-gel embedded cultured murine proximal tubule suspensions used in nephrotoxicity assays. Quantitative assessment of the mRNA expression of 21 known kidney tubule markers and important proximal tubule transporters with known roles in drug transport was obtained. Asserting superior gene expression levels over current commonly used two-dimensional (2D) kidney cell culture lines was the study objective. Hence, we compare previously published gel-based 3D proximal tubule fragment culture and their non-gel suspensions for up to 1 week. We demonstrate that 3D tubule culture exhibits superior gene expression levels and profiles compared to published commonly used 2D kidney cell lines (Caki-1 and HK-2) in plastic plate monocultures. Additionally, nearly all tested genes retain mRNA expression after 7 days in both proximal tubule cultures, a limitation of 2D cell culture lines. Importantly, gel presence is shown not to interfere with the gene expression assay. Western blots confirm protein expression of OAT1 and 3 and OCT2. Functional transport assays confirm their respective transporter functions in vitro. Overall, results validate retention of essential toxicity-relevant transporters in this published 3D proximal tubule model over conventional 2D kidney cell cultures, producing opportunities for more reliable, sensitive, and comprehensive drug toxicity studies relevant to drug development and nephrotoxicity goals.

Hypervariable Domain of Nonstructural Protein nsP3 of Venezuelan Equine Encephalitis Virus Determines Cell-Specific Mode of Virus Replication

PubMed Central

Foy, Niall J.; Akhrymuk, Maryna; Shustov, Alexander V.; Frolova, Elena I.

2013-01-01

Venezuelan equine encephalitis virus (VEEV) is one of the most pathogenic members of the Alphavirus genus in the Togaviridae family. This genus is divided into the Old World and New World alphaviruses, which demonstrate profound differences in pathogenesis, replication, and virus-host interactions. VEEV is a representative member of the New World alphaviruses. The biology of this virus is still insufficiently understood, particularly the function of its nonstructural proteins in RNA replication and modification of the intracellular environment. One of these nonstructural proteins, nsP3, contains a hypervariable domain (HVD), which demonstrates very low overall similarity between different alphaviruses, suggesting the possibility of its function in virus adaptation to different hosts and vectors. The results of our study demonstrate the following. (i) Phosphorylation of the VEEV nsP3-specific HVD does not play a critical role in virus replication in cells of vertebrate origin but is important for virus replication in mosquito cells. (ii) The VEEV HVD is not required for viral RNA replication in the highly permissive BHK-21 cell line. In fact, it can be either completely deleted or replaced by a heterologous protein sequence. These variants require only one or two additional adaptive mutations in nsP3 and/or nsP2 proteins to achieve an efficiently replicating phenotype. (iii) However, the carboxy-terminal repeat in the VEEV HVD is indispensable for VEEV replication in the cell lines other than BHK-21 and plays a critical role in formation of VEEV-specific cytoplasmic protein complexes. Natural VEEV variants retain at least one of the repeated elements in their nsP3 HVDs. PMID:23637407
Combined introduction of Bmi-1 and hTERT immortalizes human adipose tissue-derived stromal cells with low risk of transformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tatrai, Peter, E-mail: peter.tatrai@biomembrane.hu; Department of Biochemistry and Molecular Biology, Medical and Health Science Center, University of Debrecen, Egyetem ter 1, H-4032 Debrecen; Szepesi, Aron, E-mail: aron.szepesi@biomembrane.hu

2012-05-25

Highlights: Black-Right-Pointing-Pointer We immortalized human adipose stromal cells (ASCs) with hTERT, Bmi-1, and SV40T. Black-Right-Pointing-Pointer hTERT-only ASCs are prone to transformation, while Bmi-only ASCs become senescent. Black-Right-Pointing-Pointer SV40T introduced along with hTERT abrogates proliferation control and multipotency. Black-Right-Pointing-Pointer hTERT combined with Bmi-1 yields stable phenotype up to 140 population doublings. -- Abstract: Adipose tissue-derived stromal cells (ASCs) are increasingly being studied for their usefulness in regenerative medicine. However, limited life span and donor-dependent variation of primary cells such as ASCs present major hurdles to controlled and reproducible experiments. We therefore aimed to establish immortalized ASC cell lines that provide steadymore » supply of homogeneous cells for in vitro work while retain essential features of primary cells. To this end, combinations of human telomerase reverse transcriptase (hTERT), murine Bmi-1, and SV40 large T antigen (SV40T) were introduced by lentiviral transduction into ASCs. The resulting cell lines ASC{sup hTERT}, ASC{sup Bmi-1}, ASC{sup Bmi-1+hTERT} and ASC{sup SV40T+hTERT} were tested for transgene expression, telomerase activity, surface immunomarkers, proliferation, osteogenic and adipogenic differentiation, karyotype, tumorigenicity, and cellular senescence. All cell lines have maintained expression of characteristic surface immunomarkers, and none was tumorigenic. However, ASC{sup Bmi-1} had limited replicative potential, while the rapidly proliferating ASC{sup SV40T+hTERT} acquired chromosomal aberrations, departed from MSC phenotype, and lost differentiation capacity. ASC{sup hTERT} and ASC{sup hTERT+Bmi-1}, on the other hand, preserved all essential MSC features and did not senesce after 100 population doublings. Notably, a subpopulation of ASC{sup hTERT} also acquired aberrant karyotype and showed signs of transformation after long-term culture. In conclusion, hTERT alone was sufficient to extend the life span of human ASC, but ASC{sup hTERT} are prone to transformation during extensive subculturing. The combination of Bmi-1 and hTERT successfully immortalized human ASCs without significantly perturbing their phenotype or biological behavior.« less
New insights into the antioxidant activity and cytotoxicity of arzanol and effect of methylation on its biological properties.

PubMed

Rosa, Antonella; Atzeri, Angela; Nieddu, Mariella; Appendino, Giovanni

2017-06-01

The heterodimeric phloroglucinyl pyrone arzanol (Arz) has raised considerable interest because of its antiviral, anti-inflammatory, and antioxidant activity. We have investigated the effect of methylation of the pyrone moiety on the antioxidant activity and cytotoxicity of Arz. This manoeuvre, that left the polyphenolic moiety unscathed, was nevertheless detrimental for antioxidant activity in both the cholesterol thermal degradation- and the Cu 2+ -induced liposome oxidation assays, providing evidence of structure-activity relationships that go beyond the preservation of the polyphenolic pharmacophore. The antioxidant activity of Arz was retained also in the Fe-NTA model of in vivo oxidative stress, with protective effect on the oxidative degradation of plasmatic lipids, unsaturated fatty acids and cholesterol. Both Arz and methylarzanol (Me-Arz) were devoid of toxic effect on colonic differentiated Caco-2 cells up to 100μM, but significantly reduced cancer Caco-2 cell viability at lower dosages. Arz could also selectively reduce viability of other cancer cell lines, [murine melanoma cells (B16F10 cells), human cervical carcinoma cells (HeLa cells)], suggesting that it can act as a selective modulator of cell processes typical of cancer cells. Taken together, our results qualify Arz as a lead structure for further in vivo investigation of its pharmacological potential. Copyright © 2017 Elsevier B.V. All rights reserved.
From the cradle to the grave: activities of GATA-3 throughout T cell development and differentiation

PubMed Central

Hosoya, Tomonori; Maillard, Ivan; Engel, James Douglas

2010-01-01

Summary GATA family transcription factors play multiple vital roles in hematopoiesis in many cell lineages, and in particular, T cells require GATA-3 for execution of several developmental steps. Transcriptional activation of the Gata3 gene is observed throughout T-cell development and differentiation in stage-specific fashion. GATA-3 has been described as a master regulator of T-helper 2 (Th2) cell differentiation in mature CD4+ T cells. During T-cell development in the thymus, its roles in the CD4 vs. CD8 lineage choice and at the β-selection checkpoint are the best characterized. In contrast, its importance prior to β-selection has been obscured both by the developmental heterogeneity of double negative (DN) 1 thymocytes and the paucity of early T-lineage progenitors (ETPs), a subpopulation of DN1 cells that contains the most immature thymic progenitors that retain potent T-lineage developmental potential. By examining multiple lines of in vivo evidence procured through the analysis of Gata3 mutant mice, we have recently demonstrated that GATA-3 is additionally required at the earliest stage of thymopoiesis for the development of the ETP population. Here, we review the characterized functions of GATA-3 at each stage of T-cell development and discuss hypothetical molecular pathways that mediate these functions. PMID:20969588
A high throughput respirometric assay for mitochondrial biogenesis and toxicity

PubMed Central

Beeson, Craig C.; Beeson, Gyda C.; Schnellmann, Rick G.

2010-01-01

Mitochondria are a common target of toxicity for drugs and other chemicals, and results in decreased aerobic metabolism and cell death. In contrast, mitochondrial biogenesis restores cell vitality and there is a need for new agents to induce biogenesis. Current cell-based models of mitochondrial biogenesis or toxicity are inadequate because cultured cell lines are highly glycolytic with minimal aerobic metabolism and altered mitochondrial physiology. In addition, there are no high-throughput, real-time assays that assess mitochondrial function. We adapted primary cultures of renal proximal tubular cells (RPTC) that exhibit in vivo levels of aerobic metabolism, are not glycolytic, and retain higher levels of differentiated functions and used the Seahorse Biosciences analyzer to measure mitochondrial function in real time in multi-well plates. Using uncoupled respiration as a marker of electron transport chain (ETC) integrity, the nephrotoxicants cisplatin, HgCl2 and gentamicin exhibited mitochondrial toxicity prior to decreases in basal respiration and cell death. Conversely, using FCCP-uncoupled respiration as a marker of maximal ETC activity, 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI), SRT1720, resveratrol, daidzein, and metformin produced mitochondrial biogenesis in RPTC. The merger of the RPTC model and multi-well respirometry results in a single high throughput assay to measure mitochondrial biogenesis and toxicity, and nephrotoxic potential. PMID:20465991
The Epstein-Barr virus Bcl-2 homolog, BHRF1, blocks apoptosis by binding to a limited amount of Bim.

PubMed

Desbien, Anthony L; Kappler, John W; Marrack, Philippa

2009-04-07

Current knowledge suggests that the balance between life and death within a cell can be controlled by the stable engagement of Bcl-2-related proapoptotic proteins such as Bak, Bax, and Bim by survival proteins such as Bcl-2. BHRF1 is a prosurvival molecule from Epstein-Barr virus that has a high degree of homology to Bcl-2. To understand how BHRF1 blocks apoptosis, BHRF1 and mutants of BHRF1 were expressed in primary cells and an IL-2-dependent T cell line. BHRF1 bound the Executioner Bak and, when cells were cultured without cytokines, BHRF1 associated with Bim. A point mutation that lost the ability to bind Bak retained its ability to bind Bim and to protect cells. This result demonstrated that it was the capacity of BHRF1 to bind Bim, not Bak, that provided protection. Interestingly, the amount of Bim bound by BHRF1 was minimal when compared with the amount of Bim induced by apoptosis. Thus, BHRF1 does not act by simply absorbing the excess Bim produced while cells prepare for death. Rather, BHRF1 may act either by binding preferentially the most lethal form of Bim or by acting catalytically on Bim to block apoptosis.
Rab1a regulates sorting of early endocytic vesicles

PubMed Central

Mukhopadhyay, Aparna; Quiroz, Jose A.

2014-01-01

We previously reported that Rab1a is associated with asialoorosomucoid (ASOR)-containing early endocytic vesicles, where it is required for their microtubule-based motility. In Rab1a knockdown (KD) cell lines, ASOR failed to segregate from its receptor and, consequently, did not reach lysosomes for degradation, indicating a defect in early endosome sorting. Although Rab1 is required for Golgi/endoplasmic reticulum trafficking, this process was unaffected, likely due to retained expression of Rab1b in these cells. The present study shows that Rab1a has a more general role in endocytic vesicle processing that extends to EGF and transferrin (Tfn) trafficking. Compared with results in control Huh7 cells, EGF accumulated in aggregates within Rab1a KD cells, failing to reach lysosomal compartments. Tfn, a prototypical example of recycling cargo, accumulated in a Rab11-mediated slow-recycling compartment in Rab1a KD cells, in contrast to control cells, which sort Tfn into a fast-recycling Rab4 compartment. These data indicate that Rab1a is an important regulator of early endosome sorting for multiple cargo species. The effectors and accessory proteins recruited by Rab1a to early endocytic vesicles include the minus-end-directed kinesin motor KifC1, while others remain to be discovered. PMID:24407591
Survival of Legionella pneumophila in the cold-water ciliate Tetrahymena vorax

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith-Somerville, H.E.; Huryn, V.B.; Walker, C.

1991-09-01

The processing of phagosomes containing Legionella pneumophila and Escerichia coli were compared in Tetrahymena vorax, a hymenostome ciliated protozoan that prefers lower temperatures. L. pneumophila did not multiply in the ciliate when incubated at 20 to 22C, but vacuoles containing L. pneumophila were retained in the cells for a substantially longer time than vacuoles with E. coli. Electron micrographs showed no evidence of degradation of L. pneumophila cells through 12 h, while E. coli cells in the process of being digested were observed in vacuoles 75 min after the addition of the bacterium T. vorax ingested L. pneumophila normally, butmore » by 10 to 15 min, the vacuolar membrane appeared denser than that surrounding nascent or newly formed phagosomes. In older vacuoles, electron-dense particles lined portions of the membrane. Acidification of the phagosomes indicated by the accumulation of neutral red was similar in T. vorax containing L. pneumophila or E. coli. This ciliate could provide a model for the analysis of virulence-associated intracellular events independent of the replication of L. pneumophila.« less
Efficient killing of CD22{sup +} tumor cells by a humanized diabody-RNase fusion protein

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krauss, Juergen; Arndt, Michaela A.E.; Vu, Bang K.

2005-06-03

We report on the generation of a dimeric immunoenzyme capable of simultaneously delivering two ribonuclease (RNase) effector domains on one molecule to CD22{sup +} tumor cells. As targeting moiety a diabody derived from the previously humanized scFv SGIII with grafted specificity of the murine anti-CD22 mAb RFB4 was constructed. Further engineering the interface of this construct (V{sub L}36{sub Leu{yields}}{sub Tyr}) resulted in a highly robust bivalent molecule that retained the same high affinity as the murine mAb RFB4 (K{sub D} 0.2 nM). A dimeric immunoenzyme comprising this diabody and Rana pipiens liver ribonuclease I (rapLRI) was generated, expressed as solublemore » protein in bacteria, and purified to homogeneity. The dimeric fusion protein killed several CD22{sup +} tumor cell lines with high efficacy (IC{sub 50} = 3-20 nM) and exhibited 9- to 48-fold stronger cytotoxicity than a monovalent rapLRI-scFv counterpart. Our results demonstrate that engineering of dimeric antibody-ribonuclease fusion proteins can markedly enhance their biological efficacy.« less
Homologous recombination between overlapping thymidine kinase gene fragments stably inserted into a mouse cell genome.

PubMed Central

Lin, F L; Sternberg, N

1984-01-01

We have constructed a substrate to study homologous recombination between adjacent segments of chromosomal DNA. This substrate, designated lambda tk2 , consists of one completely defective and one partially defective herpes simplex virus thymidine kinase (tk) gene cloned in bacteriophage lambda DNA. The two genes have homologous 984-base-pair sequences and are separated by 3 kilobases of largely vector DNA. When lambda tk2 DNA was transferred into mouse LMtk- cells by the calcium phosphate method, rare TK+ transformants were obtained that contained many (greater than 40) copies of the unrecombined DNA. Tk- revertants, which had lost most of the copies of unrecombined DNA, were isolated from these TK+-transformed lines. Two of these Tk- lines were further studied by analysis of their reversion back to the Tk+ phenotype. They generated ca. 200 Tk+ revertants per 10(8) cells after growth in nonselecting medium for 5 days. All of these Tk+ revertants have an intact tk gene reconstructed by homologous recombination; they also retain various amounts of unrecombined lambda tk2 DNA. Southern blot analysis suggested that at least some of the recombination events involve unequal sister chromatid exchanges. We also tested three agents, mitomycin C, 12-O-tetradecanoyl-phorbol-13-acetate, and mezerein, that are thought to stimulate recombination to determine whether they affect the reversion from Tk- to Tk+. Only mitomycin C increased the number of Tk+ revertants. Images PMID:6328272
BAX protein expression and clinical outcome in epithelial ovarian cancer.

PubMed

Tai, Y T; Lee, S; Niloff, E; Weisman, C; Strobel, T; Cannistra, S A

1998-08-01

Expression of the pro-apoptotic protein BAX sensitizes ovarian cancer cell lines to paclitaxel in vitro by enhancing the pathway of programmed cell death. The present study was performed to determine the relationship between BAX expression and clinical outcome in 45 patients with newly diagnosed ovarian cancer. BAX protein expression was analyzed by immunohistochemistry, and its relationship with clinical outcome was determined. Assessment of BAX mRNA transcript levels and mutational analysis of the BAX coding region were also performed. BAX protein was expressed at high levels (defined as > or = 50% of tumor cells positive) in tumor tissue from 60% of newly diagnosed patients. All patients whose tumors expressed high levels of BAX achieved a complete response (CR) to first-line chemotherapy that contained paclitaxel plus a platinum analogue, compared with 57% of patients in the low-BAX group (P = .036). After a median follow-up of 1.9 years, the median disease-free survival (DFS) of patients in the high-BAX group has not been reached, compared with a median DFS of 1.1 years for low-BAX expressors (P = .0061). BAX retained independent prognostic significance in multivariate analysis when corrected for stage and histology. BAX mRNA transcripts were easily detected in samples with low BAX protein expression, and no BAX mutations were identified. The correlation between high BAX levels and improved clinical outcome suggests that an intact apoptotic pathway is an important determinant of chemoresponsiveness in ovarian cancer patients who receive paclitaxel.
Manifold seal for fuel cell stack assembly

DOEpatents

Schmitten, Phillip F.; Wright, Maynard K.

1989-01-01

An assembly for sealing a manifold to a stack of fuel cells includes a first resilient member for providing a first sealing barrier between the manifold and the stack. A second resilient member provides a second sealing barrier between the manifold and the stack. The first and second resilient members are retained in such a manner as to define an area therebetween adapted for retaining a sealing composition.
CRISPR/Cas9-mediated reversibly immortalized mouse bone marrow stromal stem cells (BMSCs) retain multipotent features of mesenchymal stem cells (MSCs).

PubMed

Hu, Xue; Li, Li; Yu, Xinyi; Zhang, Ruyi; Yan, Shujuan; Zeng, Zongyue; Shu, Yi; Zhao, Chen; Wu, Xingye; Lei, Jiayan; Li, Yasha; Zhang, Wenwen; Yang, Chao; Wu, Ke; Wu, Ying; An, Liping; Huang, Shifeng; Ji, Xiaojuan; Gong, Cheng; Yuan, Chengfu; Zhang, Linghuan; Liu, Wei; Huang, Bo; Feng, Yixiao; Zhang, Bo; Haydon, Rex C; Luu, Hue H; Reid, Russell R; Lee, Michael J; Wolf, Jennifer Moriatis; Yu, Zebo; He, Tong-Chuan

2017-12-19

Mesenchymal stem cells (MSCs) are multipotent non-hematopoietic progenitor cells that can undergo self-renewal and differentiate into multi-lineages. Bone marrow stromal stem cells (BMSCs) represent one of the most commonly-used MSCs. In order to overcome the technical challenge of maintaining primary BMSCs in long-term culture, here we seek to establish reversibly immortalized mouse BMSCs (imBMSCs). By exploiting CRISPR/Cas9-based homology-directed-repair (HDR) mechanism, we target SV40T to mouse Rosa26 locus and efficiently immortalize mouse BMSCs (i.e., imBMSCs). We also immortalize BMSCs with retroviral vector SSR #41 and establish imBMSC41 as a control line. Both imBMSCs and imBMSC41 exhibit long-term proliferative capability although imBMSC41 cells have a higher proliferation rate. SV40T mRNA expression is 130% higher in imBMSC41 than that in imBMSCs. However, FLP expression leads to 86% reduction of SV40T expression in imBMSCs, compared with 63% in imBMSC41 cells. Quantitative genomic PCR analysis indicates that the average copy number of SV40T and hygromycin is 1.05 for imBMSCs and 2.07 for imBMSC41, respectively. Moreover, FLP expression removes 92% of SV40T in imBMSCs at the genome DNA level, compared with 58% of that in imBMSC41 cells, indicating CRISPR/Cas9 HDR-mediated immortalization of BMSCs can be more effectively reversed than that of retrovirus-mediated random integrations. Nonetheless, both imBMSCs and imBMSC41 lines express MSC markers and are highly responsive to BMP9-induced osteogenic, chondrogenic and adipogenic differentiation in vitro and in vivo . Thus, the engineered imBMSCs can be used as a promising alternative source of primary MSCs for basic and translational research in the fields of MSC biology and regenerative medicine.
CRISPR/Cas9-mediated reversibly immortalized mouse bone marrow stromal stem cells (BMSCs) retain multipotent features of mesenchymal stem cells (MSCs)

PubMed Central

Hu, Xue; Li, Li; Yu, Xinyi; Zhang, Ruyi; Yan, Shujuan; Zeng, Zongyue; Shu, Yi; Zhao, Chen; Wu, Xingye; Lei, Jiayan; Li, Yasha; Zhang, Wenwen; Yang, Chao; Wu, Ke; Wu, Ying; An, Liping; Huang, Shifeng; Ji, Xiaojuan; Gong, Cheng; Yuan, Chengfu; Zhang, Linghuan; Liu, Wei; Huang, Bo; Feng, Yixiao; Zhang, Bo; Haydon, Rex C.; Luu, Hue H.; Reid, Russell R.; Lee, Michael J.; Wolf, Jennifer Moriatis; Yu, Zebo; He, Tong-Chuan

2017-01-01

Mesenchymal stem cells (MSCs) are multipotent non-hematopoietic progenitor cells that can undergo self-renewal and differentiate into multi-lineages. Bone marrow stromal stem cells (BMSCs) represent one of the most commonly-used MSCs. In order to overcome the technical challenge of maintaining primary BMSCs in long-term culture, here we seek to establish reversibly immortalized mouse BMSCs (imBMSCs). By exploiting CRISPR/Cas9-based homology-directed-repair (HDR) mechanism, we target SV40T to mouse Rosa26 locus and efficiently immortalize mouse BMSCs (i.e., imBMSCs). We also immortalize BMSCs with retroviral vector SSR #41 and establish imBMSC41 as a control line. Both imBMSCs and imBMSC41 exhibit long-term proliferative capability although imBMSC41 cells have a higher proliferation rate. SV40T mRNA expression is 130% higher in imBMSC41 than that in imBMSCs. However, FLP expression leads to 86% reduction of SV40T expression in imBMSCs, compared with 63% in imBMSC41 cells. Quantitative genomic PCR analysis indicates that the average copy number of SV40T and hygromycin is 1.05 for imBMSCs and 2.07 for imBMSC41, respectively. Moreover, FLP expression removes 92% of SV40T in imBMSCs at the genome DNA level, compared with 58% of that in imBMSC41 cells, indicating CRISPR/Cas9 HDR-mediated immortalization of BMSCs can be more effectively reversed than that of retrovirus-mediated random integrations. Nonetheless, both imBMSCs and imBMSC41 lines express MSC markers and are highly responsive to BMP9-induced osteogenic, chondrogenic and adipogenic differentiation in vitro and in vivo. Thus, the engineered imBMSCs can be used as a promising alternative source of primary MSCs for basic and translational research in the fields of MSC biology and regenerative medicine. PMID:29340096
Deletion of SLC19A2, the high affinity thiamine transporter, causes selective inner hair cell loss and an auditory neuropathy phenotype.

PubMed

Liberman, M C; Tartaglini, E; Fleming, J C; Neufeld, E J

2006-09-01

Mutations in the gene coding for the high-affinity thiamine transporter Slc19a2 underlie the clinical syndrome known as thiamine-responsive megaloblastic anemia (TRMA) characterized by anemia, diabetes, and sensorineural hearing loss. To create a mouse model of this disease, a mutant line was created with targeted disruption of the gene. Cochlear function is normal in these mutants when maintained on a high-thiamine diet. When challenged with a low-thiamine diet, Slc19a2-null mice showed 40-60 dB threshold elevations by auditory brainstem response (ABR), but only 10-20 dB elevation by otoacoustic emission (OAE) measures. Wild-type mice retain normal hearing on either diet. Cochlear histological analysis showed a pattern uncommon for sensorineural hearing loss: selective loss of inner hair cells after 1-2 weeks on low thiamine and significantly greater inner than outer hair cell loss after longer low-thiamine challenges. Such a pattern is consistent with the observed discrepancy between ABR and OAE threshold shifts. The possible role of thiamine transport in other reported cases of selective inner hair cell loss is considered.
Mitochondrial functions of RECQL4 are required for the prevention of aerobic glycolysis-dependent cell invasion.

PubMed

Kumari, Jyoti; Hussain, Mansoor; De, Siddharth; Chandra, Suruchika; Modi, Priyanka; Tikoo, Shweta; Singh, Archana; Sagar, Chandrasekhar; Sepuri, Naresh Babu V; Sengupta, Sagar

2016-04-01

Germline mutations in RECQL4 helicase are associated with Rothmund-Thomson syndrome, which is characterized by a predisposition to cancer. RECQL4 localizes to the mitochondria, where it acts as an accessory factor during mitochondrial DNA replication. To understand the specific mitochondrial functions of RECQL4, we created isogenic cell lines, in which the mitochondrial localization of the helicase was either retained or abolished. The mitochondrial integrity was affected due to the absence of RECQL4 in mitochondria, leading to a decrease in F1F0-ATP synthase activity. In cells where RECQL4 does not localize to mitochondria, the membrane potential was decreased, whereas ROS levels increased due to the presence of high levels of catalytically inactive SOD2. Inactive SOD2 accumulated owing to diminished SIRT3 activity. Lack of the mitochondrial functions of RECQL4 led to aerobic glycolysis that, in turn, led to an increased invasive capability within these cells. Together, this study demonstrates for the first time that, owing to its mitochondrial functions, the accessory mitochondrial replication helicase RECQL4 prevents the invasive step in the neoplastic transformation process. © 2016. Published by The Company of Biologists Ltd.
DR-nm23 gene expression in neuroblastoma cells: relationship to integrin expression, adhesion characteristics, and differentiation.

PubMed

Amendola, R; Martinez, R; Negroni, A; Venturelli, D; Tanno, B; Calabretta, B; Raschellà, G

1997-09-03

Neuroblastoma, a childhood tumor originating from cells of the embryonic neural crest, retains the ability to differentiate, yielding cells with epithelial-Schwann-like, neuronal, or melanocytic characteristics. Since nm23 gene family members have been proposed to play a role in cellular differentiation, as well as in metastasis suppression, we investigated whether and how DR-nm23, a recently identified third member of the human nm23 gene family, might be involved in neuroblastoma differentiation. Three neuroblastoma cell lines (human LAN-5, human SK-N-SH, and murine N1E-115) were used in these experiments; cells from two of the lines (SK-N-SH and N1E-115) were also studied after being stably transfected with a plasmid containing a full-length DR-nm23 complementary DNA. Cellular expression of specific messenger RNAs and proteins was assessed by use of standard techniques. Cellular adhesion to a variety of protein substrates was also evaluated. DR-nm23 messenger RNA levels in nontransfected LAN-5 and SK-N-SH cells generally increased with time after exposure to differentiation-inducing conditions; levels of the other two human nm23 messenger RNAs (nm23-H1 and nm23-H2) remained essentially constant. Transfected SK-N-SH cells overexpressing DR-nm23 exhibited some characteristics of differentiated cells (increased vimentin and collagen type IV expression) even in the absence of differentiation-inducing conditions. Compared with control cells, DR-nm23-transfected cells exposed to differentiation-inducing conditions showed a greater degree of growth arrest (SK-N-SH cells) and greater increases in integrin protein expression, especially of integrin beta1 (N1E-115 cells). DR-nm23-transfected N1E-115 cells also showed a marked increase in adhesion to collagen type I-coated tissue culture plates that was inhibited by preincubation with an anti-integrin beta1 antibody. DR-nm23 gene expression appears to be associated with differentiation in neuroblastoma cells and may affect cellular adhesion through regulation of integrin protein expression.
Effect of Antibiotics against Mycoplasma sp. on Human Embryonic Stem Cells Undifferentiated Status, Pluripotency, Cell Viability and Growth

PubMed Central

Romorini, Leonardo; Riva, Diego Ariel; Blüguermann, Carolina; Videla Richardson, Guillermo Agustin; Scassa, Maria Elida; Sevlever, Gustavo Emilio; Miriuka, Santiago Gabriel

2013-01-01

Human embryonic stem cells (hESCs) are self-renewing pluripotent cells that can differentiate into specialized cells and hold great promise as models for human development and disease studies, cell-replacement therapies, drug discovery and in vitro cytotoxicity tests. The culture and differentiation of these cells are both complex and expensive, so it is essential to extreme aseptic conditions. hESCs are susceptible to Mycoplasma sp. infection, which is hard to detect and alters stem cell-associated properties. The purpose of this work was to evaluate the efficacy and cytotoxic effect of PlasmocinTM and ciprofloxacin (specific antibiotics used for Mycoplasma sp. eradication) on hESCs. Mycoplasma sp. infected HUES-5 884 (H5 884, stable hESCs H5-brachyury promoter-GFP line) cells were effectively cured with a 14 days PlasmocinTM 25 µg/ml treatment (curative treatment) while maintaining stemness characteristic features. Furthermore, cured H5 884 cells exhibit the same karyotype as the parental H5 line and expressed GFP, through up-regulation of brachyury promoter, at day 4 of differentiation onset. Moreover, H5 cells treated with ciprofloxacin 10 µg/ml for 14 days (mimic of curative treatment) and H5 and WA09 (H9) hESCs treated with PlasmocinTM 5 µg/ml (prophylactic treatment) for 5 passages retained hESCs features, as judged by the expression of stemness-related genes (TRA1-60, TRA1-81, SSEA-4, Oct-4, Nanog) at mRNA and protein levels. In addition, the presence of specific markers of the three germ layers (brachyury, Nkx2.5 and cTnT: mesoderm; AFP: endoderm; nestin and Pax-6: ectoderm) was verified in in vitro differentiated antibiotic-treated hESCs. In conclusion, we found that PlasmocinTM and ciprofloxacin do not affect hESCs stemness and pluripotency nor cell viability. However, curative treatments slightly diminished cell growth rate. This cytotoxic effect was reversible as cells regained normal growth rate upon antibiotic withdrawal. PMID:23936178
East Europe Report

DTIC Science & Technology

1987-02-19

with the original phrasing and other characteristics retained. Headlines, editorial reports, and material enclosed in brackets [] are supplied by...JPRS. Processing indicators such as [Text] or [Excerpt] in the first line of each item, or following the last line of a brief, indicate how the...phonetically or transliterated are enclosed in parentheses. Words or names preceded by a ques- tion mark and enclosed in parentheses were not clear
Latin America Report, No. 2712

DTIC Science & Technology

1983-07-26

other characteristics retained. Headlines, editorial reports, and material enclosed in brackets [] are supplied by JPRS. Processing indicators such...as [Text] or [Excerpt] in the first line of each item, or following the last line of a brief, indicate how the original information was processed ...Where no processing indicator is given, the infor- mation was summarized or extracted. Unfamiliar names rendered phonetically or transliterated are

Visualization of Endoplasmic Reticulum and Mitochondria in Aurantiochytrium limacinum by the Expression of EGFP with Cell Organelle-Specific Targeting/Retaining Signals.

PubMed

Okino, Nozomu; Wakisaka, Hiroyoshi; Ishibashi, Yohei; Ito, Makoto

2018-04-01

Thraustochytrids are single cell marine eukaryotes that produce large amounts of polyunsaturated fatty acids such as docosahexaenoic acid. In the present study, we report the visualization of endoplasmic reticulum (ER) and mitochondria in a type strain of the thraustochytrid, Aurantiochytrium limacinum ATCC MYA-1381, using the enhanced green fluorescent protein (EGFP) with specific targeting/retaining signals. We expressed the egfp gene with ER targeting/retaining signals from A. limacinum calreticulin or BiP/GRP78 in the thraustochytrid, resulting in the distribution of EGFP signals at the perinuclear region and near lipid droplets. ER-Tracker™ Red, an authentic fluorescent probe for the visualization of ER in mammalian cells, also stained the same region. We observed small lipid droplets generated from the visualized ER in the early growth phase of cell culture. Expression of the egfp gene with the mitochondria targeting signal from A. limacinum cytochrome c oxidase resulted in the localization of EGFP near the plasma membrane. The distribution of EGFP signals coincided with that of MitoTracker® Red CMXRos, which is used to visualize mitochondria in eukaryotes. The ER and mitochondria of A. limacinum were visualized for the first time by EGFP with thraustochytrid cell organelle-specific targeting/retaining signals. These results will contribute to classification of the intracellular localization of proteins expressed in ER and mitochondria as well as analyses of these cell organelles in thraustochytrids.
Microfluidic device capable of medium recirculation for non-adherent cell culture

PubMed Central

Dixon, Angela R.; Rajan, Shrinidhi; Kuo, Chuan-Hsien; Bersano, Tom; Wold, Rachel; Futai, Nobuyuki; Takayama, Shuichi; Mehta, Geeta

2014-01-01

We present a microfluidic device designed for maintenance and culture of non-adherent mammalian cells, which enables both recirculation and refreshing of medium, as well as easy harvesting of cells from the device. We demonstrate fabrication of a novel microfluidic device utilizing Braille perfusion for peristaltic fluid flow to enable switching between recirculation and refresh flow modes. Utilizing fluid flow simulations and the human promyelocytic leukemia cell line, HL-60, non-adherent cells, we demonstrate the utility of this RECIR-REFRESH device. With computer simulations, we profiled fluid flow and concentration gradients of autocrine factors and found that the geometry of the cell culture well plays a key role in cell entrapping and retaining autocrine and soluble factors. We subjected HL-60 cells, in the device, to a treatment regimen of 1.25% dimethylsulfoxide, every other day, to provoke differentiation and measured subsequent expression of CD11b on day 2 and day 4 and tumor necrosis factor-alpha (TNF-α) on day 4. Our findings display perfusion sensitive CD11b expression, but not TNF-α build-up, by day 4 of culture, with a 1:1 ratio of recirculation to refresh flow yielding the greatest increase in CD11b levels. RECIR-REFRESH facilitates programmable levels of cell differentiation in a HL-60 non-adherent cell population and can be expanded to other types of non-adherent cells such as hematopoietic stem cells. PMID:24753733
Successful immortalization of mesenchymal progenitor cells derived from human placenta and the differentiation abilities of immortalized cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang Xiaohong; Soda, Yasushi; Takahashi, Kenji

2006-12-29

We reported previously that mesenchymal progenitor cells derived from chorionic villi of the human placenta could differentiate into osteoblasts, adipocytes, and chondrocytes under proper induction conditions and that these cells should be useful for allogeneic regenerative medicine, including cartilage tissue engineering. However, similar to human mesenchymal stem cells (hMSCs), though these placental cells can be isolated easily, they are difficult to study in detail because of their limited life span in vitro. To overcome this problem, we attempted to prolong the life span of human placenta-derived mesenchymal cells (hPDMCs) by modifying hTERT and Bmi-1, and investigated whether these modified hPDMCsmore » retained their differentiation capability and multipotency. Our results indicated that the combination of hTERT and Bmi-1 was highly efficient in prolonging the life span of hPDMCs with differentiation capability to osteogenic, adipogenic, and chondrogenic cells in vitro. Clonal cell lines with directional differentiation ability were established from the immortalized parental hPDMC/hTERT + Bmi-1. Interestingly, hPDMC/Bmi-1 showed extended proliferation after long-term growth arrest and telomerase was activated in the immortal hPDMC/Bmi-1 cells. However, the differentiation potential was lost in these cells. This study reports a method to extend the life span of hPDMCs with hTERT and Bmi-1 that should become a useful tool for the study of mesenchymal stem cells.« less
Using a strengths-based approach to build caring work environments.

PubMed

Henry, Linda S; Henry, James D

2007-12-01

The current health care environment has a growing shortage of nurses and other health care professionals. Health care organizations face the twofold task of retaining employees and preventing "brain drain". A caring work environment can be instrumental in attracting and retaining productive and loyal employees, leading to increased employee and patient satisfaction and a positively impacted bottom line. A strengths-based approach powerfully and effectively promotes and nurtures a caring work environment in all health care specialties and organizations.
Silk-elastin-like protein polymer matrix for intraoperative delivery of an oncolytic vaccinia virus.

PubMed

Price, Daniel L; Li, Pingdong; Chen, Chun-Hao; Wong, Danni; Yu, Zhenkun; Chen, Nanhai G; Yu, Yong A; Szalay, Aladar A; Cappello, Joseph; Fong, Yuman; Wong, Richard J

2016-02-01

Oncolytic viral efficacy may be limited by the penetration of the virus into tumors. This may be enhanced by intraoperative application of virus immediately after surgical resection. Oncolytic vaccinia virus GLV-1h68 was delivered in silk-elastin-like protein polymer (SELP) in vitro and in vivo in anaplastic thyroid carcinoma cell line 8505c in nude mice. GLV-1h68 in SELP infected and lysed anaplastic thyroid cancer cells in vitro equally as effectively as in phosphate-buffered saline (PBS), and at 1 week retains a thousand fold greater infectious plaque-forming units. In surgical resection models of residual tumor, GLV-1h68 in SELP improves tumor control and shows increased viral β-galactosidase expression as compared to PBS. The use of SELP matrix for intraoperative oncolytic viral delivery protects infectious viral particles from degradation, facilitates sustained viral delivery and transgene expression, and improves tumor control. Such optimization of methods of oncolytic viral delivery may enhance therapeutic outcomes. © 2014 Wiley Periodicals, Inc.
Spinal Locomotor Circuits Develop Using Hierarchical Rules Based on Motorneuron Position and Identity.

PubMed

Hinckley, Christopher A; Alaynick, William A; Gallarda, Benjamin W; Hayashi, Marito; Hilde, Kathryn L; Driscoll, Shawn P; Dekker, Joseph D; Tucker, Haley O; Sharpee, Tatyana O; Pfaff, Samuel L

2015-09-02

The coordination of multi-muscle movements originates in the circuitry that regulates the firing patterns of spinal motorneurons. Sensory neurons rely on the musculotopic organization of motorneurons to establish orderly connections, prompting us to examine whether the intraspinal circuitry that coordinates motor activity likewise uses cell position as an internal wiring reference. We generated a motorneuron-specific GCaMP6f mouse line and employed two-photon imaging to monitor the activity of lumbar motorneurons. We show that the central pattern generator neural network coordinately drives rhythmic columnar-specific motorneuron bursts at distinct phases of the locomotor cycle. Using multiple genetic strategies to perturb the subtype identity and orderly position of motorneurons, we found that neurons retained their rhythmic activity-but cell position was decoupled from the normal phasing pattern underlying flexion and extension. These findings suggest a hierarchical basis of motor circuit formation that relies on increasingly stringent matching of neuronal identity and position. Copyright © 2015 Elsevier Inc. All rights reserved.
LABELING WITH 14C AMINO ACIDS OF ALBUMIN-LIKE PROTEIN BY RAT LIVER RIBONUCLEOPROTEIN PARTICLES

PubMed Central

von der Decken, Alexandra

1963-01-01

Ribonucleoprotein particles were prepared by treatment of rat liver microsomes with detergents and high concentrations of KCl. They were active in incorporating 14C amino acids into protein when incubated with cell sap together with ATP, GTP, and a system to regenerate the triphosphates. The albumin of the incubation mixture, soluble at 105,000 g, and that of the fraction released by ultrasonication of the particles were studied by immunoelectrophoresis in agar gel. When the ribonucleoprotein particles were incubated with cell sap the immunological precipitation lines formed with antiserum to rat serum albumin were highly radioactive as tested by autoradiography. After zone electrophoresis on cellulose acetate, two immunologically reactive albumins were obtained which differed in their electrophoretic mobility from rat serum albumin. Labeled albumin, when purified on DEAE-cellulose columns, retained its radioactivity as tested by autoradiography following immunoelectrophoresis. On cellulose acetate this purified albumin showed an electrophoretic mobility higher than that of rat serum albumin. PMID:14026307
Silk-elastin-like protein polymer matrix for intraoperative delivery of an oncolytic vaccinia virus

PubMed Central

Price, Daniel L.; Li, Pingdong; Chen, Chun-Hao; Wong, Danni; Yu, Zhenkun; Chen, Nanhai G.; Yu, Yong A.; Szalay, Aladar A.; Cappello, Joseph; Fong, Yuman; Wong, Richard J.

2016-01-01

Background Oncolytic viral efficacy may be limited by the penetration of the virus into tumors. This may be enhanced by intraoperative application of virus immediately after surgical resection. Methods Oncolytic vaccinia virus GLV-1h68 was delivered in silk-elastin-like protein polymer (SELP) in vitro and in vivo in anaplastic thyroid carcinoma cell line 8505c in nude mice. Results GLV-1h68 in SELP infected and lysed anaplastic thyroid cancer cells in vitro equally as effectively as in phosphate-buffered saline (PBS), and at 1 week retains a thousand fold greater infectious plaque-forming units. In surgical resection models of residual tumor, GLV-1h68 in SELP improves tumor control and shows increased viral β-galactosidase expression as compared to PBS. Conclusion The use of SELP matrix for intraoperative oncolytic viral delivery protects infectious viral particles from degradation, facilitates sustained viral delivery and transgene expression, and improves tumor control. Such optimization of methods of oncolytic viral delivery may enhance therapeutic outcomes. PMID:25244076
Memory. Engram cells retain memory under retrograde amnesia.

PubMed

Ryan, Tomás J; Roy, Dheeraj S; Pignatelli, Michele; Arons, Autumn; Tonegawa, Susumu

2015-05-29

Memory consolidation is the process by which a newly formed and unstable memory transforms into a stable long-term memory. It is unknown whether the process of memory consolidation occurs exclusively through the stabilization of memory engrams. By using learning-dependent cell labeling, we identified an increase of synaptic strength and dendritic spine density specifically in consolidated memory engram cells. Although these properties are lacking in engram cells under protein synthesis inhibitor-induced amnesia, direct optogenetic activation of these cells results in memory retrieval, and this correlates with retained engram cell-specific connectivity. We propose that a specific pattern of connectivity of engram cells may be crucial for memory information storage and that strengthened synapses in these cells critically contribute to the memory retrieval process. Copyright © 2015, American Association for the Advancement of Science.
Engram Cells Retain Memory Under Retrograde Amnesia

PubMed Central

Ryan, Tomás J.; Roy, Dheeraj S.; Pignatelli, Michele; Arons, Autumn; Tonegawa, Susumu

2017-01-01

Memory consolidation is the process by which a newly formed and unstable memory transforms into a stable long-term memory. It is unknown whether the process of memory consolidation occurs exclusively by the stabilization of memory engrams. By employing learning-dependent cell labeling, we identified an increase of synaptic strength and dendritic spine density specifically in consolidated memory engram cells. While these properties are lacking in the engram cells under protein synthesis inhibitor-induced amnesia, direct optogenetic activation of these cells results in memory retrieval, and this correlates with the retained engram cell-specific connectivity. We propose that a specific pattern of connectivity of engram cells may be crucial for memory information storage and that strengthened synapses in these cells critically contribute to the memory retrieval process. PMID:26023136
A Novel Interaction of Ecdysoneless (ECD) Protein with R2TP Complex Component RUVBL1 Is Required for the Functional Role of ECD in Cell Cycle Progression.

PubMed

Mir, Riyaz A; Bele, Aditya; Mirza, Sameer; Srivastava, Shashank; Olou, Appolinaire A; Ammons, Shalis A; Kim, Jun Hyun; Gurumurthy, Channabasavaiah B; Qiu, Fang; Band, Hamid; Band, Vimla

2015-12-28

Ecdysoneless (ECD) is an evolutionarily conserved protein whose germ line deletion is embryonic lethal. Deletion of Ecd in cells causes cell cycle arrest, which is rescued by exogenous ECD, demonstrating a requirement of ECD for normal mammalian cell cycle progression. However, the exact mechanism by which ECD regulates cell cycle is unknown. Here, we demonstrate that ECD protein levels and subcellular localization are invariant during cell cycle progression, suggesting a potential role of posttranslational modifications or protein-protein interactions. Since phosphorylated ECD was recently shown to interact with the PIH1D1 adaptor component of the R2TP cochaperone complex, we examined the requirement of ECD phosphorylation in cell cycle progression. Notably, phosphorylation-deficient ECD mutants that failed to bind to PIH1D1 in vitro fully retained the ability to interact with the R2TP complex and yet exhibited a reduced ability to rescue Ecd-deficient cells from cell cycle arrest. Biochemical analyses demonstrated an additional phosphorylation-independent interaction of ECD with the RUVBL1 component of the R2TP complex, and this interaction is essential for ECD's cell cycle progression function. These studies demonstrate that interaction of ECD with RUVBL1, and its CK2-mediated phosphorylation, independent of its interaction with PIH1D1, are important for its cell cycle regulatory function. Copyright © 2016, American Society for Microbiology. All Rights Reserved.
CAR T-cells targeting FLT3 have potent activity against FLT3-ITD+ AML and act synergistically with the FLT3-inhibitor crenolanib.

PubMed

Jetani, Hardikkumar; Garcia-Cadenas, Irene; Nerreter, Thomas; Thomas, Simone; Rydzek, Julian; Meijide, Javier Briones; Bonig, Halvard; Herr, Wolfgang; Sierra, Jordi; Einsele, Hermann; Hudecek, Michael

2018-05-01

FMS-like tyrosine kinase 3 (FLT3) is a transmembrane protein expressed on normal hematopoietic stem and progenitor cells (HSC) and retained on malignant blasts in acute myeloid leukemia (AML). We engineered CD8 + and CD4 + T-cells expressing a FLT3-specific chimeric antigen receptor (CAR) and demonstrate they confer potent reactivity against AML cell lines and primary AML blasts that express either wild-type FLT3 or FLT3 with internal tandem duplication (FLT3-ITD). We also show that treatment with the FLT3-inhibitor crenolanib leads to increased surface expression of FLT3 specifically on FLT3-ITD + AML cells and consecutively, enhanced recognition by FLT3-CAR T-cells in vitro and in vivo. As anticipated, we found that FLT3-CAR T-cells recognize normal HSCs in vitro and in vivo, and disrupt normal hematopoiesis in colony-formation assays, suggesting that adoptive therapy with FLT3-CAR T-cells will require subsequent CAR T-cell depletion and allogeneic HSC transplantation to reconstitute the hematopoietic system. Collectively, our data establish FLT3 as a novel CAR target in AML with particular relevance in high-risk FLT3-ITD + AML. Further, our data provide the first proof-of-concept that CAR T-cell immunotherapy and small molecule inhibition can be used synergistically, as exemplified by our data showing superior antileukemia efficacy of FLT3-CAR T-cells in combination with crenolanib.
A Novel Interaction of Ecdysoneless (ECD) Protein with R2TP Complex Component RUVBL1 Is Required for the Functional Role of ECD in Cell Cycle Progression

PubMed Central

Mir, Riyaz A.; Bele, Aditya; Mirza, Sameer; Srivastava, Shashank; Olou, Appolinaire A.; Ammons, Shalis A.; Kim, Jun Hyun; Gurumurthy, Channabasavaiah B.; Qiu, Fang; Band, Hamid

2015-01-01

Ecdysoneless (ECD) is an evolutionarily conserved protein whose germ line deletion is embryonic lethal. Deletion of Ecd in cells causes cell cycle arrest, which is rescued by exogenous ECD, demonstrating a requirement of ECD for normal mammalian cell cycle progression. However, the exact mechanism by which ECD regulates cell cycle is unknown. Here, we demonstrate that ECD protein levels and subcellular localization are invariant during cell cycle progression, suggesting a potential role of posttranslational modifications or protein-protein interactions. Since phosphorylated ECD was recently shown to interact with the PIH1D1 adaptor component of the R2TP cochaperone complex, we examined the requirement of ECD phosphorylation in cell cycle progression. Notably, phosphorylation-deficient ECD mutants that failed to bind to PIH1D1 in vitro fully retained the ability to interact with the R2TP complex and yet exhibited a reduced ability to rescue Ecd-deficient cells from cell cycle arrest. Biochemical analyses demonstrated an additional phosphorylation-independent interaction of ECD with the RUVBL1 component of the R2TP complex, and this interaction is essential for ECD's cell cycle progression function. These studies demonstrate that interaction of ECD with RUVBL1, and its CK2-mediated phosphorylation, independent of its interaction with PIH1D1, are important for its cell cycle regulatory function. PMID:26711270
Changes in barrier function of a model intestinal epithelium by intraepithelial lymphocytes require new protein synthesis by epithelial cells.

PubMed Central

Taylor, C T; Murphy, A; Kelleher, D; Baird, A W

1997-01-01

BACKGROUND: Elements of the mucosal immune system may play an important part in regulating epithelial barrier function in the intestinal tract. Intraepithelial lymphocytes (IELs) represent a subtype of immunocyte which is strategically placed to regulate epithelial function at most mucosal sites. AIMS AND METHODS: An IEL derived cell line (SC1) was used to examine its effects on the model epithelium T84--a tumour derived cell line which retains the phenotype of colonic crypt cells. Transepithelial electrical resistance (TER) was used as a marker of epithelial integrity. RESULTS: Coculture of T84 cells with SC1 produced a significant fall in TER as did exposure of T84 monolayers to IEL derived supernatant. Recombinant interferon-gamma (rIFN gamma) also reduced TER in T84 monolayers. Cycloheximide prevented the effects of IEL supernatant and of rIFN gamma on TER. The fall in TER in response to rIFN gamma was attenuated by blocking antibodies, which did not alter the fall in resistance induced by IEL supernatant. Fractions of IEL supernatant, separated on the basis of size, evoked temporally distinct changes in TER. Ultrastructural studies support the hypothesis that the slow onset but severe fall in TER indicates catastrophic effects on the monolayer. The more rapid onset fall in TER was not associated with gross changes in monolayer morphology. Reduction of TER by IEL supernatant was not influenced by inhibitors of tyrosine phosphatase or of protein kinase C. Although herbimycin did reduce the rapid onset change in TER, the tyrosine kinase inhibitor genistein did not alter responses to IEL supernatant. CONCLUSIONS: Mucosal T cells may influence barrier function by a process involving new protein synthesis by epithelial cells. This model may have relevance in some inflammatory conditions of the gastrointestinal tract. Images PMID:9203943
[Off-line control of runoff pollution by filtering ditch-pond system in urban tourist areas].

PubMed

Chen, Qing-Feng; Shan, Bao-Qing; Yin, Cheng-Qing; Hu, Cheng-Xiao

2007-10-01

An off-line filtering ditch-pond system for controlling storm runoff pollution in urban tourist areas was developed, which could retain the first flush effectively, resulting in the decrease of pollutant concentration and suspended solid average grain size, and the improvement of pollutant retention in runoff. This system could be an effective treatment system for storm runoff pollution, particularly for the scarcity of available land use in urban areas. In 2005, the yearly retention rates of TSS, COD, TN and TP were 86.4%, 85.5%, 83.9% and 82.9%, and during a storm event on June 26, the retention rates of runoff volume, TSS, COD, TN and TP were 67.9%, 97.0%, 89.2%, 94.9% and 96.2%, respectively. This system could also retain most of the suspended solids in runoff.
Accelerated solvent extraction by using an 'in-line' clean-up approach for multiresidue analysis of pesticides in organic honey.

PubMed

Chiesa, Luca Maria; Labella, Giuseppe Federico; Panseri, Sara; Britti, Domenico; Galbiati, Fabrizio; Villa, Roberto; Arioli, Francesco

2017-05-01

The worldwide loss of honeybee colonies may be due to their exposure to several contaminants (i.e., pesticides); such contamination may also have impacts on consumers' health. Therefore, it is essential to develop quick and new methods to detect several pesticide residues in honey samples. In this study, the effectiveness of accelerated solvent extraction (ASE) was compared with QuEChERS methods for the analysis of 53 pesticides in organic honey by gas chromatography-triple quadrupole mass spectrometry. Two simple and rapid ASE methods with 'in-line' clean-up were optimised and then compared with QuEChERS. Hexane-ethyl acetate (Hex:EtAc) and Florisil were chosen as extraction solvent and retainer for the first ASE method respectively; acetonitrile and a primary-secondary amine phase (ACN-PSA) were selected for the second ASE method. The methods were validated according to the European Union SANTE/11945/2015 guidelines. The validation parameters showed that QuEChERS and ASE with PSA as retainer had better repeatability than ASE with Hex:EtAc and Florisil. In particular, QuEChERS and ASE (ACN-PSA) showed good recovery, according to the SANTE criteria, for the majority of investigated pesticides. Conversely, when ASE with Hex:EtAc and Florisil was used as the retainer, several compounds showed recoveries lower than the acceptable value of 70%. The ASE in-line method was finally applied to evaluate pesticide concentration in organic honey samples.
Participation of the extracellular domain in (pro)renin receptor dimerization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suzuki-Nakagawa, Chiharu; Nishimura, Misa; Tsukamoto, Tomoko

Highlights: • The (pro)renin receptor [(P)RR] is a regulator of the renin–angiotensin system. • The region responsible for (P)RR dimerization was investigated. • (P)RR extracellular domain constructs were retained intracellularly. • The extracellular domain of (P)RR is responsible for its dimerization. • Novel insight into the regulatory mechanism of soluble (P)RR secretion is provided. - Abstract: The (pro)renin receptor [(P)RR] induces the catalytic activation of prorenin, as well as the activation of the mitogen-activated protein kinase (MAPK) signaling pathway; as such, it plays an important regulatory role in the renin–angiotensin system. (P)RR is known to form a homodimer, but themore » region participating in its dimerization is unknown. Using glutathione S-transferase (GST) as a carrier protein and a GST pull-down assay, we investigated the interaction of several (P)RR constructs with full-length (FL) (P)RR in mammalian cells. GST fusion proteins with FL (P)RR (GST-FL), the C-terminal M8-9 fragment (GST-M8-9), the extracellular domain (ECD) of (P)RR (GST-ECD), and the (P)RR ECD with a deletion of 32 amino acids encoded by exon 4 (GST-ECDd4) were retained intracellularly, whereas GST alone was efficiently secreted into the culture medium when transiently expressed in COS-7 cells. Immunofluorescence microscopy showed prominent localization of GST-ECD to the endoplasmic reticulum. The GST pull-down analysis revealed that GST-FL, GST-ECD, and GST-ECDd4 bound FLAG-tagged FL (P)RR, whereas GST-M8-9 showed little or no binding when transiently co-expressed in HEK293T cells. Furthermore, pull-down analysis using His-tag affinity resin showed co-precipitation of soluble (P)RR with FL (P)RR from a stable CHO cell line expressing FL h(P)RR with a C-terminal decahistidine tag. These results indicate that the (P)RR ECD participates in dimerization.« less
Purification and characterization of monoclonal antibodies to alpha-linolenic acid.

PubMed

Buffière, F; Cook-Moreau, J; Gualde, N; Rigaud, M

1989-01-01

The covalently linked antigenic complex, bovine serum albumin-alpha-linolenic acid, was used to immunize Balb/c mice against the hapten. Hybridization between splenocytes and the myeloma cell line, P 3 X63 Ag 8,651, resulted in stable clones synthesizing monoclonal antibodies (Mab) that were subsequently purified and characterized. Four Mab (A, B, C, D) were retained and their specificities studied by ELISA. Antibody D only recognized 18-carbon fatty acids having a cis,cis,-cis-1,4,7 unsaturated system in the omega-3 position: it was specific for alpha-linolenic acid. B recognized all fatty acids containing the structure cis,cis,cis-1,4,7-octatriene. A and C recognized polyunsaturated fatty acids with a degree of unsaturation superior to two double bonds.
Genetically modified pigs produced with a nonviral episomal vector

PubMed Central

Manzini, Stefano; Vargiolu, Alessia; Stehle, Isa M; Bacci, Maria Laura; Cerrito, Maria Grazia; Giovannoni, Roberto; Zannoni, Augusta; Bianco, Maria Rosaria; Forni, Monica; Donini, Pierluigi; Papa, Michele; Lipps, Hans J; Lavitrano, Marialuisa

2006-01-01

Genetic modification of cells and animals is an invaluable tool for biotechnology and biomedicine. Currently, integrating vectors are used for this purpose. These vectors, however, may lead to insertional mutagenesis and variable transgene expression and can undergo silencing. Scaffold/matrix attachment region-based vectors are nonviral expression systems that replicate autonomously in mammalian cells, thereby making possible safe and reliable genetic modification of higher eukaryotic cells and organisms. In this study, genetically modified pig fetuses were produced with the scaffold/matrix attachment region-based vector pEPI, delivered to embryos by the sperm-mediated gene transfer method. The pEPI vector was detected in 12 of 18 fetuses in the different tissues analyzed and was shown to be retained as an episome. The reporter gene encoded by the pEPI vector was expressed in 9 of 12 genetically modified fetuses. In positive animals, all tissues analyzed expressed the reporter gene; moreover in these tissues, the positive cells were on the average 79%. The high percentage of EGFP-expressing cells and the absence of mosaicism have important implications for biotechnological and biomedical applications. These results are an important step forward in animal transgenesis and can provide the basis for the future development of germ-line gene therapy. PMID:17101993
Growth promotion of genetically modified hematopoietic progenitors using an antibody/c-Mpl chimera.

PubMed

Kawahara, Masahiro; Chen, Jianhong; Sogo, Takahiro; Teng, Jinying; Otsu, Makoto; Onodera, Masafumi; Nakauchi, Hiromitsu; Ueda, Hiroshi; Nagamune, Teruyuki

2011-09-01

Thrombopoietin is a potent cytokine that exerts proliferation of hematopoietic stem cells (HSCs) through its cognate receptor, c-Mpl. Therefore, mimicry of c-Mpl signaling by a receptor recognizing an artificial ligand would be attractive to attain specific expansion of genetically modified HSCs. Here we propose a system enabling selective expansion of genetically modified cells using an antibody/receptor chimera that can be activated by a specific antigen. We constructed an antibody/c-Mpl chimera, in which single-chain Fv (ScFv) of an anti-fluorescein antibody was tethered to the extracellular D2 domain of the erythropoietin receptor and transmembrane/cytoplasmic domains of c-Mpl. When the chimera was expressed in interleukin (IL)-3-dependent pro-B cell line Ba/F3, genetically modified cells were selectively expanded in the presence of fluorescein-conjugated BSA (BSA-FL) as a specific antigen. Furthermore, highly purified mouse HSCs transduced with the retrovirus carrying antibody/c-Mpl chimera gene proliferated in vitro in response to BSA-FL, and the cells retained in vivo long-term repopulating abilities. These results demonstrate that the antibody/c-Mpl chimera is capable of signal transduction that mimics wild-type c-Mpl signaling. Copyright © 2011 Elsevier Ltd. All rights reserved.

Meiotic behavior as a selection tool in silage corn breeding.

PubMed

Souza, V F; Pagliarini, M S; Scapim, C A; Rodovalho, M; Faria, M V

2010-10-19

In breeding programs, commercial hybrids are frequently used as a source of inbred lines to obtain new hybrids. Considering that maize production is dependent on viable gametes, the selection of populations to obtain inbred lines with high meiotic stability could contribute to the formation of new silage corn hybrids adapted to specific region. We evaluated the meiotic stability of five commercial hybrids of silage corn used in southern Brazil with conventional squashing methods. All of them showed meiotic abnormalities. Some abnormalities, such as abnormal chromosome segregation and absence of cytokinesis, occurred in all the genotypes, while others, including cytomixis and abnormal spindle orientation, were found only in some genotypes. The hybrid SG6010 had the lowest mean frequency of abnormal cells (21.27%); the highest frequency was found in the hybrid P30K64 (44.43%). However, the frequency of abnormal meiotic products was much lower in most genotypes, ranging from 7.63% in the hybrid CD304 to 43.86% in Garra. Taking into account the percentage of abnormal meiotic products and, hence, meiotic stability, only the hybrids CD304, P30K64, SG6010, and P30F53 are recommended to be retained in the breeding program to obtain inbred lines to create new hybrids.
Hematopoiesis and hematopoietic organs in arthropods.

PubMed

Grigorian, Melina; Hartenstein, Volker

2013-03-01

Hemocytes (blood cells) are motile cells that move throughout the extracellular space and that exist in all clades of the animal kingdom. Hemocytes play an important role in shaping the extracellular environment and in the immune response. Developmentally, hemocytes are closely related to the epithelial cells lining the vascular system (endothelia) and the body cavity (mesothelia). In vertebrates and insects, common progenitors, called hemangioblasts, give rise to the endothelia and blood cells. In the adult animal, many differentiated hemocytes seem to retain the ability to proliferate; however, in most cases investigated closely, the bulk of hemocyte proliferation takes place in specialized hematopoietic organs. Hematopoietic organs provide an environment where undifferentiated blood stem cells are able to self-renew, and at the same time generate offspring that differentiate into different blood cell types. Hematopoiesis in vertebrates, taking place in the bone marrow, has been subject to intensive research by immunologists and stem cell biologists. Much less is known about blood cell formation in invertebrate animals. In this review, we will survey structural and functional properties of invertebrate hematopoietic organs, with a main focus on insects and other arthropod taxa. We will then discuss similarities, at the molecular and structural level, that are apparent when comparing the development of blood cells in hematopoietic organs of vertebrates and arthropods. Our comparative review is intended to elucidate aspects of the biology of blood stem cells that are more easily missed when focusing on one or a few model species.
Cell cycle-coupled expansion of AR activity promotes cancer progression.

PubMed

McNair, C; Urbanucci, A; Comstock, C E S; Augello, M A; Goodwin, J F; Launchbury, R; Zhao, S G; Schiewer, M J; Ertel, A; Karnes, J; Davicioni, E; Wang, L; Wang, Q; Mills, I G; Feng, F Y; Li, W; Carroll, J S; Knudsen, K E

2017-03-23

The androgen receptor (AR) is required for prostate cancer (PCa) survival and progression, and ablation of AR activity is the first line of therapeutic intervention for disseminated disease. While initially effective, recurrent tumors ultimately arise for which there is no durable cure. Despite the dependence of PCa on AR activity throughout the course of disease, delineation of the AR-dependent transcriptional network that governs disease progression remains elusive, and the function of AR in mitotically active cells is not well understood. Analyzing AR activity as a function of cell cycle revealed an unexpected and highly expanded repertoire of AR-regulated gene networks in actively cycling cells. New AR functions segregated into two major clusters: those that are specific to cycling cells and retained throughout the mitotic cell cycle ('Cell Cycle Common'), versus those that were specifically enriched in a subset of cell cycle phases ('Phase Restricted'). Further analyses identified previously unrecognized AR functions in major pathways associated with clinical PCa progression. Illustrating the impact of these unmasked AR-driven pathways, dihydroceramide desaturase 1 was identified as an AR-regulated gene in mitotically active cells that promoted pro-metastatic phenotypes, and in advanced PCa proved to be highly associated with development of metastases, recurrence after therapeutic intervention and reduced overall survival. Taken together, these findings delineate AR function in mitotically active tumor cells, thus providing critical insight into the molecular basis by which AR promotes development of lethal PCa and nominate new avenues for therapeutic intervention.
Wise retained in the endoplasmic reticulum inhibits Wnt signaling by reducing cell surface LRP6.

PubMed

Guidato, Sonia; Itasaki, Nobue

2007-10-15

The Wnt signaling pathway is tightly regulated by extracellular and intracellular modulators. Wise was isolated as a secreted protein capable of interacting with the Wnt co-receptor LRP6. Studies in Xenopus embryos revealed that Wise either enhances or inhibits the Wnt pathway depending on the cellular context. Here we show that the cellular localization of Wise has distinct effects on the Wnt pathway readout. While secreted Wise either synergizes or inhibits the Wnt signals depending on the partner ligand, ER-retained Wise consistently blocks the Wnt pathway. ER-retained Wise reduces LRP6 on the cell surface, making cells less susceptible to the Wnt signal. This study provides a cellular mechanism for the action of Wise and introduces the modulation of cellular susceptibility to Wnt signals as a novel mechanism of the regulation of the Wnt pathway.
Nanoparticle Delivery of miR-34a Eradicates Long-term-cultured Breast Cancer Stem Cells via Targeting C22ORF28 Directly

PubMed Central

Lin, Xiaoti; Chen, Weiyu; Wei, Fengqin; Zhou, Binhua P.; Hung, Mien-Chie; Xie, Xiaoming

2017-01-01

Rationale: Cancer stem cells (CSCs) have been implicated as the seeds of therapeutic resistance and metastasis, due to their unique abilities of self-renew, wide differentiation potentials and resistance to most conventional therapies. It is a proactive strategy for cancer therapy to eradicate CSCs. Methods: Tumor tissue-derived breast CSCs (BCSC), including XM322 and XM607, were isolated by fluorescence-activated cell sorting (FACS); while cell line-derived BCSC, including MDA-MB-231.SC and MCF-7.SC, were purified by magnetic-activated cell sorting (MACS). Analyses of microRNA and mRNA expression array profiles were performed in multiple breast cell lines. The mentioned nanoparticles were constructed following the standard molecular cloning protocol. Tissue microarray analysis has been used to study 217 cases of clinical breast cancer specimens. Results: Here, we have successfully established four long-term maintenance BCSC that retain their tumor-initiating biological properties. Our analyses of microarray and qRT-PCR explored that miR-34a is the most pronounced microRNA for investigation of BCSC. We establish hTERT promoter-driven VISA delivery of miR-34a (TV-miR-34a) plasmid that can induce high throughput of miR-34a expression in BCSC. TV-miR-34a significantly inhibited the tumor-initiating properties of long-term-cultured BCSC in vitro and reduced the proliferation of BCSC in vivo by an efficient and safe way. TV-miR-34a synergizes with docetaxel, a standard therapy for invasive breast cancer, to act as a BCSC inhibitor. Further mechanistic investigation indicates that TV-miR-34a directly prevents C22ORF28 accumulation, which abrogates clonogenicity and tumor growth and correlates with low miR-34 and high C22ORF28 levels in breast cancer patients. Conclusion: Taken together, we generated four long-term maintenance BCSC derived from either clinical specimens or cell lines, which would be greatly beneficial to the research progress in breast cancer patients. We further developed the non-viral TV-miR-34a plasmid, which has a great potential to be applied as a clinical application for breast cancer therapy. PMID:29187905
Development of Novel Patient-Derived Xenografts from Breast Cancer Brain Metastases

PubMed Central

Contreras-Zárate, María J.; Ormond, D. Ryan; Gillen, Austin E.; Hanna, Colton; Day, Nicole L.; Serkova, Natalie J.; Jacobsen, Britta M.; Edgerton, Susan M.; Thor, Ann D.; Borges, Virginia F.; Lillehei, Kevin O.; Graner, Michael W.; Kabos, Peter; Cittelly, Diana M.

2017-01-01

Brain metastases are an increasing burden among breast cancer patients, particularly for those with HER2+ and triple negative (TN) subtypes. Mechanistic insight into the pathophysiology of brain metastases and preclinical validation of therapies has relied almost exclusively on intracardiac injection of brain-homing cells derived from highly aggressive TN MDA-MB-231 and HER2+ BT474 breast cancer cell lines. Yet, these well characterized models are far from representing the tumor heterogeneity observed clinically and, due to their fast progression in vivo, their suitability to validate therapies for established brain metastasis remains limited. The goal of this study was to develop and characterize novel human brain metastasis breast cancer patient-derived xenografts (BM-PDXs) to study the biology of brain metastasis and to serve as tools for testing novel therapeutic approaches. We obtained freshly resected brain metastases from consenting donors with breast cancer. Tissue was immediately implanted in the mammary fat pad of female immunocompromised mice and expanded as BM-PDXs. Brain metastases from 3/4 (75%) TN, 1/1 (100%) estrogen receptor positive (ER+), and 5/9 (55.5%) HER2+ clinical subtypes were established as transplantable BM-PDXs. To facilitate tracking of metastatic dissemination using BM-PDXs, we labeled PDX-dissociated cells with EGFP-luciferase followed by reimplantation in mice, and generated a BM-derived cell line (F2-7). Immunohistologic analyses demonstrated that parental and labeled BM-PDXs retained expression of critical clinical markers such as ER, progesterone receptor, epidermal growth factor receptor, HER2, and the basal cell marker cytokeratin 5. Similarly, RNA sequencing analysis showed clustering of parental, labeled BM-PDXs and their corresponding cell line derivative. Intracardiac injection of dissociated cells from BM-E22-1, resulted in magnetic resonance imaging-detectable macrometastases in 4/8 (50%) and micrometastases (8/8) (100%) mice, suggesting that BM-PDXs remain capable of colonizing the brain at high frequencies. Brain metastases developed 8–12 weeks after ic injection, located to the brain parenchyma, grew around blood vessels, and elicited astroglia activation characteristic of breast cancer brain metastasis. These novel BM-PDXs represent heterogeneous and clinically relevant models to study mechanisms of brain metastatic colonization, with the added benefit of a slower progression rate that makes them suitable for preclinical testing of drugs in therapeutic settings. PMID:29164052
36 CFR 51.51 - What special terms must I know to understand leasehold surrender interest?

Code of Federal Regulations, 2010 CFR

2010-07-01

..., windows, rafters, roofing, framing, siding, lumber, insulation, wallpaper, paint, etc.). Because of their... and sewer lines) and constructed site improvements (e.g., paved roads, retaining walls, sidewalks...
36 CFR 51.51 - What special terms must I know to understand leasehold surrender interest?

Code of Federal Regulations, 2013 CFR

2013-07-01

..., windows, rafters, roofing, framing, siding, lumber, insulation, wallpaper, paint, etc.). Because of their... and sewer lines) and constructed site improvements (e.g., paved roads, retaining walls, sidewalks...
36 CFR 51.51 - What special terms must I know to understand leasehold surrender interest?

Code of Federal Regulations, 2014 CFR

2014-07-01

..., windows, rafters, roofing, framing, siding, lumber, insulation, wallpaper, paint, etc.). Because of their... and sewer lines) and constructed site improvements (e.g., paved roads, retaining walls, sidewalks...
36 CFR 51.51 - What special terms must I know to understand leasehold surrender interest?

Code of Federal Regulations, 2012 CFR

2012-07-01

..., windows, rafters, roofing, framing, siding, lumber, insulation, wallpaper, paint, etc.). Because of their... and sewer lines) and constructed site improvements (e.g., paved roads, retaining walls, sidewalks...
36 CFR 51.51 - What special terms must I know to understand leasehold surrender interest?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., windows, rafters, roofing, framing, siding, lumber, insulation, wallpaper, paint, etc.). Because of their... and sewer lines) and constructed site improvements (e.g., paved roads, retaining walls, sidewalks...
Chemical modification of birch allergen extract leads to a reduction in allergenicity as well as immunogenicity.

PubMed

Würtzen, Peter Adler; Lund, Lise; Lund, Gitte; Holm, Jens; Millner, Anders; Henmar, Helene

2007-01-01

In Europe, specific immunotherapy is currently conducted with vaccines containing allergen preparations based on intact extracts. In addition to this, chemically modified allergen extracts (allergoids) are used for specific allergy treatment. Reduced allergenicity and thereby reduced risk of side effects in combination with retained ability to activate T cells and induce protective allergen-specific antibody responses has been claimed for allergoids. In the current study, we compared intact allergen extracts and allergoids with respect to allergenicity and immunogenicity. The immunological response to birch allergen extract, alum-adsorbed extract, birch allergoid and alum-adsorbed allergoid was investigated in vitro in human basophil histamine release assay and by stimulation of human allergen-specific T cell lines. In vivo, Bet v 1-specific IgG titers in mice were determined after repetitive immunizations. In all patients tested (n = 8), allergoid stimulations led to reduced histamine release compared to the intact allergen extract. However, the allergoid preparations were not recognized by Bet v 1-specific T cell lines (n = 7), which responded strongly to the intact allergen extract. Mouse immunizations showed a clearly reduced IgG induction by allergoids and a strongly potentiating effect of the alum adjuvant. Optimal IgG titers were obtained after 3 immunizations with intact allergen extracts, while 5 immunizations were needed to obtain maximal response to the allergoid. The reduced histamine release observed for allergoid preparations may be at the expense of immunological efficacy because the chemical modifications lead to a clear reduction in T cell activation and the ability to induce allergen-specific IgG antibody responses. Copyright 2007 S. Karger AG, Basel.
Alternative Splicing and Caspase-Mediated Cleavage Generate Antagonistic Variants of the Stress Oncoprotein LEDGF/p75

PubMed Central

Brown-Bryan, Terry A.; Leoh, Lai S.; Ganapathy, Vidya; Pacheco, Fabio J.; Mediavilla-Varela, Melanie; Filippova, Maria; Linkhart, Thomas A.; Gijsbers, Rik; Debyser, Zeger; Casiano, Carlos A.

2009-01-01

There is increasing evidence that an augmented state of cellular oxidative stress modulates the expression of stress genes implicated in diseases associated with health disparities such as certain cancers and diabetes. Lens epithelium–derived growth factor p75 (LEDGF/p75), also known as DFS70 autoantigen, is emerging as a survival oncoprotein that promotes resistance to oxidative stress–induced cell death and chemotherapy. We previously showed that LEDGF/p75 is targeted by autoantibodies in prostate cancer patients and is overexpressed in prostate tumors, and that its stress survival activity is abrogated during apoptosis. LEDGF/p75 has a COOH-terminally truncated splice variant, p52, whose role in stress survival and apoptosis has not been thoroughly investigated. We observed unbalanced expression of these proteins in a panel of tumor cell lines, with LEDGF/p75 generally expressed at higher levels. During apoptosis, caspase-3 cleaved p52 to generate a p38 fragment that lacked the NH2-terminal PWWP domain and failed to transactivate the Hsp27 promoter in reporter assays. However, p38 retained chromatin association properties and repressed the transactivation potential of LEDGF/p75. Overexpression of p52 or its variants with truncated PWWP domains in several tumor cell lines induced apoptosis, an activity that was linked to the presence of an intron-derived COOH-terminal sequence. These results implicate the PWWP domain of p52 in transcription function but not in chromatin association and proapoptotic activities. Consistent with their unbalanced expression in tumor cells, LEDGF/p75 and p52 seem to play antagonistic roles in the cellular stress response and could serve as targets for novel antitumor therapies. PMID:18708362
Slow-cycling stem cells in hydra contribute to head regeneration

PubMed Central

Govindasamy, Niraimathi; Murthy, Supriya; Ghanekar, Yashoda

2014-01-01

ABSTRACT Adult stem cells face the challenge of maintaining tissue homeostasis by self-renewal while maintaining their proliferation potential over the lifetime of an organism. Continuous proliferation can cause genotoxic/metabolic stress that can compromise the genomic integrity of stem cells. To prevent stem cell exhaustion, highly proliferative adult tissues maintain a pool of quiescent stem cells that divide only in response to injury and thus remain protected from genotoxic stress. Hydra is a remarkable organism with highly proliferative stem cells and ability to regenerate at whole animal level. Intriguingly, hydra does not display consequences of high proliferation, such as senescence or tumour formation. In this study, we investigate if hydra harbours a pool of slow-cycling stem cells that could help prevent undesirable consequences of continuous proliferation. Hydra were pulsed with the thymidine analogue 5-ethynyl-2′-deoxyuridine (EdU) and then chased in the absence of EdU to monitor the presence of EdU-retaining cells. A significant number of undifferentiated cells of all three lineages in hydra retained EdU for about 8–10 cell cycles, indicating that these cells did not enter cell cycle. These label-retaining cells were resistant to hydroxyurea treatment and were predominantly in the G2 phase of cell cycle. Most significantly, similar to mammalian quiescent stem cells, these cells rapidly entered cell division during head regeneration. This study shows for the first time that, contrary to current beliefs, cells in hydra display heterogeneity in their cell cycle potential and the slow-cycling cells in this population enter cell cycle during head regeneration. These results suggest an early evolution of slow-cycling stem cells in multicellular animals. PMID:25432513
Backbone modified TBA analogues endowed with antiproliferative activity.

PubMed

Esposito, Veronica; Russo, Annapina; Amato, Teresa; Varra, Michela; Vellecco, Valentina; Bucci, Mariarosaria; Russo, Giulia; Virgilio, Antonella; Galeone, Aldo

2017-05-01

The thrombin binding aptamer (TBA) is endowed with antiproliferative properties but its potential development is counteracted by the concomitant anticoagulant activity. Five oligonucleotides (ODNs) based on TBA sequence (GGTTGGTGTGGTTGG) and containing l-residues or both l-residues and inversion of polarity sites have been investigated by NMR and CD techniques for their ability to form G-quadruplex structures. Furthermore, their anticoagulant (PT assay) and antiproliferative properties (MTT assay), and their resistance in fetal bovine serum have been tested. CD and NMR data suggest that the investigated ODNs are able to form right- and left-handed G-quadruplex structures. All ODNs do not retain the anticoagulant activity characteristic of TBA but are endowed with a significant antiproliferative activity against two cancerous cell lines. Their resistance in biological environment after six days is variable, depending on the ODN. A comparison between results and literature data suggests that the antiproliferative activity of the TBA analogues investigated could depends on two factors: a) biological pathways and targets different from those already identified or proposed for other antiproliferative G-quadruplex aptamers, and b) the contribution of the guanine-based degradation products. Modified TBA analogues containing l-residues and inversion of polarity sites lose the anticoagulant activity but gain antiproliferative properties against two cancer cell lines. This article is part of a Special Issue entitled "G-quadruplex" Guest Editor: Dr. Concetta Giancola and Dr. Daniela Montesarchio. Copyright © 2016 Elsevier B.V. All rights reserved.
Aloe vera Induced Biomimetic Assemblage of Nucleobase into Nanosized Particles

PubMed Central

Chauhan, Arun; Zubair, Swaleha; Sherwani, Asif; Owais, Mohammad

2012-01-01

Aim Biomimetic nano-assembly formation offers a convenient and bio friendly approach to fabricate complex structures from simple components with sub-nanometer precision. Recently, biomimetic (employing microorganism/plants) synthesis of metal and inorganic materials nano-particles has emerged as a simple and viable strategy. In the present study, we have extended biological synthesis of nano-particles to organic molecules, namely the anticancer agent 5-fluorouracil (5-FU), using Aloe vera leaf extract. Methodology The 5-FU nano- particles synthesized by using Aloe vera leaf extract were characterized by UV, FT-IR and fluorescence spectroscopic techniques. The size and shape of the synthesized nanoparticles were determined by TEM, while crystalline nature of 5-FU particles was established by X-ray diffraction study. The cytotoxic effects of 5-FU nanoparticles were assessed against HT-29 and Caco-2 (human adenocarcinoma colorectal) cell lines. Results Transmission electron microscopy and atomic force microscopic techniques confirmed nano-size of the synthesized particles. Importantly, the nano-assembled 5-FU retained its anticancer action against various cancerous cell lines. Conclusion In the present study, we have explored the potential of biomimetic synthesis of nanoparticles employing organic molecules with the hope that such developments will be helpful to introduce novel nano-particle formulations that will not only be more effective but would also be devoid of nano-particle associated putative toxicity constraints. PMID:22403622
Diabetes Insipidus in Mice with a Mutation in Aquaporin-2

PubMed Central

Lloyd, David J; Hall, Frank Wesley; Tarantino, Lisa M; Gekakis, Nicholas

2005-01-01

Congenital nephrogenic diabetes insipidus (NDI) is a disease characterized by failure of the kidney to concentrate urine in response to vasopressin. Human kindreds with nephrogenic diabetes insipidus have been found to harbor mutations in the vasopressin receptor 2 (Avpr2) gene or the vasopressin-sensitive water channel aquaporin-2 (Aqp2) gene. Development of a treatment is rendered difficult due to the lack of a viable animal model. Through forward genetic screening of ethylnitrosourea-mutagenized mice, we report the identification and characterization of a mouse model of NDI, with an F204V mutation in the Aqp2 gene. Unlike previously attempted murine models of NDI, our mice survive to adulthood and more exactly recapitulate the human disorder. Previous in vitro experiments using renal cell lines suggest recessive Aqp2 mutations result in improper trafficking of the mutant water pore. Using these animals, we have directly proven this hypothesis of improper AQP2 translocation as the molecular defect in nephrogenic diabetes insipidus in the intact organism. Additionally, using a renal cell line we show that the mutated protein, AQP2-F204V, is retained in the endoplasmic reticulum and that this abnormal localization can be rescued by wild-type protein. This novel mouse model allows for further mechanistic studies as well as testing of pharmacological and gene therapies for NDI. PMID:16121255
A Synergism between Adaptive Effects and Evolvability Drives Whole Genome Duplication to Fixation

PubMed Central

Cuypers, Thomas D.; Hogeweg, Paulien

2014-01-01

Whole genome duplication has shaped eukaryotic evolutionary history and has been associated with drastic environmental change and species radiation. While the most common fate of WGD duplicates is a return to single copy, retained duplicates have been found enriched for highly interacting genes. This pattern has been explained by a neutral process of subfunctionalization and more recently, dosage balance selection. However, much about the relationship between environmental change, WGD and adaptation remains unknown. Here, we study the duplicate retention pattern postWGD, by letting virtual cells adapt to environmental changes. The virtual cells have structured genomes that encode a regulatory network and simple metabolism. Populations are under selection for homeostasis and evolve by point mutations, small indels and WGD. After populations had initially adapted fully to fluctuating resource conditions re-adaptation to a broad range of novel environments was studied by tracking mutations in the line of descent. WGD was established in a minority (≈30%) of lineages, yet, these were significantly more successful at re-adaptation. Unexpectedly, WGD lineages conserved more seemingly redundant genes, yet had higher per gene mutation rates. While WGD duplicates of all functional classes were significantly over-retained compared to a model of neutral losses, duplicate retention was clearly biased towards highly connected TFs. Importantly, no subfunctionalization occurred in conserved pairs, strongly suggesting that dosage balance shaped retention. Meanwhile, singles diverged significantly. WGD, therefore, is a powerful mechanism to cope with environmental change, allowing conservation of a core machinery, while adapting the peripheral network to accommodate change. PMID:24743268
A synergism between adaptive effects and evolvability drives whole genome duplication to fixation.

PubMed

Cuypers, Thomas D; Hogeweg, Paulien

2014-04-01

Whole genome duplication has shaped eukaryotic evolutionary history and has been associated with drastic environmental change and species radiation. While the most common fate of WGD duplicates is a return to single copy, retained duplicates have been found enriched for highly interacting genes. This pattern has been explained by a neutral process of subfunctionalization and more recently, dosage balance selection. However, much about the relationship between environmental change, WGD and adaptation remains unknown. Here, we study the duplicate retention pattern postWGD, by letting virtual cells adapt to environmental changes. The virtual cells have structured genomes that encode a regulatory network and simple metabolism. Populations are under selection for homeostasis and evolve by point mutations, small indels and WGD. After populations had initially adapted fully to fluctuating resource conditions re-adaptation to a broad range of novel environments was studied by tracking mutations in the line of descent. WGD was established in a minority (≈30%) of lineages, yet, these were significantly more successful at re-adaptation. Unexpectedly, WGD lineages conserved more seemingly redundant genes, yet had higher per gene mutation rates. While WGD duplicates of all functional classes were significantly over-retained compared to a model of neutral losses, duplicate retention was clearly biased towards highly connected TFs. Importantly, no subfunctionalization occurred in conserved pairs, strongly suggesting that dosage balance shaped retention. Meanwhile, singles diverged significantly. WGD, therefore, is a powerful mechanism to cope with environmental change, allowing conservation of a core machinery, while adapting the peripheral network to accommodate change.
Characterization of a family of structurally related glycoproteins expressing beta 1-6-branched asparagine-linked oligosaccharides in human colon carcinoma cells.

PubMed Central

Laferté, S; Loh, L C

1992-01-01

Previous studies have established that metastatic tumour cells express high levels of beta 1-6-branched Asn-linked oligosaccharides which can be detected with the lectin leucoagglutinin (L-PHA) [Dennis, Laferté, Waghorne, Breitman & Kerbel (1987) Science 236, 582-585]. In order to identify L-PHA-binding glycoproteins which may play a role specifically in colon cancer, we have prepared monoclonal antibodies (MAbs) to the moderately well-differentiated human colon carcinoma cell line HT29. In this paper we present the initial characterization of a family of structurally related L-PHA-binding glycoproteins detected by MAb 1H9 which are differentially expressed and processed by HT29 cells and by two other human colon carcinoma cell lines, SW480 and SW620. In contrast to HT29, the SW480 and SW620 cell lines were established from a poorly differentiated grade III/IV primary tumour and one of its lymph node metastases respectively. MAb 1H9 detects in HT29 cells a conformational determinant present on three L-PHA-binding glycoproteins of 100, 70 and 25kDa, as well as a 74 kDa glycoprotein with high-mannose-type Asn-linked oligosaccharides. Pulse-chase experiments and peptide mapping analyses revealed that the 74 kDa and 100 kDa species are related by carbohydrate processing and are probably derived from a common 76 kDa precursor. On the other hand, the 70 kDa glycoprotein is synthesized from an endoglycosidase H-sensitive precursor of 56 kDa which is structurally related to, but distinct from, the aforementioned 76 kDa precursor. In addition, the 100 kDa species is secreted into the culture medium, whereas the 70 kDa glycoprotein is retained intracellularly. SW480 and SW620 cells showed qualitative and quantitative differences from HT29 cells, including increased secretion of a smaller L-PHA-binding glycoprotein of 92 kDa into the culture medium, as well as apparent differences in glycosylation of the intracellular 66 kDa glycoprotein. These results suggested that the expression, glycosylation and subcellular localization of this family of L-PHA-binding glycoproteins may correlate with the differentiation status of colon cancer cells and/or reflect biochemical changes. characteristic of more progressive metastatic tumours. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. Fig. 8. Fig. 9. Fig. 10. PMID:1567368

Differential Sensitivities of Fast- and Slow-Cycling Cancer Cells to Inosine Monophosphate Dehydrogenase 2 Inhibition by Mycophenolic Acid

PubMed Central

Chen, Kan; Cao, Wanlu; Li, Juan; Sprengers, Dave; Hernanda, Pratika Y; Kong, Xiangdong; van der Laan, Luc JW; Man, Kwan; Kwekkeboom, Jaap; Metselaar, Herold J; Peppelenbosch, Maikel P; Pan, Qiuwei

2015-01-01

As uncontrolled cell proliferation requires nucleotide biosynthesis, inhibiting enzymes that mediate nucleotide biosynthesis constitutes a rational approach to the management of oncological diseases. In practice, however, results of this strategy are mixed and thus elucidation of the mechanisms by which cancer cells evade the effect of nucleotide biosynthesis restriction is urgently needed. Here we explored the notion that intrinsic differences in cancer cell cycle velocity are important in the resistance toward inhibition of inosine monophosphate dehydrogenase (IMPDH) by mycophenolic acid (MPA). In short-term experiments, MPA treatment of fast-growing cancer cells effectively elicited G0/G1 arrest and provoked apoptosis, thus inhibiting cell proliferation and colony formation. Forced expression of a mutated IMPDH2, lacking a binding site for MPA but retaining enzymatic activity, resulted in complete resistance of cancer cells to MPA. In nude mice subcutaneously engrafted with HeLa cells, MPA moderately delayed tumor formation by inhibiting cell proliferation and inducing apoptosis. Importantly, we developed a lentiviral vector–based Tet-on label-retaining system that enables to identify, isolate and functionally characterize slow-cycling or so-called label-retaining cells (LRCs) in vitro and in vivo. We surprisingly found the presence of LRCs in fast-growing tumors. LRCs were superior in colony formation, tumor initiation and resistance to MPA as compared with fast-cycling cells. Thus, the slow-cycling compartment of cancer seems predominantly responsible for resistance to MPA. PMID:26467706
An in-vitro scaffold-free epithelial-fibroblast coculture model for the larynx

PubMed Central

Walimbe, Tanaya; Panitch, Alyssa; Sivasankar, M. Preeti

2017-01-01

Objective Physiologically relevant, well-characterized in vitro vocal fold coculture models are needed to test the effects of various challenges and therapeutics on vocal fold physiology. We characterize a healthy state coculture model, created by using bronchial/tracheal epithelial cells and immortalized vocal fold fibroblasts. We also demonstrate that this model can be induced into a fibroplastic state to overexpress stress fibers using TGFβ1. Method Cell metabolic activity of immortalized human vocal fold fibroblasts incubated in different media combinations were confirmed with MTT assay. Fibroblasts were grown to confluence and primary bronchial/tracheal epithelial cells suspended in coculture media were seeded directly over the base layer of the fibroblasts. Cells were treated with TGFβ1 to induce myofibroblast formation. Cell shape and position was confirmed by live cell tracking, fibrosis was confirmed by probing for α smooth muscle actin (α-SMA) and phenotype was confirmed by immunostaining for vimentin and E-cadherin. Results Fibroblasts retain metabolic activity in coculture epithelial media. Live cell imaging revealed a layer of epithelial cells atop fibroblasts. α-SMA expression was enhanced in TGFβ1 treated cells, confirming that both cell types maintained a healthy phenotype in coculture, and can be induced into overexpressing stress fibers. Vimentin and E-cadherin immunostaining show that cells retain phenotype in coculture. Conclusion These data lay effective groundwork for a functional coculture model that retains the reproducibility necessary to serve as a viable diagnostic and therapeutic screening platform. Level of Evidence NA PMID:27859361
Mesenchymal Stem Cell Spheroids Retain Osteogenic Phenotype Through α2β1 Signaling

PubMed Central

Murphy, Kaitlin C.; Hoch, Allison I.; Harvestine, Jenna N.; Zhou, Dejie

2016-01-01

The induction of mesenchymal stem cells (MSCs) toward the osteoblastic lineage using osteogenic supplements prior to implantation is one approach under examination to enhance their bone-forming potential. MSCs rapidly lose their induced phenotype upon removal of the soluble stimuli; however, their bone-forming potential can be sustained when provided with continued instruction via extracellular matrix (ECM) cues. In comparison with dissociated cells, MSC spheroids exhibit improved survival and secretion of trophic factors while maintaining their osteogenic potential. We hypothesized that entrapment of MSC spheroids formed from osteogenically induced cells would exhibit better preservation of their bone-forming potential than would dissociated cells from monolayer culture. Spheroids exhibited comparable osteogenic potential and increased proangiogenic potential with or without osteogenic preconditioning versus monolayer-cultured MSCs. Spheroids were then entrapped in collagen hydrogels, and the osteogenic stimulus was removed. In comparison with entrapped dissociated MSCs, spheroids exhibited significantly increased markers of osteogenic differentiation. The capacity of MSC spheroids to retain their osteogenic phenotype upon withdrawal of inductive cues was mediated by α2β1 integrin binding to cell-secreted ECM. These results demonstrate the capacity of spheroidal culture to sustain the mineral-producing phenotype of MSCs, thus enhancing their contribution toward bone formation and repair. Significance Despite the promise of mesenchymal stem cells (MSCs) for cell-based therapies for tissue repair and regeneration, there is little evidence that transplanted MSCs directly contribute to new bone formation, suggesting that induced cells rapidly lose their osteogenic phenotype or undergo apoptosis. In comparison with dissociated cells, MSC spheroids exhibit increased trophic factor secretion and improved cell survival. The loss of phenotype represents a significant clinical challenge for cell therapies, yet there is no evidence for whether MSC spheroids retain their osteogenic phenotype upon entrapment in a clinically relevant biomaterial. These findings demonstrate that MSC spheroids retain their osteogenic phenotype better than do dissociated MSCs, and this is due to integrin engagement with the cell-secreted extracellular matrix. These data provide evidence for a novel approach for potentiating the use of MSCs in bone repair. PMID:27365484
The transcription factor Olig2 is important for the biology of diffuse intrinsic pontine gliomas.

PubMed

Anderson, Jane L; Muraleedharan, Ranjithmenon; Oatman, Nicole; Klotter, Amanda; Sengupta, Satarupa; Waclaw, Ronald R; Wu, Jianqiang; Drissi, Rachid; Miles, Lili; Raabe, Eric H; Weirauch, Matthew L; Fouladi, Maryam; Chow, Lionel M; Hoffman, Lindsey; DeWire, Mariko; Dasgupta, Biplab

2017-08-01

Diffuse intrinsic pontine glioma (DIPG) is a high-grade brainstem glioma of children with dismal prognosis. There is no single unifying model about the cell of origin of DIPGs. Proliferating cells in the developing human and mouse pons, the site of DIPGs, express neural stem/progenitor cell (NPC) markers, including Sox2, nestin, vimentin, Olig2, and glial fibrillary acidic protein, in an overlapping and non-overlapping manner, suggesting progenitor cell heterogeneity in the pons. It is thought that during a restricted window of postnatal pons development, a differentiation block caused by genetic/epigenetic changes leads to unrestrained progenitor proliferation and DIPG development. Nearly 80% of DIPGs harbor a mutation in the H3F3A or the related HIST1H3B gene. Supporting the impaired differentiation model, NPCs derived from human induced pluripotent stem cells expressing the H3F3A mutation showed complete differentiation block. However, the mechanisms regulating an altered differentiation program in DIPG are unknown. We established syngeneic serum-dependent and independent primary DIPG lines, performed molecular characterization of DIPG lines in vitro and in an orthotopic xenograft model, and used small hairpin RNA to examine Olig2 function in DIPG. The transcription factor Olig2 is highly expressed in 70%-80% of DIPGs. Here we report that Olig2 expression and DIPG differentiation are mutually exclusive events in vitro, and only DIPG cells that retained Olig2 in vitro formed robust Olig2-positive brainstem glioma with 100% penetrance in a xenograft model. Our results indicate Olig2 as an onco-requisite factor in DIPG and propose investigation of Olig2 target genes as novel candidates in DIPG therapy. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com
Placenta-specific1 (PLAC1) is a potential target for antibody-drug conjugate-based prostate cancer immunotherapy.

PubMed

Nejadmoghaddam, Mohammad-Reza; Zarnani, Amir-Hassan; Ghahremanzadeh, Ramin; Ghods, Roya; Mahmoudian, Jafar; Yousefi, Maryam; Nazari, Mahboobeh; Ghahremani, Mohammad Hossein; Abolhasani, Maryam; Anissian, Ali; Mahmoudi, Morteza; Dinarvand, Rassoul

2017-10-17

Our recent findings strongly support the idea of PLAC1 being as a potential immunotherapeutic target in prostate cancer (PCa). Here, we have generated and evaluated an anti-placenta-specific1 (PLAC1)-based antibody drug conjugate (ADC) for targeted immunotherapy of PCa. Prostate cancer cells express considerable levels of PLAC1. The Anti-PLAC1 clone, 2H12C12, showed high reactivity with recombinant PLAC1 and selectivity recognized PLAC1 in prostate cancer cells but not in LS180 cells, the negative control. PLAC1 binding induced rapid internalization of the antibody within a few minutes which reached to about 50% after 15 min and almost completed within an hour. After SN38 conjugation to antibody, a drug-antibody ratio (DAR) of about 5.5 was achieved without apparent negative effect on antibody affinity to cell surface antigen. The ADC retained intrinsic antibody activity and showed enhanced and selective cytotoxicity with an IC50 of 62 nM which was about 15-fold lower compared to free drug. Anti-PLAC1-ADC induced apoptosis in human primary prostate cancer cells and prostate cell lines. No apparent cytotoxic effect was observed in in vivo animal safety experiments. Our newly developed anti-PLAC1-based ADCs might pave the way for a reliable, efficient, and novel immunotherapeutic modality for patients with PCa.
Engineered Interleukin-2 Antagonists for the Inhibition of Regulatory T cells

PubMed Central

Liu, David V.; Maier, Lisa M.; Hafler, David A.; Wittrup, K. Dane

2014-01-01

The immunosuppressive effects of CD4+ CD25high regulatory T cells interfere with anti-tumor immune responses in cancer patients. Here, we present a novel class of engineered human Interleukin (IL)-2 analogues that antagonize the IL-2 receptor, for inhibiting regulatory T cell suppression. These antagonists have been engineered for high affinity to the α subunit of the IL-2 receptor and very low affinity to either the β or γ subunit, resulting in a signaling-deficient IL-2 analogue that sequesters the IL-2 receptor α subunit from wild type IL-2. Two variants, “V91R” and “Q126T” with residue substitutions that disrupt the β and γ subunit binding interfaces, respectively, have been characterized in both a T cell line and in human primary regulatory T cells. These mutants retain their high affinity binding to IL-2 receptor α subunit, but do not activate STAT5 phosphorylation or stimulate T cell growth. The two mutants competitively antagonize wild-type IL-2 signaling through the IL-2 receptor with similar efficacy, with inhibition constants of 183 pM for V91R and 216 pM for Q126T. Here, we present a novel approach to CD25-mediated Treg inhibition, with the use of an engineered human IL-2 analogue that antagonizes the IL-2 receptor. PMID:19816193
Shaped superconductor cylinder retains intense magnetic field

NASA Technical Reports Server (NTRS)

Hildebrandt, A. F.; Wahlquist, H.

1964-01-01

The curve of the inner walls of a superconducting cylinder is plotted from the flux lines of the magnetic field to be contained. This shaping reduces maximum flux densities and permits a stronger and more uniform magnetic field.
Geotechnical Asset Management Plan : Technical Report

DOT National Transportation Integrated Search

2017-06-30

Geotechnical assets which include rock and soil slopes, retaining walls, and material sites support and protect the Department's pavements and bridges, and provide the material from which these assets are built. They are the front line of the...
A glial cell line-derived neurotrophic factor (GDNF):tetanus toxin fragment C protein conjugate improves delivery of GDNF to spinal cord motor neurons in mice.

PubMed

Larsen, Kristin E; Benn, Susanna C; Ay, Ilknur; Chian, Ru-Ju; Celia, Samuel A; Remington, Mary P; Bejarano, Michelle; Liu, Meiqin; Ross, Joshua; Carmillo, Paul; Sah, Dinah; Phillips, Kester A; Sulzer, David; Pepinsky, R Blake; Fishman, Paul S; Brown, Robert H; Francis, Jonathan W

2006-11-20

Glial cell line-derived neurotrophic factor (GDNF) has shown robust neuroprotective and neuroreparative activities in various animal models of Parkinson's Disease or amyotrophic lateral sclerosis (ALS). The successful use of GDNF as a therapeutic in humans, however, appears to have been hindered by its poor bioavailability to target neurons in the central nervous system (CNS). To improve delivery of exogenous GDNF protein to CNS motor neurons, we employed chemical conjugation techniques to link recombinant human GDNF to the neuronal binding fragment of tetanus toxin (tetanus toxin fragment C, or TTC). The predominant species present in the purified conjugate sample, GDNF:TTC, had a molecular weight of approximately 80 kDa as determined by non-reducing SDS-PAGE. Like GDNF, addition of GDNF:TTC to culture media of neuroblastoma cells expressing GFRalpha-1/c-RET produced a dose-dependent increase in cellular phospho-c-RET levels. Treatment of cultured midbrain dopaminergic neurons with either GDNF or the conjugate similarly promoted both DA neuron survival and neurite outgrowth. However, in contrast to mice treated with GDNF by intramuscular injection, mice receiving GDNF:TTC revealed intense GDNF immunostaining associated with spinal cord motor neurons in fixed tissue sections. That GDNF:TTC provided neuroprotection of axotomized motor neurons in neonatal rats further revealed that the conjugate retained its GDNF activity in vivo. These results indicate that TTC can serve as a non-viral vehicle to substantially improve the delivery of functionally active growth factors to motor neurons in the mammalian CNS.
The Aorta-Gonad-Mesonephros Organ Culture Recapitulates 5hmC Reorganization and Replication-Dependent and Independent Loss of DNA Methylation in the Germline.

PubMed

Calvopina, Joseph Hargan; Cook, Helene; Vincent, John J; Nee, Kevin; Clark, Amander T

2015-07-01

Removal of cytosine methylation from the genome is critical for reprogramming and transdifferentiation and plays a central role in our understanding of the fundamental principles of embryo lineage development. One of the major models for studying cytosine demethylation is the mammalian germ line during the primordial germ cell (PGC) stage of embryo development. It is now understood that oxidation of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) is required to remove cytosine methylation in a locus-specific manner in PGCs; however, the mechanisms downstream of 5hmC are controversial and hypothesized to involve either active demethylation or replication-coupled loss. In the current study, we used the aorta-gonad-mesonephros (AGM) organ culture model to show that this model recapitulates germ line reprogramming, including 5hmC reorganization and loss of cytosine methylation from Snrpn and H19 imprinting control centers (ICCs). To directly address the hypothesis that cell proliferation is required for cytosine demethylation, we blocked PI3-kinase-dependent PGC proliferation and show that this leads to a G1 and G2/M cell cycle arrest in PGCs, together with retained levels of cytosine methylation at the Snrpn ICC, but not at the H19 ICC. Taken together, the AGM organ culture model is an important tool to evaluate mechanisms of locus-specific demethylation and the role of PI3-kinase-dependent PGC proliferation in the locus-specific removal of cytosine methylation from the genome.
Balancing Cell Migration with Matrix Degradation Enhances Gene Delivery to Cells Cultured Three-Dimensionally Within Hydrogels

PubMed Central

Shepard, Jaclyn A.; Huang, Alyssa; Shikanova, Ariella; Shea, Lonnie D.

2010-01-01

In regenerative medicine, hydrogels are employed to fill defects and support the infiltration of cells that can ultimately regenerate tissue. Gene delivery within hydrogels targeting infiltrating cells has the potential to promote tissue formation, but the delivery efficiency of nonviral vectors within hydrogels is low hindering their applicability in tissue regeneration. To improve their functionality, we have conducted a mechanistic study to investigate the contribution of cell migration and matrix degradation on gene delivery. In this report, lipoplexes were entrapped within hydrogels based on poly(ethylene glycol) (PEG) crosslinked with peptides containing matrix metalloproteinase degradable sequences. The mesh size of these hydrogels is substantially less than the size of the entrapped lipoplexes, which can function to retain vectors. Cell migration and transfection were simultaneously measured within hydrogels with varying density of cell adhesion sites (Arg-Gly-Asp peptides) and solids content. Increasing RGD density increased expression levels up to 100-fold, while greater solids content sustained expression levels for 16 days. Increasing RGD density and decreasing solids content increased cell migration, which indicates expression levels increase with increased cell migration. Initially exposing cells to vector resulted in transient expression that declined after 2 days, verifying the requirement of migration to sustain expression. Transfected cells were predominantly located within the population of migrating cells for hydrogels that supported cell migration. Although the small mesh size retained at least 70% of the lipoplexes in the absence of cells after 32 days, the presence of cells decreased retention to 10% after 16 days. These results indicate that vectors retained within hydrogels contact migrating cells, and that persistent cell migration can maintain elevated expression levels. Thus matrix degradation and cell migration are fundamental design parameters for maximizing gene delivery from hydrogels. PMID:20450944
In vitro atrazine-exposure inhibits human natural killer cell lytic granule release

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rowe, Alexander M.; Brundage, Kathleen M.; Center for Immunopathology and Microbial Pathogenesis, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV 26506

2007-06-01

The herbicide atrazine is a known immunotoxicant and an inhibitor of human natural killer (NK) cell lytic function. The precise changes in NK cell lytic function following atrazine exposure have not been fully elucidated. The current study identifies the point at which atrazine exerts its affect on the stepwise process of human NK cell-mediated lyses of the K562 target cell line. Using intracellular staining of human peripheral blood lymphocytes, it was determined that a 24-h in vitro exposure to atrazine did not decrease the level of NK cell lytic proteins granzyme A, granzyme B or perforin. Thus, it was hypothesizedmore » that atrazine exposure was inhibiting the ability of the NK cells to bind to the target cell and subsequently inhibit the release of lytic protein from the NK cell. To test this hypothesis, flow cytometry and fluorescent microscopy were employed to analyze NK cell-target cell co-cultures following atrazine exposure. These assays demonstrated no significant decrease in the level of target cell binding. However, the levels of NK intracellular lytic protein retained and the amount of lytic protein released were assessed following a 4-h incubation with K562 target cells. The relative level of intracellular lytic protein was 25-50% higher, and the amount of lytic protein released was 55-65% less in atrazine-treated cells than vehicle-treated cells following incubation with the target cells. These results indicate that ATR exposure inhibits the ability of NK cells to lyse target cells by blocking lytic granule release without affecting the ability of the NK cell to form stable conjugates with target cells.« less
Characterization of Epicardial-Derived Cardiac Interstitial Cells: Differentiation and Mobilization of Heart Fibroblast Progenitors

PubMed Central

Ehrbar, Martin; Pérez-Pomares, José M.

2013-01-01

The non-muscular cells that populate the space found between cardiomyocyte fibers are known as ‘cardiac interstitial cells’ (CICs). CICs are heterogeneous in nature and include different cardiac progenitor/stem cells, cardiac fibroblasts and other cell types. Upon heart damage CICs soon respond by initiating a reparative response that transforms with time into extensive fibrosis and heart failure. Despite the biomedical relevance of CICs, controversy remains on the ontogenetic relationship existing between the different cell kinds homing at the cardiac interstitium, as well as on the molecular signals that regulate their differentiation, maturation, mutual interaction and role in adult cardiac homeostasis and disease. Our work focuses on the analysis of epicardial-derived cells, the first cell type that colonizes the cardiac interstitium. We present here a characterization and an experimental analysis of the differentiation potential and mobilization properties of a new cell line derived from mouse embryonic epicardium (EPIC). Our results indicate that these cells express some markers associated with cardiovascular stemness and retain part of the multipotent properties of embryonic epicardial derivatives, spontaneously differentiating into smooth muscle, and fibroblast/myofibroblast-like cells. Epicardium-derived cells are also shown to initiate a characteristic response to different growth factors, to display a characteristic proteolytic expression profile and to degrade biological matrices in 3D in vitro assays. Taken together, these data indicate that EPICs are relevant to the analysis of epicardial-derived CICs, and are a god model for the research on cardiac fibroblasts and the role these cells play in ventricular remodeling in both ischemic or non/ischemic myocardial disease. PMID:23349729
Development of collagen peptide-based biomaterials for tissue engineering applications

NASA Astrophysics Data System (ADS)

Hernandez Gordillo, Victor

The transition from in vitro to in vivo use of stem cells in regenerative medicine requires biomaterial scaffolds that can maintain stem cell viability and at the same time allow cell differentiation. We have previously reported the design of a collagen mimetic peptide (CMP) that assembles into a mesh-like three-dimensional (3D) structure upon the addition of metal ions and its potential for the culture of human cells. The addition of a chelating solution, such as EDTA, results in disassembly of the 3D structure, demonstrating the flexibility in the assembly/disassembly process. In the second chapter of this dissertation, we report the design of CMPs that can be functionalized with His-tagged cargoes within the 3D scaffold, via metal coordination. We show that the addition of GFP-His8 and human epidermal growth factor (hEGF-His6) has minimal effect in the assembly process. Additionally, we show that the bound hEGF-His6 can be released gradually in vitro for 5 days and induces cell proliferation in an EGF-dependent cell line. Furthermore, we functionalized the CMPs with the cell adhesion sequence (RGDS) to promote cell differentiation of two human non-tumorigenic cells lines, MCF10A and 3522-S1. In the third chapter, we evaluated the possibility of using the collagen mimetic-peptide-based (CMP) scaffolds for cell encapsulation and differentiation of human mesenchymal stem cells (hMSC). We show that hMSC encapsulated within the CMP scaffold are viable for up to 24 days post encapsulation. Moreover, hMSC at days 1, 4 and 8 days after encapsulation can be recovered from the scaffold and retain their stemness properties when analyzed for in vitro differentiation. We also demonstrate by real time PCR (RT-PCR) that genes important for osteogenic and chondrogenic differentiation are over-expressed in the absence of stimulating factors when the cells are encapsulated in the 3D scaffold at 8 and 24 days post encapsulation. Lastly, the incorporation of the cell adhesion sequence (RGDS) was shown to influence the scaffold-cell interaction. hMSCs within these RGDS-modified scaffold adopted spindle shape morphology and a complex cell organization at the outermost layer of the scaffold. In contrast, in the scaffold lacking the RGDS sequence hSMCs formed cell aggregates.
Modified multiple drug resistance phenotype of Chinese hamster ovary cells selected with X-rays and vincristine versus X-rays only.

PubMed Central

McClean, S.; Hill, B. T.

1994-01-01

Exposure of Chinese hamster ovary (CHO) cells to fractionated X-irradiation [ten fractions of 9 Gray (Gy)] resulted in the expression of a multiple drug resistance phenotype which was distinct from that of drug-selected cells in two features: (i) resistance to vinca alkaloids and epipodophyllotoxins but sensitivity to anthracyclines was retained; (ii) overexpression of P-glycoprotein (Pgp) but regulated by post-translational stability rather than by any elevation in Pgp mRNA (Hill et al., 1990). It was also reported that when these cells (designated DXR-10) were subsequently exposed to another ten fractions of 9 Gy (20 x 9 Gy in total), no further increases in drug resistance or in the extent of Pgp expression were observed. To examine this apparent plateauing of the drug resistance phenotype following X-ray pretreatment, DXR-10 cells were instead treated with ten pulsed vincristine exposures. The resultant cell line, designated DXR-10/VCR-10, proved to be more resistant to vincristine, implying that the effect of further drug selection was additive to that of X-ray pretreatment. In addition, these cells showed resistance to doxorubicin and increased Pgp expression which was matched by a concomitant elevation in Pgp mRNA. These findings appear to confirm that Pgp expression is differentially regulated in tumour cells showing drug resistance after drug as opposed to X-ray selection. Images Figure 2 Figure 3 Figure 5 PMID:7908216
Evolution of predetermined germ cells in vertebrate embryos: implications for macroevolution.

PubMed

Johnson, Andrew D; Drum, Matthew; Bachvarova, Rosemary F; Masi, Thomas; White, Mary E; Crother, Brian I

2003-01-01

The germ line is established in animal embryos with the formation of primordial germ cells (PGCs), which give rise to gametes. Therefore, the need to form PGCs can act as a developmental constraint by inhibiting the evolution of embryonic patterning mechanisms that compromise their development. Conversely, events that stabilize the PGCs may liberate these constraints. Two modes of germ cell determination exist in animal embryos: (a) either PGCs are predetermined by the inheritance of germ cell determinants (germ plasm) or (b) PGCs are formed by inducing signals secreted by embryonic tissues (i.e., regulative determination). Surprisingly, among the major extant amphibian lineages, one mechanism is found in urodeles and the other in anurans. In anuran amphibians PGCs are predetermined by germ plasm; in urodele amphibians PGCs are formed by inducing signals. To determine which mechanism is ancestral to the tetrapod lineage and to understand the pattern of inheritance in higher vertebrates, we used a phylogenetic approach to analyze basic morphological processes in both groups and correlated these with mechanisms of germ cell determination. Our results indicate that regulative germ cell determination is a property of embryos retaining ancestral embryological processes, whereas predetermined germ cells are found in embryos with derived morphological traits. These correlations suggest that regulative germ cell formation is an important developmental constraint in vertebrate embryos, acting before the highly conserved pharyngula stage. Moreover, our analysis suggests that germ plasm has evolved independently in several lineages of vertebrate embryos.
Characterization of Reversibly Immortalized Calvarial Mesenchymal Progenitor Cells.

PubMed

Shenaq, Deana S; Teven, Chad M; Seitz, Iris A; Rastegar, Farbod; Greives, Matthew R; He, Tong-Chuan; Reid, Russell R

2015-06-01

Bone morphogenetic proteins (BMPs) play a sentinel role in osteoblastic differentiation, and their implementation into clinical practice can revolutionize cranial reconstruction. Preliminary data suggest a therapeutic role of adenoviral gene delivery of BMPs in murine calvarial defect healing. Poor transgene expression inherent in direct adenoviral therapy prompted investigation of cell-based strategies. To isolate and immortalize calvarial cells as a potential progenitor source for osseous tissue engineering. Cells were isolated from murine skulls, cultured, and transduced with a retroviral vector bearing the loxP-flanked SV40 large T antigen. Immortalized calvarial cells (iCALs) were evaluated via light microscopy, immunohistochemistry, and flow cytometry to determine whether the immortalization process altered cell morphology or progenitor cell profile. Immortalized calvarial cells were then infected with adenoviral vectors encoding BMP-2 or GFP and assessed for early and late stages of osteogenic differentiation. Immortalization of calvarial cells did not alter cell morphology as demonstrated by phase contrast microscopy. Mesenchymal progenitor cell markers CD166, CD73, CD44, and CD105 were detected at varying levels in both primary cells and iCALs. Significant elevations in alkaline phosphatase activity, osteocalcin mRNA transcription, and matrix mineralization were detected in BMP-2 treated iCALs compared with GFP-treated cells. Gross and histological analyses revealed ectopic bone production from treated cells compared with controls in an in vivo stem cell implantation assay. We have established an immortalized osteoprogenitor cell line from juvenile calvarial cells that retain a progenitor cell phenotype and can successfully undergo osteogenic differentiation upon BMP-2 stimulation. These cells provide a valuable platform to investigate the molecular mechanisms underlying intramembranous bone formation and to screen for factors/small molecules that can facilitate the healing of osseous defects in the craniofacial skeleton.
Simplified Footprint-Free Cas9/CRISPR Editing of Cardiac-Associated Genes in Human Pluripotent Stem Cells.

PubMed

Kondrashov, Alexander; Duc Hoang, Minh; Smith, James G W; Bhagwan, Jamie R; Duncan, Gary; Mosqueira, Diogo; Munoz, Maria Barbadillo; Vo, Nguyen T N; Denning, Chris

2018-03-15

Modeling disease with human pluripotent stem cells (hPSCs) is hindered because the impact on cell phenotype from genetic variability between individuals can be greater than from the pathogenic mutation. While "footprint-free" Cas9/CRISPR editing solves this issue, existing approaches are inefficient or lengthy. In this study, a simplified PiggyBac strategy shortened hPSC editing by 2 weeks and required one round of clonal expansion and genotyping rather than two, with similar efficiencies to the longer conventional process. Success was shown across four cardiac-associated loci (ADRB2, GRK5, RYR2, and ACTC1) by genomic cleavage and editing efficiencies of 8%-93% and 8%-67%, respectively, including mono- and/or biallelic events. Pluripotency was retained, as was differentiation into high-purity cardiomyocytes (CMs; 88%-99%). Using the GRK5 isogenic lines as an exemplar, chronic stimulation with the β-adrenoceptor agonist, isoprenaline, reduced beat rate in hPSC-CMs expressing GRK5-Q41 but not GRK5-L41; this was reversed by the β-blocker, propranolol. This shortened, footprint-free approach will be useful for mechanistic studies.
Sperm-storage defects and live birth in Drosophila females lacking spermathecal secretory cells.

PubMed

Schnakenberg, Sandra L; Matias, Wilfredo R; Siegal, Mark L

2011-11-01

Male Drosophila flies secrete seminal-fluid proteins that mediate proper sperm storage and fertilization, and that induce changes in female behavior. Females also produce reproductive-tract secretions, yet their contributions to postmating physiology are poorly understood. Large secretory cells line the female's spermathecae, a pair of sperm-storage organs. We identified the regulatory regions controlling transcription of two genes exclusively expressed in these spermathecal secretory cells (SSC): Spermathecal endopeptidase 1 (Send1), which is expressed in both unmated and mated females, and Spermathecal endopeptidase 2 (Send2), which is induced by mating. We used these regulatory sequences to perform precise genetic ablations of the SSC at distinct time points relative to mating. We show that the SSC are required for recruiting sperm to the spermathecae, but not for retaining sperm there. The SSC also act at a distance in the reproductive tract, in that their ablation: (1) reduces sperm motility in the female's other sperm-storage organ, the seminal receptacle; and (2) causes ovoviviparity--the retention and internal development of fertilized eggs. These results establish the reproductive functions of the SSC, shed light on the evolution of live birth, and open new avenues for studying and manipulating female fertility in insects.
Reprogrammed mouse astrocytes retain a "memory" of tissue origin and possess more tendencies for neuronal differentiation than reprogrammed mouse embryonic fibroblasts.

PubMed

Tian, Changhai; Wang, Yongxiang; Sun, Lijun; Ma, Kangmu; Zheng, Jialin C

2011-02-01

Direct reprogramming of a variety of somatic cells with the transcription factors Oct4 (also called Pou5f1), Sox2 with either Klf4 and Myc or Lin28 and Nanog generates the induced pluripotent stem cells (iPSCs) with marker similarity to embryonic stem cells. However, the difference between iPSCs derived from different origins is unclear. In this study, we hypothesized that reprogrammed cells retain a "memory" of their origins and possess additional potential of related tissue differentiation. We reprogrammed primary mouse astrocytes via ectopic retroviral expression of OCT3/4, Sox2, Klf4 and Myc and found the iPSCs from mouse astrocytes expressed stem cell markers and formed teratomas in SCID mice containing derivatives of all three germ layers similar to mouse embryonic stem cells besides semblable morphologies. To test our hypothesis, we compared embryonic bodies (EBs) formation and neuronal differentiation between iPSCs from mouse embryonic fibroblasts (MEFsiPSCs) and iPSCs from mouse astrocytes (mAsiPSCs). We found that mAsiPSCs grew slower and possessed more potential for neuronal differentiation compared to MEFsiPSCs. Our results suggest that mAsiPSCs retain a "memory" of the central nervous system, which confers additional potential upon neuronal differentiation.

CD4+ T cell-mediated rejection of MHC class II-positive tumor cells is dependent on antigen secretion and indirect presentation on host APCs.

PubMed

Haabeth, Ole Audun Werner; Fauskanger, Marte; Manzke, Melanie; Lundin, Katrin U; Corthay, Alexandre; Bogen, Bjarne; Tveita, Anders Aune

2018-05-11

Tumor-specific CD4+ T cells have been shown to mediate efficient anti-tumor immune responses against cancer. Such responses can occur through direct binding to MHC class II (MHC II)-expressing tumor cells or indirectly via activation of professional antigen-presenting cells (APC) that take up and present the tumor antigen. We have previously shown that CD4+ T cells reactive against an epitope within the Ig light chain variable region of a murine B cell lymphoma can reject established tumors. Given the presence of MHC II molecules at the surface of lymphoma cells, we investigated whether MHC II-restricted antigen presentation on tumor cells alone was required for rejection. Variants of the A20 B lymphoma cell line that either secreted or intracellularly retained different versions of the tumor-specific antigen revealed that antigen secretion by the MHC II-expressing tumor cells was essential both for the priming and effector phase of CD4+ T cell-driven anti-tumor immune responses. Consistent with this, genetic ablation of MHC II in tumor cells, both in the case of B lymphoma and B16 melanoma, did not preclude rejection of tumors by tumor antigen-specific CD4+ T cells in vivo. These findings demonstrate that MHC class II expression on tumor cells themselves is not required for CD4+ T cell-mediated rejection, and that indirect display on host APC is sufficient for effective tumor elimination. These results support the importance of tumor-infiltrating APC as mediators of tumor cell killing by CD4+ T cells. Copyright ©2018, American Association for Cancer Research.
Ras-Directed N-Glycoproteins are Novel Early Biomarkers for Tumorigenesis and Malignant Transformation, and Therapeutic Targets of Neurofibromatosis Type I

DTIC Science & Technology

2012-09-01

translocation of receptors from the cytoplasm to the cell surface and retained receptors in the ER and Golgi apparatus , but had no effect on normal...glucose (2-DG) as two potential glycosylation inhibitors. Because proteins travelling to the Golgi apparatus for the consequent steps of...inhibited the transportation of receptors from the cytoplasm to the cell surface and retained receptors in the ER and Golgi apparatus (Fig 3). To
Helmet-Mounted Display Symbology and Stabilization Concepts

NASA Technical Reports Server (NTRS)

Newman, Richard L.

1995-01-01

The helmet-mounted display (HMD) presents flight, sensor, and weapon information in the pilot's line of sight. The HMD was developed to allow the pilot to retain aircraft and weapon information and to view sensor images while looking off boresight.
Perfusion-decellularized pancreas as a natural 3D scaffold for pancreatic tissue and whole organ engineering

PubMed Central

Goh, Saik-Kia; Bertera, Suzanne; Olsen, Phillip; Candiello, Joe; Halfter, Willi; Uechi, Guy; Balasubramani, Manimalha; Johnson, Scott; Sicari, Brian; Kollar, Elizabeth; Badylak, Stephen F.; Banerjee, Ipsita

2013-01-01

Approximately 285 million people worldwide suffer from diabetes, with insulin supplementation as the most common treatment measure. Regenerative medicine approaches such as a bioengineered pancreas has been proposed as potential therapeutic alternatives. A bioengineered pancreas will benefit from the development of a bioscaffold that supports and enhances cellular function and tissue development. Perfusion-decellularized organs are a likely candidate for use in such scaffolds since they mimic compositional, architectural and biomechanical nature of a native organ. In this study, we investigate perfusion-decellularization of whole pancreas and the feasibility to recellularize the whole pancreas scaffold with pancreatic cell types. Our result demonstrates that perfusion-decellularization of whole pancreas effectively removes cellular and nuclear material while retaining intricate three-dimensional microarchitecture with perfusable vasculature and ductal network and crucial extracellular matrix (ECM) components. To mimic pancreatic cell composition, we recellularized the whole pancreas scaffold with acinar and beta cell lines and cultured up to 5 days. Our result shows successful cellular engraftment within the decellularized pancreas, and the resulting graft gave rise to strong up-regulation of insulin gene expression. These findings support biological utility of whole pancreas ECM as a biomaterials scaffold for supporting and enhancing pancreatic cell functionality and represent a step toward bioengineered pancreas using regenerative medicine approaches. PMID:23787110
Aspen Tension Wood Fibers Contain β-(1→4)-Galactans and Acidic Arabinogalactans Retained by Cellulose Microfibrils in Gelatinous Walls1[OPEN

PubMed Central

Gorshkova, Tatyana; Mokshina, Natalia; Chernova, Tatyana; Ibragimova, Nadezhda; Salnikov, Vadim; Mikshina, Polina; Tryfona, Theodora; Banasiak, Alicja; Immerzeel, Peter; Dupree, Paul; Mellerowicz, Ewa J.

2015-01-01

Contractile cell walls are found in various plant organs and tissues such as tendrils, contractile roots, and tension wood. The tension-generating mechanism is not known but is thought to involve special cell wall architecture. We previously postulated that tension could result from the entrapment of certain matrix polymers within cellulose microfibrils. As reported here, this hypothesis was corroborated by sequential extraction and analysis of cell wall polymers that are retained by cellulose microfibrils in tension wood and normal wood of hybrid aspen (Populus tremula × Populus tremuloides). β-(1→4)-Galactan and type II arabinogalactan were the main large matrix polymers retained by cellulose microfibrils that were specifically found in tension wood. Xyloglucan was detected mostly in oligomeric form in the alkali-labile fraction and was enriched in tension wood. β-(1→4)-Galactan and rhamnogalacturonan I backbone epitopes were localized in the gelatinous cell wall layer. Type II arabinogalactans retained by cellulose microfibrils had a higher content of (methyl)glucuronic acid and galactose in tension wood than in normal wood. Thus, β-(1→4)-galactan and a specialized form of type II arabinogalactan are trapped by cellulose microfibrils specifically in tension wood and, thus, are the main candidate polymers for the generation of tensional stresses by the entrapment mechanism. We also found high β-galactosidase activity accompanying tension wood differentiation and propose a testable hypothesis that such activity might regulate galactan entrapment and, thus, mechanical properties of cell walls in tension wood. PMID:26378099
Aspen Tension Wood Fibers Contain β-(1---> 4)-Galactans and Acidic Arabinogalactans Retained by Cellulose Microfibrils in Gelatinous Walls.

PubMed

Gorshkova, Tatyana; Mokshina, Natalia; Chernova, Tatyana; Ibragimova, Nadezhda; Salnikov, Vadim; Mikshina, Polina; Tryfona, Theodora; Banasiak, Alicja; Immerzeel, Peter; Dupree, Paul; Mellerowicz, Ewa J

2015-11-01

Contractile cell walls are found in various plant organs and tissues such as tendrils, contractile roots, and tension wood. The tension-generating mechanism is not known but is thought to involve special cell wall architecture. We previously postulated that tension could result from the entrapment of certain matrix polymers within cellulose microfibrils. As reported here, this hypothesis was corroborated by sequential extraction and analysis of cell wall polymers that are retained by cellulose microfibrils in tension wood and normal wood of hybrid aspen (Populus tremula × Populus tremuloides). β-(1→4)-Galactan and type II arabinogalactan were the main large matrix polymers retained by cellulose microfibrils that were specifically found in tension wood. Xyloglucan was detected mostly in oligomeric form in the alkali-labile fraction and was enriched in tension wood. β-(1→4)-Galactan and rhamnogalacturonan I backbone epitopes were localized in the gelatinous cell wall layer. Type II arabinogalactans retained by cellulose microfibrils had a higher content of (methyl)glucuronic acid and galactose in tension wood than in normal wood. Thus, β-(1→4)-galactan and a specialized form of type II arabinogalactan are trapped by cellulose microfibrils specifically in tension wood and, thus, are the main candidate polymers for the generation of tensional stresses by the entrapment mechanism. We also found high β-galactosidase activity accompanying tension wood differentiation and propose a testable hypothesis that such activity might regulate galactan entrapment and, thus, mechanical properties of cell walls in tension wood. © 2015 American Society of Plant Biologists. All Rights Reserved.
Cell of Origin and Cancer Stem Cell Phenotype in Medulloblastomas

DTIC Science & Technology

2015-07-01

dominant role over some oncogene function.In addition, we recently reported that cancer stem cells (CSCs)- stem cell like cells in tumors that have stem ... cell properties and tumor initiating ability- retain epigenetic memories of their cells of origin (Chow et al., 2014). We showed that CSCs derived from
Design, Synthesis, and Properties of a Potent Inhibitor of Pseudomonas aeruginosa Deacetylase LpxC.

PubMed

Piizzi, Grazia; Parker, David T; Peng, Yunshan; Dobler, Markus; Patnaik, Anup; Wattanasin, Som; Liu, Eugene; Lenoir, Francois; Nunez, Jill; Kerrigan, John; McKenney, David; Osborne, Colin; Yu, Donghui; Lanieri, Leanne; Bojkovic, Jade; Dzink-Fox, JoAnn; Lilly, Maria-Dawn; Sprague, Elizabeth R; Lu, Yipin; Wang, Hongming; Ranjitkar, Srijan; Xie, Lili; Wang, Bing; Glick, Meir; Hamann, Lawrence G; Tommasi, Ruben; Yang, Xia; Dean, Charles R

2017-06-22

Over the past several decades, the frequency of antibacterial resistance in hospitals, including multidrug resistance (MDR) and its association with serious infectious diseases, has increased at alarming rates. Pseudomonas aeruginosa is a leading cause of nosocomial infections, and resistance to virtually all approved antibacterial agents is emerging in this pathogen. To address the need for new agents to treat MDR P. aeruginosa, we focused on inhibiting the first committed step in the biosynthesis of lipid A, the deacetylation of uridyldiphospho-3-O-(R-hydroxydecanoyl)-N-acetylglucosamine by the enzyme LpxC. We approached this through the design, synthesis, and biological evaluation of novel hydroxamic acid LpxC inhibitors, exemplified by 1, where cytotoxicity against mammalian cell lines was reduced, solubility and plasma-protein binding were improved while retaining potent anti-pseudomonal activity in vitro and in vivo.
Maintenance of Taste Organs Is Strictly Dependent on Epithelial Hedgehog/GLI Signaling.

PubMed

Ermilov, Alexandre N; Kumari, Archana; Li, Libo; Joiner, Ariell M; Grachtchouk, Marina A; Allen, Benjamin L; Dlugosz, Andrzej A; Mistretta, Charlotte M

2016-11-01

For homeostasis, lingual taste papilla organs require regulation of epithelial cell survival and renewal, with sustained innervation and stromal interactions. To investigate a role for Hedgehog/GLI signaling in adult taste organs we used a panel of conditional mouse models to manipulate GLI activity within epithelial cells of the fungiform and circumvallate papillae. Hedgehog signaling suppression rapidly led to taste bud loss, papilla disruption, and decreased proliferation in domains of papilla epithelium that contribute to taste cells. Hedgehog responding cells were eliminated from the epithelium but retained in the papilla stromal core. Despite papilla disruption and loss of taste buds that are a major source of Hedgehog ligand, innervation to taste papillae was maintained, and not misdirected, even after prolonged GLI blockade. Further, vimentin-positive fibroblasts remained in the papilla core. However, retained innervation and stromal cells were not sufficient to maintain taste bud cells in the context of compromised epithelial Hedgehog signaling. Importantly taste organ disruption after GLI blockade was reversible in papillae that retained some taste bud cell remnants where reactivation of Hedgehog signaling led to regeneration of papilla epithelium and taste buds. Therefore, taste bud progenitors were either retained during epithelial GLI blockade or readily repopulated during recovery, and were poised to regenerate taste buds once Hedgehog signaling was restored, with innervation and papilla connective tissue elements in place. Our data argue that Hedgehog signaling is essential for adult tongue tissue maintenance and that taste papilla epithelial cells represent the key targets for physiologic Hedgehog-dependent regulation of taste organ homeostasis. Because disruption of GLI transcriptional activity in taste papilla epithelium is sufficient to drive taste organ loss, similar to pharmacologic Hedgehog pathway inhibition, the findings suggest that taste alterations in cancer patients using systemic Hedgehog pathway inhibitors result principally from interruption of signaling activity in taste papillae.
Maintenance of Taste Organs Is Strictly Dependent on Epithelial Hedgehog/GLI Signaling

PubMed Central

Mistretta, Charlotte M.

2016-01-01

For homeostasis, lingual taste papilla organs require regulation of epithelial cell survival and renewal, with sustained innervation and stromal interactions. To investigate a role for Hedgehog/GLI signaling in adult taste organs we used a panel of conditional mouse models to manipulate GLI activity within epithelial cells of the fungiform and circumvallate papillae. Hedgehog signaling suppression rapidly led to taste bud loss, papilla disruption, and decreased proliferation in domains of papilla epithelium that contribute to taste cells. Hedgehog responding cells were eliminated from the epithelium but retained in the papilla stromal core. Despite papilla disruption and loss of taste buds that are a major source of Hedgehog ligand, innervation to taste papillae was maintained, and not misdirected, even after prolonged GLI blockade. Further, vimentin-positive fibroblasts remained in the papilla core. However, retained innervation and stromal cells were not sufficient to maintain taste bud cells in the context of compromised epithelial Hedgehog signaling. Importantly taste organ disruption after GLI blockade was reversible in papillae that retained some taste bud cell remnants where reactivation of Hedgehog signaling led to regeneration of papilla epithelium and taste buds. Therefore, taste bud progenitors were either retained during epithelial GLI blockade or readily repopulated during recovery, and were poised to regenerate taste buds once Hedgehog signaling was restored, with innervation and papilla connective tissue elements in place. Our data argue that Hedgehog signaling is essential for adult tongue tissue maintenance and that taste papilla epithelial cells represent the key targets for physiologic Hedgehog-dependent regulation of taste organ homeostasis. Because disruption of GLI transcriptional activity in taste papilla epithelium is sufficient to drive taste organ loss, similar to pharmacologic Hedgehog pathway inhibition, the findings suggest that taste alterations in cancer patients using systemic Hedgehog pathway inhibitors result principally from interruption of signaling activity in taste papillae. PMID:27893742
Primary clear cell renal carcinoma cells display minimal mitochondrial respiratory capacity resulting in pronounced sensitivity to glycolytic inhibition by 3-Bromopyruvate

PubMed Central

Nilsson, H; Lindgren, D; Mandahl Forsberg, A; Mulder, H; Axelson, H; Johansson, M E

2015-01-01

Changes of cellular metabolism are an integral property of the malignant potential of most cancer cells. Already in the 1930s, Otto Warburg observed that tumor cells preferably utilize glycolysis and lactate fermentation for energy production, rather than the mitochondrial oxidative phosphorylation dominating in normal cells, a phenomenon today known as the Warburg effect. Even though many tumor types display a high degree of aerobic glycolysis, they still retain the activity of other energy-producing metabolic pathways. One exception seems to be the clear cell variant of renal cell carcinoma, ccRCC, where the activity of most other pathways than that of glycolysis has been shown to be reduced. This makes ccRCC a promising candidate for the use of glycolytic inhibitors in treatment of the disease. However, few studies have so far addressed this issue. In this report, we show a strikingly reduced mitochondrial respiratory capacity of primary human ccRCC cells, resulting in enhanced sensitivity to glycolytic inhibition by 3-Bromopyruvate (3BrPA). This effect was largely absent in established ccRCC cell lines, a finding that highlights the importance of using biologically relevant models in the search for new candidate cancer therapies. 3BrPA markedly reduced ATP production in primary ccRCC cells, followed by cell death. Our data suggest that glycolytic inhibitors such as 3BrPA, that has been shown to be well tolerated in vivo, should be further analyzed for the possible development of selective treatment strategies for patients with ccRCC. PMID:25569102
Primary clear cell renal carcinoma cells display minimal mitochondrial respiratory capacity resulting in pronounced sensitivity to glycolytic inhibition by 3-Bromopyruvate.

PubMed

Nilsson, H; Lindgren, D; Mandahl Forsberg, A; Mulder, H; Axelson, H; Johansson, M E

2015-01-08

Changes of cellular metabolism are an integral property of the malignant potential of most cancer cells. Already in the 1930s, Otto Warburg observed that tumor cells preferably utilize glycolysis and lactate fermentation for energy production, rather than the mitochondrial oxidative phosphorylation dominating in normal cells, a phenomenon today known as the Warburg effect. Even though many tumor types display a high degree of aerobic glycolysis, they still retain the activity of other energy-producing metabolic pathways. One exception seems to be the clear cell variant of renal cell carcinoma, ccRCC, where the activity of most other pathways than that of glycolysis has been shown to be reduced. This makes ccRCC a promising candidate for the use of glycolytic inhibitors in treatment of the disease. However, few studies have so far addressed this issue. In this report, we show a strikingly reduced mitochondrial respiratory capacity of primary human ccRCC cells, resulting in enhanced sensitivity to glycolytic inhibition by 3-Bromopyruvate (3BrPA). This effect was largely absent in established ccRCC cell lines, a finding that highlights the importance of using biologically relevant models in the search for new candidate cancer therapies. 3BrPA markedly reduced ATP production in primary ccRCC cells, followed by cell death. Our data suggest that glycolytic inhibitors such as 3BrPA, that has been shown to be well tolerated in vivo, should be further analyzed for the possible development of selective treatment strategies for patients with ccRCC.
Neuromast hair cells retain the capacity of regeneration during heavy metal exposure.

PubMed

Montalbano, G; Capillo, G; Laurà, R; Abbate, F; Levanti, M; Guerrera, M C; Ciriaco, E; Germanà, A

2018-07-01

The neuromast is the morphological unit of the lateral line of fishes and is composed of a cluster of central sensory cells (hair cells) surrounded by support and mantle cells. Heavy metals exposure leads to disruption of hair cells within the neuromast. It is well known that the zebrafish has the ability to regenerate the hair cells after damage caused by toxicants. The process of regeneration depends on proliferation, differentiation and cellular migration of sensory and non-sensory progenitor cells. Therefore, our study was made in order to identify which cellular types are involved in the complex process of regeneration during heavy metals exposure. For this purpose, adult zebrafish were exposed to various heavy metals (Arsenic, cadmium and zinc) for 72h. After acute (24h) exposure, immunohistochemical localization of S100 (a specific marker for hair cells) in the neuromasts highlighted the hair cells loss. The immunoreaction for Sox2 (a specific marker for stem cells), at the same time, was observed in the support and mantle cells, after exposure to arsenic and cadmium, while only in the support cells after exposure to zinc. After chronic (72h) exposure the hair cells were regenerated, showing an immunoreaction for S100 protein. At the same exposure time to the three metals, a Sox2 immunoreaction was expressed in support and mantle cells. Our results showed for the first time the regenerative capacity of hair cells, not only after, but also during exposure to heavy metals, demonstrated by the presence of different stem cells that can diversify in hair cells. Copyright © 2018 Elsevier GmbH. All rights reserved.
Ex vivo preservation and expansion of human limbal epithelial stem cells on amniotic membrane cultures.

PubMed

Meller, D; Pires, R T F; Tseng, S C G

2002-04-01

Amniotic membrane (AM) transplantation effectively expands the remaining limbal epithelial stem cells in patients with partial limbal stem cell deficiency. The authors investigated whether this action could be produced ex vivo. The outgrowth rate on AM was compared among explants derived from human limbus, peripheral cornea, and central cornea. For outgrowth of human limbal epithelial cells (HLEC), cell cycle kinetics were measured by BrdU labelling for 1 or 7 days, of which the latter was also chased in primary cultures, secondary 3T3 fibroblast cultures, and in athymic Balb/c mice following a brief treatment with a phorbol ester. Epithelial morphology was studied by histology and transmission electron microscopy, and phenotype was defined by immunostaining with monoclonal antibodies to keratins and mucins. Outgrowth rate was 0/22 (0%) and 2/24 (8.3%) for central and peripheral corneal explants, respectively, but was 77/80 (96.2%) for limbal explants (p <0.0001). 24 hour BrdU labelling showed a uniformly low (that is, less than 5%) labelling index in 65% of the limbal explants, but a mixed pattern with areas showing a high (that is, more than 40%) labelling index in 35% of limbal explants, and in all (100%) peripheral corneal explants. Continuous BrdU labelling for 7 days detected a high labelling index in 61.5% of the limbal explants with the remainder still retaining a low labelling index. A number of label retaining cells were noted after 7 day labelling followed by 14 days of chase in primary culture or by 21 days of chase after transplantation to 3T3 fibroblast feeder layers. After exposure to phorbol 12-myristate 13-acetate for 24 hours and 7 day labelling, HLEC transplanted in athymic mice still showed a number of label retaining basal cells after 9 days of chase. HLEC cultured on AM were strongly positive for K14 keratin and MUC4 and slightly positive in suprabasal cells for K3 keratin but negative for K12 keratin, AMEM2, and MUC5AC. After subcutaneous implantation in athymic mice, the resultant epithelium was markedly stratified and the basal epithelial cells were strongly positive for K14 keratin, while the suprabasal epithelial cells were strongly positive for K3 keratin and MUC4, and the entire epithelium was negative for K12 keratin and MUC5A/C. These data support the notion that AM cultures preferentially preserve and expand limbal epithelial stem cells that retain their in vivo properties of slow cycling, label retaining, and undifferentiation. This finding supports the feasibility of ex vivo expansion of limbal epithelial stem cells for treating patients with total limbal stem cell deficiency using a small amount of donor limbal tissue.
Treatment of Stage IV Non-small Cell Lung Cancer

PubMed Central

Evans, Tracey; Gettinger, Scott; Hensing, Thomas A.; VanDam Sequist, Lecia; Ireland, Belinda; Stinchcombe, Thomas E.

2013-01-01

Background: Stage IV non-small cell lung cancer (NSCLC) is a treatable, but not curable, clinical entity in patients given the diagnosis at a time when their performance status (PS) remains good. Methods: A systematic literature review was performed to update the previous edition of the American College of Chest Physicians Lung Cancer Guidelines. Results: The use of pemetrexed should be restricted to patients with nonsquamous histology. Similarly, bevacizumab in combination with chemotherapy (and as continuation maintenance) should be restricted to patients with nonsquamous histology and an Eastern Cooperative Oncology Group (ECOG) PS of 0 to 1; however, the data now suggest it is safe to use in those patients with treated and controlled brain metastases. Data at this time are insufficient regarding the safety of bevacizumab in patients receiving therapeutic anticoagulation who have an ECOG PS of 2. The role of cetuximab added to chemotherapy remains uncertain and its routine use cannot be recommended. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors as first-line therapy are the recommended treatment of those patients identified as having an EGFR mutation. The use of maintenance therapy with either pemetrexed or erlotinib should be considered after four cycles of first-line therapy in those patients without evidence of disease progression. The use of second- and third-line therapy in stage IV NSCLC is recommended in those patients retaining a good PS; however, the benefit of therapy beyond the third-line setting has not been demonstrated. In the elderly and in patients with a poor PS, the use of two-drug, platinum-based regimens is preferred. Palliative care should be initiated early in the course of therapy for stage IV NSCLC. Conclusions: Significant advances continue to be made, and the treatment of stage IV NSCLC has become nuanced and specific for particular histologic subtypes and clinical patient characteristics and according to the presence of specific genetic mutations. PMID:23649446
p75 neurotrophin receptor is involved in proliferation of undifferentiated mouse embryonic stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moscatelli, Ilana; Pierantozzi, Enrico; Camaioni, Antonella

2009-11-01

Neurotrophins and their receptors are known to play a role in the proliferation and survival of many different cell types of neuronal and non-neuronal lineages. In addition, there is much evidence in the literature showing that the p75 neurotrophin receptor (p75{sup NTR}), alone or in association with members of the family of Trk receptors, is expressed in a wide variety of stem cells, although its role in such cells has not been completely elucidated. In the present work we have investigated the expression of p75{sup NTR} and Trks in totipotent and pluripotent cells, the mouse pre-implantation embryo and embryonic stemmore » and germ cells (ES and EG cells). p75{sup NTR} and TrkA can be first detected in the blastocyst from which ES cell lines are derived. Mouse ES cells retain p75{sup NTR}/TrkA expression. Nerve growth factor is the only neurotrophin able to stimulate ES cell growth in culture, without affecting the expression of stem cell markers, alkaline phosphatase, Oct4 and Nanog. Such proliferation effect was blocked by antagonizing either p75{sup NTR} or TrkA. Interestingly, immunoreactivity to anti-p75{sup NTR} antibodies is lost upon ES cell differentiation. The expression pattern of neurotrophin receptors in murine ES cells differs from human ES cells, that only express TrkB and C, and do not respond to NGF. In this paper we also show that, while primordial germ cells (PGC) do not express p75{sup NTR}, when they are made to revert to an ES-like phenotype, becoming EG cells, expression of p75{sup NTR} is turned on.« less
Method of lining a vertical mine shaft with concrete

DOEpatents

Eklund, James D.; Halter, Joseph M.; Rasmussen, Donald E.; Sullivan, Robert G.; Moffat, Robert B.

1981-01-01

The apparatus includes a cylindrical retainer form spaced inwardly of the wall of the shaft by the desired thickness of the liner to be poured and having overlapping edges which seal against concrete flow but permit the form to be contracted to a smaller circumference after the liner has hardened and is self-supporting. A curb ring extends downwardly and outwardly toward the shaft wall from the bottom of the retainer form to define the bottom surface of each poured liner section. An inflatable toroid forms a seal between the curb ring and the shaft wall. A form support gripper ring having gripper shoes laterally extendable under hydraulic power to engage the shaft wall supports the retainer form, curb ring and liner until the newly poured liner section becomes self-supporting. Adjusting hydraulic cylinders permit the curb ring and retainer form to be properly aligned relative to the form support gripper ring. After a liner section is self-supporting, an advancing system advances the retainer form, curb ring and form support gripper ring toward a shaft boring machine above which the liner is being formed. The advancing system also provides correct horizontal alignment of the form support gripper ring.
Ion transport by primary cultures of canine tracheal epithelium: methodology, morphology, and electrophysiology.

PubMed

Welsh, M J

1985-01-01

Canine tracheal epithelial cells were isolated by enzymatic and mechanical dispersion and cultured on permeable supports. The cells formed confluent monolayers and retained most of the morphologic characteristics of the intact epithelium, including apical microvilli, apical tight junctions, and a moderately interdigitated lateral intercellular space. The cells also retained the functional properties of the epithelium. The monolayer responded to addition of isoproterenol with the characteristic changes in cellular electrical properties expected for stimulation of C1 secretion: isoproterenol increased transepithelial voltage, depolarized apical membrane voltage, and decreased both transepithelial resistance and the ratio of apical-to-basolateral membrane resistance. Examination of the cellular response to ion substitutions and inhibitors of C1 secretion indicate that the cultured monolayers retain the same cellular mechanisms of ion transport as the intact epithelium. Thus, primary cultures of tracheal epithelium may provide a useful preparation for future studies of the mechanism and regulation of C1 secretion by airway epithelia.
Atomic Scale Understanding of Poly-Si/SiO2/c-Si Passivated Contacts: Passivation Degradation Due to Metallization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aguiar, Jeffery A.; Young, David; Lee, Benjamin

2016-11-21

The key attributes for achieving high efficiency crystalline silicon solar cells include class leading developments in the ability to approach the theoretical limits of silicon solar technology (29.4% efficiency). The push for high efficiency devices is further compounded with the clear need for passivation to reduce recombination at the metal contacts. At the same time there is stringent requirement to retain the same material device quality, surface passivation, and performance characteristics following subsequent processing. The development of passivated silicon cell structures that retain active front and rear surface passivation and overall material cell quality is therefore a relevant and activemore » area of development. To address the potential outcomes of metallization on passivated silicon stack, we report on some common microstructural features of degradation due to metallization for a series of silicon device stacks. A fundamental materials understanding of the metallization process on retaining high-efficiency passivated Si devices is therefore gained over these series of results.« less
Acquired EGFR L718V mutation mediates resistance to osimertinib in non-small cell lung cancer but retains sensitivity to afatinib.

PubMed

Liu, Yutao; Li, Yan; Ou, Qiuxiang; Wu, Xue; Wang, Xiaonan; Shao, Yang W; Ying, Jianming

2018-04-01

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are promising targeted therapies for EGFR-mutated non-small-cell lung cancer (NSCLC) patients. However, acquired resistance inevitably develops. Comprehensive and dynamic companion genomic diagnosis can gain insights into underlying resistance mechanisms, thereby help oncologists and patients to make informed decision on the potential benefit of the treatment. A 67-year-old male who was initially diagnosed of EGFR L858R-mediated NSCLC received multiple lines of chemotherapy and EGFR TKI therapies after surgery. The EGFR mutational status of individual metastatic lesion was determined by genetic testing of the tumor tissue biopsies using next generation sequencing (NGS) throughout the patient's clinical course. An acquired potentially drug-resistant EGFR mutation was functionally validated in vitro and its sensitivity to different EGFR TKIs was assessed simultaneously. We have identified distinct resistance mechanisms to EGFR blockade in different metastatic lung lesions. Acquired EGFR T790M was first detected that leads to the resistance to the gefitinib treatment. Consequently, osimertinib was administrated and the response lasted until disease progressed. We identified a newly acquired EGFR L718V mutation in one lesion in conjunction with L858R, but not T790M, which showed stable disease on the following erlotinib treatment, while EGFR C797S together with L858R/T790M was detected in the other lesion that continuously progressed. In vitro functional studies demonstrated that EGFR-L858R/L718V confers resistance to osimertinib, but retains sensitivity to the second generation TKI afatinib. We reported that distinct resistance mechanisms could arise in different metastases within the same patient in response to EGFR blockade. We also demonstrated in vitro that EGFR L718V mutation mediates resistance to osimertinib, but retains sensitivity to afatinib. We evidenced that dynamic companion genomic diagnosis offers valuable information to help define the mechanisms of drug resistance and to guide the selection of subsequent treatment. Copyright © 2018 Elsevier B.V. All rights reserved.

A novel nitro-oxy substituted analogue of rofecoxib reduces human colon cancer cell growth.

PubMed

Bocca, Claudia; Bozzo, Francesca; Ievolella, Monica; Miglietta, Antonella

2012-02-01

Rofecoxib is a specific COX-2 inhibitor able to exert antiproliferative activity against colorectal cancer cells. It was withdrawn from the market after the demonstration of an increased risk of cardiovascular complications after prolonged use. Nevertheless, it remains an interesting compound for laboratory research as an experimental COX-2 inhibitor. In this study, the antiproliferative activity of a novel dinitro-oxy-substituted analogue of rofecoxib (NO-rofe), potentially less cardiotoxic, has been investigated in vitro on human colon cancer cells and compared with the action of the parent drug. Due to the fact that COX-2 inhibition is the main characteristic of coxibs, we performed all experiments in COX-2-overexpressing (HT-29) and COX-2-negative (SW-480) human colon cancer cells, to elucidate whether the observed effects were dependent on COX-2 inhibition. Moreover, experiments were performed in order to evaluate whether COX-2 pharmacological inhibition may affect beta-catenin/E-cadherin signaling pathway. NO-rofe exerted a significant antiproliferative activity on COX-2 positive HT-29 human colon cancer cells, being less effective on the COX-2 negative SW-480 human colon cancer cell line. In particular, the rofecoxib analogue retained similar potencies with respect to COX-2 inhibition but was much more active than rofecoxib in inhibiting the growth of human colon cancer cells in vitro. In addition, this novel compound resulted in the induction of membrane β-catenin/E-cadherin expression, a feature that may significantly contribute to its antiproliferative activity.
ERK1/2 signaling mediated naringin-induced osteogenic differentiation of immortalized human periodontal ligament stem cells.

PubMed

Wei, Kai; Xie, Yuansheng; Chen, Tianyu; Fu, Bo; Cui, Shaoyuan; Wang, Yan; Cai, Guangyan; Chen, Xiangmei

2017-07-29

Periodontal ligament stem cells (PDLSCs) are promising tools for the investigations of cell differentiation and bone regeneration. However, the limited life span significantly restricts their usefulness. In this study, we established an immortalized PDLSC cell line by the introduction of Bmi1 (PDLSC-Bmi1). Several genes related to cell cycle, cell replication and stemness were found to be changed with the overexpression of Bmi1. Compared with primary PDLSCs, the immortalized cells had a slower aging rate, maintained in a proliferative state without crisis for more than 30 passages, and retained the molecular markers and biological functions of primary ones. Using the PDLSC-Bmi1, we confirmed the promotive effect of naringin on osteogenesis. Naringin promoted the osteogenic differentiation of PDLSC-Bmi1 manifested as the increased activity of alkaline phosphatase (ALP), expression of the runt-related transcription factor 2 (Runx2) and osteocalcin (OCN), and formation of mineralized nodules. In addition, the extracellular regulated protein kinases (ERK) 1/2 was found to be activated by naringin, and the ERK1/2 specific inhibitor significantly inhibited naringin-induced osteogenic differentiation in PDLSC-Bmi1. Our results indicated that the overexpression of Bmi1 extended the life span of PDLSCs without perturbing their biological functions, and that naringin promoted the osteogenesis of PDLSC-Bmi1 at least partially through the ERK1/2 signaling pathway. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.
Circadian Timing in the Lung; A Specific Role for Bronchiolar Epithelial Cells

PubMed Central

Gibbs, J. E.; Beesley, S.; Plumb, J.; Singh, D.; Farrow, S.; Ray, D. W.; Loudon, A. S. I.

2015-01-01

In addition to the core circadian oscillator, located within the suprachiasmatic nucleus, numerous peripheral tissues possess self-sustaining circadian timers. In vivo these are entrained and temporally synchronized by signals conveyed from the core oscillator. In the present study, we examine circadian timing in the lung, determine the cellular localization of core clock proteins in both mouse and human lung tissue, and establish the effects of glucocorticoids (widely used in the treatment of asthma) on the pulmonary clock. Using organotypic lung slices prepared from transgenic mPER2::Luc mice, luciferase levels, which report PER2 expression, were measured over a number of days. We demonstrate a robust circadian rhythm in the mouse lung that is responsive to glucocorticoids. Immunohistochemical techniques were used to localize specific expression of core clock proteins, and the glucocorticoid receptor, to the epithelial cells lining the bronchioles in both mouse and human lung. In the mouse, these were established to be Clara cells. Murine Clara cells retained circadian rhythmicity when grown as a pure population in culture. Furthermore, selective ablation of Clara cells resulted in the loss of circadian rhythm in lung slices, demonstrating the importance of this cell type in maintaining overall pulmonary circadian rhythmicity. In summary, we demonstrate that Clara cells are critical for maintaining coherent circadian oscillations in lung tissue. Their coexpression of the glucocorticoid receptor and core clock components establishes them as a likely interface between humoral suprachiasmatic nucleus output and circadian lung physiology. PMID:18787022
Human Induced Pluripotent Stem Cell-Derived Podocytes Mature into Vascularized Glomeruli upon Experimental Transplantation.

PubMed

Sharmin, Sazia; Taguchi, Atsuhiro; Kaku, Yusuke; Yoshimura, Yasuhiro; Ohmori, Tomoko; Sakuma, Tetsushi; Mukoyama, Masashi; Yamamoto, Takashi; Kurihara, Hidetake; Nishinakamura, Ryuichi

2016-06-01

Glomerular podocytes express proteins, such as nephrin, that constitute the slit diaphragm, thereby contributing to the filtration process in the kidney. Glomerular development has been analyzed mainly in mice, whereas analysis of human kidney development has been minimal because of limited access to embryonic kidneys. We previously reported the induction of three-dimensional primordial glomeruli from human induced pluripotent stem (iPS) cells. Here, using transcription activator-like effector nuclease-mediated homologous recombination, we generated human iPS cell lines that express green fluorescent protein (GFP) in the NPHS1 locus, which encodes nephrin, and we show that GFP expression facilitated accurate visualization of nephrin-positive podocyte formation in vitro These induced human podocytes exhibited apicobasal polarity, with nephrin proteins accumulated close to the basal domain, and possessed primary processes that were connected with slit diaphragm-like structures. Microarray analysis of sorted iPS cell-derived podocytes identified well conserved marker gene expression previously shown in mouse and human podocytes in vivo Furthermore, we developed a novel transplantation method using spacers that release the tension of host kidney capsules, thereby allowing the effective formation of glomeruli from human iPS cell-derived nephron progenitors. The human glomeruli were vascularized with the host mouse endothelial cells, and iPS cell-derived podocytes with numerous cell processes accumulated around the fenestrated endothelial cells. Therefore, the podocytes generated from iPS cells retain the podocyte-specific molecular and structural features, which will be useful for dissecting human glomerular development and diseases. Copyright © 2016 by the American Society of Nephrology.
The age-dependent epigenetic and physiological changes in an Arabidopsis T87 cell suspension culture during long-term cultivation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwiatkowska, Aleksandra, E-mail: A.Kwiatkows@gmail.com; Zebrowski, Jacek; Oklejewicz, Bernadetta

2014-05-02

Highlights: • A decrease in proliferation rate during long-term cultivation of Arabidopsis cells. • Age-dependent increase in senescence-associated gene expression in Arabidopsis cells. • Age-related increase in DNA methylation, H3K9me2, and H3K27me3 in Arabidopsis cells. • High potential of photosynthetic efficiency of long-term cultured Arabidopsis cells. - Abstract: Plant cell suspension cultures represent good model systems applicable for both basic research and biotechnological purposes. Nevertheless, it is widely known that a prolonged in vitro cultivation of plant cells is associated with genetic and epigenetic instabilities, which may limit the usefulness of plant lines. In this study, the age-dependent epigenetic andmore » physiological changes in an asynchronous Arabidopsis T87 cell culture were examined. A prolonged cultivation period was found to be correlated with a decrease in the proliferation rate and a simultaneous increase in the expression of senescence-associated genes, indicating that the aging process started at the late growth phase of the culture. In addition, increases in the heterochromatin-specific epigenetic markers, i.e., global DNA methylation, H3K9 dimethylation, and H3K27 trimethylation, were observed, suggesting the onset of chromatin condensation, a hallmark of the early stages of plant senescence. Although the number of live cells decreased with an increase in the age of the culture, the remaining viable cells retained a high potential to efficiently perform photosynthesis and did not exhibit any symptoms of photosystem II damage.« less
Los Alamos National Laboratory JOWOG 31 Weapons Engineering Education & Training

DOE Office of Scientific and Technical Information (OSTI.GOV)

Domzalski, Mark W.

The objectives of this report are to recruit talented staff, invest in new and early/mid career staff, retain trained and talented staff and future leaders, and shorten the ~5-10 year time line to realize new Weaponeers.
Synthesis of curcumin-functionalized gold nanoparticles and cytotoxicity studies in human prostate cancer cell line

NASA Astrophysics Data System (ADS)

Nambiar, Shruti; Osei, Ernest; Fleck, Andre; Darko, Johnson; Mutsaers, Anthony J.; Wettig, Shawn

2018-03-01

Gold nanoparticles synthesized using plant extracts with medicinal properties have gained traction in recent years, especially for their use in various biomedical applications. Colloidal stability of these nanoparticles in different environments is critical to retain the expected therapeutic/diagnostic efficacy and toxicological outcome. Any change in the colloidal stability leads to dramatic changes in the physico-chemical properties of the nanoparticles such as size and surface charge, which in turn may alter the biological activity of the particles. Such changes are imminent in physiologically-relevant environment wherein interactions with different biomolecules, such as serum proteins, may modify the overall properties of the nanoparticles. In this regard, we synthesized 15 nm sized gold nanoparticles using curcumin, a plant extract from turmeric root, to evaluate cytotoxicity, uptake, and localization in human prostate cancer cells using cell-culture medium supplemented with or without fetal bovine serum (FBS). The results indicate a dramatic difference in the cytotoxicity and uptake between cells treated with curcumin-functionalized gold nanoparticles (cur-AuNPs) in cell-culture medium with and without serum. The addition of FBS to the medium not only increased the stability of the nanoparticles but also enhanced the biocompatibility (i.e. minimal cytotoxicity for a wide range of cur-AuNP concentrations). We conclude that the presence of serum proteins significantly impact the therapeutic potential of cur-AuNPs.
DLEU2, frequently deleted in malignancy, functions as a critical host gene of the cell cycle inhibitory microRNAs miR-15a and miR-16-1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lerner, Mikael; Harada, Masako; Loven, Jakob

The microRNAs miR-15a and miR-16-1 are downregulated in multiple tumor types and are frequently deleted in chronic lymphocytic leukemia (CLL), myeloma and mantle cell lymphoma. Despite their abundance in most cells the transcriptional regulation of miR-15a/16-1 remains unclear. Here we demonstrate that the putative tumor suppressor DLEU2 acts as a host gene of these microRNAs. Mature miR-15a/miR-16-1 are produced in a Drosha-dependent process from DLEU2 and binding of the Myc oncoprotein to two alterative DLEU2 promoters represses both the host gene transcript and levels of mature miR-15a/miR-16-1. In line with a functional role for DLEU2 in the expression of themore » microRNAs, the miR-15a/miR-16-1 locus is retained in four CLL cases that delete both promoters of this gene and expression analysis indicates that this leads to functional loss of mature miR-15a/16-1. We additionally show that DLEU2 negatively regulates the G1 Cyclins E1 and D1 through miR-15a/miR-16-1 and provide evidence that these oncoproteins are subject to miR-15a/miR-16-1-mediated repression under normal conditions. We also demonstrate that DLEU2 overexpression blocks cellular proliferation and inhibits the colony-forming ability of tumor cell lines in a miR-15a/miR-16-1-dependent way. Together the data illuminate how inactivation of DLEU2 promotes cell proliferation and tumor progression through functional loss of miR-15a/miR-16-1.« less
Visual Agnosia for Line Drawings and Silhouettes without Apparent Impairment of Real-Object Recognition: A Case Report

PubMed Central

Hiraoka, Kotaro; Suzuki, Kyoko; Hirayama, Kazumi; Mori, Etsuro

2009-01-01

We report on a patient with visual agnosia for line drawings and silhouette pictures following cerebral infarction in the region of the right posterior cerebral artery. The patient retained the ability to recognize real objects and their photographs, and could precisely copy line drawings of objects that she could not name. This case report highlights the importance of clinicians and researchers paying special attention to avoid overlooking agnosia in such cases. The factors that lead to problems in the identification of stimuli other than real objects in agnosic cases are discussed. PMID:19996516
Visual agnosia for line drawings and silhouettes without apparent impairment of real-object recognition: a case report.

PubMed

Hiraoka, Kotaro; Suzuki, Kyoko; Hirayama, Kazumi; Mori, Etsuro

2009-01-01

We report on a patient with visual agnosia for line drawings and silhouette pictures following cerebral infarction in the region of the right posterior cerebral artery. The patient retained the ability to recognize real objects and their photographs, and could precisely copy line drawings of objects that she could not name. This case report highlights the importance of clinicians and researchers paying special attention to avoid overlooking agnosia in such cases. The factors that lead to problems in the identification of stimuli other than real objects in agnosic cases are discussed.
Ex Vivo Expanded Natural Killer Cells Demonstrate Robust Proliferation In Vivo In High-Risk Relapsed Multiple Myeloma Patients

PubMed Central

Szmania, Susann; Lapteva, Natalia; Garg, Tarun; Greenway, Amy; Lingo, Joshuah; Nair, Bijay; Stone, Katie; Woods, Emily; Khan, Junaid; Stivers, Justin; Panozzo, Susan; Campana, Dario; Bellamy, William T.; Robbins, Molly; Epstein, Joshua; Yaccoby, Shmuel; Waheed, Sarah; Gee, Adrian; Cottler-Fox, Michele; Rooney, Cliona; Barlogie, Bart; van Rhee, Frits

2015-01-01

Highly activated/expanded natural killer (NK) cells can be generated via stimulation with the HLA-deficient cell line K562 genetically modified to express 41BB-ligand and membrane-bound interleukin (IL)15. We tested the safety, persistence and activity of expanded NK cells generated from myeloma patients (auto-NK) or haplo-identical family donors (allo-NK) in heavily pretreated patients with high-risk relapsing myeloma. The preparative regimen comprised bortezomib only or bortezomib and immunosuppression with cyclophosphamide, dexamethasone and fludarabine. NK cells were shipped overnight either cryopreserved or fresh. In 8 patients, up to 1×108 NK cells/kg were infused on day 0 and followed by daily administrations of IL2. Significant in vivo expansion was observed only in the 5 patients receiving fresh products, peaking at or near day 7, with the highest NK cell counts in 2 subjects who received cells produced in a high concentration of IL2 (500 units/mL). Seven days after infusion, donor NK cells comprised > 90% of circulating leukocytes in fresh allo-NK cell recipients, and cytolytic activity against allogeneic myeloma targets was retained in vitro. Among the 7 evaluable patients, there were no serious adverse events that could be related to NK cell infusion. One patient had a partial response and in another the tempo of disease progression decreased; neither patient required further therapy for 6 months. In the 5 remaining patients, disease progression was not affected by NK cell infusion. In conclusion, infusion of large numbers of expanded NK cells was feasible and safe; infusing fresh cells was critical to their expansion in vivo. PMID:25415285
Reciprocal relationship between alpha1,2 mannosidase processing and reglucosylation in the rough endoplasmic reticulum of Man-P-Dol deficient cells.

PubMed

Duvet, S; Chirat, F; Mir, A M; Verbert, A; Dubuisson, J; Cacan, R

2000-02-01

The study of the glycosylation pathway of a mannosylphosphoryldolichol-deficient CHO mutant cell line (B3F7) reveals that truncated Glc(0-3)Man5GlcNAc2 oligosaccharides are transferred onto nascent proteins. Pulse-chase experiments indicate that these newly synthesized glycoproteins are retained in intracellular compartments and converted to Man4GlcNAc2 species. In this paper, we demonstrate that the alpha1,2 mannosidase, which is involved in the processing of Man5GlcNAc2 into Man4GlcNAc2, is located in the rough endoplasmic reticulum. The enzyme was shown to be inhibited by kifunensine and deoxymannojirimycin, indicating that it is a class I mannosidase. In addition, Man4GlcNAc2 species were produced at the expense of Glc1Man5GlcNAc2 species. Thus, the trimming of Man5GlcNAc2 to Man4GlcNAc2, which is catalyzed by this mannosidase, could be involved in the control of the glucose-dependent folding pathway.
The diphtheria toxin transmembrane domain as a pH sensitive membrane anchor for human interleukin-2 and murine interleukin-3.

PubMed

Liger, D; Nizard, P; Gaillard, C; vanderSpek, J C; Murphy, J R; Pitard, B; Gillet, D

1998-11-01

We have constructed two fusion proteins T-hIL-2 and T-mIL-3 in which human interleukin-2 (hIL-2) or murine interleukin-3 (mIL-3) are fused to the C-terminus of the diphtheria toxin transmembrane domain (T domain). Two additional fusion proteins, T-(Gly4-Ser)2-hIL-2 and T-(Gly4-Ser)2-mIL-3, were derived by introduction of the (Gly4-Ser)2 spacer between the T domain and cytokine components. Recognition of the hIL-2 receptor or the mIL-3 receptor by the corresponding recombinant proteins was demonstrated by their capacity to stimulate cytokine-dependent cell lines. All proteins retained the capacity of the T domain to insert into phospholipid membranes at acidic pH. Finally, anchoring of both cytokines to the membrane of lipid vesicles or living cells was assessed by specific antibody recognition. Our results show that the T domain fused to the N-terminus of a given protein can function as a pH sensitive membrane anchor for that protein.
Plasmid-determined cytotoxicity in Yersinia pestis and Yersinia pseudotuberculosis.

PubMed Central

Goguen, J D; Walker, W S; Hatch, T P; Yother, J

1986-01-01

Yersinia pestis KIM5 was found to be cytotoxic for the IC21 and P388D1 mouse macrophage cell lines, as well as for resident peritoneal macrophages from C57BL/6 mice. Affected cells phagocytosed KIM5 inefficiently, became spherical, detached readily from culture dishes, and retained 51Cr poorly. The cytotoxic effect was dependent on the presence of the 75-kilobase plasmid pCD1. Because this plasmid also encodes the low calcium response (LCR), three Mu d1 insertion mutants previously shown to be LCR- and of reduced virulence in mice were examined for cytotoxicity; all were found to be atoxic. The insertions in these mutants lie within three distinct LCR loci (lcrB, C, and D). Like LCR, cytotoxicity was expressed only at 37 degrees C. Unlike LCR, it was not influenced by Ca2+ concentration, indicating that the V and W antigens are probably not involved. Yersinia pseudotuberculosis was found to have a similar plasmid-dependent cytotoxicity. Thus, biological activity observed as cytotoxicity in vitro may well be a common feature contributing to virulence of the yersiniae. Images PMID:3949380
Understanding the size and character of fouling-causing substances from effluent organic matter (EfOM) in low-pressure membrane filtration.

PubMed

Laabs, Claudia N; Amy, Gary L; Jekel, Martin

2006-07-15

Stirred cell tests with microfiltration (MF) and ultrafiltration (UF) membranes show high flux decline for WWTP effluents. For the MF membrane, for example, the flux declines within 15 min to 70-80% of the initial flux (J0 is in the range of 1000 L/m2h to 1500 L/m2h). This time corresponds to the filtration of a cumulative volume of 110 L/m2. Feed and permeate samples of the stirred cell tests are analyzed by size-exclusion chromatography (SEC) with on-line organic carbon and UVA254 detection. The resulting chromatograms exhibit a clear difference between the feed and permeate samples in the so-called polysaccharide (PS) peak. The substances eluting in the PS peak (organic colloids, polysaccharides, and proteins) are retained completely by UF membranes and partly by MF membranes, and are responsible for the observed fouling. By sequential filtration experiments the sizes of these macromolecules are determined to be in the range of 10 to 100 nm.
CLO: The cell line ontology

PubMed Central

2014-01-01

Background Cell lines have been widely used in biomedical research. The community-based Cell Line Ontology (CLO) is a member of the OBO Foundry library that covers the domain of cell lines. Since its publication two years ago, significant updates have been made, including new groups joining the CLO consortium, new cell line cells, upper level alignment with the Cell Ontology (CL) and the Ontology for Biomedical Investigation, and logical extensions. Construction and content Collaboration among the CLO, CL, and OBI has established consensus definitions of cell line-specific terms such as ‘cell line’, ‘cell line cell’, ‘cell line culturing’, and ‘mortal’ vs. ‘immortal cell line cell’. A cell line is a genetically stable cultured cell population that contains individual cell line cells. The hierarchical structure of the CLO is built based on the hierarchy of the in vivo cell types defined in CL and tissue types (from which cell line cells are derived) defined in the UBERON cross-species anatomy ontology. The new hierarchical structure makes it easier to browse, query, and perform automated classification. We have recently added classes representing more than 2,000 cell line cells from the RIKEN BRC Cell Bank to CLO. Overall, the CLO now contains ~38,000 classes of specific cell line cells derived from over 200 in vivo cell types from various organisms. Utility and discussion The CLO has been applied to different biomedical research studies. Example case studies include annotation and analysis of EBI ArrayExpress data, bioassays, and host-vaccine/pathogen interaction. CLO’s utility goes beyond a catalogue of cell line types. The alignment of the CLO with related ontologies combined with the use of ontological reasoners will support sophisticated inferencing to advance translational informatics development. PMID:25852852
Contribution of direct electron transfer mechanisms to overall electron transfer in microbial fuel cells utilising Shewanella oneidensis as biocatalyst.

PubMed

Fapetu, Segun; Keshavarz, Taj; Clements, Mark; Kyazze, Godfrey

2016-09-01

To investigate the contribution of direct electron transfer mechanisms to electricity production in microbial fuel cells by physically retaining Shewanella oneidensis cells close to or away from the anode electrode. A maximum power output of 114 ± 6 mWm(-2) was obtained when cells were retained close to the anode using a dialysis membrane. This was 3.5 times more than when the cells were separated away from the anode. Without the membrane the maximum power output was 129 ± 6 mWm(-2). The direct mechanisms of electron transfer contributed significantly to overall electron transfer from S. oneidensis to electrodes, a result that was corroborated by another experiment where S. oneidensis cells were entrapped in alginate gels. S. oneidensis transfers electrons primarily by direct electron transfer as opposed to mediated electron transfer.
YKL-40 is differentially expressed in human embryonic stem cells and in cell progeny of the three germ layers.

PubMed

Brøchner, Christian B; Johansen, Julia S; Larsen, Lars A; Bak, Mads; Mikkelsen, Hanne B; Byskov, Anne Grete; Andersen, Claus Yding; Møllgård, Kjeld

2012-03-01

The secreted glycoprotein YKL-40 participates in cell differentiation, inflammation, and cancer progression. High YKL-40 expression is reported during early human development, but its functions are unknown. Six human embryonic stem cell (hESC) lines were cultured in an atmosphere of low or high oxygen tension, in culture medium with or without basic fibroblast growth factor, and on feeder layers comprising mouse embryonic fibroblasts or human foreskin fibroblasts to evaluate whether hESCs and their progeny produced YKL-40 and to characterize YKL-40 expression during differentiation. Secreted YKL-40 protein and YKL-40 mRNA expression were measured by enzyme-linked immunosorbent assay (ELISA) and quantitative RT-PCR. Serial-sectioned colonies were stained for YKL-40 protein and for pluripotent hESC (OCT4, NANOG) and germ layer (HNF-3β, PDX1, CD34, p63, nestin, PAX6) markers. Double-labeling showed YKL-40 expression in OCT4-positive hESCs, PAX6-positive neuroectodermal cells, and HNF-3β-positive endodermal cells. The differentiating progeny showed strong YKL-40 expression. Abrupt transition between YKL-40 and OCT4-positive hESCs and YKL-40-positive ecto- and neuroectodermal lineages was observed within the same epithelial-like layer. YKL-40-positive cells within deeper layers lacked contact with OCT4-positive cells. YKL-40 may be important in initial cell differentiation from hESCs toward ectoderm and neuroectoderm, with retained epithelial morphology, whereas later differentiation into endoderm and mesoderm involves a transition into the deeper layers of the colony.
Energy independent uptake and release of polystyrene nanoparticles in primary mammalian cell cultures.

PubMed

Fiorentino, Ilaria; Gualtieri, Roberto; Barbato, Vincenza; Mollo, Valentina; Braun, Sabrina; Angrisani, Alberto; Turano, Mimmo; Furia, Maria; Netti, Paolo A; Guarnieri, Daniela; Fusco, Sabato; Talevi, Riccardo

2015-01-15

Nanoparticle (NPs) delivery systems in vivo promises to overcome many obstacles associated with the administration of drugs, vaccines, plasmid DNA and RNA materials, making the study of their cellular uptake a central issue in nanomedicine. The uptake of NPs may be influenced by the cell culture stage and the NPs physical-chemical properties. So far, controversial data on NPs uptake have been derived owing to the heterogeneity of NPs and the general use of immortalized cancer cell lines that often behave differently from each other and from primary mammalian cell cultures. Main aims of the present study were to investigate the uptake, endocytosis pathways, intracellular fate and release of well standardized model particles, i.e. fluorescent 44 nm polystyrene NPs (PS-NPs), on two primary mammalian cell cultures, i.e. bovine oviductal epithelial cells (BOEC) and human colon fibroblasts (HCF) by confocal microscopy and spectrofluorimetric analysis. Different drugs and conditions that inhibit specific internalization routes were used to understand the mechanisms that mediate PS-NP uptake. Our data showed that PS-NPs are rapidly internalized by both cell types 1) with similar saturation kinetics; 2) through ATP-independent processes, and 3) quickly released in the culture medium. Our results suggest that PS-NPs are able to rapidly cross the cell membrane through passive translocation during both uptake and release, and emphasize the need to carefully design NPs for drug delivery, to ensure their selective uptake and to optimize their retainment in the targeted cells. Copyright © 2014 Elsevier Inc. All rights reserved.
Doing well by doing good. The 7 benefits of a meaningful corporate social responsibility program.

PubMed

Macdonald, Deborah

2008-08-01

You want your medical group to be a good community player--but you need to attract new patients, retain top staff and manage your bottom line. A corporate social responsibility program may be the shrewd solution.

Iterative sorting reveals CD133+ and CD133- melanoma cells as phenotypically distinct populations.

PubMed

Grasso, Carole; Anaka, Matthew; Hofmann, Oliver; Sompallae, Ramakrishna; Broadley, Kate; Hide, Winston; Berridge, Michael V; Cebon, Jonathan; Behren, Andreas; McConnell, Melanie J

2016-09-09

The heterogeneity and tumourigenicity of metastatic melanoma is attributed to a cancer stem cell model, with CD133 considered to be a cancer stem cell marker in melanoma as well as other tumours, but its role has remained controversial. We iteratively sorted CD133+ and CD133- cells from 3 metastatic melanoma cell lines, and observed tumourigenicity and phenotypic characteristics over 7 generations of serial xeno-transplantation in NOD/SCID mice. We demonstrate that iterative sorting is required to make highly pure populations of CD133+ and CD133- cells from metastatic melanoma, and that these two populations have distinct characteristics not related to the cancer stem cell phenotype. In vitro, gene set enrichment analysis indicated CD133+ cells were related to a proliferative phenotype, whereas CD133- cells were of an invasive phenotype. However, in vivo, serial transplantation of CD133+ and CD133- tumours over 7 generations showed that both populations were equally able to initiate and propagate tumours. Despite this, both populations remained phenotypically distinct, with CD133- cells only able to express CD133 in vivo and not in vitro. Loss of CD133 from the surface of a CD133+ cell was observed in vitro and in vivo, however CD133- cells derived from CD133+ retained the CD133+ phenotype, even in the presence of signals from the tumour microenvironment. We show for the first time the necessity of iterative sorting to isolate pure marker-positive and marker-negative populations for comparative studies, and present evidence that despite CD133+ and CD133- cells being equally tumourigenic, they display distinct phenotypic differences, suggesting CD133 may define a distinct lineage in melanoma.
The characteristics and antigenic properties of recently emerged subclade 3C.3a and 3C.2a human influenza A(H3N2) viruses passaged in MDCK cells.

PubMed

Lin, Yipu; Wharton, Stephen A; Whittaker, Lynne; Dai, Mian; Ermetal, Burcu; Lo, Janice; Pontoriero, Andrea; Baumeister, Elsa; Daniels, Rodney S; McCauley, John W

2017-05-01

Two new subclades of influenza A(H3N2) viruses became prominent during the 2014-2015 Northern Hemisphere influenza season. The HA glycoproteins of these viruses showed sequence changes previously associated with alterations in receptor-binding properties. To address how these changes influence virus propagation, viruses were isolated and propagated in conventional MDCK cells and MDCK-SIAT1 cells, cells with enhanced expression of the human receptor for the virus, and analysed at each passage. Gene sequence analysis was undertaken as virus was passaged in conventional MDCK cells and MDCK-SIAT1 cells. Alterations in receptor recognition associated with passage of virus were examined by haemagglutination assays using red blood cells from guinea pigs, turkeys and humans. Microneutralisation assays were performed to determine how passage-acquired amino acid substitutions and polymorphisms affected virus antigenicity. Viruses were able to infect MDCK-SIAT1 cells more efficiently than conventional MDCK cells. Viruses of both the 3C.2a and 3C.3a subclades showed greater sequence change on passage in conventional MDCK cells than in MDCK-SIAT1 cells, with amino acid substitutions being seen in both HA and NA glycoproteins. However, virus passage in MDCK-SIAT1 cells at low inoculum dilutions showed reducing infectivity on continued passage. Current H3N2 viruses should be cultured in the MDCK-SIAT1 cell line to maintain faithful replication of the virus, and at an appropriate multiplicity of infection to retain infectivity. © 2017 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.
Attempted mechanical transfer of Ehrlichia risticii by tabanids (Diptera: Tabanidae).

PubMed

Levine, J F; Levy, M G; Nicholson, W L; Irby, W S; Gager, R; Apperson, C S

1992-09-01

The ability of tabanid mouthparts to retain and to transfer mechanically Ehrlichia risticii Holland, Weiss, Burgdorfer, Cole & Kakoma was evaluated by feeding flies on infected and noninfected mice and on capillary tubes containing infected cells and cell-free medium. Flies representing two genera and 29 species were collected at equine boarding stables, farms, and along riding trails in Wake, Johnston, and Duplin counties in North Carolina for the feeding trials. Two species, Tabanus fulvulus Wiedemann and T. pallidescens Philip, fed on mice but failed to transfer the pathogen from infected to susceptible mice. Chrysops vittatus Wiedemann, Tabanus americanus Forster, and T. sulcifrons Macquart transferred E. risticii-infected cells from capillary tubes containing infected cells in medium to tubes containing medium. These studies document that E. risticii-infected cells can be retained on mouthparts and potentially transferred by tabanids.
The technology of obtaining multipotent spheroids from limbal mesenchymal stromal cells for reparation of injured eye tissues.

PubMed

Kosheleva, N V; Saburina, I N; Zurina, I M; Gorkun, A A; Borzenok, S A; Nikishin, D A; Kolokoltsova, T D; Ustinova, E E; Repin, V S

2016-01-01

It is known that stem and progenitor cells open new possibilities for restoring injured eye tissues. Limbal eye zone, formed mainly by derivatives of neural crest, is the main source of stem cells for regeneration. The current study considers development of innovative technology for obtaining 3D spheroids from L-MMSC. It was shown that under 3D conditions L-MMSC due to compactization and mesenchymal-epithelial transition self-organize into cellular reparative modules. Formed L-MMSC spheroids retain and promote undifferentiated population of stem and progenitor limbal cells, as supported by expression of pluripotency markers - Oct4, Sox2, Nanog. Extracellular matrix synthetized by cells in spheroids allows retaining the functional potential of L-MMSC that are involved in regeneration of both anterior and, probably, posterior eye segment.
Curcumin-Loaded Blood-Stable Polymeric Micelles for Enhancing Therapeutic Effect on Erythroleukemia.

PubMed

Gong, Feirong; Chen, Dan; Teng, Xin; Ge, Junhua; Ning, Xianfeng; Shen, Ya-Ling; Li, Jian; Wang, Shanfeng

2017-08-07

Curcumin has high potential in suppressing many types of cancer and overcoming multidrug resistance in a multifaceted manner by targeting diverse molecular targets. However, the rather low systemic bioavailability resulted from its poor solubility in water and fast metabolism/excretion in vivo has hampered its applications in cancer therapy. To increase the aqueous solubility of curcumin while retaining the stability in blood circulation, here we report curcumin-loaded copolymer micelles with excellent in vitro and in vivo stability and antitumor efficacy. The two copolymers used for comparison were methoxy-poly(ethylene glycol)-block-poly(ε-caprolactone) (mPEG-PCL) and N-(tert-butoxycarbonyl)-l-phenylalanine end-capped mPEG-PCL (mPEG-PCL-Phe(Boc)). In vitro cytotoxicity evaluation against human pancreatic SW1990 cell line showed that the delivery of curcumin in mPEG-PCL-Phe(Boc) micelles to cancer cells was efficient and dosage-dependent. The pharmacokinetics in ICR mice indicated that intravenous (i.v.) administration of curcumin/mPEG-PCL-Phe(Boc) micelles could retain curcumin in plasma much better than curcumin/mPEG-PCL micelles. Biodistribution results in Sprague-Dawley rats also showed higher uptake and slower elimination of curcumin into liver, lung, kidney, and brain, and lower uptake into heart and spleen of mPEG-PCL-Phe(Boc) micelles, as compared with mPEG-PCL micelles. Further in vivo efficacy evaluation in multidrug-resistant human erythroleukemia K562/ADR xenograft model revealed that i.v. administration of curcumin-loaded mPEG-PCL-Phe(Boc) micelles significantly delayed tumor growth, which was attributed to the improved stability of curcumin in the bloodstream and increased systemic bioavailability. The mPEG-PCL-Phe(Boc) micellar system is promising in overcoming the key challenge of curcumin's to promote its applications in cancer therapy.
Design and Synthesis of Novel Arylketo-containing P1-P3 Linked Macro-cyclic BACE-1 Inhibitors

PubMed Central

Sandgren, Veronica; Belda, Oscar; Kvarnström, Ingemar; Lindberg, Jimmy; Samuelsson, Bertil; Dahlgren, Anders

2015-01-01

A series of arylketo-containing P1-P3 linked macrocyclic BACE-1 inhibitors were designed, synthesized, and compared with compounds with a previously known and extensively studied corresponding P2 isophthalamide moiety with the aim to improve on permeability whilst retaining the enzyme- and cell-based activities. Several inhibitors displayed substantial increases in Caco-2 cell-based permeability compared to earlier synthesized inhibitors and notably also with retained activities, showing that this approach might yield BACE-1 inhibitors with improved properties. PMID:25937848
Porous electrolyte retainer for molten carbonate fuel cell. [lithium aluminate

DOEpatents

Singh, R.N.; Dusek, J.T.

1979-12-27

A porous tile for retaining molten electrolyte within a fuel cell is prepared by sintering particles of lithium aluminate into a stable structure. The tile is assembled between two porous metal plates which serve as electrodes with fuels gases such as H/sub 2/ and CO opposite to oxidant gases such as O/sub 2/ and CO/sub 2/. The tile is prepared with a porosity of 55 to 65% and a pore size distribution selected to permit release of sufficient molten electrolyte to wet but not to flood the adjacent electrodes.
Porous electrolyte retainer for molten carbonate fuel cell

DOEpatents

Singh, Raj N.; Dusek, Joseph T.

1983-06-21

A porous tile for retaining molten electrolyte within a fuel cell is prepared by sintering particles of lithium aluminate into a stable structure. The tile is assembled between two porous metal plates which serve as electrodes with fuels gases such as H.sub.2 and CO opposite to oxidant gases such as O.sub.2 and CO.sub.2. The tile is prepared with a porosity of 55-65% and a pore size distribution selected to permit release of sufficient molten electrolyte to wet but not to flood the adjacent electrodes.
Thyroid cell lines in research on goitrogenesis.

PubMed

Gerber, H; Peter, H J; Asmis, L; Studer, H

1991-12-01

Thyroid cell lines have contributed a lot to the understanding of goitrogenesis. The cell lines mostly used in thyroid research are briefly discussed, namely the rat thyroid cell lines FRTL and FRTL-5, the porcine thyroid cell lines PORTHOS and ARTHOS, The sheep thyroid cell lines OVNIS 5H and 6H, the cat thyroid cell lines PETCAT 1 to 4 and ROMCAT, and the human thyroid cell lines FTC-133 and HTh 74. Chinese hamster ovary (CHO) cells and COS-7 cells, stably transfected with TSH receptor cDNA and expressing a functional TSH receptor, are discussed as examples for non-thyroidal cells, transfected with thyroid genes.
Assessment of toxic potential of mycotoxin contaminated bread during in vitro human digestion on human B lymphoid cell line.

PubMed

Monaci, Linda; Garbetta, Antonella; Angelis, Elisabetta De; Visconti, Angelo; Minervini, Fiorenza

2015-01-05

Ingestion of food is considered a major route of exposure to many contaminants including mycotoxins. The amount of mycotoxin resisting to the digestion process and potentially absorbable by the systemic circulation is only a smaller part of that ingested. In vitro digestion models turn useful for evaluating mycotoxins bioaccessibility during the intestinal transit and can be intended as a valuable tool for the assessment of mycotoxin bioavailability in food. In this paper we describe a study aimed at investigating toxicity of in vitro gastro-duodenal digests of mycotoxin contaminated bread collected along the digestion time-course. Toxicity tests were carried out on a sensitive RPMI lymphoid B cell line chosen as the most suitable lineage to assess toxicity retained by gastro-duodenal digests. In parallel, a chemical quantification of T-2 and HT-2 toxins contaminating the bread digests was accomplished during the gastric and duodenal transit. The digestive fluids undergoing chemical and toxicological analysis were collected at the beginning and end of gastric phase, and after completion of the duodenal phase. Results proved that a correlation between HT-2 content and toxicity did exist although a more persistent toxic activity was displayed in the later stage of the duodenal phase. This persistent toxicity might be explained by the co-occurrence of unknown HT-2-related conjugates or metabolites formed during digestion. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Analysis of renal cancer cell lines from two major resources enables genomics-guided cell line selection

NASA Astrophysics Data System (ADS)

Sinha, Rileen; Winer, Andrew G.; Chevinsky, Michael; Jakubowski, Christopher; Chen, Ying-Bei; Dong, Yiyu; Tickoo, Satish K.; Reuter, Victor E.; Russo, Paul; Coleman, Jonathan A.; Sander, Chris; Hsieh, James J.; Hakimi, A. Ari

2017-05-01

The utility of cancer cell lines is affected by the similarity to endogenous tumour cells. Here we compare genomic data from 65 kidney-derived cell lines from the Cancer Cell Line Encyclopedia and the COSMIC Cell Lines Project to three renal cancer subtypes from The Cancer Genome Atlas: clear cell renal cell carcinoma (ccRCC, also known as kidney renal clear cell carcinoma), papillary (pRCC, also known as kidney papillary) and chromophobe (chRCC, also known as kidney chromophobe) renal cell carcinoma. Clustering copy number alterations shows that most cell lines resemble ccRCC, a few (including some often used as models of ccRCC) resemble pRCC, and none resemble chRCC. Human ccRCC tumours clustering with cell lines display clinical and genomic features of more aggressive disease, suggesting that cell lines best represent aggressive tumours. We stratify mutations and copy number alterations for important kidney cancer genes by the consistency between databases, and classify cell lines into established gene expression-based indolent and aggressive subtypes. Our results could aid investigators in analysing appropriate renal cancer cell lines.
Engineering cholesterol-based fibers for antibody immobilization and cell capture

NASA Astrophysics Data System (ADS)

Cohn, Celine

In 2015, the United States is expected to have nearly 600,000 deaths attributed to cancer. Of these 600,000 deaths, 90% will be a direct result of cancer metastasis, the spread of cancer throughout the body. During cancer metastasis, circulating tumor cells (CTCs) are shed from primary tumors and migrate through bodily fluids, establishing secondary cancer sites. As cancer metastasis is incredibly lethal, there is a growing emphasis on developing "liquid biopsies" that can screen peripheral blood, search for and identify CTCs. One popular method for capturing CTCs is the use of a detection platform with antibodies specifically suited to recognize and capture cancer cells. These antibodies are immobilized onto the platform and can then bind and capture cells of interest. However, current means to immobilize antibodies often leave them with drastically reduced function. The antibodies are left poorly suited for cell capture, resulting in low cell capture efficiencies. This body of work investigates the use of lipid-based fibers to immobilize proteins in a way that retains protein function, ultimately leading to increased cell capture efficiencies. The resulting increased efficiencies are thought to arise from the retained three-dimensional structure of the protein as well as having a complete coating of the material surface with antibodies that are capable of interacting with their antigens. It is possible to electrospin cholesterol-based fibers that are similar in design to the natural cell membrane, providing proteins a more natural setting during immobilization. Such fibers have been produced from cholesterol-based cholesteryl succinyl silane (CSS). These fibers have previously illustrated a keen aptitude for retaining protein function and increasing cell capture. Herein the work focuses on three key concepts. First, a model is developed to understand the immobilization mechanism used by electrospun CSS fibers. The antibody immobilization and cell capturing abilities of the CSS fibers were compared to that of hydrophobic polycaprolactone (PCL) fibers and hydrophilic plasma-treated PCL fibers. Electrospun CSS fibers were found to immobilize equivalent amounts of protein as hydrophobically immobilized proteins. However, these proteins captured 6 times more cells, indicative of retained protein function. The second key concept was the design and fabrication of a hybridized lipid fiber. Lipid fibers provide improved protein function but fabrication difficulties have limited their adoption. Thus, we sought to fabricate a lipid-polymer hybrid that is easily fabricated while maintaining protein function. The hybrid fiber consists of a PCL backbone with conjugated CSS. The hybrid lipid fibers showed improved protein function. In addition, higher lipid concentrations were directly correlated to higher cell capture efficiencies. The third key concept was on the development of dually functionalized lipid fibers and understanding the resulting cell capture efficiencies. Many platforms are unable to simultaneously search for heterogeneous populations of CTCs -- the ability to dually functionalize cell-capturing platforms would address this technological weakness. Studies indicated that dually functionalizing the lipid fibers did not compromise the platforms' abilities to capture the cells of interest. Such dually functionalized fibers allow for a single cell-capture platform to successfully detect heterogeneous populations of CTCs. The body of work encompassed herein describes the use of lipid fibers for antibody immobilization and cell capture. Data from various projects indicate that the use of cholesterol-based fibers produced from electrospun CSS are well suited for protein immobilization. The CSS fibers are able to immobilize equivalent amounts of protein as compared to other immobilization techniques. However, the benefit of these fibers is illustrated by the strong cell-capturing efficiencies, indicating that the immobilized proteins are able to retain their function and selectively target cells of interest. The successful immobilization of proteins and their retained function allows for the development of increasingly sensitive cancer diagnostic tools that are able to screen for CTCs early on in the cancer disease cycle.
Solar Cell Modules With Improved Backskin

DOEpatents

Chevrefils, Andre; Grigore, Daniel Gheorghe

2001-01-23

The present invention relates to gas turbines and more particularly to a device for controlling the flow of cooling air through a flowpath in a turbine blade. The device can be inserted in the inlet opening of the blade flowpath and be retained therein. The device comprises a plug member for adjusting the flow of cooling air through the flowpath. The plug member comprises a retaining portion for retaining the plug member at the inlet opening of the flowpath and a blocking portion inserted within the flowpath for reducing the cross-sectional area of the inlet opening. Such a device is inexpensive and can be easily inserted in the inlet opening of a blade flowpath and retained therein.
Contrasting roles of the ABCG2 Q141K variant in prostate cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sobek, Kathryn M.; Cummings, Jessica L.; Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA

ABCG2 is a membrane transport protein that effluxes growth-promoting molecules, such as folates and dihydrotestosterone, as well as chemotherapeutic agents. Therefore it is important to determine how variants of ABCG2 affect the transporter function in order to determine whether modified treatment regimens may be necessary for patients harboring ABCG2 variants. Previous studies have demonstrated an association between the ABCG2 Q141K variant and overall survival after a prostate cancer diagnosis. We report here that in patients with recurrent prostate cancer, those who carry the ABCG2 Q141K variant had a significantly shorter time to PSA recurrence post-prostatectomy than patients homozygous for wild-typemore » ABCG2 (P=0.01). Transport studies showed that wild-type ABCG2 was able to efflux more folic acid than the Q141K variant (P<0.002), suggesting that retained tumoral folate contributes to the decreased time to PSA recurrence in the Q141K variant patients. In a seemingly conflicting study, it was previously reported that docetaxel-treated Q141K variant prostate cancer patients have a longer survival time. We found this may be due to less efficient docetaxel efflux in cells with the Q141K variant versus wild-type ABCG2. In human prostate cancer tissues, confocal microscopy revealed that all genotypes had a mixture of cytoplasmic and plasma membrane staining, with noticeably less staining in the two homozygous KK patients. In conclusion, the Q141K variant plays contrasting roles in prostate cancer: 1) by decreasing folate efflux, increased intracellular folate levels result in enhanced tumor cell proliferation and therefore time to recurrence decreases; and 2) in patients treated with docetaxel, by decreasing its efflux, intratumoral docetaxel levels and tumor cell drug sensitivity increase and therefore patient survival time increases. Taken together, these data suggest that a patient's ABCG2 genotype may be important when determining a personalized treatment plan. - Highlights: • The presence of ABCG2 Q141K variant decreases time to PSA recurrence. • Cells expressing the Q141K variant retain more folic acid than wild type. • Cells expressing the Q141K variant are more sensitive to docetaxel. • ABCG2 protein is repressed miR-519c and/or miR-520h in prostate cancer cell lines.« less
The effect of Me2SO overexposure during cryopreservation on HOS TE85 and hMSC viability, growth and quality.

PubMed

Morris, Timothy J; Picken, Andrew; Sharp, Duncan M C; Slater, Nigel K H; Hewitt, Christopher J; Coopman, Karen

2016-12-01

With the cell therapy industry continuing to grow, the ability to preserve clinical grade cells, including mesenchymal stem cells (MSCs), whilst retaining cell viability and function remains critical for the generation of off-the-shelf therapies. Cryopreservation of MSCs, using slow freezing, is an established process at lab scale. However, the cytotoxicity of cryoprotectants, like Me 2 SO, raises questions about the impact of prolonged cell exposure to cryoprotectant at temperatures >0 °C during processing of large cell batches for allogenic therapies prior to rapid cooling in a controlled rate freezer or in the clinic prior to administration. Here we show that exposure of human bone marrow derived MSCs to Me 2 SO for ≥1 h before freezing, or after thawing, degrades membrane integrity, short-term cell attachment efficiency and alters cell immunophenotype. After 2 h's exposure to Me 2 SO at 37 °C post-thaw, membrane integrity dropped to ∼70% and only ∼50% of cells retained the ability to adhere to tissue culture plastic. Furthermore, only 70% of the recovered MSCs retained an immunophenotype consistent with the ISCT minimal criteria after exposure. We also saw a similar loss of membrane integrity and attachment efficiency after exposing osteoblast (HOS TE85) cells to Me 2 SO before, and after, cryopreservation. Overall, these results show that freezing medium exposure is a critical determinant of product quality as process scale increases. Defining and reporting cell sensitivity to freezing medium exposure, both before and after cryopreservation, enables a fair judgement of how scalable a particular cryopreservation process can be, and consequently whether the therapy has commercial feasibility. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Epithelial Label-Retaining Cells Are Absent during Tooth Cycling in Salmo salar and Polypterus senegalus.

PubMed

Vandenplas, Sam; Willems, Maxime; Witten, P Eckhard; Hansen, Tom; Fjelldal, Per Gunnar; Huysseune, Ann

2016-01-01

The Atlantic salmon (Salmo salar) and African bichir (Polypterus senegalus) are both actinopterygian fish species that continuously replace their teeth without the involvement of a successional dental lamina. Instead, they share the presence of a middle dental epithelium: an epithelial tier enclosed by inner and outer dental epithelium. It has been hypothesized that this tier could functionally substitute for a successional dental lamina and might be a potential niche to house epithelial stem cells involved in tooth cycling. Therefore, in this study we performed a BrdU pulse chase experiment on both species to (1) determine the localization and extent of proliferating cells in the dental epithelial layers, (2) describe cell dynamics and (3) investigate if label-retaining cells are present, suggestive for the putative presence of stem cells. Cells proliferate in the middle dental epithelium, outer dental epithelium and cervical loop at the lingual side of the dental organ to form a new tooth germ. Using long chase times, both in S. salar (eight weeks) and P. senegalus (eight weeks and twelve weeks), we could not reveal the presence of label-retaining cells in the dental organ. Immunostaining of P. senegalus dental organs for the transcription factor Sox2, often used as a stem cell marker, labelled cells in the zone of outer dental epithelium which grades into the oral epithelium (ODE transition zone) and the inner dental epithelium of a successor only. The location of Sox2 distribution does not provide evidence for epithelial stem cells in the dental organ and, more specifically, in the middle dental epithelium. Comparison of S. salar and P. senegalus reveals shared traits in tooth cycling and thus advances our understanding of the developmental mechanism that ensures lifelong replacement.
Epithelial Label-Retaining Cells Are Absent during Tooth Cycling in Salmo salar and Polypterus senegalus

PubMed Central

Vandenplas, Sam; Willems, Maxime; Witten, P. Eckhard; Hansen, Tom; Fjelldal, Per Gunnar; Huysseune, Ann

2016-01-01

The Atlantic salmon (Salmo salar) and African bichir (Polypterus senegalus) are both actinopterygian fish species that continuously replace their teeth without the involvement of a successional dental lamina. Instead, they share the presence of a middle dental epithelium: an epithelial tier enclosed by inner and outer dental epithelium. It has been hypothesized that this tier could functionally substitute for a successional dental lamina and might be a potential niche to house epithelial stem cells involved in tooth cycling. Therefore, in this study we performed a BrdU pulse chase experiment on both species to (1) determine the localization and extent of proliferating cells in the dental epithelial layers, (2) describe cell dynamics and (3) investigate if label-retaining cells are present, suggestive for the putative presence of stem cells. Cells proliferate in the middle dental epithelium, outer dental epithelium and cervical loop at the lingual side of the dental organ to form a new tooth germ. Using long chase times, both in S. salar (eight weeks) and P. senegalus (eight weeks and twelve weeks), we could not reveal the presence of label-retaining cells in the dental organ. Immunostaining of P. senegalus dental organs for the transcription factor Sox2, often used as a stem cell marker, labelled cells in the zone of outer dental epithelium which grades into the oral epithelium (ODE transition zone) and the inner dental epithelium of a successor only. The location of Sox2 distribution does not provide evidence for epithelial stem cells in the dental organ and, more specifically, in the middle dental epithelium. Comparison of S. salar and P. senegalus reveals shared traits in tooth cycling and thus advances our understanding of the developmental mechanism that ensures lifelong replacement. PMID:27049953
Intravaginal infection with herpes simplex virus type-2 (HSV-2) generates a functional effector memory T cell population that persists in the murine genital tract.

PubMed

Tang, Vera A; Rosenthal, Kenneth L

2010-12-01

Although the female genital tract is the main portal of entry for sexually transmitted infections in women, we still have limited understanding of the generation, maintenance and characteristics of memory T cells in the local tissue. Here, we utilized a mouse model of intravaginal HSV-2 infection and tetramers against the immunodominant HSV glycoprotein B epitope recognized by CD8+ T cells to examine the generation, maintenance and characteristics of anti-HSV memory T cells in the genital tract following acute infection. Our results show that the highest percentage of HSVgB-specific CD8+ T cells was found in the genital tract compared to the spleen or iliac lymphnode. Indeed, although the actual number of CD8+ T cells contracted following viral clearance, approximately one quarter of the CD8+ population that remained in the genital tissue was HSVgB-specific. Memory gB-tetramer+CD8 T cells in the genital tract were positive for CD127 and KLRG1 and negative for CD62L and CCR7, thus confirming that HSV-specific CD8 cells were effector memory T cells that lack the capacity for homing to lymphoid tissues. Functionally, both memory CD8+ and CD4+ HSV-specific populations in the genital tract produced IFNγ when stimulated in vitro and CD4+ cells also produced TNFα. Genital HSVgB-specific memory T cells expressed tissue-homing integrins CD103 (αE integrin) and CD49a (VLA-1 or α1 integrin). Our findings suggest that HSV-specific memory T cells are retained in the genital tract, poised to act as an early line of defense against future virus encounter. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.
Omega-3 Eicosapentaenoic Acid Decreases CD133 Colon Cancer Stem-Like Cell Marker Expression While Increasing Sensitivity to Chemotherapy

PubMed Central

De Carlo, Flavia; Witte, Theodore R.; Hardman, W. Elaine; Claudio, Pier Paolo

2013-01-01

Colorectal cancer is the third leading cause of cancer-related death in the western world. In vitro and in vivo experiments showed that omega-3 polyunsaturated fatty acids (n-3 PUFAs) can attenuate the proliferation of cancer cells, including colon cancer, and increase the efficacy of various anticancer drugs. However, these studies address the effects of n-3 PUFAs on the bulk of the tumor cells and not on the undifferentiated colon cancer stem-like cells (CSLCs) that are responsible for tumor formation and maintenance. CSLCs have also been linked to the acquisition of chemotherapy resistance and to tumor relapse. Colon CSLCs have been immunophenotyped using several antibodies against cellular markers including CD133, CD44, EpCAM, and ALDH. Anti-CD133 has been used to isolate a population of colon cancer cells that retains stem cells properties (CSLCs) from both established cell lines and primary cell cultures. We demonstrated that the n-3 PUFA, eicosapentaenoic acid (EPA), was actively incorporated into the membrane lipids of COLO 320 DM cells. 25 uM EPA decreased the cell number of the overall population of cancer cells, but not of the CD133 (+) CSLCs. Also, we observed that EPA induced down-regulation of CD133 expression and up-regulation of colonic epithelium differentiation markers, Cytokeratin 20 (CK20) and Mucin 2 (MUC2). Finally, we demonstrated that EPA increased the sensitivity of COLO 320 DM cells (total population) to both standard-of-care chemotherapies (5-Fluorouracil and oxaliplatin), whereas EPA increased the sensitivity of the CD133 (+) CSLCs to only 5-Fluorouracil. PMID:23874993
Polyploid tumour cells elicit paradiploid progeny through depolyploidizing divisions and regulated autophagic degradation.

PubMed

Erenpreisa, Jekaterina; Salmina, Kristine; Huna, Anda; Kosmacek, Elizabeth A; Cragg, Mark S; Ianzini, Fiorenza; Anisimov, Alim P

2011-07-01

'Neosis' describes the process whereby p53 function-deficient tumour cells undergo self-renewal after genotoxic damage apparently via senescing ETCs (endopolyploid tumour cells). We previously reported that autophagic digestion and extrusion of DNA occurs in ETC and subsequently revealed that self-renewal transcription factors are also activated under these conditions. Here, we further studied this phenomenon in a range of cell lines after genotoxic damage induced by gamma irradiation, ETO (etoposide) or PXT (paclitaxel) treatment. These experiments revealed that chromatin degradation by autophagy was compatible with continuing mitotic activity in ETC. While the actively polyploidizing primary ETC produced early after genotoxic insult activated self-renewal factors throughout the polygenome, the secondary ETC restored after failed multipolar mitosis underwent subnuclei differentiation. As such, only a subset of subnuclei continued to express OCT4 and NANOG, while those lacking these factors stopped DNA replication and underwent degradation and elimination through autophagy. The surviving subnuclei sequestered nascent cytoplasm to form subcells, while being retained within the confines of the old ETC. Finally, the preformed paradiploid subcells became released from their linking chromosome bridges through autophagy and subsequently began cell divisions. These data show that 'neotic' ETC resulting from genotoxically damaged p53 function-deficient tumour cells develop through a heteronuclear system differentiating the polyploid genome into rejuvenated 'viable' subcells (which provide mitotically propagating paradiploid descendents) and subnuclei, which become degraded and eliminated by autophagy. The whole process reduces aneuploidy in descendants of ETC.

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