Allorecognition triggers autophagy and subsequent necrosis in the cnidarian Hydractinia symbiolongicarpus.

PubMed

Buss, Leo W; Anderson, Christopher; Westerman, Erica; Kritzberger, Chad; Poudyal, Monita; Moreno, Maria A; Lakkis, Fadi G

2012-01-01

Transitory fusion is an allorecognition phenotype displayed by the colonial hydroid Hydractinia symbiolongicarpus when interacting colonies share some, but not all, loci within the allorecognition gene complex (ARC). The phenotype is characterized by an initial fusion followed by subsequent cell death resulting in separation of the two incompatible colonies. We here characterize this cell death process using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and continuous in vivo digital microscopy. These techniques reveal widespread autophagy and subsequent necrosis in both colony and grafted polyp assays. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays and ultrastructural observations revealed no evidence of apoptosis. Pharmacological inhibition of autophagy using 3-methyladenine (3-MA) completely suppressed transitory fusion in vivo in colony assays. Rapamycin did not have a significant effect in the same assays. These results establish the hydroid allorecognition system as a novel model for the study of cell death.

Environmentally Induced Epigenetic Transgenerational Inheritance of Altered Sertoli Cell Transcriptome and Epigenome: Molecular Etiology of Male Infertility

PubMed Central

Guerrero-Bosagna, Carlos; Savenkova, Marina; Haque, Md. Muksitul; Nilsson, Eric; Skinner, Michael K.

2013-01-01

Environmental toxicants have been shown to induce the epigenetic transgenerational inheritance of adult onset disease, including testis disease and male infertility. The current study was designed to determine the impact of an altered sperm epigenome on the subsequent development of an adult somatic cell (Sertoli cell) that influences the onset of a specific disease (male infertility). A gestating female rat (F0 generation) was exposed to the agriculture fungicide vinclozolin during gonadal sex determination and then the subsequent F3 generation progeny used for the isolation of Sertoli cells and assessment of testis disease. As previously observed, enhanced spermatogenic cell apoptosis was observed. The Sertoli cells provide the physical and nutritional support for the spermatogenic cells. Over 400 genes were differentially expressed in the F3 generation control versus vinclozolin lineage Sertoli cells. A number of specific cellular pathways were identified to be transgenerationally altered. One of the key metabolic processes affected was pyruvate/lactate production that is directly linked to spermatogenic cell viability. The Sertoli cell epigenome was also altered with over 100 promoter differential DNA methylation regions (DMR) modified. The genomic features and overlap with the sperm DMR were investigated. Observations demonstrate that the transgenerational sperm epigenetic alterations subsequently alters the development of a specific somatic cell (Sertoli cell) epigenome and transcriptome that correlates with adult onset disease (male infertility). The environmentally induced epigenetic transgenerational inheritance of testis disease appears to be a component of the molecular etiology of male infertility. PMID:23555832

Cell cycle activation in p21 dependent pathway: An alternative mechanism of organophosphate induced dopaminergic neurodegeneration.

PubMed

Wani, Willayat Yousuf; Kandimalla, Ramesh J L; Sharma, Deep Raj; Kaushal, Alka; Ruban, Anand; Sunkaria, Aditya; Vallamkondu, Jayalakshmi; Chiarugi, Alberto; Reddy, P Hemachandra; Gill, Kiran Dip

2017-07-01

In the previous study, we demonstrated that dichlorvos induces oxidative stress in dopaminergic neuronal cells and subsequent caspase activation mediates apoptosis. In the present study, we evaluated the effect and mechanism of dichlorvos induced oxidative stress on cell cycle activation in NGF-differentiated PC12 cells. Dichlorvos exposure resulted in oxidative DNA damage along with activation of cell cycle machinery in differentiated PC12 cells. Dichlorvos exposed cells exhibited an increased expression of p53, cyclin-D1, pRb and decreased expression of p21suggesting a re-entry of differentiated cells into the cell cycle. Cell cycle analysis of dichlorvos exposed cells revealed a reduction of cells in the G 0 /G 1 phase of the cell cycle (25%), and a concomitant increase of cells in S phase (30%) and G2/M phase (43.3%) compared to control PC12 cells. Further, immunoblotting of cytochrome c, Bax, Bcl-2 and cleaved caspase-3 revealed that dichlorvos induces a caspase-dependent cell death in PC12 cells. These results suggest that Dichlorvos exposure has the potential to generate oxidative stress which evokes activation of cell cycle machinery leading to apoptotic cell death via cytochrome c release from mitochondria and subsequent caspase-3 activation in differentiated PC12 cells. Copyright © 2016 Elsevier B.V. All rights reserved.

Biofunctionalized 3-D Carbon Nano-Network Platform for Enhanced Fibroblast Cell Adhesion

NASA Astrophysics Data System (ADS)

Chowdhury, A. K. M. Rezaul Haque; Tavangar, Amirhossein; Tan, Bo; Venkatakrishnan, Krishnan

2017-03-01

Carbon nanomaterials have been investigated for various biomedical applications. In most cases, however, these nanomaterials must be functionalized biologically or chemically due to their biological inertness or possible cytotoxicity. Here, we report the development of a new carbon nanomaterial with a bioactive phase that significantly promotes cell adhesion. We synthesize the bioactive phase by introducing self-assembled nanotopography and altered nano-chemistry to graphite substrates using ultrafast laser. To the best of our knowledge, this is the first time that such a cytophilic bio-carbon is developed in a single step without requiring subsequent biological/chemical treatments. By controlling the nano-network concentration and chemistry, we develop platforms with different degrees of cell cytophilicity. We study quantitatively and qualitatively the cell response to nano-network platforms with NIH-3T3 fibroblasts. The findings from the in vitro study indicate that the platforms possess excellent biocompatibility and promote cell adhesion considerably. The study of the cell morphology shows a healthy attachment of cells with a well-spread shape, overextended actin filaments, and morphological symmetry, which is indicative of a high cellular interaction with the nano-network. The developed nanomaterial possesses great biocompatibility and considerably stimulates cell adhesion and subsequent cell proliferation, thus offering a promising path toward engineering various biomedical devices.

Combining bio-electrospraying with gene therapy: a novel biotechnique for the delivery of genetic material via living cells.

PubMed

Ward, Eliot; Chan, Emma; Gustafsson, Kenth; Jayasinghe, Suwan N

2010-05-01

The investigations reported in this article demonstrate the ability of bio-electrosprays and cell electrospinning to deliver a genetic construct in association with living cells. Previous studies on both bio-electrosprays and cell electrospinning demonstrated great promise for tissue engineering and regenerative biology/medicine. The investigations described herein widen the applicability of these biotechniques by combining gene therapy protocols, resulting in a novel drug delivery methodology previously unexplored. In these studies a human cell line was transduced with recombinant self-inactivating lentiviral particles. These particles incorporated a green fluorescent protein fused to an endosomal targeting construct. This construct encodes a peptide, which can subsequently be detected on the surface of cells by specific T-cells. The transduced cell line was subsequently manipulated in association with either bio-electrospraying or cell electrospinning. Hence this demonstrates (i) the ability to safely handle genetically modified living cells and (ii) the ability to directly form pre-determined architectures bearing living therapeutic cells. This merged technology demonstrates a unique approach for directly forming living therapeutic architectures for controlled and targeted release of experimental cells/genes, as well as medical cell/gene therapeutics for a plethora of biological and medical applications. Hence, such developments could be applied to personalised medicine.

Cell division versus cell elongation: the control of radicle elongation during thermoinhibition of Tagetes minuta achenes.

PubMed

Taylor, Nicky J; Hills, Paul N; van Staden, Johannes

2007-12-01

Endogenous embryo factors, which act mainly in the radicle, prevent germination in Tagetes minuta at high temperatures. These factors act to prevent cell elongation, which is critical for radicle protrusion under optimal conditions. Once the radicle has emerged both cell elongation and cell division are required for post-germination growth. Germination can be induced at high temperatures by fusicoccin, which rapidly stimulates cell elongation. In addition, priming seeds at 25 degrees C on polyethylene glycol (PEG) 6000 and mannitol could also induce germination on water at 36 degrees C, indicating that priming prevents radicle protrusion at a point subsequent to the point of control in thermoinhibited achenes. Flow cytometry studies revealed that DNA synthesis occurs during thermoinhibition and the inhibition of DNA synthesis during this process inhibits subsequent germination on water under optimal conditions, suggesting a protective role for DNA synthesis in thermoinhibited achenes of T. minuta.

Protection against hydrogen peroxide cytotoxicity in rat-1 fibroblasts provided by the oncoprotein Bcl-2: maintenance of calcium homoeostasis is secondary to the effect of Bcl-2 on cellular glutathione.

PubMed Central

Rimpler, M M; Rauen, U; Schmidt, T; Möröy, T; de Groot, H

1999-01-01

The oncoprotein Bcl-2 protects cells against apoptosis, but the exact molecular mechanism that underlies this function has not yet been identified. Studying H2O2-induced cell injury in Rat-1 fibroblast cells, we observed that Bcl-2 had a protective effect against the increase in cytosolic calcium concentration and subsequent cell death. Furthermore, overexpression of Bcl-2 resulted in an alteration of cellular glutathione status: the total amount of cellular glutathione was increased by about 60% and the redox potential of the cellular glutathione pool was maintained in a more reduced state during H2O2 exposure compared with non-Bcl-2-expressing controls. In our cytotoxicity model, disruption of cellular glutathione homoeostasis closely correlated with the pathological elevation of cytosolic calcium concentration. Stabilization of the glutathione pool by Bcl-2, N-acetylcysteine or glucose delayed the cytosolic calcium increase and subsequent cell death, whereas depletion of glutathione by dl-buthionine-(S, R)-sulphoximine, sensitized Bcl-2-transfected cells towards cytosolic calcium increase and cell death. We therefore suggest that the protection exerted by Bcl-2 against H2O2-induced cytosolic calcium elevation and subsequent cell death is secondary to its effect on the cellular glutathione metabolism. PMID:10229685

Efficacy of a randomized cell phone-based counseling intervention in postponing subsequent pregnancy among teen mothers.

PubMed

Katz, Kathy S; Rodan, Margaret; Milligan, Renee; Tan, Sylvia; Courtney, Lauren; Gantz, Marie; Blake, Susan M; McClain, Lenora; Davis, Maurice; Kiely, Michele; Subramanian, Siva

2011-12-01

Adolescent mothers in Washington, DC have a high rate of subsequent teen pregnancies, often within 24 months. Children of teen mothers are at risk for adverse psychosocial outcomes. When adolescents are strongly attached to parents, schools, and positive peers, they may be less likely to repeat a pregnancy. This study tested the efficacy of a counseling intervention delivered by cell phone and focused on postponing subsequent teen pregnancies by strengthening healthy relationships, reproductive practices, and positive youth assets. The objective of this study was to compare time to a repeat pregnancy between the intervention and usual care groups, and, secondarily, to determine whether treatment intensity influenced time to subsequent conception. Primiparous pregnant teens ages 15-19, were recruited in Washington, DC. Of 849 teens screened, 29.3% (n = 249) met inclusion criteria, consented to participate, and completed baseline measures. They were then randomized to the intervention (N = 124) or to usual care (N = 125). Intervention group teens received cell phones for 18 months of counseling sessions, and quarterly group sessions. Follow-up measures assessed subsequent pregnancy through 24 months post-delivery. A survival analysis compared time to subsequent conception in the two treatment groups. Additional models examined the effect of treatment intensity. By 24 months, 31% of the intervention and 36% of usual care group teens had a subsequent pregnancy. Group differences were not statistically significant in intent-to-treat analysis. Because there was variability in the degree of exposure of teens to the curriculum, a survival analysis accounting for treatment intensity was performed and a significant interaction with age was detected. Participants who were aged 15-17 years at delivery showed a significant reduction in subsequent pregnancy with increased levels of intervention exposure (P < 0.01), but not those ≥ 18 years. Adolescents ≥ 18 years faced considerable challenges to treatment success. Individual, social, and contextual factors are all important to consider in the prevention of repeat teen pregnancy. Cell phone-based approaches to counseling may not be the most ideal for addressing complex, socially-mediated behaviors such as this, except for selective subgroups. A lack of resources within the community for older teens may interfere with program success.

Subsequent vitiligo after hematopoietic stem cell transplantation: A nationwide population-based cohort study from Korea.

PubMed

Bae, Jung Min; Choi, Kwang Hyun; Jung, Han Mi; Kim, Sook Young; Kim, Miri; Kim, Gyung Moon; Yu, Dong Soo; Lee, Young Bok

2017-03-01

Subsequent vitiligo after hematopoietic stem cell transplantation (HSCT) has been described sporadically in case series. To investigate the incidence and risk factors of subsequent vitiligo after HSCT. A nationwide, population-based cohort study was performed using the Korean National Health Insurance Claims Database from 2009 to 2013. All HSCT recipients who had undergone HSCT between 2010 and 2011 and not treatment for vitiligo in 2009 (to exclude preexisting active vitiligo) were included in the HSCT recipient group, and an age- and sex-matched control group without HSCT was also established. A total of 2747 HSCT recipients and 8241 controls were enrolled. Newly acquired vitiligo occurred in 1.06% of HSCT recipients between 2010 and 2013, and there was a significant increase (OR 3.130, 95% CI 1.859-5.271) in cases of vitiligo in HSCT recipients compared with controls (0.34%). Allogeneic HSCT (OR 5.593, 95% CI 1.628-19.213) and bone marrow-sourced stem cells (as compared with peripheral blood-sourced stem cells; OR 2.492, 95% CI 1.114-5.576) were independently associated with the development of vitiligo after HSCT. Medical record review was not available. Vitiligo developed at a significantly increased rate after HSCT compared with controls. Allogeneic HSCT and bone marrow-sourced stem cells were independent risk factors. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Detection of increased choline compounds with proton nuclear magnetic resonance spectroscopy subsequent to malignant transformation of human prostatic epithelial cells.

PubMed

Ackerstaff, E; Pflug, B R; Nelson, J B; Bhujwalla, Z M

2001-05-01

In this study, a panel of normal human prostate cells (HPCs) and tumor cells derived from metastases were studied by (1)H NMR spectroscopy to determine whether the malignant transformation of HPCs results in the elevation of choline compounds. Although an elevated choline signal has been observed previously in clinical studies, the contribution of the different Cho compounds to this elevation, as well as their quantification, has not been established until now. Here we have shown that HPCs derived from metastases exhibit significantly higher phosphocholine as well as glycerophosphocholine levels compared with normal prostate epithelial and stromal cells. Thus the elevation of the choline peak observed clinically in prostate cancer is attributable to an alteration of phospholipid metabolism and not simply to increased cell density, doubling time, or other nonspecific effects. Androgen deprivation of the androgen receptor-positive cell lines resulted in a significant increase of choline compounds after chronic androgen deprivation of the LNCaP cell line and in a decrease of choline compounds after a more acute androgen deprivation of the LAPC-4 cell line. These data strongly support the use of proton magnetic resonance spectroscopic imaging to detect the presence of prostate cancer for diagnosis, to detect response subsequent to androgen ablation therapy, and to detect recurrence.

Growth, bioconversion of isoflavones and probiotic properties of parent and subsequent passages of Lactobacillus upon ultraviolet radiation.

PubMed

Yeo, Siok-Koon; Liong, Min-Tze

2012-11-01

The objective of this study was to evaluate the effects of ultraviolet (UV) radiation (UVB; 90 J/m²) on growth, bioconversion of isoflavones and probiotic properties of parent and subsequent passages of L. casei FTDC 2113. UV radiation significantly enhanced (P < 0.05) the growth of parent cells in mannitol-soymilk fermented at 37°C for 24 h. This had led to an enhanced intracellular and extracellular β-glucosidase activity with a subsequent increase in bioconversion of isoflavones in mannitol-soymilk (P < 0.05). UV radiation also promoted (P < 0.05) the tolerance of parent cells towards acidic condition (pH 2 and 3) and intestinal bile salts (oxgall, taurocholic and cholic acid). In addition, parent treated cells also exhibited better (P < 0.05) adhesion ability to mucin and antimicrobial activity compared to that of the control. All these positive effects of UV radiation were only prevalent in the parent cells without inheritance by first, second and third passage of cells. Although temporary, our results suggested that UV radiation could enhance the bioactive and probiotic potentials of L. casei FTDC 2113, and thus could be applied for the production of probiotic products with enhanced bioactivity.

Understanding clinical development of chimeric antigen receptor T cell therapies.

PubMed

de Wilde, Sofieke; Guchelaar, Henk-Jan; Zandvliet, Maarten Laurens; Meij, Pauline

2017-06-01

In the past decade, many clinical trials with gene- and cell-based therapies (GCTs) have been performed. Increased interest in the development of these drug products by various stakeholders has become apparent. Despite this growth in clinical studies, the number of therapies receiving marketing authorization approval (MAA) is lagging behind. To enhance the success rate of GCT development, it is essential to better understand the clinical development of these products. Chimeric antigen receptor (CAR) T cells are a GCT product subtype with promising efficacy in cancer treatment which are tested in many clinical trials, but have not yet received MAA. We generated an overview of the characteristics of CAR T-cell clinical development in the United States, Canada and Europe. Subsequently, the characteristics of clinical trials with CAR T-cell products that proceeded to a subsequent clinical trial, used as a proxy for success, were compared with those that did not proceed. From the U.S. and European Union clinical trial databases, 106 CAR T-cell trials were selected, from which 49 were linked to a subsequent trial and 57 were not. The majority of the trials had an academic sponsor from which most did not proceed, whereas most commercially sponsored trials were followed by another clinical trial. Furthermore, trials with a subsequent trial more frequently recruited large patient cohorts and were more often multicenter compared with trials that were not followed up. These characteristics can be used by investigators to better design clinical trials with CAR T cells. We encourage sponsors to plan clinical development ahead for a higher efficiency of product development and thereby achieving a higher success rate of development towards MAA. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Learning about the Unit Cell and Crystal Lattice with Computerized Simulations and Games: A Pilot Study

ERIC Educational Resources Information Center

Luealamai, Sutha; Panijpan, Bhinyo

2012-01-01

The authors have developed a computer-based learning module on the unit cell of various types of crystal. The module has two components: the virtual unit cell (VUC) part and the subsequent unit cell hunter part. The VUC is a virtual reality simulation for students to actively arrive at the unit cell from exploring, from a broad view, the crystal…

Transformation assay in Bhas 42 cells: a model using initiated cells to study mechanisms of carcinogenesis and predict carcinogenic potential of chemicals.

PubMed

Sasaki, Kiyoshi; Umeda, Makoto; Sakai, Ayako; Yamazaki, Shojiro; Tanaka, Noriho

2015-01-01

Transformation assays using cultured cells have been applied to the study of carcinogenesis. Although various cell systems exist, few cell types such as BALB/c 3T3 subclones and Syrian hamster embryo cells have been used to study chemically induced two-stage carcinogenesis. Bhas 42 cells were established as a clone by the transfection with the v-Ha-ras gene into mouse BALB/c 3T3 A31-1-1 cells and their subsequent selection based on their sensitivity to 12-O-tetradecanoylphorbol-13-acetate. Using Bhas 42 cells, transformed foci were induced by the treatment with nongenotoxic carcinogens, most of which act as tumor promoters. Therefore, Bhas 42 cells were considered to be a model of initiated cells. Subsequently, not only nongenotoxic carcinogens but also genotoxic carcinogens, most of which act as tumor initiators, were found to induce transformed foci by the modification of the protocol. Furthermore, transformation of Bhas 42 cells was induced by the transfection with genes of oncogenic potential. We interpret this high sensitivity of Bhas 42 cells to various types of carcinogenic stimuli to be related to the multistage model of carcinogenesis, as the transfection of v-Ha-ras gene further advances the parental BALB/c 3T3 A31-1-1 cells toward higher transforming potential. Thus, we propose that Bhas 42 cells are a novel and sensitive cell line for the analysis of carcinogenesis and can be used for the detection of not only carcinogenic substances but also gene alterations related to oncogenesis. This review will address characteristics of Bhas 42 cells, the transformation assay protocol, validation studies, and the various chemicals tested in this assay.

Rfx6 Directs Islet Formation and Insulin Production in Mice and Humans

PubMed Central

Smith, Stuart B.; Qu, Hui-Qi; Taleb, Nadine; Kishimoto, Nina; Scheel, David W.; Lu, Yang; Patch, Ann-Marie; Grabs, Rosemary; Wang, Juehu; Lynn, Francis C.; Miyatsuka, Takeshi; Mitchell, John; Seerke, Rina; Désir, Julie; Eijnden, Serge Vanden; Abramowicz, Marc; Kacet, Nadine; Weill, Jacques; Renard, Marie-Éve; Gentile, Mattia; Hansen, Inger; Dewar, Ken; Hattersley, Andrew T.; Wang, Rennian; Wilson, Maria E.; Johnson, Jeffrey D.; Polychronakos, Constantin; German, Michael S.

2009-01-01

Insulin from the β-cells of the pancreatic islets of Langerhans controls energy homeostasis in vertebrates, and its deficiency causes diabetes mellitus. During embryonic development, the transcription factor Neurogenin3 initiates the differentiation of the β-cells and other islet cell types from pancreatic endoderm, but the genetic program that subsequently completes this differentiation remains incompletely understood. Here we show that the transcription factor Rfx6 directs islet cell differentiation downstream of Neurogenin3. Mice lacking Rfx6 failed to generate any of the normal islet cell types except for pancreatic-polypeptide-producing cells. In human infants with a similar autosomal recessive syndrome of neonatal diabetes, genetic mapping and subsequent sequencing identified mutations in the human RFX6 gene. These studies demonstrate a unique position for Rfx6 in the hierarchy of factors that coordinate pancreatic islet development in both mice and humans. Rfx6 could prove useful in efforts to generate β-cells for patients with diabetes. PMID:20148032

Single-cell transcriptome conservation in cryopreserved cells and tissues.

PubMed

Guillaumet-Adkins, Amy; Rodríguez-Esteban, Gustavo; Mereu, Elisabetta; Mendez-Lago, Maria; Jaitin, Diego A; Villanueva, Alberto; Vidal, August; Martinez-Marti, Alex; Felip, Enriqueta; Vivancos, Ana; Keren-Shaul, Hadas; Heath, Simon; Gut, Marta; Amit, Ido; Gut, Ivo; Heyn, Holger

2017-03-01

A variety of single-cell RNA preparation procedures have been described. So far, protocols require fresh material, which hinders complex study designs. We describe a sample preservation method that maintains transcripts in viable single cells, allowing one to disconnect time and place of sampling from subsequent processing steps. We sequence single-cell transcriptomes from >1000 fresh and cryopreserved cells using 3'-end and full-length RNA preparation methods. Our results confirm that the conservation process did not alter transcriptional profiles. This substantially broadens the scope of applications in single-cell transcriptomics and could lead to a paradigm shift in future study designs.

The specificity of immune priming in silkworm, Bombyx mori, is mediated by the phagocytic ability of granular cells.

PubMed

Wu, Gongqing; Li, Mei; Liu, Yi; Ding, Ying; Yi, Yunhong

2015-10-01

In the past decade, the phenomenon of immune priming was documented in many invertebrates in a large number of studies; however, in most of these studies, behavioral evidence was used to identify the immune priming. The underlying mechanism and the degree of specificity of the priming response remain unclear. We studied the mechanism of immune priming in the larvae of the silkworm, Bombyx mori, and analyzed the specificity of the priming response using two closely related Gram-negative pathogenic bacteria (Photorhabdus luminescens TT01 and P. luminescens H06) and one Gram-positive pathogenic bacterium (Bacillus thuringiensis HD-1). Primed with heat-killed bacteria, the B. mori larvae were more likely to survive subsequent homologous exposure (the identical bacteria used in the priming and in the subsequent challenge) than heterologous (different bacteria used in the priming and subsequent exposure) exposure to live bacteria. This result indicated that the B. mori larvae possessed a strong immune priming response and revealed a degree of specificity to TT01, H06 and HD-1 bacteria. The degree of enhanced immune protection was positively correlated with the level of phagocytic ability of the granular cells and the antibacterial activity of the cell-free hemolymph. Moreover, the granular cells of the immune-primed larvae increased the phagocytosis of a previously encountered bacterial strain compared with other bacteria. Thus, the enhanced immune protection of the B. mori larvae after priming was mediated by the phagocytic ability of the granular cells and the antibacterial activity of the hemolymph; the specificity of the priming response was primarily attributed to the phagocytosis of bacteria by the granular cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cellular Injuries in Cronobacter sakazakii CIP 103183T and Salmonella enterica Exposed to Drying and Subsequent Heat Treatment in Milk Powder

PubMed Central

Lang, Emilie; Guyot, Stéphane; Peltier, Caroline; Alvarez-Martin, Pablo; Perrier-Cornet, Jean-Marie; Gervais, Patrick

2018-01-01

Because of the ability of foodborne pathogens to survive in low-moisture foods, their decontamination is an important issue in food protection. This study aimed to clarify some of the cellular mechanisms involved in inactivation of foodborne pathogens after drying and subsequent heating. Individual strains of Salmonella Typhimurium, Salmonella Senftenberg, and Cronobacter sakazakii were mixed into whole milk powder and dried to different water activity levels (0.25 and 0.58); the number of surviving cells was determined after drying and subsequent thermal treatments in closed vessels at 90 and 100°C, for 30 and 120 s. For each condition, the percentage of unculturable cells was estimated and, in parallel, membrane permeability and respiratory activity were estimated by flow cytometry using fluorescent probes. After drying, it was clearly observable that the percentage of unculturable cells was correlated with the percentage of permeabilized cells (responsible for 20–40% of the total inactivated bacteria after drying), and to a lesser degree with the percentage of cells presenting with loss of respiratory activity. In contrast, the percentages of unculturable cells observed after heat treatment were strongly correlated with the loss of respiratory activity and weakly with membrane permeability (for 70–80% of the total inactivated bacteria after heat treatment). We conclude that cell inactivation during drying is closely linked to membrane permeabilization and that heat treatment of dried cells affects principally their respiratory activity. These results legitimize the use of time–temperature scales and allow better understanding of the cellular mechanisms of bacterial death during drying and subsequent heat treatment. These results may also allow better optimization of the decontamination process to ensure food safety by targeting the most deleterious conditions for bacterial cells without denaturing the food product. PMID:29593704

Isolation of Primary Human Skeletal Muscle Cells

PubMed Central

Spinazzola, Janelle M.; Gussoni, Emanuela

2017-01-01

Primary myoblast culture is a valuable tool in research of muscle disease, pathophysiology, and pharmacology. This protocol describes techniques for dissociation of cells from human skeletal muscle biopsies and enrichment for a highly myogenic population by fluorescence-activated cell sorting (FACS). We also describe methods for assessing myogenicity and population expansion for subsequent in vitro study. PMID:29152538

Specific induction of neuronal cells from bone marrow stromal cells and application for autologous transplantation

PubMed Central

Dezawa, Mari; Kanno, Hiroshi; Hoshino, Mikio; Cho, Hirotomi; Matsumoto, Naoya; Itokazu, Yutaka; Tajima, Nobuyoshi; Yamada, Hitoshi; Sawada, Hajime; Ishikawa, Hiroto; Mimura, Toshirou; Kitada, Masaaki; Suzuki, Yoshihisa; Ide, Chizuka

2004-01-01

Bone marrow stromal cells (MSCs) have the capability under specific conditions of differentiating into various cell types such as osteocytes, chondrocytes, and adipocytes. Here we demonstrate a highly efficient and specific induction of cells with neuronal characteristics, without glial differentiation, from both rat and human MSCs using gene transfection with Notch intracellular domain (NICD) and subsequent treatment with bFGF, forskolin, and ciliary neurotrophic factor. MSCs expressed markers related to neural stem cells after transfection with NICD, and subsequent trophic factor administration induced neuronal cells. Some of them showed voltage-gated fast sodium and delayed rectifier potassium currents and action potentials compatible with characteristics of functional neurons. Further treatment of the induced neuronal cells with glial cell line–derived neurotrophic factor (GDNF) increased the proportion of tyrosine hydroxylase–positive and dopamine-producing cells. Transplantation of these GDNF-treated cells showed improvement in apomorphine-induced rotational behavior and adjusting step and paw-reaching tests following intrastriatal implantation in a 6-hydroxy dopamine rat model of Parkinson disease. This study shows that a population of neuronal cells can be specifically generated from MSCs and that induced cells may allow for a neuroreconstructive approach. PMID:15199405

Ku70 inhibits gemcitabine-induced DNA damage and pancreatic cancer cell apoptosis

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

Ma, Jiali; Hui, Pingping; Meng, Wenying

The current study focused on the role of Ku70, a DNA-dependent protein kinase (DNA-PK) complex protein, in pancreatic cancer cell resistance to gemcitabine. In both established cell lines (Mia-PaCa-2 and PANC-1) and primary human pancreatic cancer cells, shRNA/siRNA-mediated knockdown of Ku70 significantly sensitized gemcitabine-induced cell death and proliferation inhibition. Meanwhile, gemcitabine-induced DNA damage and subsequent pancreatic cancer cell apoptosis were also potentiated with Ku70 knockdown. On the other hand, exogenous overexpression of Ku70 in Mia-PaCa-2 cells suppressed gemcitabine-induced DNA damage and subsequent cell apoptosis. In a severe combined immune deficient (SCID) mice Mia-PaCa-2 xenograft model, gemcitabine-induced anti-tumor activity was remarkably pontificatedmore » when combined with Ku70 shRNA knockdown in the xenografts. The results of this preclinical study imply that Ku70 might be a primary resistance factor of gemcitabine, and Ku70 silence could significantly chemo-sensitize gemcitabine in pancreatic cancer cells. - Highlights: • Ku70 knockdown sensitizes gemcitabine-induced killing of pancreatic cancer cells. • Ku70 knockdown facilitates gemcitabine-induced DNA damage and cell apoptosis. • Ku70 overexpression deceases gemcitabine's sensitivity in pancreatic cancer cells. • Ku70 knockdown sensitizes gemcitabine-induced anti-tumor activity in vivo.« less

Mast cell hyperactivity underpins the development of oxygen-induced retinopathy

PubMed Central

Matsuda, Kenshiro; Okamoto, Noriko; Kondo, Masatoshi; Arkwright, Peter D.; Karasawa, Kaoru; Ishizaka, Saori; Yokota, Shinichi; Matsuda, Akira; Jung, Kyungsook; Oida, Kumiko; Jang, Hyosun; Noda, Eiichiro; Kakinuma, Ryota; Yasui, Koujirou; Kaku, Uiko; Mori, Yasuo; Onai, Nobuyuki; Ohteki, Toshiaki; Tanaka, Akane

2017-01-01

Mast cells are classically thought to play an important role in protection against helminth infections and in the induction of allergic diseases; however, recent studies indicate that these cells also contribute to neovascularization, which is critical for tissue remodeling, chronic inflammation, and carcinogenesis. Here, we demonstrate that mast cells are essential for sprouting angiogenesis in a murine model of oxygen-induced retinopathy (OIR). Although mouse strains lacking mast cells did not exhibit retinal neovascularization following hypoxia, these mice developed OIR following infusion of mast cells or after injection of mast cell tryptase (MCT). Relative hypoxia stimulated mast cell degranulation via transient receptor potential ankyrin 1. Subsequent surges in MCT stimulated retinal endothelial cells to produce monocyte chemotactic protein-1 (MCP1) and angiogenic factors, leading to sprouting angiogenesis. Mast cell stabilizers as well as specific tryptase and MCP1 inhibitors prevented the development of OIR in WT mice. Preterm infants with early retinopathy of prematurity had markedly higher plasma MCT levels than age-matched infants without disease, suggesting mast cells contribute to human disease. Together, these results suggest therapies that suppress mast cell activity should be further explored as a potential option for preventing eye diseases and subsequent blindness induced by neovascularization. PMID:28990934

Screening frequency and atypical cells and the prediction of cervical cancer risk.

PubMed

Chen, Yun-Yuan; You, San-Lin; Koong, Shin-Lan; Liu, Jessica; Chen, Chi-An; Chen, Chien-Jen

2014-05-01

To evaluate the screening efficacy and importance of atypical squamous cells and atypical glandular cells in predicting subsequent cervical cancer risk. This national cohort study in Taiwan analyzed associations between Pap test screening frequency and findings in 1995-2000 and subsequent risk of squamous cell carcinoma and adenocarcinoma after 2002. Women aged 30 years or older in 1995 without a cervical cancer history were included. Multivariate-adjusted hazard ratios and their 95% confidence intervals (CIs) were assessed using Cox regression analysis. During a total follow-up of 31,693,980 person-years in 2002-2008, 9,471 squamous cell carcinoma and 1,455 adenocarcinoma cases were newly diagnosed, resulting in 2,067 deaths. The risk of developing and dying from squamous cell carcinoma decreased significantly with increasing attendance frequency between 1995 and 2000 (all P values for trend<.001). Women who attended more than three screenings in 1995-2000 had 0.69-fold and 0.35-fold decrease in incidence and mortality of adenocarcinoma, respectively, compared with women who never attended any screenings. Abnormal cytologic findings were significant predictors of the incidence and mortality of cervical cancers. The adjusted hazard ratio (95% CI) of developing squamous cell carcinoma was 29.94 (22.83-39.25) for atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesions, and the adjusted hazard ratio (95% CI) of developing adenocarcinoma was 49.43 (36.49-66.97) for atypical glandular cells. Significant reductions in cervical adenocarcinoma occurred in women who attend three or more annual screenings in 6 years. High-grade atypical squamous cells and atypical glandular cells are important predictors of subsequent adenocarcinoma and squamous cell carcinoma. II.

Peripheral natural killer cytotoxicity and CD56(pos)CD16(pos) cells increase during early pregnancy in women with a history of recurrent spontaneous abortion.

PubMed

Emmer, P M; Nelen, W L; Steegers, E A; Hendriks, J C; Veerhoek, M; Joosten, I

2000-05-01

For diagnostic purposes we assessed peripheral natural killer (NK) cell cytotoxicity and NK and T cell numbers to assess their putative predictive value in recurrent spontaneous abortion (RSA). A total of 43 women with subsequent pregnancy, 37 healthy controls and 39 women successfully partaking in an in-vitro fertilization (IVF) procedure, were included in the study. We show that before pregnancy, levels of NK cytotoxicity and numbers of both single CD56(pos) and double CD56(pos)CD16(pos) cells were similar between RSA women and controls. But notably, within the RSA group, NK cell numbers of <12% were strongly associated with a subsequent pregnancy carried to term. Supplementation of folic acid led to an increase of single CD56(pos) cells, but cytotoxic function appeared unaffected. The expression pattern of killer inhibitory receptors on CD56(pos) cells was not different between patients and controls. A longitudinal study revealed that, compared with controls, in RSA women higher numbers of double CD56(pos)CD16(pos) cells were present during early pregnancy, paralleled by an increase in cytotoxic NK cell reactivity. The single CD56(pos) population decreased in number. In conclusion, the analysis of peripheral NK cell characteristics appears a suitable diagnostic tool in RSA. Immunomodulation aimed at NK cell function appears a promising therapeutic measure.

A threshold dose distribution approach for the study of PDT resistance development: A threshold distribution approach for the study of PDT resistance.

PubMed

de Faria, Clara Maria Gonçalves; Inada, Natalia Mayumi; Vollet-Filho, José Dirceu; Bagnato, Vanderlei Salvador

2018-05-01

Photodynamic therapy (PDT) is a technique with well-established principles that often demands repeated applications for sequential elimination of tumor cells. An important question concerns the way surviving cells from a treatment behave in the subsequent one. Threshold dose is a core concept in PDT dosimetry, as the minimum amount of energy to be delivered for cell destruction via PDT. Concepts of threshold distribution have shown to be an important tool for PDT results analysis in vitro. In this study, we used some of these concepts for demonstrating subsequent treatments with partial elimination of cells modify the distribution, which represents an increased resistance of the cells to the photodynamic action. HepG2 and HepaRG were used as models of tumor and normal liver cells and a protocol to induce resistance, consisted of repeated PDT sessions using Photogem® as a photosensitizer, was applied to the tumor ones. The response of these cells to PDT was assessed using a standard viability assay and the dose response curves were used for deriving the threshold distributions. The changes in the distribution revealed that the resistance protocol effectively eliminated the most sensitive cells. Nevertheless, HepaRG cell line was the most resistant one among the cells analyzed, which indicates a specificity in clinical applications that enables the use of high doses and drug concentrations with minimal damage to the surrounding normal tissue. Copyright © 2018 Elsevier B.V. All rights reserved.

Characterizing parameters of Jatropha curcas cell cultures for microgravity studies

NASA Astrophysics Data System (ADS)

Vendrame, Wagner A.; Pinares, Ania

2013-06-01

Jatropha (Jatropha curcas) is a tropical perennial species identified as a potential biofuel crop. The oil is of excellent quality and it has been successfully tested as biodiesel and in jet fuel mixes. However, studies on breeding and genetic improvement of jatropha are limited. Space offers a unique environment for experiments aiming at the assessment of mutations and differential gene expression of crops and in vitro cultures of plants are convenient for studies of genetic variation as affected by microgravity. However, before microgravity studies can be successfully performed, pre-flight experiments are necessary to characterize plant material and validate flight hardware environmental conditions. Such preliminary studies set the ground for subsequent spaceflight experiments. The objectives of this study were to compare the in vitro growth of cultures from three explant sources (cotyledon, leaf, and stem sections) of three jatropha accessions (Brazil, India, and Tanzania) outside and inside the petriGAP, a modified group activation pack (GAP) flight hardware to fit petri dishes. In vitro jatropha cell cultures were established in petri dishes containing a modified MS medium and maintained in a plant growth chamber at 25 ± 2 °C in the dark. Parameters evaluated were surface area of the explant tissue (A), fresh weight (FW), and dry weight (DW) for a period of 12 weeks. Growth was observed for cultures from all accessions at week 12, including subsequent plantlet regeneration. For all accessions differences in A, FW and DW were observed for inside vs. outside the PetriGAPs. Growth parameters were affected by accession (genotype), explant type, and environment. The type of explant influenced the type of cell growth and subsequent plantlet regeneration capacity. However, overall cell growth showed no abnormalities. The present study demonstrated that jatropha in vitro cell cultures are suitable for growth inside PetriGAPs for a period of 12 weeks. The parameters evaluated in this study provide the basic ground work and pre-flight assessment needed to justify a model for microgravity studies with jatropha in vitro cell cultures. Future studies should focus on results of experiments performed with jatropha in vitro cultures in microgravity.

Phagocytosis: studies by optical tweezers and time-resolved microspectrofluorometry

NASA Astrophysics Data System (ADS)

Schneckenburger, Herbert; Sailer, Reinhard; Hendinger, Anita; Gschwend, Michael H.; Bauer, Manfred; Strauss, Wolfgang S. L.

1999-01-01

Cellular uptake of transparent Latex particles by J774A.1 mouse macrophages has been studied: First, single beads were kept within an optical light trap and located in close vicinity to individual cells. Uptake of the beads was visualized, and intrinsic fluorescence was detected in the spectral range of 420 - 530 nm. Second, time-gated fluorescence spectra of single cells were recorded at pre- selected times during one hour after cellular uptake. A rapid increase of autofluorescence and a subsequent decrease to the level of control cells within about 10 min. was measured within a time gate of 0 - 5 ns after the exciting laser pulses, and attributed to the 'free' coenzyme NAD(P)H. In contrast, fluorescence increase of NAD(P)H bound to proteins (measured within time gates of 5 - 10 ns or 10 - 15 ns) was less pronounced, and the subsequent decrease occurred within a longer period (about one hour).

Gliogenesis: historical perspectives, 1839-1985.

PubMed

Webster, Henry deF; Aström, Karl E

2009-01-01

This historical review of gliogenesis begins with Schwann's introduction of the cell doctrine in 1839. Subsequent microscopic studies revealed the cellular structure of many organs and tissues, but the CNS was thought to be different. In 1864, Virchow created the concept that nerve cells are held together by a "Nervenkitte" which he called"glia" (for glue). He and his contemporaries thought that "glia" was an unstructured, connective tissue-like ground substance that separated nerve cells from each other and from blood vessels. Dieters, a pupil of Virchow, discovered that this ground substance contained cells, which he described and illustrated. Improvements in microscopes and discovery of metallic impregnation methods finally showed convincingly that the "glia" was not a binding substance. Instead, it was composed of cells, each separate and distinct from neighboring cells and each with its own characteristic array of processes. Light microscopic studies of developing and mature nervous tissue led to the discovery of different types of glial cells-astroglia, oligodendroglia, microglia, and ependymal cells in the CNS, and Schwann cells in the peripheral nervous system (PNS). Subsequent studies characterized the origins and development of each type of glial cell. A new era began with the introduction of electron microscopy, immunostaining, and in vitro maintenance of both central and peripheral nervous tissue. Other methods and models greatly expanded our understanding of how glia multiply, migrate, and differentiate. In 1985, almost a century and a half of study had produced substantial progress in our understanding of glial cells, including their origins and development. Major advances were associated with the discovery of new methods. These are summarized first. Then the origins and development of astroglia, oligodendroglia, microglia, ependymal cells, and Schwann cells are described and discussed. In general, morphology is emphasized. Findings related to cytodifferentiation, cellular interactions, functions, and regulation of developing glia have also been included.

An analytical biomarker for treatment of patients with recurrent B-ALL after remission induced by infusion of anti-CD19 chimeric antigen receptor T (CAR-T) cells.

PubMed

Zhang, Yajing; Zhang, Wenying; Dai, Hanren; Wang, Yao; Shi, Fengxia; Wang, Chunmeng; Guo, Yelei; Liu, Yang; Chen, Meixia; Feng, Kaichao; Zhang, Yan; Liu, Chuanjie; Yang, Qingming; Li, Suxia; Han, Weidong

2016-04-01

Anti-CD19 chimeric antigen receptor-modified T (CAR-T-19) cells have emerged as a powerful targeted immunotherapy for B-cell lineage acute lymphoblastic leukemia with a remarkable clinical response in recent trials. Nonetheless, few data are available on the subsequent clinical monitoring and treatment of the patients, especially those with disease recurrence after CAR-T-19 cell infusion. Here, we analyzed three patients who survived after our phase I clinical trial and who were studied by means of biomarkers reflecting persistence of CAR-T-19 cells in vivo and predictive factors directing further treatment. One patient achieved 9-week sustained complete remission and subsequently received an allogeneic hematopoietic stem cell transplant. Another patient who showed relapse after 20 weeks without detectable leukemia in the cerebrospinal fluid after CAR-T-19 cell treatment was able to achieve a morphological remission under the influence of stand-alone low-dose chemotherapeutic agents. The third patient gradually developed extensive extramedullary involvement in tissues with scarce immune- cell infiltration during a long period of hematopoietic remission after CAR-T-19 cell therapy. Long-term and discontinuous increases in serum cytokines (mainly interleukin 6 and C-reactive protein) were identified in two patients (Nos. 1 and 6) even though only a low copy number of CAR molecules could be detected in their peripheral blood. This finding was suggestive of persistent functional activity of CAR-T-19 cells. Combined analyses of laboratory biomarkers with their clinical manifestations before and after salvage treatment showed that the persistent immunosurveillance mediated by CAR-T-19 cells would inevitably potentiate the leukemia-killing effectiveness of subsequent chemotherapy in patients who showed relapse after CAR-T-19-induced remission.

Life sciences, biotechnology, and microgravity

NASA Technical Reports Server (NTRS)

Hymer, W. C.; Hayes, C.; Grindeland, R.; Lanhan, J. W.; Morrison, D.

1987-01-01

Growth hormone (GH) studies on rats flown aboard Spacelab 3 are discussed, and evidence for the direct effect of microgravity on cell function is reviewed. SL-3 rat GH cells were found to experience a secretory lesion (they contained more hormone per cell, but released less per cell relative to controls). Pituitary cell culture experiments on the STS-8 mission showed that GH cells did not subsequently release as much hormone as did control cells, indicating a secretory lesion. Changes in bone and muscle noted in SL-3 rats are related to GH cell findings.

Luteolin suppresses angiogenesis and vasculogenic mimicry formation through inhibiting Notch1-VEGF signaling in gastric cancer.

PubMed

Zang, Mingde; Hu, Lei; Zhang, Baogui; Zhu, Zhenglun; Li, Jianfang; Zhu, Zhenggang; Yan, Min; Liu, Bingya

2017-08-26

Gastric cancer is a great threat to the health of the people worldwide and lacks effective therapeutic regimens. Luteolin is one of Chinese herbs and presents in many fruits and green plants. In our previous study, we observed that luteolin inhibited cell migration and promoted cell apoptosis in gastric cancer. In the present study, luteolin significantly inhibited tube formation of human umbilical vein endothelial cells (HUVECs) through decreasing cell migration and proliferation of HUVECs in a dose-dependent manner. Vasculogenic mimicry (VM) tubes formed by gastric cancer cells were also inhibited with luteolin treatment. To explore how luteolin inhibited tubes formation, ELISA assay for VEGF was performed. Both of the VEGF secretion from Hs-746T cells and HUVECs were significantly decreased subsequent to luteolin treatment. In addition, cell migration was increased with the interaction between gastric cancer cells and HUVECs in co-culture assays. However, the promoting effects were abolished subsequent to luteolin treatment. Furthermore, luteolin inhibited VEGF secretion through suppressing Notch1 expression in gastric cancer. Overexpression of Notch1 in gastric cancer cells partially rescued the effects on cell migration, proliferation, HUVECs tube formation, and VM formation induced by luteolin treatment. In conclusion, luteolin inhibits angiogenesis and VM formation in gastric cancer through suppressing VEGF secretion dependent on Notch1 expression. Copyright © 2017 Elsevier Inc. All rights reserved.

HAMLET - A protein-lipid complex with broad tumoricidal activity.

PubMed

Ho, James C S; Nadeem, Aftab; Svanborg, Catharina

2017-01-15

HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) is a tumoricidal protein-lipid complex with broad effects against cancer cells of different origin. The therapeutic potential is emphasized by a high degree of specificity for tumor tissue. Here we review early studies of HAMLET, in collaboration with the Orrenius laboratory, and some key features of the subsequent development of the HAMLET project. The early studies focused on the apoptotic response that accompanies death in HAMLET treated tumor cells and the role of mitochondria in this process. In subsequent studies, we have identified a sequence of interactions that starts with the membrane integration of HAMLET and the activation of ion fluxes followed by HAMLET internalization, progressive inhibition of MAPK kinases and GTPases and sorting of HAMLET to different cellular compartments, including the nuclei. Therapeutic efficacy of HAMLET has been demonstrated in animal models of glioblastoma, bladder cancer and intestinal cancer. In clinical studies, HAMLET has been shown to target skin papillomas and bladder cancers. The findings identify HAMLET as a new drug candidate with promising selectivity for cancer cells and a strong therapeutic potential. Copyright © 2016 Elsevier Inc. All rights reserved.

Tests of the relative roles of calcium channels and calcium pumps in controlling gravity-directed development in single spore cells of the fern Ceratopteris richardii

NASA Astrophysics Data System (ADS)

Roux, Stanley; Porterfield, D. Marshall; Haque, Aeraj Ul; Bushart, Thomas

The vector of gravity sets the direction of polarized development of single spore cells of the fern Ceratopteris richardii after light initiates their germination. Gravity also sets the direction of a trans-cell calcium current, which enters the cell along its bottom and exits it from its top. The direction of this current predicts the subsequent direction of spore development, and blocking this current with calcium channel blockers randomizes the direction of subsequent development. Recently the laboratory of D. Marshall Porterfield (Purdue University) developed a microchip device that can measure the direction and magnitude of the trans-spore calcium current in real time. Our laboratory in collaboration with Porterfield's recently found that this current inverts rapidly when the cells are turned upside down and that the magnitude of the current rises and falls with the magnitude of the g-force when these cells are tested in parabolic flight on the DC-9 aircraft. We assume that the gravity-directed entry of calcium into these cells is through calcium channels and its exit is through calcium pumps. Here we report our studies of a calcium pump that is highly expressed in the spores during the period when gravity is setting the direction of the calcium current, and we describe pharmacological tests of the relative importance of calcium pumps in maintaining the calcium current and in controlling the direction of subsequent spore development. We found that inhibitors that block the activity of calcium pumps also greatly depress the trans-cell current, but, surprisingly, have little effect on the ability of gravity to set the direction of spore development. These results, in combination with earlier findings, indicate that the gravity-directed opening of calcium channels along the bottom of spore cells plays a more important role in directing subsequent spore development than the activity of calcium pumps, despite the importance of these pumps in maintaining the trans-cell calcium current. Supported by NASA grants NAG2-1586 and NAG10-295 to S. J. R.

Physiological analysis of yeast cells by flow cytometry during serial-repitching of low-malt beer fermentation.

PubMed

Kobayashi, Michiko; Shimizu, Hiroshi; Shioya, Suteaki

2007-05-01

At the end of beer brewing fermentation, yeast cells are collected and repitched for economical reasons. Although it is generally accepted that the physiological state of inoculated yeast cells affects their subsequent fermentation performance, the effect of serial-repitching on the physiological state of such yeast cells has not been well clarified. In this study, the fermentation performance of yeast cells during serial-repitching was investigated. After multiple repitchings, the specific growth rate and maximum optical density (OD(660)) decreased, and increases in isoamyl alcohol, which causes an undesirable flavor, and residual free amino acid nitrogen (FAN) concentrations were observed. The physiological state of individual cells before inoculation was characterized by flow cytometry using the fluorescent dyes dehydrorhodamine 123 (DHR) and bis-(1,3-dibutylbarbituric acid) trimethine oxonol (OXN). The fluorescence intensities of DHR, an indicator of reactive oxygen species (ROSs), and OXN, which indicates membrane potential, gradually increased as the number of serial-repitching cycles increased. Fluorescence intensity correlated strongly with cell growth. The subsequent fermentation performance can be predicted from this correlation.

Anti-mitotic potential of 7-diethylamino-3(2 Prime -benzoxazolyl)-coumarin in 5-fluorouracil-resistant human gastric cancer cell line SNU620/5-FU

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

Kim, Nam Hyun; Kim, Su-Nam; Oh, Joa Sub

2012-02-24

Highlights: Black-Right-Pointing-Pointer DBC exerts antiproliferative potential against 5FU-resistant human gastric cancer cells. Black-Right-Pointing-Pointer This effect is mediated by destabilization of microtubules and subsequent mitotic arrest. Black-Right-Pointing-Pointer DBC enhances apoptosis via caspase activation and downregulation of antiapoptotic genes. -- Abstract: In this study, we investigate an anti-mitotic potential of the novel synthetic coumarin-based compound, 7-diethylamino-3(2 Prime -benzoxazolyl)-coumarin, in 5-fluorouracil-resistant human gastric cancer cell line SNU-620-5FU and its parental cell SNU-620. It exerts the anti-proliferative effects with similar potencies against both cancer cells, which is mediated by destabilization of microtubules and subsequent mitotic arrest. Furthermore, this compound enhances caspase-dependent apoptotic cell deathmore » via decreased expression of anti-apoptotic genes. Taken together, our data strongly support anti-mitotic potential of 7-diethylamino-3(2 Prime -benzoxazolyl)-coumarin against drug-resistant cancer cells which will prompt us to further develop as a novel microtubule inhibitor for drug-resistant cancer chemotherapy.« less

Proton pump inhibitor chemosensitization in human osteosarcoma: from the bench to the patients’ bed

PubMed Central

2013-01-01

Background Major goals in translational oncology are to reduce systemic toxicity of current anticancer strategies and improve effectiveness. An extremely efficient cancer cell mechanism to avoid and/or reduce the effects of highly cytotoxic drugs is the establishment of an acidic microenvironment, an hallmark of all malignant tumors. The H + −rich milieu that anticancer drugs meet once they get inside the tumor leads to their protonation and neutralization, therefore hindering their access into tumor cells. We have previously shown that proton pump inhibitors (PPI) may efficiently counterattack this tumor advantage leading to a consistent chemosensitization of tumors. In this study, we investigated the effects of PPI in chemosensitizing osteosarcoma. Method MG-63 and Saos-2 cell lines were used as human osteosarcoma models. Cell proliferation after pretreatment with PPI and subsequent treatment with cisplatin was evaluated by using erythrosin B dye vital staining. Tumour growth was evaluated in xenograft treated with cisplatin after PPI pretreatment. Subsequently, a multi-centre historically controlled trial, was performed to evaluate the activity of a pre-treatment administration of PPIs as chemosensitizers during neoadjuvant chemotherapy based on methotrexate, cisplatin, and adriamycin. Results Preclinical experiments showed that PPI sensitize both human osteosarcoma cell lines and xenografts to cisplatin. A clinical study subsequently showed that pretreatment with PPI drug esomeprazole leads to an increase in the local effect of chemotherapy, as expressed by percentage of tumor necrosis. This was particularly evident in chondroblastic osteosarcoma, an histological subtype that normally shows a poor histological response. Notably, no significant increase in toxicity was recorded in PPI treated patients. Conclusion This study provides the first evidence that PPI may be beneficially added to standard regimens in combination to conventional chemotherapy. PMID:24156349

Proton pump inhibitor chemosensitization in human osteosarcoma: from the bench to the patients' bed.

PubMed

Ferrari, Stefano; Perut, Francesca; Fagioli, Franca; Brach Del Prever, Adalberto; Meazza, Cristina; Parafioriti, Antonina; Picci, Piero; Gambarotti, Marco; Avnet, Sofia; Baldini, Nicola; Fais, Stefano

2013-10-24

Major goals in translational oncology are to reduce systemic toxicity of current anticancer strategies and improve effectiveness. An extremely efficient cancer cell mechanism to avoid and/or reduce the effects of highly cytotoxic drugs is the establishment of an acidic microenvironment, an hallmark of all malignant tumors. The H +-rich milieu that anticancer drugs meet once they get inside the tumor leads to their protonation and neutralization, therefore hindering their access into tumor cells. We have previously shown that proton pump inhibitors (PPI) may efficiently counterattack this tumor advantage leading to a consistent chemosensitization of tumors. In this study, we investigated the effects of PPI in chemosensitizing osteosarcoma. MG-63 and Saos-2 cell lines were used as human osteosarcoma models. Cell proliferation after pretreatment with PPI and subsequent treatment with cisplatin was evaluated by using erythrosin B dye vital staining. Tumour growth was evaluated in xenograft treated with cisplatin after PPI pretreatment. Subsequently, a multi-centre historically controlled trial, was performed to evaluate the activity of a pre-treatment administration of PPIs as chemosensitizers during neoadjuvant chemotherapy based on methotrexate, cisplatin, and adriamycin. Preclinical experiments showed that PPI sensitize both human osteosarcoma cell lines and xenografts to cisplatin. A clinical study subsequently showed that pretreatment with PPI drug esomeprazole leads to an increase in the local effect of chemotherapy, as expressed by percentage of tumor necrosis. This was particularly evident in chondroblastic osteosarcoma, an histological subtype that normally shows a poor histological response. Notably, no significant increase in toxicity was recorded in PPI treated patients. This study provides the first evidence that PPI may be beneficially added to standard regimens in combination to conventional chemotherapy.

High hydrostatic pressure-induced cell death in human chondrocytes and chondrosarcoma cells.

PubMed

Naal, Florian-Dominique; Mengele, Karin; Schauwecker, Johannes; Gollwitzer, Hans; Gerdesmeyer, Ludger; Reuning, Ute; Mittelmeier, Wolfram; Gradinger, Reiner; Schmitt, Manfred; Diehl, Peter

2005-01-01

In orthopedic surgery, sterilization of bone used for reconstruction of osteoarticular defects caused by malignant tumors is carried out in different ways. At present, to devitalize tumor-bearing osteochondral segments, extracorporal irradiation or autoclaving is mainly used, although both methods have substantial disadvantages, e.g. loss of biomechanical and/or biological integrity of the bone and destabilization of the articular surface. In this regard, high hydrostatic pressure (HHP) treatment of bone is a new, advancing technology, now being used in preclinical testing to inactivate tumor cells. To find out if this technique is also suited for extracorporal inactivation of chondrocytes and chondral tumor cells, the effect of HHP on cell viability and morphology of human chondrocytes / chondrosarcoma cells was investigated in the present study. SW1353 chondrosarcoma cells and chondrocytes were subjected to HHP in the range of 50 to 350 MPa (10 min, 37 degrees C) and, subsequently, cell viability and cell morphology assessed. After exposure at 350 MPa, all HHP-treated chondral cells showed explicit morphological changes, evident by membrane ruffling and bleb formation; chondrosarcoma cells treated this way were irreversibly damaged and not alive. We anticipate that, in orthopedic surgery, HHP eventually can serve as a novel, promising technical approach for cell inactivation (including tumor cells) and allow subsequent reimplantation of the osteoarticular autograft.

Method of freezing living cells and tissues with improved subsequent survival

DOEpatents

Senkan, Selim M.; Hirsch, Gerald P.

1980-01-01

This invention relates to an improved method for freezing red blood cells, ther living cells, or tissues with improved subsequent survival, wherein constant-volume freezing is utilized that results in significantly improved survival compared with constant-pressure freezing; optimization is attainable through the use of different vessel geometries, cooling baths and warming baths, and sample concentrations.

Effect of acid tolerance response (ATR) on attachment of Listeria monocytogenes Scott A to stainless steel under extended exposure to acid or/and salt stress and resistance of sessile cells to subsequent strong acid challenge.

PubMed

Chorianopoulos, Nikos; Giaouris, Efstathios; Grigoraki, Ioanna; Skandamis, Panagiotis; Nychas, George-John

2011-02-28

The aim of this study was to investigate the potential effect of adaptive stationary phase acid tolerance response (ATR) of Listeria monocytogenes Scott A cells on their attachment to stainless steel (SS) under low pH or/and high salt conditions and on the subsequent resistance of sessile cells to strong acid challenge. Nonadapted or acid-adapted stationary-phase L. monocytogenes cells were used to inoculate (ca. 10⁸ CFU/ml) Brain Heart (BH) broth (pH 7.4, 0.5% w/v NaCl) in test tubes containing vertically placed SS coupons (used as abiotic substrates for bacterial attachment). Incubation was carried out at 16 °C for up to 15 days, without any nutrient refreshment. L. monocytogenes cells, prepared as described above, were also exposed to low pH (4.5; adjusted with HCl) or/and high salt (5.5% w/v NaCl) stresses, during attachment. On the 5th, 10th and 15th day of incubation, cells attached to SS coupons were detached (through bead vortexing) and enumerated (by agar plating). Results revealed that ATR significantly (p<0.05) affected bacterial attachment, when the latter took place under moderate acidic conditions (pH 4.5, 0.5 or 5.5% w/v NaCl), with the acid-adapted cells adhering slightly more than the nonadapted ones. Regardless of acidity/salinity conditions during attachment, ATR also enhanced the resistance of sessile cells to subsequent lethal acid challenge (exposure to pH 2 for 6 min; pH adjusted with either hydrochloric or lactic acid). The trend observed with viable count data agreed well with conductance measurements, used to indirectly quantify remaining attached bacteria (following the strong acid challenge) via their metabolic activity. To sum, this study demonstrates that acid adaptation of L. monocytogenes cells during their planktonic growth enhances their subsequent attachment to SS under extended exposure (at 16 °C for up to 15 days) to mild acidic conditions (pH 4.5), while it also improves the resistance of sessile cells to extreme acid treatment (pH 2). Therefore, the ATR of bacterial cells should be carefully considered when applying acidic decontamination strategies to eradicate L. monocytogenes attached to food processing equipment. Copyright © 2011 Elsevier B.V. All rights reserved.

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.

ADOPTIVE-CELL-TRANSFER THERAPY FOR THE TREATMENT OF PATIENTS WITH CANCER

PubMed Central

Dudley, Mark E.; Rosenberg, Steven A.

2008-01-01

Adoptive immunotherapy — the isolation of antigen-specific cells, their ex vivo expansion and activation, and subsequent autologous administration — is a promising approach to inducing antitumour immune responses. The molecular identification of tumour antigens and the ability to monitor the persistence and transport of transferred cells has provided new insights into the mechanisms of tumour immunotherapy. Recent studies have shown the effectiveness of cell-transfer therapies for the treatment of patients with selected metastatic cancers. These studies provide a blueprint for the wider application of adoptive-cell-transfer therapy, and emphasize the requirement for in vivo persistence of the cells for therapeutic efficacy. PMID:12951585

Human platelet lysate successfully promotes proliferation and subsequent chondrogenic differentiation of adipose-derived stem cells: a comparison with articular chondrocytes.

PubMed

Hildner, F; Eder, M J; Hofer, K; Aberl, J; Redl, H; van Griensven, M; Gabriel, C; Peterbauer-Scherb, A

2015-07-01

Fetal calf serum (FCS) bears a potential risk for carrying diseases and eliciting immune reactions. Nevertheless, it still represents the gold standard as medium supplement in cell culture. In the present study, human platelet lysate (PL) was tested as an alternative to FCS for the expansion and subsequent chondrogenic differentiation of human adipose-derived stem cells (ASCs). ASCs were expanded with 10% FCS (group F) or 5% PL (group P). Subsequently, three-dimensional (3D) micromass pellets were created and cultured for 5 weeks in chondrogenic differentiation medium. Additionally, the de- and redifferentiation potential of human articular chondrocytes (HACs) was evaluated and compared to ASCs. Both HACs and ASCs cultured with PL showed strongly enhanced proliferation rates. Redifferentiation of HACs was possible for cells expanded up to 3.3 population doublings (PD). At this stage, PL-expanded HACs demonstrated better redifferentiation potential than FCS-expanded cells. ASCs could also be differentiated following extended passaging. Glycosaminoglycan (GAG) quantification and qRT-PCR of 10 cartilage related markers demonstrated a tendency for increased chondrogenic differentiation of PL-expanded ASCs compared to cells expanded with FCS. Histologically, collagen type II but also collagen type X was mainly present in group P. The present study demonstrates that PL strongly induces proliferation of ASCs, while the chondrogenic differentiation potential is retained. HACs also showed enhanced proliferation and even better redifferentiation when previously expanded with PL. This suggests that PL is superior to FCS as a supplement for the expansion of ASCs and HACs, particularly with regard to chondrogenic (re)differentiation. Copyright © 2013 John Wiley & Sons, Ltd.

Modulation of Dendritic Cell Activation and Subsequent Th1 Cell Polarization by Lidocaine

PubMed Central

Chung, Yeonseok

2015-01-01

Dendritic cells play an essential role in bridging innate and adaptive immunity by recognizing cellular stress including pathogen- and damage-associated molecular patterns and by shaping the types of antigen-specific T cell immunity. Although lidocaine is widely used in clinical settings that trigger cellular stress, it remains unclear whether such treatment impacts the activation of innate immune cells and subsequent differentiation of T cells. Here we showed that lidocaine inhibited the production of IL–6, TNFα and IL–12 from dendritic cells in response to toll-like receptor ligands including lipopolysaccharide, poly(I:C) and R837 in a dose-dependent manner. Notably, the differentiation of Th1 cells was significantly suppressed by the addition of lidocaine while the same treatment had little effect on the differentiation of Th17, Th2 and regulatory T cells in vitro. Moreover, lidocaine suppressed the ovalbumin-specific Th1 cell responses in vivo induced by the adoptive transfer of ovalbumin-pulsed dendritic cells. These results demonstrate that lidocaine inhibits the activation of dendritic cells in response to toll-like receptor signals and subsequently suppresses the differentiation of Th1 cell responses. PMID:26445366

Optimized depletion of chimeric antigen receptor T cells in murine xenograft models of human acute myeloid leukemia

PubMed Central

Kenderian, Saad S.; Shen, Feng; Ruella, Marco; Shestova, Olga; Kozlowski, Miroslaw; Li, Yong; Schrank-Hacker, April; Morrissette, Jennifer J. D.; Carroll, Martin; June, Carl H.; Grupp, Stephan A.; Gill, Saar

2017-01-01

We and others previously reported potent antileukemia efficacy of CD123-redirected chimeric antigen receptor (CAR) T cells in preclinical human acute myeloid leukemia (AML) models at the cost of severe hematologic toxicity. This observation raises concern for potential myeloablation in patients with AML treated with CD123-redirected CAR T cells and mandates novel approaches for toxicity mitigation. We hypothesized that CAR T-cell depletion with optimal timing after AML eradication would preserve leukemia remission and allow subsequent hematopoietic stem cell transplantation. To test this hypothesis, we compared 3 CAR T-cell termination strategies: (1) transiently active anti-CD123 messenger RNA–electroporated CART (RNA-CART123); (2) T-cell ablation with alemtuzumab after treatment with lentivirally transduced anti–CD123-4-1BB-CD3ζ T cells (CART123); and (3) T-cell ablation with rituximab after treatment with CD20-coexpressing CART123 (CART123-CD20). All approaches led to rapid leukemia elimination in murine xenograft models of human AML. Subsequent antibody-mediated depletion of CART123 or CART123-CD20 did not impair leukemia remission. Time-course studies demonstrated that durable leukemia remission required CAR T-cell persistence for 4 weeks prior to ablation. Upon CAR T-cell termination, we further demonstrated successful hematopoietic engraftment with a normal human donor to model allogeneic stem cell rescue. Results from these studies will facilitate development of T-cell depletion strategies to augment the feasibility of CAR T-cell therapy for patients with AML. PMID:28246194

The JPL space photovoltaic program. [energy efficient so1 silicon solar cells for space applications

NASA Technical Reports Server (NTRS)

Scott-Monck, J. A.

1979-01-01

The development of energy efficient solar cells for space applications is discussed. The electrical performance of solar cells as a function of temperature and solar intensity and the influence of radiation and subsequent thermal annealing on the electrical behavior of cells are among the factors studied. Progress in GaAs solar cell development is reported with emphasis on improvement of output power and radiation resistance to demonstrate a solar cell array to meet the specific power and stability requirements of solar power satellites.

Flow-Mediated Stem Cell Labeling with Superparamagnetic Iron Oxide Nanoparticle Clusters

PubMed Central

Shkumatov, Artem; Lai, Mei-Hsiu; Smith, Cartney E.; Rich, Max; Kong, Hyunjoon

2013-01-01

This study presents a strategy to enhance the uptake of superparamagnetic iron oxide nanoparticle (SPIO) clusters by manipulating the cellular mechanical environment. Specifically, stem cells exposed to an orbital flow ingested almost two-fold greater amount of SPIO clusters than those cultured statically. Improvements in MR contrast were subsequently achieved for labeled cells in collagen gels and a mouse model. Overall, this strategy will serve to improve the efficiency of cell tracking and therapies. PMID:24033276

Study of living single cells in culture: automated recognition of cell behavior.

PubMed

Bodin, P; Papin, S; Meyer, C; Travo, P

1988-07-01

An automated system capable of analyzing the behavior, in real time, of single living cells in culture, in a noninvasive and nondestructive way, has been developed. A large number of cell positions in single culture dishes were recorded using a computer controlled, robotized microscope. During subsequent observations, binary images obtained from video image analysis of the microscope visual field allowed the identification of the recorded cells. These cells could be revisited automatically every few minutes. Long-term studies of the behavior of cells make possible the analysis of cellular locomotary and mitotic activities as well as determination of cell shape (chosen from a defined library) for several hours or days in a fully automated way with observations spaced up to 30 minutes. Short-term studies of the behavior of cells permit the study, in a semiautomatic way, of acute effects of drugs (5 to 15 minutes) on changes of surface area and length of cells.

Oxidative stress-induced necrotic cell death via mitochondira-dependent burst of reactive oxygen species.

PubMed

Choi, Kyungsun; Kim, Jinho; Kim, Gyung W; Choi, Chulhee

2009-11-01

Oxidative stress is deeply involved in various brain diseases, including neurodegenerative diseases, stroke, and ischemia/reperfusion injury. Mitochondria are thought to be the target and source of oxidative stress. We investigated the role of mitochondria in oxidative stress-induced necrotic neuronal cell death in a neuroblastoma cell line and a mouse model of middle cerebral artery occlusion. The exogenous administration of hydrogen peroxide was used to study the role of oxidative stress on neuronal cell survival and mitochondrial function in vitro. Hydrogen peroxide induced non-apoptotic neuronal cell death in a c-Jun N-terminal kinase- and poly(ADP-ribosyl) polymerase-dependent manner. Unexpectedly, hydrogen peroxide treatment induced transient hyperpolarization of the mitochondrial membrane potential and a subsequent delayed burst of endogenous reactive oxygen species (ROS). The inhibition of mitochondrial hyperpolarization by diphenylene iodonium or rotenone, potent inhibitors of mitochondrial respiratory chain complex I, resulted in reduced ROS production and subsequent neuronal cell death in vitro and in vivo. The inhibition of mitochondrial hyperpolarization can protect neuronal cells from oxidative stress-induced necrotic cell death, suggesting a novel method of therapeutic intervention in oxidative stress-induced neurological disease.

The impact of ischemia-reperfusion injuries on skin resident murine dendritic cells.

PubMed

Goh, Chi Ching; Evrard, Maximilien; Chong, Shu Zhen; Tan, Yingrou; Tan, Leonard De Li; Teng, Karen Wei Weng; Weninger, Wolfgang; Becker, David Laurence; Tey, Hong Liang; Newell, Evan William; Liu, Bin; Ng, Lai Guan

2018-06-01

Pressure ulcers are a chronic problem for patients or the elderly who require extended periods of bed rest. The formation of ulcers is due to repeated cycles of ischemia-reperfusion (IR), which initiates an inflammatory response. Advanced ulcers disrupt the skin barrier, resulting in further complications. To date, the immunological aspect of skin IR has been understudied, partly due to the complexity of the skin immune cells. Through a combination of mass cytometry, confocal imaging and intravital multiphoton imaging, this study establishes a workflow for multidimensionality single cell analysis of skin myeloid cell responses in the context of IR injury with high spatiotemporal resolution. The data generated has provided us with previously uncharacterized insights into the distinct cellular behavior of resident dendritic cells (DCs) and recruited neutrophils post IR. Of interest, we observed a drop in DDC numbers in the IR region, which was subsequently replenished 48h post IR. More importantly, in these cells, we observe an attenuated response to repeated injuries, which may have implications in the subsequent wound healing process. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of an electro-responsive platform for the controlled transfection of mammalian cells

NASA Astrophysics Data System (ADS)

Hook, Andrew L.; Thissen, Helmut W.; Hayes, Jason P.; Voelcker, Nicolas H.

2005-02-01

The recent development of living microarrays as novel tools for the analysis of gene expression in an in-situ environment promises to unravel gene function within living organisms. In order to significantly enhance microarray performance, we are working towards electro-responsive DNA transfection chips. This study focuses on the control of DNA adsorption and desorption by appropriate surface modification of highly doped p++ silicon. Silicon was modified by plasma polymerisation of allylamine (ALAPP), a non-toxic surface that sustains cell growth. Subsequent high surface density grafting of poly(ethylene oxide) formed a layer resistant to biomolecule adsorption and cell attachment. Spatially controlled excimer laser ablation of the surface produced micron resolution patterns of re-exposed plasma polymer whilst the rest of the surface remained non-fouling. We observed electro-stimulated preferential adsorption of DNA to the ALAPP surface and subsequent desorption by the application of a negative bias. Cell culture experiments with HEK 293 cells demonstrated efficient and controlled transfection of cells using the expression of green fluorescent protein as a reporter. Thus, these chemically patterned surfaces are promising platforms for use as living microarrays.

Paraneoplastic cerebellar degeneration and lambert-eaton myasthenia in a patient with merkel cell carcinoma and voltage-gated calcium channel antibodies.

PubMed

Pavolucci, Lucia; Giannini, Giulia; Giannoccaro, Maria Pia; Foschini, Maria Pia; Lang, Bethan; Avoni, Patrizia; Tinuper, Paolo; Vincent, Angela; Liguori, Rocco

2017-11-01

Merkel cell carcinoma is a rare cutaneous, aggressive tumor. Although it shares many neuroendocrine features with small cell lung carcinoma, it has only occasionally been reported with paraneoplastic neurological syndromes. A healthy 67-year-old man developed acute ataxia, vertigo, and nausea. Subsequently he also developed dysarthria, diplopia, xerostomia, fatigability and progressive anorexia. He underwent a full diagnostic workup and was found to have a high titer of voltage-gated calcium channel antibodies in serum and cerebrospinal fluid, neurophysiological findings compatible with Lambert-Eaton myasthenia and neurological signs compatible with cerebellar degeneration. A positron emission tomography study revealed a hypermetabolic lesion in the axilla, subsequently biopsied and consistent with Merkel cell carcinoma. In most previous reports, neurological symptoms preceded the Merkel cell carcinoma diagnosis, and the primary localization was in lymph nodes. This tumor should be considered in patients with paraneoplastic syndrome, and particularly Lambert-Eaton myasthenia after exclusion of small cell lung carcinoma. Muscle Nerve 56: 998-1000, 2017. © 2016 Wiley Periodicals, Inc.

Liposomal CpG-ODN: An in vitro and in vivo study on macrophage subtypes responses, biodistribution and subsequent therapeutic efficacy in mice models of cancers.

PubMed

Nikoofal-Sahlabadi, Sara; Matbou Riahi, Maryam; Sadri, Kayvan; Badiee, Ali; Nikpoor, Amin Reza; Jaafari, Mahmoud Reza

2018-07-01

CpG oligodeoxynucleotides (CpG-ODN), a common immune stimulator and vaccine adjuvant, was reported to switch Tumor Associated Macrophages (TAMs) from M2 to M1 phenotype inducing anti-tumor responses. Liposomes are of the successfully applied carriers for CpG-ODN. The aim of present study was design and preparation of a liposomal formulation containing phosphodiester CpG-ODN, evaluation of its effect on macrophages responses, and subsequent antitumor responses in mice. Liposomal formulations containing phosphodiester CpG-ODN or non-CpG-ODN were prepared and characterized. MTT reduction assay in four different cell lines, uptake, arginase and iNOS activity evaluation in macrophage cell lines, biodistribution study and therapeutic anti-tumor effects of formulations in mice bearing C26 colon carcinoma or B16F0 melanoma were carried out. The size of liposomes containing CpG-ODN was ~200 nm with the encapsulation efficiency of 33%. The iNOS activity assay showed high nitric oxide (NO) level in M2 phenotype of macrophage cell lines treated by liposomes containing CpG-ODN. In mice which received liposomes containing CpG-ODN as a monotherapy, maximum tumor growth delay with remarkable survival improvement was observed compared to control groups. Biodistribution study showed the accumulation of liposomal formulation in tumor micro-environment. In conclusion, considerable anti-tumor responses observed by liposomes containing CpG-ODN was due to enhanced delivery of CpG-ODN to immune cells and subsequent initiation of anti-tumoral immune responses. Copyright © 2018 Elsevier B.V. All rights reserved.

T-cell activation is enhanced by targeting IL-10 cytokine production in toll-like receptor-stimulated macrophages

PubMed Central

Walk, Ryan M; Elliott, Steven T; Blanco, Felix C; Snyder, Jason A; Jacobi, Ashley M; Rose, Scott D; Behlke, Mark A; Salem, Aliasger K; Vukmanovic, Stanislav; Sandler, Anthony D

2012-01-01

Toll-like receptor (TLR) agonists represent potentially useful cancer vaccine adjuvants in their ability to stimulate antigen-presenting cells (APCs) and subsequently amplify the cytotoxic T-cell response. The purpose of this study was to characterize APC responses to TLR activation and to determine the subsequent effect on lymphocyte activation. We exposed murine primary bone marrow-derived macrophages to increasing concentrations of agonists to TLRs 2, 3, 4, and 9. This resulted in a dose-dependent increase in production of not only tumor necrosis factor–alpha (TNF-α), a surrogate marker of the proinflammatory response, but also interleukin 10 (IL-10), a well-described inhibitory cytokine. Importantly, IL-10 secretion was not induced by low concentrations of TLR agonists that readily produced TNF-α. We subsequently stimulated lymphocytes with anti-CD3 antibody in the presence of media from macrophages activated with higher doses of TLR agonists and observed suppression of interferon gamma release. Use of both IL-10 knockout macrophages and IL-10 small-interfering RNA (siRNA) ablated this suppressive effect. Finally, IL-10 siRNA was successfully used to suppress CpG-induced IL-10 production in vivo. We conclude that TLR-mediated APC stimulation can induce a paradoxical inhibitory effect on T-cell activation mediated by IL-10. PMID:27471682

SOX10-positive cells emerge in the rat pituitary gland during late embryogenesis and start to express S100β.

PubMed

Ueharu, Hiroki; Yoshida, Saishu; Kanno, Naoko; Horiguchi, Kotaro; Nishimura, Naoto; Kato, Takako; Kato, Yukio

2018-04-01

In the pituitary gland, S100β-positive cells localize in the neurohypophysis and adenohypophysis but the lineage of the two groups remains obscure. S100β is often observed in many neural crest-derived cell types. Therefore, in this study, we investigate the origin of pituitary S100β-positive cells by immunohistochemistry for SOX10, a potent neural crest cell marker, using S100β-green fluorescence protein-transgenic rats. On embryonic day 21.5, a SOX10-positive cell population, which was also positive for the stem/progenitor cell marker SOX2, emerged in the pituitary stalk and posterior lobe and subsequently expanded to create a rostral-caudal gradient on postnatal day 3 (P3). Thereafter, SOX10-positive cells appeared in the intermediate lobe by P15, localizing to the boundary facing the posterior lobe, the gap between the lobule structures and the marginal cell layer, a pituitary stem/progenitor cell niche. Subsequently, there was an increase in SOX10/S100β double-positive cells; some of these cells in the gap between the lobule structures showed extended cytoplasm containing F-actin, indicating a feature of migration activity. The proportion of SOX10-positive cells in the postnatal anterior lobe was lower than 0.025% but about half of them co-localized with the pituitary-specific progenitor cell marker PROP1. Collectively, the present study identified that one of the lineages of S100β-positive cells is a SOX10-positive one and that SOX10-positive cells express pituitary stem/progenitor cell marker genes.

Ischemic preconditioning protects against gap junctional uncoupling in cardiac myofibroblasts.

PubMed

Sundset, Rune; Cooper, Marie; Mikalsen, Svein-Ole; Ytrehus, Kirsti

2004-01-01

Ischemic preconditioning increases the heart's tolerance to a subsequent longer ischemic period. The purpose of this study was to investigate the role of gap junction communication in simulated preconditioning in cultured neonatal rat cardiac myofibroblasts. Gap junctional intercellular communication was assessed by Lucifer yellow dye transfer. Preconditioning preserved intercellular coupling after prolonged ischemia. An initial reduction in coupling in response to the preconditioning stimulus was also observed. This may protect neighboring cells from damaging substances produced during subsequent regional ischemia in vivo, and may preserve gap junctional communication required for enhanced functional recovery during subsequent reperfusion.

Clonal evolution through loss of chromosomes and subsequent polyploidization in chondrosarcoma.

PubMed

Olsson, Linda; Paulsson, Kajsa; Bovée, Judith V M G; Nord, Karolin H

2011-01-01

Near-haploid chromosome numbers have been found in less than 1% of cytogenetically reported tumors, but seem to be more common in certain neoplasms including the malignant cartilage-producing tumor chondrosarcoma. By a literature survey of published karyotypes from chondrosarcomas we could confirm that loss of chromosomes resulting in hyperhaploid-hypodiploid cells is common and that these cells may polyploidize. Sixteen chondrosarcomas were investigated by single nucleotide polymorphism (SNP) array and the majority displayed SNP patterns indicative of a hyperhaploid-hypodiploid origin, with or without subsequent polyploidization. Except for chromosomes 5, 7, 19, 20 and 21, autosomal loss of heterozygosity was commonly found, resulting from chromosome loss and subsequent duplication of monosomic chromosomes giving rise to uniparental disomy. Additional gains, losses and rearrangements of genetic material, and even repeated rounds of polyploidization, may affect chondrosarcoma cells resulting in highly complex karyotypes. Loss of chromosomes and subsequent polyploidization was not restricted to a particular chondrosarcoma subtype and, although commonly found in chondrosarcoma, binucleated cells did not seem to be involved in these events.

A dynamic dual role of IL-2 signaling in the two-step differentiation process of adaptive regulatory T cells.

PubMed

Guo, Zhiyong; Khattar, Mithun; Schroder, Paul M; Miyahara, Yoshihiro; Wang, Guohua; He, Xiaoshung; Chen, Wenhao; Stepkowski, Stanislaw M

2013-04-01

The molecular mechanism of the extrathymic generation of adaptive, or inducible, CD4(+)Foxp3(+) regulatory T cells (iTregs) remains incompletely defined. We show that exposure of splenic CD4(+)CD25(+)Foxp3(-) cells to IL-2, but not other common γ-chain cytokines, resulted in Stat5 phosphorylation and induced Foxp3 expression in ∼10% of the cells. Thus, IL-2/Stat5 signaling may be critical for Foxp3 induction in peripheral CD4(+)CD25(+)Foxp3(-) iTreg precursors. In this study, to further define the role of IL-2 in the formation of iTreg precursors as well as their subsequent Foxp3 expression, we designed a two-step iTreg differentiation model. During the initial "conditioning" step, CD4(+)CD25(-)Foxp3(-) naive T cells were activated by TCR stimulation. Inhibition of IL-2 signaling via Jak3-Stat5 was required during this step to generate CD4(+)CD25(+)Foxp3(-) cells containing iTreg precursors. During the subsequent Foxp3-induction step driven by cytokines, IL-2 was the most potent cytokine to induce Foxp3 expression in these iTreg precursors. This two-step method generated a large number of iTregs with relatively stable expression of Foxp3, which were able to prevent CD4(+)CD45RB(high) cell-mediated colitis in Rag1(-/-) mice. In consideration of this information, whereas initial inhibition of IL-2 signaling upon T cell priming generates iTreg precursors, subsequent activation of IL-2 signaling in these precursors induces the expression of Foxp3. These findings advance the understanding of iTreg differentiation and may facilitate the therapeutic use of iTregs in immune disorders.

Isoflurane preconditioning protects neurons from male and female mice against oxygen and glucose deprivation and is modulated by estradiol only in neurons from female mice.

PubMed

Johnsen, D; Murphy, S J

2011-12-29

The volatile anesthetic, isoflurane, can protect the brain if administered before an insult such as an ischemic stroke. However, this protective "preconditioning" response to isoflurane is specific to males, with females showing an increase in brain damage following isoflurane preconditioning and subsequent focal cerebral ischemia. Innate cell sex is emerging as an important player in neuronal cell death, but its role in the sexually dimorphic response to isoflurane preconditioning has not been investigated. We used an in vitro model of isoflurane preconditioning and ischemia (oxygen and glucose deprivation, OGD) to test the hypotheses that innate cell sex dictates the response to isoflurane preconditioning and that 17β-estradiol attenuates any protective effect from isoflurane preconditioning in neurons via nuclear estrogen receptors. Sex-segregated neuron cultures derived from postnatal day 0-1 mice were exposed to either 0% or 3% isoflurane preconditioning for 1 h. In separate experiments, 17β-estradiol and the non-selective estrogen receptor antagonist ICI 182,780 were added 24 h before preconditioning and then removed at the end of the preconditioning period. Twenty-three hours after preconditioning, all cultures underwent 2 h of OGD. Twenty-four hours following OGD, cell viability was quantified using calcein-AM fluorescence. We observed that isoflurane preconditioning increased cell survival following subsequent OGD regardless of innate cell sex, but that the presence of 17β-estradiol before and during isoflurane preconditioning attenuated this protection only in female neurons independent of nuclear estrogen receptors. We also found that independent of preconditioning treatment, female neurons were less sensitive to OGD compared with male neurons and that transient treatment with 17β-estradiol protected both male and female neurons from subsequent OGD. More studies are needed to determine how cell type, cell sex, and sex steroids like 17β-estradiol may impact on anesthetic preconditioning and subsequent ischemic outcomes in the brain. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

Identification of Novel Human Breast Carcinoma (MDA-MB-231) Cell Growth Modulators from a Carbohydrate-Based Diversity Oriented Synthesis Library.

PubMed

Lenci, Elena; Innocenti, Riccardo; Biagioni, Alessio; Menchi, Gloria; Bianchini, Francesca; Trabocchi, Andrea

2016-10-20

The application of a cell-based growth inhibition on a library of skeletally different glycomimetics allowed for the selection of a hexahydro-2 H -furo[3,2- b ][1,4]oxazine compound as candidate inhibitors of MDA-MB-231 cell growth. Subsequent synthesis of analogue compounds and preliminary biological studies validated the selection of a valuable hit compound with a novel polyhydroxylated structure for the modulation of the breast carcinoma cell cycle mechanism.

Intranasal Live Influenza Vaccine Priming Elicits Localized B Cell Responses in Mediastinal Lymph Nodes.

PubMed

Jegaskanda, Sinthujan; Mason, Rosemarie D; Andrews, Sarah F; Wheatley, Adam K; Zhang, Ruijun; Reynoso, Glennys V; Ambrozak, David R; Santos, Celia P; Luke, Catherine J; Matsuoka, Yumiko; Brenchley, Jason M; Hickman, Heather D; Talaat, Kawsar R; Permar, Sallie R; Liao, Hua-Xin; Yewdell, Jonathan W; Koup, Richard A; Roederer, Mario; McDermott, Adrian B; Subbarao, Kanta

2018-05-01

Pandemic live attenuated influenza vaccines (pLAIV) prime subjects for a robust neutralizing antibody response upon subsequent administration of a pandemic inactivated subunit vaccine (pISV). However, a difference was not detected in H5-specific memory B cells in the peripheral blood between pLAIV-primed and unprimed subjects prior to pISV boost. To investigate the mechanism underlying pLAIV priming, we vaccinated groups of 12 African green monkeys (AGMs) with H5N1 pISV or pLAIV alone or H5N1 pLAIV followed by pISV and examined immunity systemically and in local draining lymph nodes (LN). The AGM model recapitulated the serologic observations from clinical studies. Interestingly, H5N1 pLAIV induced robust germinal center B cell responses in the mediastinal LN (MLN). Subsequent boosting with H5N1 pISV drove increases in H5-specific B cells in the axillary LN, spleen, and circulation in H5N1 pLAIV-primed animals. Thus, H5N1 pLAIV primes localized B cell responses in the MLN that are recalled systemically following pISV boost. These data provide mechanistic insights for the generation of robust humoral responses via prime-boost vaccination. IMPORTANCE We have previously shown that pandemic live attenuated influenza vaccines (pLAIV) prime for a rapid and robust antibody response on subsequent administration of inactivated subunit vaccine (pISV). This is observed even in individuals who had undetectable antibody (Ab) responses following the initial vaccination. To define the mechanistic basis of pLAIV priming, we turned to a nonhuman primate model and performed a detailed analysis of B cell responses in systemic and local lymphoid tissues following prime-boost vaccination with pLAIV and pISV. We show that the nonhuman primate model recapitulates the serologic observations from clinical studies. Further, we found that pLAIVs induced robust germinal center B cell responses in the mediastinal lymph node. Subsequent boosting with pISV in pLAIV-primed animals resulted in detection of B cells in the axillary lymph nodes, spleen, and peripheral blood. We demonstrate that intranasally administered pLAIV elicits a highly localized germinal center B cell response in the mediastinal lymph node that is rapidly recalled following pISV boost into germinal center reactions at numerous distant immune sites. Copyright © 2018 American Society for Microbiology.

Minocycline attenuates colistin-induced neurotoxicity via suppression of apoptosis, mitochondrial dysfunction and oxidative stress

PubMed Central

Dai, Chongshan; Ciccotosto, Giuseppe D.; Cappai, Roberto; Wang, Yang; Tang, Shusheng; Xiao, Xilong; Velkov, Tony

2017-01-01

Background: Neurotoxicity is an adverse effect patients experience during colistin therapy. The development of effective neuroprotective agents that can be co-administered during polymyxin therapy remains a priority area in antimicrobial chemotherapy. The present study investigates the neuroprotective effect of the synergistic tetracycline antibiotic minocycline against colistin-induced neurotoxicity. Methods: The impact of minocycline pretreatment on colistin-induced apoptosis, caspase activation, oxidative stress and mitochondrial dysfunction were investigated using cultured mouse neuroblastoma-2a (N2a) and primary cortical neuronal cells. Results: Colistin-induced neurotoxicity in mouse N2a and primary cortical cells gives rise to the generation of reactive oxygen species (ROS) and subsequent cell death via apoptosis. Pretreatment of the neuronal cells with minocycline at 5, 10 and 20 μM for 2 h prior to colistin (200 μM) exposure (24 h), had an neuroprotective effect by significantly decreasing intracellular ROS production and by upregulating the activities of the anti-ROS enzymes superoxide dismutase and catalase. Minocycline pretreatment also protected the cells from colistin-induced mitochondrial dysfunction, caspase activation and subsequent apoptosis. Immunohistochemical imaging studies revealed colistin accumulates within the dendrite projections and cell body of primary cortical neuronal cells. Conclusions: To our knowledge, this is first study demonstrating the protective effect of minocycline on colistin-induced neurotoxicity by scavenging of ROS and suppression of apoptosis. Our study highlights that co-administration of minocycline kills two birds with one stone: in addition to its synergistic antimicrobial activity, minocycline could potentially ameliorate unwanted neurotoxicity in patients undergoing polymyxin therapy. PMID:28204513

Non-thermal plasma induces mitochondria-mediated apoptotic signaling pathway via ROS generation in HeLa cells.

PubMed

Li, Wei; Yu, K N; Ma, Jie; Shen, Jie; Cheng, Cheng; Zhou, Fangjian; Cai, Zhiming; Han, Wei

2017-11-01

Non-thermal plasma (NTP) has been proposed as a novel therapeutic method for anticancer treatment. Although increasing evidence suggests that NTP selectively induces apoptosis in some types of tumor cells, the molecular mechanisms underlying this phenomenon remain unclear. In this study, we further investigated possible molecular mechanisms for NTP-induced apoptosis of HeLa cells. The results showed that NTP exposure significantly inhibited the growth and viability of HeLa cells. Morphological observation and flow cytometry analysis demonstrated that NTP exposure induced HeLa cell apoptosis. NTP exposure also activated caspase-9 and caspase-3, which subsequently cleaved poly (ADP- ribose) polymerase. Furthermore, NTP exposure suppressed Bcl-2 expression, enhanced Bax expression and translocation to mitochondria, activated mitochondria-mediated apoptotic pathway, followed by the release of cytochrome c. Further studies showed that NTP treatment led to ROS generation, whereas blockade of ROS generation by N-acetyl-l-cysteine (NAC, ROS scavengers) significantly prevented NTP-induced mitochondrial alteration and subsequent apoptosis of HeLa cells via suppressing Bax translocation, cytochrome c and caspase-3 activation. Taken together, our results indicated that NTP exposure induced mitochondria-mediated intrinsic apoptosis of HeLa cells was activated by ROS generation. These findings provide insights to the therapeutic potential and clinical research of NTP as a novel tool in cervical cancer treatment. Copyright © 2017. Published by Elsevier Inc.

PC61 (Anti-CD25) Treatment Inhibits Influenza A Virus-Expanded Regulatory T Cells and Severe Lung Pathology during a Subsequent Heterologous Lymphocytic Choriomeningitis Virus Infection

PubMed Central

Kraft, Anke R. M.; Wlodarczyk, Myriam F.; Kenney, Laurie L.

2013-01-01

Prior immunity to influenza A virus (IAV) in mice changes the outcome to a subsequent lymphocytic choriomeningitis virus (LCMV) infection and can result in severe lung pathology, similar to that observed in patients that died of the 1918 H1N1 pandemic. This pathology is induced by IAV-specific memory CD8+ T cells cross-reactive with LCMV. Here, we discovered that IAV-immune mice have enhanced CD4+ Foxp3+ T-regulatory (Treg) cells in their lungs, leading us to question whether a modulation in the normal balance of Treg and effector T-cell responses also contributes to enhancing lung pathology upon LCMV infection of IAV-immune mice. Treg cell and interleukin-10 (IL-10) levels remained elevated in the lungs and mediastinal lymph nodes (mLNs) throughout the acute LCMV response of IAV-immune mice. PC61 treatment, used to decrease Treg cell levels, did not change LCMV titers but resulted in a surprising decrease in lung pathology upon LCMV infection in IAV-immune but not in naive mice. Associated with this decrease in pathology was a retention of Treg in the mLN and an unexpected partial clonal exhaustion of LCMV-specific CD8+ T-cell responses only in IAV-immune mice. PC61 treatment did not affect cross-reactive memory CD8+ T-cell proliferation. These results suggest that in the absence of IAV-expanded Treg cells and in the presence of cross-reactive memory, the LCMV-specific response was overstimulated and became partially exhausted, resulting in a decreased effector response. These studies suggest that Treg cells generated during past infections can influence the characteristics of effector T-cell responses and immunopathology during subsequent heterologous infections. Thus, in humans with complex infection histories, PC61 treatment may lead to unexpected results. PMID:24049180

Inducible growth mode switches influence Valonia rhizoid differentiation.

PubMed

Elvira, Paul Rommel; Sekida, Satoko; Okuda, Kazuo

2013-02-01

Cell differentiation and cell type commitment are an integral part of plant growth and development. Investigations on how environmental conditions affect the formation of shoots, roots, and rhizoids can help illustrate how plants determine cell fate and overall morphology. In this study, we evaluated the role of substratum and light on rhizoid differentiation in the coenocytic green alga, Valonia aegagropila. Elongating rhizoids displayed varying growth modes and cell shape upon exposure to different substrata and light conditions. It was found that soft substrata and dark incubation promoted rhizoid elongation via tip growth while subsequent exposure to light prevented tip growth and instead induced swelling in the apical region of rhizoids. Swelling was accompanied by the accumulation of protoplasm in the rhizoid tip through expansion of the cell wall and uninhibited cytoplasmic streaming. Subsequent diffuse growth led to the transformation from slender, rod-shaped rhizoids into spherical thallus-like structures that required photosynthesis. Further manipulation of light regimes caused vacillating cell growth redirections. An elongating V. aegagropila rhizoid cell thus appears capable of growth mode switching that is regulated by immediate environmental conditions thereby influencing ultimate cell shape and function. This is the first description of inducible, multiple growth mode shifts in a single intact plant cell that directly impact its differentiation.

Progenitor cell dose determines the pace and completeness of engraftment in a xenograft model for cord blood transplantation

PubMed Central

Liu, Congxiao; Chen, Benny J.; DeOliveira, Divinomar; Sempowski, Gregory D.; Chao, Nelson J.

2010-01-01

Two critical concerns in clinical cord blood transplantation are the initial time to engraftment and the subsequent restoration of immune function. These studies measured the impact of progenitor cell dose on both the pace and strength of hematopoietic reconstitution by transplanting nonobese diabetic/severe combined immunodeficiency/interleukin-2 receptor-gamma–null (NSγ) mice with lineage-depleted aldehyde dehydrogenase-bright CD34+ human cord blood progenitors. The progress of each transplant was monitored over an extended time course by repeatedly analyzing the peripheral blood for human hematopoietic cells. In vivo human hematopoietic development was complete. After long-term transplantation assays (≥ 19 weeks), human T-cell development was documented within multiple tissues in 16 of 32 NSγ mice. Human T-cell differentiation was active within NSγ thymuses, as documented by the presence of CD4+ CD8+ T-cell progenitors as well as T-cell receptor excision circles. It is important to note that although myeloid and B-cell engraftment was detected as early as 4 weeks after transplantation, human T-cell development was exclusively late onset. High progenitor cell doses were associated with a robust human hematopoietic chimerism that accelerated both initial time to engraftment and subsequent T-cell development. At lower progenitor cell doses, the chimerism was weak and the human hematopoietic lineage development was frequently incomplete. PMID:20833978

Defining the Regulation of Telomerase Through Identification of Mammary-Specific Telomerase Interacting Proteins

DTIC Science & Technology

2007-06-01

Pharmacology and Toxicology , Virginia Commonwealth University, Richmond, VA 2002-present Member, Molecular Biology and Genetics Program, Virginia...Studying Telomeres and Telomerase. Zebrafish , 1:349-355. Jones,K.R., L.W.Elmore, L.Povirk, S.E.Holt, and D.A.Gewirtz. 2005. Reciprocal regulation... Zebrafish Blastula Cell Line on Rainbow Trout Stromal Cells and Subsequent Development under Feeder-Free Conditions into a Cell Line, ZEB2J. Zebrafish 5: 49

[THE TECHNOLOGY "CELL BLOCK" IN CYTOLOGICAL PRACTICE].

PubMed

Volchenko, N N; Borisova, O V; Baranova, I B

2015-08-01

The article presents summary information concerning application of "cell block" technology in cytological practice. The possibilities of implementation of various modern techniques (immune cytochemnical analysis. FISH, CISH, polymerase chain reaction) with application of "cell block" method are demonstrated. The original results of study of "cell block" technology made with gelatin, AgarCyto and Shadon Cyoblock set are presented. The diagnostic effectiveness of "cell block" technology and common cytological smear and also immune cytochemical analysis on samples of "cell block" technology and fluid cytology were compared. Actually application of "cell block" technology is necessary for ensuring preservation of cell elements for subsequent immune cytochemical and molecular genetic analysis.

Emergence of cooperativity in a model biofilm

NASA Astrophysics Data System (ADS)

Rotrattanadumrong, Rachapun; Endres, Robert G.

2017-06-01

Evolution to multicellularity from an aggregate of cells involves altruistic cooperation between individual cells, which is in conflict with Darwinian evolution. How cooperation arises and how a cell community resolves such conflicts remains unclear. In this study, we investigated the spontaneous emergence of cell differentiation and the subsequent division of labour in evolving cellular metabolic networks. In spatially extended cell aggregates, our findings reveal that resource limitation can lead to the formation of subpopulations and cooperation of cells, and hence multicellular communities. A specific example of our model can explain the recently observed oscillatory growth in Bacillus subtilis biofilms.

Protein Adsorption and Subsequent Fibroblasts Adhesion on Hydroxyapatite Nanocrystals

NASA Astrophysics Data System (ADS)

Tagaya, Motohiro; Ikoma, Toshiyuki; Takemura, Taro; Hanagata, Nobutaka; Yoshioka, Tomohiko; Tanaka, Junzo

2011-10-01

Quartz crystal microbalance with dissipation (QCM-D) technique was employed for protein adsorption and subsequent fibroblast adhesion on hydroxyapatite (HAp) nanocrystals. The pre-adsorption of three proteins (albumin (BSA) or fibronectin (Fn) or collagen (Col)) and subsequent adsorption of fetal bovine serum (FBS), and the adhesion of fibroblasts on the surface were in situ monitored, and evaluated with the frequency shift (Δf) and dissipation energy shift (ΔD), and the viscoelastic change as ΔD-Δf plot. The Col adsorption showed larger Δf and ΔD values compared with BSA or Fn adsorption, and the subsequent FBS adsorption depended on the pre-adsorbed proteins. The ΔD-Δf plot of the cell adhesion also showed the different behaviour on the surfaces, indicating the process affected by cell-protein interactions. The confocal laser scanning microscope images of adherent cells showed the different morphology and pseudopod on the surfaces. The cells adhered on the surfaces modified with Fn and Col had the uniaxially expanded shape with fibrous pseudopods, while those modified with BSA had round shape. The different cell-protein interaction would cause the arrangement of extracellular matrix and cytoskeleton changes at the interfaces.

Adaptive responses induced by 24S-hydroxycholesterol through liver X receptor pathway reduce 7-ketocholesterol-caused neuronal cell death☆

PubMed Central

Okabe, Akishi; Urano, Yasuomi; Itoh, Sayoko; Suda, Naoto; Kotani, Rina; Nishimura, Yuki; Saito, Yoshiro; Noguchi, Noriko

2013-01-01

Lipid peroxidation products have been known to induce cellular adaptive responses and enhance tolerance against subsequent oxidative stress through up-regulation of antioxidant compounds and enzymes. 24S-hydroxycholesterol (24SOHC) which is endogenously produced oxysterol in the brain plays an important role in maintaining brain cholesterol homeostasis. In this study, we evaluated adaptive responses induced by brain-specific oxysterol 24SOHC in human neuroblastoma SH-SY5Y cells. Cells treated with 24SOHC at sub-lethal concentrations showed significant reduction in cell death induced by subsequent treatment with 7-ketocholesterol (7KC) in both undifferentiated and retinoic acid-differentiated SH-SY5Y cells. These adaptive responses were also induced by other oxysterols such as 25-hydroxycholesterol and 27-hydroxycholesterol which are known to be ligands of liver X receptor (LXR). Co-treatment of 24SOHC with 9-cis retinoic acid, a retinoid X receptor ligand, enhanced the adaptive responses. Knockdown of LXRβ by siRNA diminished the adaptive responses induced by 24SOHC almost completely. The treatment with 24SOHC induced the expression of LXR target genes, such as ATP-binding cassette transporter A1 (ABCA1) and G1 (ABCG1). The 24SOHC-induced adaptive responses were significantly attenuated by siRNA for ABCG1 but not by siRNA for ABCA1. Taken together, these results strongly suggest that 24SOHC at sub-lethal concentrations induces adaptive responses via transcriptional activation of LXR signaling pathway, thereby protecting neuronal cells from subsequent 7KC-induced cytotoxicity. PMID:24371802

Pre-existing central nervous system lesions negate cytokine requirements for regional experimental autoimmune encephalomyelitis development.

PubMed

Li, Xin; Lees, Jason R

2013-03-01

In region-specific forms of experimental autoimmune encephalomyelitis (EAE), lesion initiation is regulated by T-cell-produced interferon-γ (IFN-γ) resulting in spinal cord disease in the presence of IFN-γ and cerebellar disease in the absence of IFN-γ. Although this role for IFN-γ in regional disease initiation is well defined, little is known about the consequences of previous tissue inflammation on subsequent regional disease, information vital to the development of therapeutics in established disease states. This study addressed the hypothesis that previous establishment of regional EAE would determine subsequent tissue localization of new T-cell invasion and associated symptoms regardless of the presence or absence of IFN-γ production. Serial transfer of optimal or suboptimal doses of encephalitogenic IFN-γ-sufficient or -deficient T-cell lines was used to examine the development of new clinical responses associated with the spinal cord and cerebellum at various times after EAE initiation. Previous inflammation within either cerebellum or spinal cord allowed subsequent T-cell driven inflammation within that tissue regardless of IFN-γ presence. Further, T-cell IFN-γ production after initial lesion formation exacerbated disease within the cerebellum, suggesting that IFN-γ plays different roles at different stages of cerebellar disease. For the spinal cord, IFN-γ-deficient cells (that are ordinarily cerebellum disease initiators) were capable of driving new spinal-cord-associated clinical symptoms more than 60 days after the initial acute EAE resolution. These data suggest that previous inflammation modulates the molecular requirements for new neuroinflammation development. © 2012 Blackwell Publishing Ltd.

A Prospective Study of Marine Phytoplankton and Reported Illness Among Recreational Beachgoers in Puerto Rico, 2009.

PubMed

Lin, Cynthia J; Wade, Timothy J; Sams, Elizabeth A; Dufour, Alfred P; Chapman, Andrew D; Hilborn, Elizabeth D

2016-04-01

Blooms of marine phytoplankton may adversely affect human health. The potential public health impact of low-level exposures is not well established, and few prospective cohort studies of recreational exposures to marine phytoplankton have been conducted. We evaluated the association between phytoplankton cell counts and subsequent illness among recreational beachgoers. We recruited beachgoers at Boquerón Beach, Puerto Rico, during the summer of 2009. We conducted interviews at three time points to assess baseline health, water activities, and subsequent illness. Daily water samples were quantitatively assayed for phytoplankton cell count. Logistic regression models, adjusted for age and sex, were used to assess the association between exposure to three categories of phytoplankton concentration and subsequent illness. During 26 study days, 15,726 individuals successfully completed all three interviews. Daily total phytoplankton cell counts ranged from 346 to 2,012 cells/mL (median, 712 cells/mL). The category with the highest (≥ 75th percentile) total phytoplankton cell count was associated with eye irritation [adjusted odds ratio (OR) = 1.30; 95% confidence interval (CI): 1.01, 1.66], rash (OR = 1.27; 95% CI: 1.02, 1.57), and earache (OR = 1.25; 95% CI: 0.88, 1.77). In phytoplankton group-specific analyses, the category with the highest Cyanobacteria counts was associated with respiratory illness (OR = 1.37; 95% CI: 1.12, 1.67), rash (OR = 1.32; 95% CI: 1.05, 1.66), eye irritation (OR = 1.25; 95% CI: 0.97, 1.62), and earache (OR = 1.35; 95% CI: 0.95, 1.93). We found associations between recreational exposure to marine phytoplankton and reports of eye irritation, respiratory illness, and rash. We also found that associations varied by phytoplankton group, with Cyanobacteria having the strongest and most consistent associations. Lin CJ, Wade TJ, Sams EA, Dufour AP, Chapman AD, Hilborn ED. 2016. A prospective study of marine phytoplankton and reported illness among recreational beachgoers in Puerto Rico, 2009. Environ Health Perspect 124:477-483; http://dx.doi.org/10.1289/ehp.1409558.

Spermidine/spermine N1-acetyltransferase (SSAT) activity in human small-cell lung carcinoma cells following transfection with a genomic SSAT construct.

PubMed

Murray-Stewart, Tracy; Applegren, Nancy B; Devereux, Wendy; Hacker, Amy; Smith, Renee; Wang, Yanlin; Casero, Robert A

2003-07-15

Spermidine/spermine N (1)-acetyltransferase (SSAT) activity is typically highly inducible in non-small-cell lung carcinomas in response to treatment with anti-tumour polyamine analogues, and this induction is associated with subsequent cell death. In contrast, cells of the small-cell lung carcinoma (SCLC) phenotype generally do not respond to these compounds with an increase in SSAT activity, and usually are only moderately affected with respect to growth. The goal of the present study was to produce an SSAT-overexpressing SCLC cell line to further investigate the role of SSAT in response to these anti-tumour analogues. To accomplish this, NCI-H82 SCLC cells were stably transfected with plasmids containing either the SSAT genomic sequence or the corresponding cDNA sequence. Individual clones were selected based on their ability to show induced SSAT activity in response to exposure to a polyamine analogue, and an increase in the steady-state SSAT mRNA level. Cells transfected with the genomic sequence exhibited a significant increase in basal SSAT mRNA expression, as well as enhanced SSAT activity, intracellular polyamine pool depletion and growth inhibition following treatment with the analogue N (1), N (11)-bis(ethyl)norspermine. Cells containing the transfected cDNA also exhibited an increase in the basal SSAT mRNA level, but remained phenotypically similar to vector control cells with respect to their response to analogue exposure. These studies indicate that both the genomic SSAT sequence and polyamine analogue exposure play a role in the transcriptional and post-transcriptional regulation and subsequent induction of SSAT activity in these cells. Furthermore, this is the first production of a cell line capable of SSAT protein induction from a generally unresponsive parent line.

A Benzothiazole Derivative (5g) Induces DNA Damage And Potent G2/M Arrest In Cancer Cells.

PubMed

Hegde, Mahesh; Vartak, Supriya V; Kavitha, Chandagirikoppal V; Ananda, Hanumappa; Prasanna, Doddakunche S; Gopalakrishnan, Vidya; Choudhary, Bibha; Rangappa, Kanchugarakoppal S; Raghavan, Sathees C

2017-05-31

Chemically synthesized small molecules play important role in anticancer therapy. Several chemical compounds have been reported to damage the DNA, either directly or indirectly slowing down the cancer cell progression by causing a cell cycle arrest. Direct or indirect reactive oxygen species formation causes DNA damage leading to cell cycle arrest and subsequent cell death. Therefore, identification of chemically synthesized compounds with anticancer potential is important. Here we investigate the effect of benzothiazole derivative (5g) for its ability to inhibit cell proliferation in different cancer models. Interestingly, 5g interfered with cell proliferation in both, cell lines and tumor cells leading to significant G2/M arrest. 5g treatment resulted in elevated levels of ROS and subsequently, DNA double-strand breaks (DSBs) explaining observed G2/M arrest. Consistently, we observed deregulation of many cell cycle associated proteins such as CDK1, BCL2 and their phosphorylated form, CyclinB1, CDC25c etc. Besides, 5g treatment led to decreased levels of mitochondrial membrane potential and activation of apoptosis. Interestingly, 5g administration inhibited tumor growth in mice without significant side effects. Thus, our study identifies 5g as a potent biochemical inhibitor to induce G2/M phase arrest of the cell cycle, and demonstrates its anticancer properties both ex vivo and in vivo.

5'-adenosine monophosphate is the neutrophil-derived paracrine factor that elicits chloride secretion from T84 intestinal epithelial cell monolayers.

PubMed Central

Madara, J L; Patapoff, T W; Gillece-Castro, B; Colgan, S P; Parkos, C A; Delp, C; Mrsny, R J

1993-01-01

Neutrophil transmigration across intestinal epithelia is thought to contribute to epithelial dysfunction and characterizes many inflammatory intestinal diseases. Neutrophils activated by factors, normally present in the lumen, release a neutrophil-derived secretagogue activity to which intestinal epithelia respond with an electrogenic chloride secretion, the transport event which underlies secretory diarrhea. Using sequential ultrafiltration, column chromatographic, and mass and Raman spectroscopic techniques, neutrophil-derived secretagogue was identified as 5'-AMP. Additional studies suggested that neutrophil-derived 5'-AMP is subsequently converted to adenosine at the epithelial cell surface by ecto-5'-nucleotidase and that adenosine subsequently activates intestinal secretion through adenosine receptors on the apical membrane of target intestinal epithelial cells. These findings suggest that this ATP metabolite may serve as a neutrophil-derived paracrine mediator that contributes to secretory diarrhea in states of intestinal inflammation. PMID:8486793

Real space flight travel is associated with ultrastructural changes, cytoskeletal disruption and premature senescence of HUVEC.

PubMed

Kapitonova, M Y; Muid, S; Froemming, G R A; Yusoff, W N W; Othman, S; Ali, A M; Nawawi, H M

2012-12-01

Microgravity, hypergravity, vibration, ionizing radiation and temperature fluctuations are major factors of outer space flight affecting human organs and tissues. There are several reports on the effect of space flight on different human cell types of mesenchymal origin while information regarding changes to vascular endothelial cells is scarce. Ultrastructural and cytophysiological features of macrovascular endothelial cells in outer space flight and their persistence during subsequent culturing were demonstrated in the present investigation. At the end of the space flight, endothelial cells displayed profound changes indicating cytoskeletal lesions and increased cell membrane permeability. Readapted cells of subsequent passages exhibited persisting cytoskeletal changes, decreased metabolism and cell growth indicating cellular senescence.

Erythrocyte ion channels in regulation of apoptosis.

PubMed

Lang, Florian; Birka, Christina; Myssina, Svetlana; Lang, Karl S; Lang, Philipp A; Tanneur, Valerie; Duranton, Christophe; Wieder, Thomas; Huber, Stephan M

2004-01-01

Erythrocytes lack mitochondria and nuclei, key organelles in the regulation of apoptosis. Until recently, erythrocytes were thus not considered subject to this type of cell death. However, exposure of erythrocytes to the Ca2+ ionophore ionomycin was shown to induce cell shrinkage, cell membrane blebbing and breakdown of phosphatidylserine asymmetry with subsequent phosphatidylserine exposure at the cell surface, all typical features of apoptosis. Further studies revealed the participation of ion channels in the regulation of erythrocyte "apoptosis." Osmotic shock, oxidative stress and energy depletion all activate a Ca2(+)-permeable non-selective cation channel in the erythrocyte cell membrane. The subsequent increase of Ca2+ concentration stimulates a scramblase leading to breakdown of cell membrane phosphatidylserine asymmetry and activates Ca2+ sensitive K+ (Gardos) channels leading to KCl loss and (further) cell shrinkage. Phosphatidylserine exposure and cell shrinkage are blunted in the nominal absence of extracellular Ca2+, in the presence of the cation channel inhibitors amiloride or ethylisopropylamiloride, at increased extracellular K+ or in the presence of the Gardos channel inhibitors clotrimazole or charybdotoxin. Thus, increase of cytosolic Ca2+ and cellular loss of K+ participate in the triggering of erythrocyte scramblase. Nevertheless, phosphatidylserine exposure is not completely abrogated in the nominal absence of Ca2+, pointing to additional Ca2(+)-independent pathways. One of those is activation of sphingomyelinase with subsequent formation of ceramide which in turn leads to stimulation of erythrocyte scramblase. The exposure of phosphatidylserine at the extracellular face of the cell membrane stimulates phagocytes to engulf the apoptotic erythrocytes. Thus, sustained activation of the cation channels eventually leads to clearance of affected erythrocytes from peripheral blood. Erythropoietin inhibits the non-selective cation channel and thus interferes with erythrocyte "apoptosis." Susceptibility to scramblase activation is enhanced in thalassemia, sickle cell disease and glucose-6-phosphate dehydrogenase deficiency. Infection with Plasmodium falciparum leads to activation of the cation channel eventually triggering erythrocyte "apoptosis."

Alendronate promotes bone formation by inhibiting protein prenylation in osteoblasts in rat tooth replantation model.

PubMed

Komatsu, Koichiro; Shimada, Akemi; Shibata, Tatsuya; Wada, Satoshi; Ideno, Hisashi; Nakashima, Kazuhisa; Amizuka, Norio; Noda, Masaki; Nifuji, Akira

2013-11-01

Bisphosphonates (BPs) are a major class of antiresorptive drug, and their molecular mechanisms of antiresorptive action have been extensively studied. Recent studies have suggested that BPs target bone-forming cells as well as bone-resorbing cells. We previously demonstrated that local application of a nitrogen-containing BP (N-BP), alendronate (ALN), for a short period of time increased bone tissue in a rat tooth replantation model. Here, we investigated cellular mechanisms of bone formation by ALN. Bone histomorphometry confirmed that bone formation was increased by local application of ALN. ALN increased proliferation of bone-forming cells residing on the bone surface, whereas it suppressed the number of tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts in vivo. Moreover, ALN treatment induced more alkaline phosphatase-positive and osteocalcin-positive cells on the bone surface than PBS treatment. In vitro studies revealed that pulse treatment with ALN promoted osteocalcin expression. To track the target cells of N-BPs, we applied fluorescence-labeled ALN (F-ALN) in vivo and in vitro. F-ALN was taken into bone-forming cells both in vivo and in vitro. This intracellular uptake was inhibited by endocytosis inhibitors. Furthermore, the endocytosis inhibitor dansylcadaverine (DC) suppressed ALN-stimulated osteoblastic differentiation in vitro and it suppressed the increase in alkaline phosphatase-positive bone-forming cells and subsequent bone formation in vivo. DC also blocked the inhibition of Rap1A prenylation by ALN in the osteoblastic cells. These data suggest that local application of ALN promotes bone formation by stimulating proliferation and differentiation of bone-forming cells as well as inhibiting osteoclast function. These effects may occur through endocytic incorporation of ALN and subsequent inhibition of protein prenylation.

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

Greenberg, S.D.; Smith, S.; Swank, P.R.

Visual cell profiles were used to analyze the distribution of atypical bronchial cells in sputum specimens from cigarette-smoking volunteers, cigarette-smoking asbestos workers and cigarette-smoking uranium miners. The preliminary results of these sputum visual cell profile studies have demonstrated distinctive distributions of bronchial cell atypias in progressive patterns of squamous metaplasia, mild, moderate and severe atypias and carcinoma, similar to those the authors have previously reported using cell image analysis techniques to determine an atypia status index (ASI). The information gained from this study will be helpful in further validating this ASI and subsequently achieving the ultimate goal of employing cellmore » image analysis for the rapid and precise identification of premalignant atypias in sputum.« less

Pregnancy at early age is associated with a reduction of progesterone-responsive cells and epithelial Wnt signaling in human breast tissue.

PubMed

Muenst, Simone; Mechera, Robert; Däster, Silvio; Piscuoglio, Salvatore; Ng, Charlotte K Y; Meier-Abt, Fabienne; Weber, Walter P; Soysal, Savas D

2017-04-04

Pregnancy at early age is the most significant modifiable factor which consistently decreases lifetime breast cancer risk. However, the underlying mechanisms haven't been conclusively identified. Studies in mice suggest a reduction in progesterone-receptor (PR) sensitive epithelial cells as well as a downregulation of the Wnt signaling pathway as being one of the main mechanisms for the protective effect of early pregnancy. The aim of our study was to validate these findings in humans. We collected benign breast tissue of 125 women who had been stratified according to age at first pregnancy and the occurrence of subsequent breast cancer, and performed immunohistochemistry for PR, Wnt4 and the Wnt-target Versican. The number of PR positive epithelial cells was significantly lower in the group of women with early pregnancy and no subsequent breast cancer compared to the group of nulliparous women with subsequent invasive breast cancer (p = 0.0135). In women with early pregnancy, expression of Versican and Wnt4 was significantly lower compared to nulliparous women (p = 0.0036 and p = 0.0241 respectively), and Versican expression was also significant lower compared to women with late pregnancy (p < 0.0001). Our results confirm prior observations in mice and suggest a role of downregulation of epithelial Wnt signaling in the protective effect of early pregnancy in humans. This results in a decreased proliferation of stem/progenitor cells; therefore, the Wnt signaling pathway may represent a potential target for breast cancer prevention in humans.

Production of propyl gallate in nonaqueous medium using cell-associated tannase of Bacillus massiliensis: effect of various parameters and statistical optimization.

PubMed

Aithal, Mahesh; Belur, Prasanna D

2013-01-01

Enzymatic synthesis of propyl gallate in an organic solvent was studied using cell-associated tannase (E.C. 3.1.1.20) of Bacillus massiliensis. Lyophilized biomass showing tannase activity was used as a biocatalyst. The influence of buffer pH and strength, water activity, temperature, biocatalyst loading, gallic acid concentration, and 1-propanol concentration was studied by the one-factor-at-a-time method. Subsequently, response surface methodology was applied based on a central composite design to determine the effects of three independent variables (biocatalyst loading, gallic acid concentration, and 1-propanol concentration) and their mutual interactions. A total of 20 experiments were conducted, and a statistical model was developed, which predicted the maximum propyl gallate yield of 20.28 μg/mL in the reaction mixture comprising 40.4 mg biocatalyst, 0.4 mM gallic acid, and 6.52 % (v/v) 1-propanol in 9.5 mL benzene at 30°C. The subsequent verification experiments established the validity of the model. Under optimal conditions, 25% conversion of gallic acid to propyl gallate was achieved on a molar basis. The absence of the need for enzyme purification and subsequent immobilization steps and good conversion efficiency makes this enzyme system an interesting one. Reports on the applications of bacterial whole cell systems for synthetic reactions in organic solvents are scarce, and perhaps this is the first report on bacterial cell-associated tannase-mediated esterification in a nonaqueous medium. © 2013 International Union of Biochemistry and Molecular Biology, Inc.

Evaluation of a cell phone-based physical activity diary.

PubMed

Sternfeld, Barbara; Jiang, Sheng-Fang; Picchi, Teresa; Chasan-Taber, Lisa; Ainsworth, Barbara; Quesenberry, Charles P

2012-03-01

Physical activity (PA) diaries reduce the recall error inherent in self-reported PA but are burdensome. The purpose of this study was to compare a cell phone-based diary with a paper diary and examine the reliability and validity of the cell phone diary. In a pilot study, 25 women and 23 men, age 45-65 yr, completed cell phone and paper PA diaries 4 d·wk(-1) for three consecutive weeks and a user satisfaction survey. In the subsequent validation study, 623 middle-age participants (52.5% women) were asked to complete the cell phone diary and wear an accelerometer for two 7-d periods, approximately 6 months apart. They also completed two PA questionnaires. Fitness, body mass index, and percent body fat were obtained as indirect validation criteria. Estimates of PA from the cell phone and paper diaries were similar (mean within person difference = -43.8 MET·min·d(-1) of total PA, SD = 360, P = 0.49, 7.4 min·d(-1) of moderate-vigorous PA, SD = 66, P = 0.53). Users preferred the cell phone diary over the paper diary (59.6% vs 35.4%). In the subsequent study, intraclass correlations for the cell phone diary ranged from 0.55 for light PA to 0.63 for vigorous PA. Although PA estimates from the cell phone diary were generally significantly higher than those from the accelerometer and the questionnaires, correlations for moderate and vigorous PA were moderate (ρ = 0.25-0.59 with the questionnaires and 0.27-0.35 with the accelerometer). The correlations between the cell phone diary and the indirect validation criteria were generally in the expected direction and of moderate magnitude. A cell phone-based PA diary is equivalent to a paper diary, acceptable to users, and a relatively reliable and valid approach to self-reported PA.

Clonal Evolution through Loss of Chromosomes and Subsequent Polyploidization in Chondrosarcoma

PubMed Central

Olsson, Linda; Paulsson, Kajsa; Bovée, Judith V. M. G.; Nord, Karolin H.

2011-01-01

Near-haploid chromosome numbers have been found in less than 1% of cytogenetically reported tumors, but seem to be more common in certain neoplasms including the malignant cartilage-producing tumor chondrosarcoma. By a literature survey of published karyotypes from chondrosarcomas we could confirm that loss of chromosomes resulting in hyperhaploid-hypodiploid cells is common and that these cells may polyploidize. Sixteen chondrosarcomas were investigated by single nucleotide polymorphism (SNP) array and the majority displayed SNP patterns indicative of a hyperhaploid-hypodiploid origin, with or without subsequent polyploidization. Except for chromosomes 5, 7, 19, 20 and 21, autosomal loss of heterozygosity was commonly found, resulting from chromosome loss and subsequent duplication of monosomic chromosomes giving rise to uniparental disomy. Additional gains, losses and rearrangements of genetic material, and even repeated rounds of polyploidization, may affect chondrosarcoma cells resulting in highly complex karyotypes. Loss of chromosomes and subsequent polyploidization was not restricted to a particular chondrosarcoma subtype and, although commonly found in chondrosarcoma, binucleated cells did not seem to be involved in these events. PMID:21949816

Is Dosage Important? Examining Head Start Preschoolers' Language and Literacy Learning after One versus Two Years of "ExCELL"

ERIC Educational Resources Information Center

Hindman, Annemarie H.; Wasik, Barbara A.

2017-01-01

The current study examined whether Head Start children who experienced a high-quality preschool intervention, "Exceptional Coaching for Early Language and Literacy" ("ExCELL"), as three-year-olds began the subsequent pre-kindergarten (or four-year-old) year with stronger language and literacy skills than same-age peers who…

GATA3 controls the specification of prosensory domain and neuronal survival in the mouse cochlea

PubMed Central

Luo, Xiong-jian; Deng, Min; Xie, Xiaoling; Huang, Liang; Wang, Hui; Jiang, Lichun; Liang, Guoqing; Hu, Fang; Tieu, Roger; Chen, Rui; Gan, Lin

2013-01-01

HDR syndrome (also known as Barakat syndrome) is a developmental disorder characterized by hypoparathyroidism, sensorineural deafness and renal disease. Although genetic mapping and subsequent functional studies indicate that GATA3 haplo-insufficiency causes human HDR syndrome, the role of Gata3 in sensorineural deafness and auditory system development is largely unknown. In this study, we show that Gata3 is continuously expressed in the developing mouse inner ear. Conditional knockout of Gata3 in the developing inner ear disrupts the morphogenesis of mouse inner ear, resulting in a disorganized and shortened cochlear duct with significant fewer hair cells and supporting cells. Loss of Gata3 function leads to the failure in the specification of prosensory domain and subsequently, to increased cell death in the cochlear duct. Moreover, though the initial generation of cochleovestibular ganglion (CVG) cells is not affected in Gata3-null mice, spiral ganglion neurons (SGNs) are nearly depleted due to apoptosis. Our results demonstrate the essential role of Gata3 in specifying the prosensory domain in the cochlea and in regulating the survival of SGNs, thus identifying a molecular mechanism underlying human HDR syndrome. PMID:23666531

[Therapeutic cloning. Biology, perspectives and alternatives].

PubMed

Maddox-Hyttel, Poul

2003-02-24

Certain diseases are caused by or cause irreversible loss of cells and may in the future be treated by cell-based therapies where spare cells are introduced into the body. Therapeutic cloning constitutes a scientifically and ethically challenging route to the generation of autologous patient specific spare cells: Stem cells for subsequent differentiation and transplantation are isolated from one week old embryos, which are produced by cloning by nuclear transfer from normal cells retrieved from a patient. Research in therapeutic cloning should be pursued in line with alternative strategies for obtaining stem cells. Finally, the molecular biology of cloning by nuclear transfer may hold the key to understanding trans-differentiation, which ultimately may allow for de-differentiation and subsequent re-differentiation of adult somatic cells for therapeutic purposes.

Genetic changes in mammalian cells transformed by helium ions

NASA Astrophysics Data System (ADS)

Durante, M.; Grossi, G.; Yang, T. C.; Roots, R.

Midterm Syrian Hamster embryo (SHE) cells were employed to study high LET-radiation induced tumorigenesis. Normal SHE cells (secondary passage) were irradiated with accelerated helium ions at an incident energy of 22 MeV/u (9-10 keV/μm). Transformed clones were isolated after growth in soft agar of cells obtained from the foci of the initial monolayer plated postirradiation. To study the progression process of malignant transformation, the transformed clones were followed by monolayer subculturing for prolonged periods of time. Subsequently, neoplasia tests in nude mice were done. In this work, however, we have focused on karyotypic changes in the banding patterns of the chromosomes during the early part of the progressive process of cell transformation for helium ion-induced transformed cells.

Contrasting Responses of Kupffer Cells and Inflammatory Mononuclear Phagocytes to Biliary Obstruction in a Mouse Model of Cholestatic Liver Injury

PubMed Central

Duwaerts, Caroline C.; Gehring, Stephan; Cheng, Chao-Wen; van Rooijen, Nico; Gregory, Stephen H.

2012-01-01

Background Biliary obstruction and cholestasis are serious complications of many liver diseases. While resident hepatic macrophages (Kupffer cells) are frequently implicated in disease progression, most studies fail to differentiate the contribution of Kupffer cells and inflammatory mononuclear phagocytes (iMNPs) that infiltrate the liver subsequent to obstruction. Aim This study was undertaken to examine the roles and potential interactions of these two disparate mononuclear phagocyte populations in hepatic injury attending cholestasis. Methods Female, C57Bl/6 mice were injected with magnetic beads on day three prior to sham operation or bile duct ligation (BDL) in order to facilitate subsequent Kupffer cell isolation. Three days post surgery, animals were euthanized, and bead-containing Kupffer cells and iMNPs were separated, purified, and analyzed. To examine the ability of Kupffer cells to modulate iMNP activity, iMNPs were isolated from the livers of intact and Kupffer cell-depleted mice on day 3 post-surgery and compared. Results Purified Kupffer cells and iMNP populations obtained from BDL mice exhibited heterogeneous morphologies rendering them visually indistinguishable. iMNPs, however, were characterized by the increased expression of Ly-6C and CD11b and the elevated production of chemokines/cytokines characteristic of inflammatory cells. In the absence of Kupffer cells, iMNPs immigrating to the liver following BDL exhibited significant decreases in CD11b and Ly-6C expression, and in pro-inflammatory chemokine/cytokine production. Conclusions Kupffer cells and iMNPs exhibit disparate biological responses to biliary obstruction and cholestasis. Kupffer cells play a key role in regulating iMNP influx and activity. PMID:23240869

Efficient Purification and Release of Circulating Tumor Cells by Synergistic Effect of Biomarker and SiO2 @Gel-Microbead-Based Size Difference Amplification.

PubMed

Huang, Qinqin; Cai, Bo; Chen, Bolei; Rao, Lang; He, Zhaobo; He, Rongxiang; Guo, Feng; Zhao, Libo; Kondamareddy, Kiran Kumar; Liu, Wei; Guo, Shishang; Zhao, Xing-Zhong

2016-07-01

Microfluidics-based circulating tumor cell (CTC) isolation is achieved by using gelatin-coated silica microbeads conjugated to CTC-specific antibodies. Bead-binding selectively enlarges target cell size, providing efficient high-purity capture. CTCs captured can be further released non-invasively. This stratagem enables high-performance CTC isolation for subsequent studies. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Kinetics of antibody-induced modulation of respiratory syncytial virus antigens in a human epithelial cell line

PubMed Central

Sarmiento, Rosa E; Tirado, Rocio G; Valverde, Laura E; Gómez-Garcia, Beatriz

2007-01-01

Background The binding of viral-specific antibodies to cell-surface antigens usually results in down modulation of the antigen through redistribution of antigens into patches that subsequently may be internalized by endocytosis or may form caps that can be expelled to the extracellular space. Here, by use of confocal-laser-scanning microscopy we investigated the kinetics of the modulation of respiratory syncytial virus (RSV) antigen by RSV-specific IgG. RSV-infected human epithelial cells (HEp-2) were incubated with anti-RSV polyclonal IgG and, at various incubation times, the RSV-cell-surface-antigen-antibody complexes (RSV Ag-Abs) and intracellular viral proteins were detected by indirect immunoflourescence. Results Interaction of anti-RSV polyclonal IgG with RSV HEp-2 infected cells induced relocalization and aggregation of viral glycoproteins in the plasma membrane formed patches that subsequently produced caps or were internalized through clathrin-mediated endocytosis participation. Moreover, the concentration of cell surface RSV Ag-Abs and intracellular viral proteins showed a time dependent cyclic variation and that anti-RSV IgG protected HEp-2 cells from viral-induced death. Conclusion The results from this study indicate that interaction between RSV cell surface proteins and specific viral antibodies alter the expression of viral antigens expressed on the cells surface and intracellular viral proteins; furthermore, interfere with viral induced destruction of the cell. PMID:17608950

Cell cycle tracking for irradiated and unirradiated bystander cells in a single colony with exposure to a soft X-ray microbeam.

PubMed

Kaminaga, Kiichi; Noguchi, Miho; Narita, Ayumi; Hattori, Yuya; Usami, Noriko; Yokoya, Akinari

2016-11-01

To establish a new experimental technique to explore the photoelectric and subsequent Auger effects on the cell cycles of soft X-ray microbeam-irradiated cells and unirradiated bystander cells in a single colony. Several cells located in the center of a microcolony of HeLa-Fucci cells consisting of 20-80 cells were irradiated with soft X-ray (5.35 keV) microbeam using synchrotron radiation as a light source. All cells in the colony were tracked for 72 h by time-lapse microscopy imaging. Cell cycle progression, division, and death of each cell in the movies obtained were analyzed by pedigree assay. The number of cell divisions in the microcolony was also determined. The fates of these cells were clarified by tracking both irradiated and unirradiated bystander cells. Irradiated cells showed significant cell cycle retardation, explosive cell death, or cell fusion after a few divisions. These serious effects were also observed in 15 and 26% of the bystander cells for 10 and 20 Gy irradiation, respectively, and frequently appeared in at least two daughter or granddaughter cells from a single-parent cell. We successfully tracked the fates of microbeam-irradiated cells and unirradiated bystander cells with live cell recordings, which have revealed the dynamics of soft X-ray irradiated and unirradiated bystander cells for the first time. Notably, cell deaths or cell cycle arrests frequently arose in closely related cells. These details would not have been revealed by a conventional immunostaining imaging method. Our approach promises to reveal the dynamic cellular effects of soft X-ray microbeam irradiation and subsequent Auger processes from various endpoints in future studies.

Laser microbeam irradiation and renucleation of mouse eggs. Final progress report, July 1, 1979-December 31, 1983

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

Lin, T.P.

1983-01-01

We have combined laser microbeam irradiation of mouse egg nuclei with fusion to donor cell nuclei in order to develop a new procedure for transferring nuclei into mammalian eggs. We have been using virus-treated cells injected into the perivitelline for fusion with egg cells. Binucleate cells inside the zona pellucida were often produced indicating nuclear transfer between cells had occurred. To prevent the formation of such abortive polyploidy, host nuclei were inactivated with a laser microbeam. The subsequent cleavage of the microirradiated eggs has been studied.

Minocycline attenuates colistin-induced neurotoxicity via suppression of apoptosis, mitochondrial dysfunction and oxidative stress.

PubMed

Dai, Chongshan; Ciccotosto, Giuseppe D; Cappai, Roberto; Wang, Yang; Tang, Shusheng; Xiao, Xilong; Velkov, Tony

2017-06-01

Neurotoxicity is an adverse effect patients experience during colistin therapy. The development of effective neuroprotective agents that can be co-administered during polymyxin therapy remains a priority area in antimicrobial chemotherapy. The present study investigates the neuroprotective effect of the synergistic tetracycline antibiotic minocycline against colistin-induced neurotoxicity. The impact of minocycline pretreatment on colistin-induced apoptosis, caspase activation, oxidative stress and mitochondrial dysfunction were investigated using cultured mouse neuroblastoma-2a (N2a) and primary cortical neuronal cells. Colistin-induced neurotoxicity in mouse N2a and primary cortical cells gives rise to the generation of reactive oxygen species (ROS) and subsequent cell death via apoptosis. Pretreatment of the neuronal cells with minocycline at 5, 10 and 20 μM for 2 h prior to colistin (200 μM) exposure (24 h), had an neuroprotective effect by significantly decreasing intracellular ROS production and by upregulating the activities of the anti-ROS enzymes superoxide dismutase and catalase. Minocycline pretreatment also protected the cells from colistin-induced mitochondrial dysfunction, caspase activation and subsequent apoptosis. Immunohistochemical imaging studies revealed colistin accumulates within the dendrite projections and cell body of primary cortical neuronal cells. To our knowledge, this is first study demonstrating the protective effect of minocycline on colistin-induced neurotoxicity by scavenging of ROS and suppression of apoptosis. Our study highlights that co-administration of minocycline kills two birds with one stone: in addition to its synergistic antimicrobial activity, minocycline could potentially ameliorate unwanted neurotoxicity in patients undergoing polymyxin therapy. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Biocompatibility of functionalized boron phosphate (BPO4) nanoparticles for boron neutron capture therapy (BNCT) application.

PubMed

Achilli, Cesare; Grandi, Stefania; Ciana, Annarita; Guidetti, Gianni F; Malara, Alessandro; Abbonante, Vittorio; Cansolino, Laura; Tomasi, Corrado; Balduini, Alessandra; Fagnoni, Maurizio; Merli, Daniele; Mustarelli, Piercarlo; Canobbio, Ilaria; Balduini, Cesare; Minetti, Giampaolo

2014-04-01

Boron neutron capture therapy (BNCT) is a radiotherapy treatment based on the accumulation in the tumor of a (10)B-containing drug and subsequent irradiation with low energy neutrons, which bring about the decay of (10)B to (7)Li and an α particle, causing the death of the neoplastic cell. The effectiveness of BNCT is limited by the low delivery and accumulation of the used boron-containing compounds. Here we report the development and the characterization of BPO4 nanoparticles (NPs) as a novel possible alternative drug for BNCT. An extensive analysis of BPO4 NP biocompatibility was performed using both mature blood cells (erythrocytes, neutrophils and platelets) and a model of hematopoietic progenitor cells. A time- and concentration-dependent cytotoxicity study was performed on neoplastic coloncarcinoma and osteosarcoma cell lines. BPO4 functionalization with folic acid, introduced to improve the uptake by tumor cells, appeared to effectively limit the unwanted effects of NPs on the analyzed blood components. Boron neutron capture therapy (BNCT) is a radiotherapy treatment modality based on the accumulation of a (10)B-containing drug and subsequent irradiation with low energy neutrons, inducing the decay of (10)B to (7)Li and an α particle, causing neoplastic cell death. This team of authors reports on a folic acid functionalized BPO4 nanoparticle with improved characteristics compared with conventional BNCT approaches, as demonstrated in tumor cell lines, and hopefully to be followed by translational human studies. © 2014.

PD-1-PD-L1 immune-checkpoint blockade in malignant lymphomas.

PubMed

Wang, Yi; Wu, Ling; Tian, Chen; Zhang, Yizhuo

2018-02-01

Tumor cells can evade immune surveillance through overexpressing the ligands of checkpoint receptors on tumor cells or adjacent cells, leading T cells to anergy or exhaustion. Growing evidence of the interaction between tumor cells and microenvironment promoted the emergence of immune-checkpoint blockade. By targeting programmed cell death-1 (PD-1) pathway, cytotoxic activity of T cell is enhanced significantly and tumor cell lysis is induced subsequently. Currently, various antibodies against PD-1 and programmed death-ligand 1 (PD-L1) are under clinical studies in lymphomas. In this review, we outline the rationale for investigation of PD-1-PD-L1 immune-checkpoint blockade in lymphomas and discuss their prospect of applications in clinical treatment.

Safe sorting of GFP-transduced live cells for subsequent culture using a modified FACS vantage.

PubMed

Sørensen, T U; Gram, G J; Nielsen, S D; Hansen, J E

1999-12-01

A stream-in-air cell sorter enables rapid sorting to a high purity, but it is not well suited for sorting of infectious material due to the risk of airborne spread to the surroundings. A FACS Vantage cell sorter was modified for safe use with potentially HIV infected cells. Safety tests with bacteriophages were performed to evaluate the potential spread of biologically active material during cell sorting. Cells transduced with a retroviral vector carrying the gene for GFP were sorted on the basis of their GFP fluorescence, and GFP expression was followed during subsequent culture. The bacteriophage sorting showed that the biologically active material was confined to the sorting chamber. A failure mode simulating a nozzle blockage resulted in detectable droplets inside the sorting chamber, but no droplets could be detected when an additional air suction from the sorting chamber had been put on. The GFP transduced cells were sorted to 99% purity. Cells not expressing GFP at the time of sorting did not turn on the gene during subsequent culture. Un-sorted cells and cells sorted to be positive for GFP showed a decrease in the fraction of GFP positive cells during culture. Sorting of live infected cells can be performed safely and with no deleterious effects on vector expression using the modified FACS Vantage instrument. Copyright 1999 Wiley-Liss, Inc.

Asymmetric cell division during T cell development controls downstream fate

PubMed Central

Pham, Kim; Shimoni, Raz; Charnley, Mirren; Ludford-Menting, Mandy J.; Hawkins, Edwin D.; Ramsbottom, Kelly; Oliaro, Jane; Izon, David; Ting, Stephen B.; Reynolds, Joseph; Lythe, Grant; Molina-Paris, Carmen; Melichar, Heather; Robey, Ellen; Humbert, Patrick O.; Gu, Min

2015-01-01

During mammalian T cell development, the requirement for expansion of many individual T cell clones, rather than merely expansion of the entire T cell population, suggests a possible role for asymmetric cell division (ACD). We show that ACD of developing T cells controls cell fate through differential inheritance of cell fate determinants Numb and α-Adaptin. ACD occurs specifically during the β-selection stage of T cell development, and subsequent divisions are predominantly symmetric. ACD is controlled by interaction with stromal cells and chemokine receptor signaling and uses a conserved network of polarity regulators. The disruption of polarity by deletion of the polarity regulator, Scribble, or the altered inheritance of fate determinants impacts subsequent fate decisions to influence the numbers of DN4 cells arising after the β-selection checkpoint. These findings indicate that ACD enables the thymic microenvironment to orchestrate fate decisions related to differentiation and self-renewal. PMID:26370500

Pathologically Diagnosed Placenta Accreta and Hemorrhagic Morbidity in a Subsequent Pregnancy.

PubMed

Roeca, Cassandra; Little, Sarah E; Carusi, Daniela A

2017-02-01

To identify the relationship between pathologically diagnosed placenta accreta and risk of major morbidity in a subsequent pregnancy. We conducted a retrospective cohort study of patients with pathologically diagnosed placenta accreta in an index pregnancy who returned with a subsequent pregnancy at our academic center from 2007 to 2015. Subsequent delivery outcomes included minor, major, or no morbidity. Minor morbidity included estimated blood loss 500-1,500 cc for vaginal and 1,000-1,500 cc for cesarean delivery, transfusion of one to three units of red cells, and minor surgical procedures. Major morbidity included estimated blood loss greater than 1,500 cc, transfusion of greater than three units of red cells, uterine artery embolization, unplanned laparotomy, or hysterectomy. Three hundred thirty-nine patients with pathologically diagnosed accreta did not undergo hysterectomy, and 39 (11.5%) of these returned for subsequent delivery. Of these, 14 (36%) had accretas that had been identified clinically in the index pregnancy. Twenty-one (54%) experienced morbidity in the index pregnancy, 16 of these (76%) minor and five (24%) major. Of patients without morbidity in the first pregnancy, none experienced major morbidity in a subsequent pregnancy, whereas 6 of 21 (29%) with any index morbidity had a subsequent major morbid outcome (P=.02). Of those with a morbid index delivery, 25% had either a clinical or pathologic accreta diagnosis at follow-up compared with none of those who index accreta was nonmorbid (P=.05). Risk for major hemorrhagic morbidity after a prior pathologically diagnosed accreta depends on the clinical context. Preparation for major blood loss is indicated after any prior pregnancy complicated by hemorrhage or treatment of retained placenta with a pathologic accreta.

Crude Extracts, Flavokawain B and Alpinetin Compounds from the Rhizome of Alpinia mutica Induce Cell Death via UCK2 Enzyme Inhibition and in Turn Reduce 18S rRNA Biosynthesis in HT-29 Cells

PubMed Central

Abdullah, Rasedee; Kassim, Nur Kartinee Bt; Rosli, Rozita; Yeap, Swee Keong; Waziri, Peter; Etti, Imaobong Christopher; Bello, Muhammad Bashir

2017-01-01

Uridine-cytidine kinase 2 is an enzyme that is overexpressed in abnormal cell growth and its implication is considered a hallmark of cancer. Due to the selective expression of UCK2 in cancer cells, a selective inhibition of this key enzyme necessitates the discovery of its potential inhibitors for cancer chemotherapy. The present study was carried out to demonstrate the potentials of natural phytochemicals from the rhizome of Alpinia mutica to inhibit UCK2 useful for colorectal cancer. Here, we employed the used of in vitro to investigate the effectiveness of natural UCK2 inhibitors to cause HT-29 cell death. Extracts, flavokawain B, and alpinetin compound from the rhizome of Alpinia mutica was used in the study. The study demonstrated that the expression of UCK2 mRNA were substantially reduced in treated HT-29 cells. In addition, downregulation in expression of 18S ribosomal RNA was also observed in all treated HT-29 cells. This was confirmed by fluorescence imaging to measure the level of expression of 18S ribosomal RNA in live cell images. The study suggests the possibility of MDM2 protein was downregulated and its suppression subsequently activates the expression of p53 during inhibition of UCK2 enzyme. The expression of p53 is directly linked to a blockage of cell cycle progression at G0/G1 phase and upregulates Bax, cytochrome c, and caspase 3 while Bcl2 was deregulated. In this respect, apoptosis induction and DNA fragmentation were observed in treated HT-29 cells. Initial results from in vitro studies have shown the ability of the bioactive compounds of flavokawain B and alpinetin to target UCK2 enzyme specifically, inducing cell cycle arrest and subsequently leading to cancer cell death, possibly through interfering the MDM2-p53 signalling pathway. These phenomena have proven that the bioactive compounds could be useful for future therapeutic use in colon cancer. PMID:28103302

Crude Extracts, Flavokawain B and Alpinetin Compounds from the Rhizome of Alpinia mutica Induce Cell Death via UCK2 Enzyme Inhibition and in Turn Reduce 18S rRNA Biosynthesis in HT-29 Cells.

PubMed

Malami, Ibrahim; Abdul, Ahmad Bustamam; Abdullah, Rasedee; Kassim, Nur Kartinee Bt; Rosli, Rozita; Yeap, Swee Keong; Waziri, Peter; Etti, Imaobong Christopher; Bello, Muhammad Bashir

2017-01-01

Uridine-cytidine kinase 2 is an enzyme that is overexpressed in abnormal cell growth and its implication is considered a hallmark of cancer. Due to the selective expression of UCK2 in cancer cells, a selective inhibition of this key enzyme necessitates the discovery of its potential inhibitors for cancer chemotherapy. The present study was carried out to demonstrate the potentials of natural phytochemicals from the rhizome of Alpinia mutica to inhibit UCK2 useful for colorectal cancer. Here, we employed the used of in vitro to investigate the effectiveness of natural UCK2 inhibitors to cause HT-29 cell death. Extracts, flavokawain B, and alpinetin compound from the rhizome of Alpinia mutica was used in the study. The study demonstrated that the expression of UCK2 mRNA were substantially reduced in treated HT-29 cells. In addition, downregulation in expression of 18S ribosomal RNA was also observed in all treated HT-29 cells. This was confirmed by fluorescence imaging to measure the level of expression of 18S ribosomal RNA in live cell images. The study suggests the possibility of MDM2 protein was downregulated and its suppression subsequently activates the expression of p53 during inhibition of UCK2 enzyme. The expression of p53 is directly linked to a blockage of cell cycle progression at G0/G1 phase and upregulates Bax, cytochrome c, and caspase 3 while Bcl2 was deregulated. In this respect, apoptosis induction and DNA fragmentation were observed in treated HT-29 cells. Initial results from in vitro studies have shown the ability of the bioactive compounds of flavokawain B and alpinetin to target UCK2 enzyme specifically, inducing cell cycle arrest and subsequently leading to cancer cell death, possibly through interfering the MDM2-p53 signalling pathway. These phenomena have proven that the bioactive compounds could be useful for future therapeutic use in colon cancer.

Biological Basis for Chemoprevention of Ovarian Cancer

DTIC Science & Technology

1999-10-01

potent apoptotic effect on ovarian epithelial cells, the use of levonorgestrel in chemoprevention of ovarian cancer is being explored in chickens and...women. A chemoprevention trial is ongoing in chickens and we will begin a trial to determine whether levonorgestrel induces apoptosis in the ovarian...subsequent studies performed in vitro, we have induced apoptosis in epithelial cells treated with the progestin levonorgestrel . Progestin mediated apoptotic

The use of morphokinetics as a predictor of embryo implantation.

PubMed

Meseguer, Marcos; Herrero, Javier; Tejera, Alberto; Hilligsøe, Karen Marie; Ramsing, Niels Birger; Remohí, Jose

2011-10-01

Time-lapse observation presents an opportunity for optimizing embryo selection based on morphological grading as well as providing novel kinetic parameters, which may further improve accurate selection of viable embryos. The objective of this retrospective study was to identify the morphokinetic parameters specific to embryos that were capable of implanting. In order to compare a large number of embryos, with minimal variation in culture conditions, we have used an automatic embryo monitoring system. Using a tri-gas IVF incubator with a built-in camera designed to automatically acquire images at defined time points, we have simultaneously monitored up to 72 individual embryos without removing the embryos from the controlled environment. Images were acquired every 15 min in five different focal planes for at least 64 h for each embryo. We have monitored the development of transferred embryos from 285 couples undergoing their first ICSI cycle. The total number of transferred embryos was 522, of which 247 either failed to implant or fully implanted, with full implantation meaning that all transferred embryos in a treatment implanted. A detailed retrospective analysis of cleavage times, blastomere size and multinucleation was made for the 247 transferred embryos with either failed or full implantation. We found that several parameters were significantly correlated with subsequent implantation (e.g. time of first and subsequent cleavages as well as the time between cleavages). The most predictive parameters were: (i) time of division to 5 cells, t5 (48.8-56.6 h after ICSI); (ii) time between division to 3 cells and subsequent division to 4 cells, s2 (≤ 0.76 h) and (iii) duration of cell cycle two, i.e. time between division to 2 cells and division to 3 cells, cc2 (≤ 11.9 h). We also observed aberrant behavior such as multinucleation at the 4 cell stage, uneven blastomere size at the 2 cell stage and abrupt cell division to three or more cells, which appeared to largely preclude implantation. The image acquisition and time-lapse analysis system makes it possible to determine exact timing of embryo cleavages in a clinical setting. We propose a multivariable model based on our findings to classify embryos according to their probability of implantation. The efficacy of this classification will be evaluated in a prospective randomized study that ultimately will determine if implantation rates can be improved by time-lapse analysis.

Cellular and Humoral Immunity Protect against Vaginal Zika Virus Infection in Mice.

PubMed

Scott, Jason M; Lebratti, Tania J; Richner, Justin M; Jiang, Xiaoping; Fernandez, Estefania; Zhao, Haiyan; Fremont, Daved H; Diamond, Michael S; Shin, Haina

2018-01-17

Zika virus (ZIKV), which can cause devastating disease in fetuses of infected pregnant women, can be transmitted by mosquito inoculation and sexual routes. Little is known about immune protection against sexually transmitted ZIKV. In this study, we show that previous infection through intravaginal or subcutaneous routes with a contemporary Brazilian strain of ZIKV can protect against subsequent intravaginal challenge with a homologous strain. Both routes of inoculation induced high titers of ZIKV-specific and neutralizing antibody in serum and the vaginal lumen. Virus-specific T cells were recruited to and retained in the female reproductive tract after intravaginal and subcutaneous ZIKV infection. Studies in mice with genetic or acquired deficiencies in B and/or T cells demonstrated that both lymphocyte populations redundantly protect against intravaginal challenge in ZIKV-immune animals. Passive transfer of ZIKV immune IgG or T cells significantly limited intravaginal infection of naïve mice, although antibody more effectively prevented dissemination throughout the reproductive tract. Collectively, our experiments begin to establish the immune correlates of protection against intravaginal ZIKV infection, which should inform vaccination strategies in non-pregnant and pregnant women. IMPORTANCE The recent ZIKV epidemic resulted in devastating outcomes in fetuses and may affect reproductive health. Unlike other flaviviruses, ZIKV can be spread by sexual contact as well as a mosquito vector. While previous studies have identified correlates of protection for mosquito-mediated infection, few have focused on immunity against sexual transmission. As exposure to ZIKV via mosquito bite has likely occurred to many living in endemic areas, our study addresses whether this route of infection can protect against subsequent sexual exposure. We demonstrate that subcutaneous ZIKV infection can protect against subsequent vaginal infection by generating both local antiviral T cell and antibody responses. Our research begins to define the immune correlates of protection for ZIKV infection in the vagina and provides a foundation for testing ZIKV vaccines against sexual transmission. Copyright © 2018 American Society for Microbiology.

Efficient production and purification of functional bacteriorhodopsin with a wheat-germ cell-free system and a combination of Fos-choline and CHAPS detergents.

PubMed

Genji, Takahisa; Nozawa, Akira; Tozawa, Yuzuru

2010-10-01

Cell-free translation is one potential approach to the production of functional transmembrane proteins. We have now examined various detergents as supplements to a wheat-germ cell-free system in order to optimize the production and subsequent purification of a functional model transmembrane protein, bacteriorhodopsin. We found that Fos-choline and CHAPS detergents counteracted each other's inhibitory effects on cell-free translation activity and thereby allowed the efficient production and subsequent purification of functional bacteriorhodopsin in high yield. Copyright © 2010 Elsevier Inc. All rights reserved.

Receptor trafficking via the perinuclear recycling compartment accompanied by cell division is necessary for permanent neurotensin cell sensitization and leads to chronic mitogen-activated protein kinase activation.

PubMed

Toy-Miou-Leong, Mireille; Cortes, Catherine Llorens; Beaudet, Alain; Rostène, William; Forgez, Patricia

2004-03-26

Most G protein-coupled receptors are internalized after interaction with their respective ligand, a process that subsequently contributes to cell desensitization, receptor endocytosis, trafficking, and finally cell resensitization. Although cellular mechanisms leading to cell desensitization have been widely studied, those responsible for cell resensitization are still poorly understood. We examined here the traffic of the high affinity neurotensin receptor (NT1 receptor) following prolonged exposure to high agonist concentration. Fluorescence and confocal microscopy of Chinese hamster ovary, human neuroblastoma (CHP 212), and murine neuroblastoma (N1E-115) cells expressing green fluorescent protein-tagged NT1 receptor revealed that under prolonged treatment with saturating concentrations of neurotensin (NT) agonist, NT1 receptor and NT transiently accumulated in the perinuclear recycling compartment (PNRC). During this cellular event, cell surface receptors remained markedly depleted as detected by both confocal microscopy and (125)I-NT binding assays. In dividing cells, we observed that following prolonged NT agonist stimulation, NT1 receptors were removed from the PNRC, accumulated in dispersed vesicles inside the cytoplasm, and subsequently reappeared at the cell surface. This NT binding recovery allowed for constant cell sensitization and led to a chronic activation of mitogen-activated protein kinases p42 and p44. Under these conditions, the constant activation of NT1 receptor generates an oncogenic regulation. These observations support the potent role for neuropeptides, such as NT, in cancer progression.

In situ flat embedding of monolayers and cell relocation in the acrylic resin LR white for comparative light and electron microscopy studies.

PubMed

Steiner, M; Schöfer, C; Mosgoeller, W

1994-12-01

A simple and reliable method has been developed for the in situ LR White embedding of cell monolayers grown on glass cover-slips. Combined with cytochemical or immunological procedures, this technique allows light and/or electron microscopy investigations of a large number of cells in the same horizontal plane within a relatively short period of time. It can be applied to cells grown on microgrid finder cover-slips which allows a distinct site of even an individual cell of a monolayer to be studied at first at the light microscope level and subsequently at the electron microscope level. Hence, it is also suitable for controlling manipulation of single cells, followed by their serial sectioning after relocation in the electron microscope.

Ultrasound guided transplantation of enriched and cryopreserved spermatogonial cell suspension in goats.

PubMed

Kaul, G; Kaur, J; Rafeeqi, T A

2010-12-01

Spermatogonial stem cells transplantation provides a unique approach for studying spermatogenesis. Initially developed in mice, this technique has now been extended in farm animals and provides an alternative means to preserve valuable male germ line and to produce transgenic animals. The aim of this study was to enrich type A spermatogonial cells amongst the isolated cells from goat testis, to cryopreserve these enriched populations of cells and their subsequent transplantation in unrelated recipient goats under ultrasound guidance. The cells were isolated enzymatically and enriched by differential plating and separation on discontinuous percoll gradient. Ultrasound guided injection of trypan blue dye into rete testis resulted in 20-30% filling of the seminiferous tubules. Prior to transplantation, the cells were labelled with a fluorescent dye to trace donor cells in recipient seminiferous tubules after transplantation. The fluorescent-labelled cells were observed up to 12 weeks after transplantation. © 2009 Blackwell Verlag GmbH.

Comparison between the early cellular response to electron radiation and the production of tumors

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

Sinclair, Ian P.

1972-11-01

The aim of the study is to quantitate radiation-induced cell population changes in various epithelial components of rat skin and to correlate them, if possible with the subsequent production of tumors.

Carbon nanoparticles induce ceramide- and lipid raft-dependent signalling in lung epithelial cells: a target for a preventive strategy against environmentally-induced lung inflammation

PubMed Central

2012-01-01

Background Particulate air pollution in lung epithelial cells induces pathogenic endpoints like proliferation, apoptosis, and pro-inflammatory reactions. The activation of the epidermal growth factor receptor (EGFR) is a key event responsible for signalling events involving mitogen activated protein kinases specific for these endpoints. The molecular events leading to receptor activation however are not well understood. These events are relevant for the toxicological evaluation of inhalable particles as well as for potential preventive strategies in situations when particulate air pollution cannot be avoided. The current study therefore had the objective to elucidate membrane-coupled events leading to EGFR activation and the subsequent signalling cascade in lung epithelial cells. Furthermore, we aimed to identify the molecular target of ectoine, a biophysical active substance which we described to prevent carbon nanoparticle-induced lung inflammation. Methods Membrane signalling events were investigated in isolated lipid rafts from lung epithelial cells with regard to lipid and protein content of the signalling platforms. Using positive and negative intervention approaches, lipid raft changes, subsequent signalling events, and lung inflammation were investigated in vitro in lung epithelial cells (RLE-6TN) and in vivo in exposed animals. Results Carbon nanoparticle treatment specifically led to an accumulation of ceramides in lipid rafts. Detailed analyses demonstrated a causal link of ceramides and subsequent EGFR activation coupled with a loss of the receptor in the lipid raft fractions. In vitro and in vivo investigations demonstrate the relevance of these events for carbon nanoparticle-induced lung inflammation. Moreover, the compatible solute ectoine was able to prevent ceramide-mediated EGFR phosphorylation and subsequent signalling as well as lung inflammation in vivo. Conclusion The data identify a so far unknown event in pro-inflammatory signalling and contribute to the understanding of particle cell interaction and therefore to risk identification and risk assessment of inhalable xenobiotics. Moreover, as this cellular reaction can be prevented by the well tolerated substance ectoine, a molecular preventive strategy for susceptible persons against airway inflammation is proposed. PMID:23228165

Immunization of mice with baculovirus-derived recombinant SV40 large tumour antigen induces protective tumour immunity to a lethal challenge with SV40-transformed cells.

PubMed Central

Shearer, M H; Bright, R K; Lanford, R E; Kennedy, R C

1993-01-01

In this study, we examined the humoral immune responses and in vivo tumour immunity induced by baculovirus recombinant simian virus 40 (SV40) large tumour antigen (rSV40 T-ag). BALB/c mice immunized with rSV40 T-ag produced antibody responses that recognized SV40 large tumour antigen (T-ag) by ELISA. Analysis of these anti-SV40 T-ag responses indicated that the antibodies recognized epitopes associated with both the carboxy and amino terminus of SV40 T-ag. This pattern of SV40 T-ag epitope recognition was similar to that observed in anti-SV40 T-ag responses induced by inoculation with irradiated SV40-transformed cells. Mice immunized with either rSV40 T-ag or with the inactivated transformed cells were protected from a subsequent in vivo lethal tumour challenge with live SV40-transformed cells. These studies suggest that humoral immune responses induced by rSV40 T-ag are similar in epitope specificity to that induced by inactivated SV40-transformed cells. In addition, recombinant tumour-specific antigens from papovaviruses, such as SV40, can be used to induce tumour immunity which protects from a subsequent lethal tumour challenge. This study may provide insight into the use of recombinant tumour antigens as putative tumour vaccines and in the development of active immunotherapeutic strategies for treating virus-induced cancers. PMID:7679059

Prostanoids and their receptors that modulate dendritic cell-mediated immunity.

PubMed

Gualde, Norbert; Harizi, Hedi

2004-08-01

Dendritic cells (DC) are essential for the initiation of immune responses by capturing, processing and presenting antigens to T cells. In addition to their important role as professional APC, they are able to produce immunosuppressive and pro-inflammatory prostanoids from arachidonic acid (AA) by the action of cyclooxygenase (COX) enzymes. In an autocrine and paracrine fashion, the secreted lipid mediators subsequently modulate the maturation, cytokine production, Th-cell polarizing ability, chemokine receptor expression, migration, and apoptosis of these extremely versatile APC. The biological actions of prostanoids, including their effects on APC-mediated immunity and acute inflammatory responses, are exerted by G protein-coupled receptors on plasma membrane. Some COX metabolites act as anti-inflammatory lipid mediators by binding to nuclear receptors and modulating DC functions. Although the role of cytokines in DC function has been studied extensively, the effects of prostanoids on DC biology have only recently become the focus of investigation. This review summarizes the current knowledge about the role of prostanoids and their receptors in modulating DC function and the subsequent immune responses.

Ionizing radiation-induced mutagenesis: radiation studies in Neurospora predictive for results in mammalian cells

NASA Technical Reports Server (NTRS)

Evans, H. H.; DeMarini, D. M.

1999-01-01

Ionizing radiation was the first mutagen discovered and was used to develop the first mutagenicity assay. In the ensuing 70+ years, ionizing radiation became a fundamental tool in understanding mutagenesis and is still a subject of intensive research. Frederick de Serres et al. developed and used the Neurospora crassa ad-3 system initially to explore the mutagenic effects of ionizing radiation. Using this system, de Serres et al. demonstrated the dependence of the frequency and spectra of mutations induced by ionizing radiation on the dose, dose rate, radiation quality, repair capabilities of the cells, and the target gene employed. This work in Neurospora predicted the subsequent observations of the mutagenic effects of ionizing radiation in mammalian cells. Modeled originally on the mouse specific-locus system developed by William L. Russell, the N. crassa ad-3 system developed by de Serres has itself served as a model for interpreting the results in subsequent systems in mammalian cells. This review describes the primary findings on the nature of ionizing radiation-induced mutagenesis in the N. crassa ad-3 system and the parallel observations made years later in mammalian cells.

Protein adsorption in microengraving immunoassays.

PubMed

Song, Qing

2015-10-16

Microengraving is a novel immunoassay for characterizing multiple protein secretions from single cells. During the immunoassay, characteristic diffusion and kinetic time scales  and  determine the time for molecular diffusion of proteins secreted from the activated single lymphocytes and subsequent binding onto the glass slide surface respectively. Our results demonstrate that molecular diffusion plays important roles in the early stage of protein adsorption dynamics which shifts to a kinetic controlled mechanism in the later stage. Similar dynamic pathways are observed for protein adsorption with significantly fast rates and rapid shifts in transport mechanisms when  is increased a hundred times from 0.313 to 31.3. Theoretical adsorption isotherms follow the trend of experimentally obtained data. Adsorption isotherms indicate that amount of proteins secreted from individual cells and subsequently captured on a clean glass slide surface increases monotonically with time. Our study directly validates that protein secretion rates can be quantified by the microengraving immunoassay. This will enable us to apply microengraving immunoassays to quantify secretion rates from 10⁴-10⁵ single cells in parallel, screen antigen-specific cells with the highest secretion rate for clonal expansion and quantitatively reveal cellular heterogeneity within a small cell sample.

Protein Adsorption in Microengraving Immunoassays

PubMed Central

Song, Qing

2015-01-01

Microengraving is a novel immunoassay forcharacterizing multiple protein secretions from single cells. During the immunoassay, characteristic diffusion and kinetic time scales τD and τK determine the time for molecular diffusion of proteins secreted from the activated single lymphocytes and subsequent binding onto the glass slide surface respectively. Our results demonstrate that molecular diffusion plays important roles in the early stage of protein adsorption dynamics which shifts to a kinetic controlled mechanism in the later stage. Similar dynamic pathways are observed for protein adsorption with significantly fast rates and rapid shifts in transport mechanisms when C0* is increased a hundred times from 0.313 to 31.3. Theoretical adsorption isotherms follow the trend of experimentally obtained data. Adsorption isotherms indicate that amount of proteins secreted from individual cells and subsequently captured on a clean glass slide surface increases monotonically with time. Our study directly validates that protein secretion rates can be quantified by the microengraving immunoassay. This will enable us to apply microengraving immunoassays to quantify secretion rates from 104–105 single cells in parallel, screen antigen-specific cells with the highest secretion rate for clonal expansion and quantitatively reveal cellular heterogeneity within a small cell sample. PMID:26501282

Particles induced surface nanoroughness of titanium surface and its influence on adhesion of osteoblast-like MG-63 cells

NASA Astrophysics Data System (ADS)

Solař, P.; Kylián, O.; Marek, A.; Vandrovcová, M.; Bačáková, L.; Hanuš, J.; Vyskočil, J.; Slavínská, D.; Biederman, H.

2015-01-01

Titanium is one of the most common materials employed for production of implants, which is due to its good biocompatibility. However, the colonization of titanium surface by osteoblast cells may be influenced by its roughness and therefore precise control of roughness of titanium surface as well as identification of its optimal value for growth of cells is of high importance. In this study the nanorough titanium surfaces were prepared on polished disks of TiAlV by two step method of deposition. In the first step TiAlV were coated by nanoparticles generated by gas aggregation sources. Such prepared films of nanoparticles were subsequently covered with a titanium overlayer. Different values of surface roughness in the range 1-100 nm were achieved by variation of the size and number of the nanoparticles. Such prepared surfaces were subsequently used for investigation of influence of roughness of titanium surfaces on the adhesion of human osteoblast-like MG-63 cells. It was found out that 7 days after seeding the highest number of adhering cells was observed for samples with root-mean-square roughness of 30 nm.

Alterations in the Immune Cell Composition in Premalignant Breast Tissue that Precede Breast Cancer Development.

PubMed

Degnim, Amy C; Hoskin, Tanya L; Arshad, Muhammad; Frost, Marlene H; Winham, Stacey J; Brahmbhatt, Rushin A; Pena, Alvaro; Carter, Jodi M; Stallings-Mann, Melody L; Murphy, Linda M; Miller, Erin E; Denison, Lori A; Vachon, Celine M; Knutson, Keith L; Radisky, Derek C; Visscher, Daniel W

2017-07-15

Purpose: Little is known about the role of the immune system in the earliest stages of breast carcinogenesis. We studied quantitative differences in immune cell types between breast tissues from normal donors and those from women with benign breast disease (BBD). Experimental Design: A breast tissue matched case-control study was created from donors to the Susan G. Komen for the Cure Tissue Bank (KTB) and from women diagnosed with BBD at Mayo Clinic (Rochester, MN) who either subsequently developed cancer (BBD cases) or remained cancer-free (BBD controls). Serial tissue sections underwent immunostaining and digital quantification of cell number per mm 2 for CD4 + T cells, CD8 + T cells, CD20 + B cells, and CD68 + macrophages and quantification of positive pixel measure for CD11c (dendritic cells). Results: In 94 age-matched triplets, BBD lobules showed greater densities of CD8 + T cells, CD11c + dendritic cells, CD20 + B cells, and CD68 + macrophages compared with KTB normals. Relative to BBD controls, BBD cases had lower CD20 + cell density ( P = 0.04). Nearly 42% of BBD cases had no CD20 + B cells in evaluated lobules compared with 28% of BBD controls ( P = 0.02). The absence of CD20 + cells versus the presence in all lobules showed an adjusted OR of 5.7 (95% confidence interval, 1.4-23.1) for subsequent breast cancer risk. Conclusions: Elevated infiltration of both innate and adaptive immune effectors in BBD tissues suggests an immunogenic microenvironment. The reduced B-cell infiltration in women with later breast cancer suggests a role for B cells in preventing disease progression and as a possible biomarker for breast cancer risk. Clin Cancer Res; 23(14); 3945-52. ©2017 AACR . ©2017 American Association for Cancer Research.

The In Vitro Response of Tissue Stem Cells to Irradiation With Different Linear Energy Transfers

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

Nagle, Peter W.; Hosper, Nynke A.; Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen

Purpose: A reduction in the dose, irradiated volume, and sensitivity of, in particular, normal tissue stem cells is needed to advance radiation therapy. This could be obtained with the use of particles for radiation therapy. However, the radiation response of normal tissue stem cells is still an enigma. Therefore, in the present study, we developed a model to investigate the in vitro response of stem cells to particle irradiation. Methods and Materials: We used the immortalized human salivary gland (HSG) cell line resembling salivary gland (SG) cells to translate the radiation response in 2-dimensional (2D) to 3-dimensional (3D) conditions. This responsemore » was subsequently translated to the response of SG stem cells (SGSCs). Dispersed single cells were irradiated with photons or carbon ions at different linear energy transfers (LETs; 48.76 ± 2.16, 149.9 ± 10.8, and 189 ± 15 keV/μm). Subsequently, 2D or 3D clonogenicity was determined by counting the colonies or secondary stem cell-derived spheres in Matrigel. γH2AX immunostaining was used to assess DNA double strand break repair. Results: The 2D response of HSG cells showed a similar increase in dose response to increasing higher LET irradiation as other cell lines. The 3D response of HSG cells to increasing LET irradiation was reduced compared with the 2D response. Finally, the response of mouse SGSCs to photons was similar to the 3D response of HSG cells. The response to higher LET irradiation was reduced in the stem cells. Conclusions: Mouse SGSC radiosensitivity seems reduced at higher LET radiation compared with transformed HSG cells. The developed model to assess the radiation response of SGSCs offers novel possibilities to study the radiation response of normal tissue in vitro.« less

The ectopic expression of Pax4 in the mouse pancreas converts progenitor cells into alpha and subsequently beta cells.

PubMed

Collombat, Patrick; Xu, Xiaobo; Ravassard, Philippe; Sosa-Pineda, Beatriz; Dussaud, Sébastien; Billestrup, Nils; Madsen, Ole D; Serup, Palle; Heimberg, Harry; Mansouri, Ahmed

2009-08-07

We have previously reported that the loss of Arx and/or Pax4 gene activity leads to a shift in the fate of the different endocrine cell subtypes in the mouse pancreas, without affecting the total endocrine cell numbers. Here, we conditionally and ectopically express Pax4 using different cell-specific promoters and demonstrate that Pax4 forces endocrine precursor cells, as well as mature alpha cells, to adopt a beta cell destiny. This results in a glucagon deficiency that provokes a compensatory and continuous glucagon+ cell neogenesis requiring the re-expression of the proendocrine gene Ngn3. However, the newly formed alpha cells fail to correct the hypoglucagonemia since they subsequently acquire a beta cell phenotype upon Pax4 ectopic expression. Notably, this cycle of neogenesis and redifferentiation caused by ectopic expression of Pax4 in alpha cells is capable of restoring a functional beta cell mass and curing diabetes in animals that have been chemically depleted of beta cells.

Cyto-adherence of Mycoplasma mycoides subsp. mycoides to bovine lung epithelial cells.

PubMed

Aye, Racheal; Mwirigi, Martin Kiogora; Frey, Joachim; Pilo, Paola; Jores, Joerg; Naessens, Jan

2015-02-07

Mycoplasma mycoides subsp. mycoides (Mmm) is the causative agent of contagious bovine pleuropneumonia (CBPP), a respiratory disease of cattle, whereas the closely related Mycoplasma mycoides subsp. capri (Mmc) is a goat pathogen. Cyto-adherence is a crucial step in host colonization by mycoplasmas and subsequent pathogenesis. The aim of this study was to investigate the interactions between Mmm and mammalian host cells by establishing a cyto-adherence flow cytometric assay and comparing tissue and species specificity of Mmm and Mmc strains. There were little significant differences in the adherence patterns of eight different Mmm strains to adult bovine lung epithelial cells. However, there was statistically significant variation in binding to different host cells types. Highest binding was observed with lung epithelial cells, intermediate binding with endothelial cells and very low binding with fibroblasts, suggesting the presence of effective adherence of Mmm on cells lining the airways of the lung, which is the target organ for this pathogen, possibly by high expression of a specific receptor. However, binding to bovine fetal lung epithelial cells was comparably low; suggesting that the lack of severe pulmonary disease seen in many infected young calves can be explained by reduced expression of a specific receptor. Mmm bound with high efficiency to adult bovine lung cells and less efficiently to calves or goat lung cells. The data show that cyto-adherence of Mmm is species- and tissue- specific confirming its role in colonization of the target host and subsequent infection and development of CBPP.

Amelioration of streptozotocin‑induced pancreatic β cell damage by morin: Involvement of the AMPK‑FOXO3‑catalase signaling pathway.

PubMed

Wang, Ning; Zhang, Jiahui; Qin, Mengting; Yi, Wenjing; Yu, Shuang; Chen, Yi; Guan, Jing; Zhang, Rui

2018-03-01

Pancreatic β cells are sensitive to oxidative stress, which is one of the predominant causes of cell damage and the emergence of diabetes. The identification of effective therapeutic strategies to protect pancreatic cells from oxidative stress has increased interest in the screening of antioxidants from natural products. The present study aimed to investigate the protective effects of morin against streptozotocin (STZ)‑induced cell damage in a rat insulinoma cell line (RINm5F pancreatic β cells) and to identify the underlying mechanisms. The results indicated that morin inhibited the increase in intracellular reactive oxygen species, attenuated the activity of poly (ADP‑ribose) polymerase, restored intracellular nicotinamide adenine dinucleotide levels and reduced the apoptotic cell death of STZ‑treated pancreatic β cells. Treatment with morin significantly upregulated catalase in pancreatic β cells, and ameliorated the STZ‑induced loss of catalase at the genetic, protein and enzymatic level. In further experiments, morin induced the phosphorylation of 5' adenosine monophosphate‑activated protein kinase (AMPK), which subsequently promoted the translocation of forkhead box O3 (FOXO3) to the nucleus. Specific small interfering RNAs (siRNAs) against AMPK and FOXO3 suppressed morin‑induced catalase expression. Furthermore, catalase‑specific siRNA abolished the protective effects of morin against STZ‑stimulated cell death. Taken together, these results indicated that morin protected RINm5F cells from STZ‑induced cell damage by triggering the phosphorylation of AMPK, thus resulting in subsequent activation of FOXO3 and induction of catalase.

An innovative three-dimensional gelatin foam culture system for improved study of glioblastoma stem cell behavior.

PubMed

Yang, Meng-Yin; Chiao, Ming-Tsang; Lee, Hsu-Tung; Chen, Chien-Min; Yang, Yi-Chin; Shen, Chiung-Chyi; Ma, Hsin-I

2015-04-01

Three-dimensional (3-D) tissue engineered constructs provide a platform for examining how the local extracellular matrix contributes to the malignancy of various cancers, including human glioblastoma multiforme. Here, we describe a simple and innovative 3-D culture environment and assess its potential for use with glioblastoma stem cells (GSCs) to examine the diversification inside the cell mass in the 3-D culture system. The dissociated human GSCs were cultured using gelatin foam. These cells were subsequently identified by immunohistochemical staining, reverse transcriptase-polymerase chain reaction, and Western blot assay. We demonstrate that the gelatin foam provides a suitable microenvironment, as a 3-D culture system, for GSCs to maintain their stemness. The gelatin foam culture system contributes a simplified assessment of cell blocks for immunohistochemistry assay. We show that the significant transcription activity of hypoxia and the protein expression of inflammatory responses are detected at the inside of the cell mass in vitro, while robust expression of PROM1/CD133 and hypoxia-induced factor-1 alpha are detected at the xenografted tumor in vivo. We also examine the common clinical trials under this culture platform and characterized a significant difference of drug resistance. The 3-D gelatin foam culture system can provide a more realistic microenvironment through which to study the in vivo behavior of GSCs to evaluate the role that biophysical factors play in the hypoxia, inflammatory responses and subsequent drug resistance. © 2014 Wiley Periodicals, Inc.

Cationic nanocarriers induce cell necrosis through impairment of Na+/K+-ATPase and cause subsequent inflammatory response

PubMed Central

Wei, Xiawei; Shao, Bin; He, Zhiyao; Ye, Tinghong; Luo, Min; Sang, Yaxiong; Liang, Xiao; Wang, Wei; Luo, Shuntao; Yang, Shengyong; Zhang, Shuang; Gong, Changyang; Gou, Maling; Deng, Hongxing; Zhao, Yinglan; Yang, Hanshuo; Deng, Senyi; Zhao, Chengjian; Yang, Li; Qian, Zhiyong; Li, Jiong; Sun, Xun; Han, Jiahuai; Jiang, Chengyu; Wu, Min; Zhang, Zhirong

2015-01-01

Nanocarriers with positive surface charges are known for their toxicity which has limited their clinical applications. The mechanism underlying their toxicity, such as the induction of inflammatory response, remains largely unknown. In the present study we found that injection of cationic nanocarriers, including cationic liposomes, PEI, and chitosan, led to the rapid appearance of necrotic cells. Cell necrosis induced by cationic nanocarriers is dependent on their positive surface charges, but does not require RIP1 and Mlkl. Instead, intracellular Na+ overload was found to accompany the cell death. Depletion of Na+ in culture medium or pretreatment of cells with the Na+/K+-ATPase cation-binding site inhibitor ouabain, protected cells from cell necrosis. Moreover, treatment with cationic nanocarriers inhibited Na+/K+-ATPase activity both in vitro and in vivo. The computational simulation showed that cationic carriers could interact with cation-binding site of Na+/K+-ATPase. Mice pretreated with a small dose of ouabain showed improved survival after injection of a lethal dose of cationic nanocarriers. Further analyses suggest that cell necrosis induced by cationic nanocarriers and the resulting leakage of mitochondrial DNA could trigger severe inflammation in vivo, which is mediated by a pathway involving TLR9 and MyD88 signaling. Taken together, our results reveal a novel mechanism whereby cationic nanocarriers induce acute cell necrosis through the interaction with Na+/K+-ATPase, with the subsequent exposure of mitochondrial damage-associated molecular patterns as a key event that mediates the inflammatory responses. Our study has important implications for evaluating the biocompatibility of nanocarriers and designing better and safer ones for drug delivery. PMID:25613571

Escape is a more common mechanism than avidity reduction for evasion of CD8+ T cell responses in primary human immunodeficiency virus type 1 infection

PubMed Central

2011-01-01

Background CD8+ T cells play an important role in control of viral replication during acute and early human immunodeficiency virus type 1 (HIV-1) infection, contributing to containment of the acute viral burst and establishment of the prognostically-important persisting viral load. Understanding mechanisms that impair CD8+ T cell-mediated control of HIV replication in primary infection is thus of importance. This study addressed the relative extent to which HIV-specific T cell responses are impacted by viral mutational escape versus reduction in response avidity during the first year of infection. Results 18 patients presenting with symptomatic primary HIV-1 infection, most of whom subsequently established moderate-high persisting viral loads, were studied. HIV-specific T cell responses were mapped in each individual and responses to a subset of optimally-defined CD8+ T cell epitopes were followed from acute infection onwards to determine whether they were escaped or declined in avidity over time. During the first year of infection, sequence variation occurred in/around 26/33 epitopes studied (79%). In 82% of cases of intra-epitopic sequence variation, the mutation was confirmed to confer escape, although T cell responses were subsequently expanded to variant sequences in some cases. In contrast, < 10% of responses to index sequence epitopes declined in functional avidity over the same time-frame, and a similar proportion of responses actually exhibited an increase in functional avidity during this period. Conclusions Escape appears to constitute a much more important means of viral evasion of CD8+ T cell responses in acute and early HIV infection than decline in functional avidity of epitope-specific T cells. These findings support the design of vaccines to elicit T cell responses that are difficult for the virus to escape. PMID:21635736

Porcine mast cells infected with H1N1 influenza virus release histamine and inflammatory cytokines and chemokines.

PubMed

Lee, In Hong; Kim, Hyun Soo; Seo, Sang Heui

2017-04-01

Mast cells reside in many tissues, including the lungs, and might play a role in enhancing influenza virus infections in animals. In this study, we cultured porcine mast cells from porcine bone marrow cells with IL-3 and stem cell factor to study the infectivity and activation of the 2009 pandemic H1N1 influenza virus of swine origin. Porcine mast cells were infected with H1N1 influenza virus, without the subsequent production of infectious viruses but were activated, as indicated by the release of histamines. Inflammatory cytokine- and chemokine-encoding genes, including IL-1α, IL-6, CXCL9, CXCL10, and CXCL11, were upregulated in the infected porcine mast cells. Our results suggest that mast cells could be involved in enhancing influenza-virus-mediated disease in infected animals.

Autophagy as a trigger for cell death: autophagic degradation of inhibitor of apoptosis dBruce controls DNA fragmentation during late oogenesis in Drosophila.

PubMed

Nezis, Ioannis P; Shravage, Bhupendra V; Sagona, Antonia P; Johansen, Terje; Baehrecke, Eric H; Stenmark, Harald

2010-11-01

Autophagy has been reported to contribute to cell death, but the underlying mechanisms remain largely unknown and controversial. We have: been studying oogenesis in Drosophila melanogaster as a model system to understand the interplay between autophagy and cell death. Using a novel autophagy reporter we found that autophagy occurs during developmental cell death of nurse cells in late oogenesis. Genetic inhibition: of autophagy-related genes atg1, atg13 and vps34 results in late-stage egg chambers containing persisting nurse cell nuclei without fragmented DNA and attenuation of caspase-3 cleavage. We found that Drosophila inhibitor of apoptosis dBruce is degraded by autophagy and this degradation promotes DNA fragmentation and subsequent nurse cell death. These studies demonstrate that autophagic degradation of an inhibitor: of apoptosis is a novel mechanism of triggering cell death.

Risk of cutaneous squamous cell carcinoma after treatment of basal cell carcinoma with vismodegib.

PubMed

Bhutani, Tina; Abrouk, Michael; Sima, Camelia S; Sadetsky, Natalia; Hou, Jeannie; Caro, Ivor; Chren, Mary-Margaret; Arron, Sarah T

2017-10-01

Vismodegib is a first-in-class agent targeting the hedgehog signaling pathway for treatment of patients with locally advanced basal cell carcinoma (BCC) and metastatic BCC. There have been concerns about the development of squamous cell carcinoma (SCC) in patients treated with this drug. We sought to determine whether treatment with vismodegib is associated with an increase in the risk of cutaneous SCC. In this retrospective cohort study, patients treated with vismodegib as part of phase I and II clinical studies were compared with participants from the University of California, San Francisco, Nonmelanoma Skin Cancer Cohort who received standard therapy for primary BCC. In total, 1675 patients were included in the analysis, and the development of SCC after vismodegib exposure was assessed. The use of vismodegib was not associated with an increased risk of subsequent development of SCC (adjusted hazard ratio, 0.57; 95% confidence interval, 0.28-1.16). Covariates including age, sex, history of previous nonmelanoma skin cancer, and number of visits per year were significantly associated with the development of SCC. A limitation of the study was that a historic control cohort was used as a comparator. Vismodegib was not associated with an increased risk of subsequent SCC when compared with standard surgical treatment of BCC. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Voltage-gated calcium channel autoimmune cerebellar degeneration

PubMed Central

McKasson, Marilyn; Clawson, Susan A.; Hill, Kenneth E.; Wood, Blair; Carlson, Noel; Bromberg, Mark; Greenlee, John E.

2016-01-01

Objectives: To describe response to treatment in a patient with autoantibodies against voltage-gated calcium channels (VGCCs) who presented with autoimmune cerebellar degeneration and subsequently developed Lambert-Eaton myasthenic syndrome (LEMS), and to study the effect of the patient's autoantibodies on Purkinje cells in rat cerebellar slice cultures. Methods: Case report and study of rat cerebellar slice cultures incubated with patient VGCC autoantibodies. Results: A 53-year-old man developed progressive incoordination with ataxic speech. Laboratory evaluation revealed VGCC autoantibodies without other antineuronal autoantibodies. Whole-body PET scans 6 and 12 months after presentation detected no malignancy. The patient improved significantly with IV immunoglobulin G (IgG), prednisone, and mycophenolate mofetil, but worsened after IV IgG was halted secondary to aseptic meningitis. He subsequently developed weakness with electrodiagnostic evidence of LEMS. The patient's IgG bound to Purkinje cells in rat cerebellar slice cultures, followed by neuronal death. Reactivity of the patient's autoantibodies with VGCCs was confirmed by blocking studies with defined VGCC antibodies. Conclusions: Autoimmune cerebellar degeneration associated with VGCC autoantibodies may precede onset of LEMS and may improve with immunosuppressive treatment. Binding of anti-VGCC antibodies to Purkinje cells in cerebellar slice cultures may be followed by cell death. Patients with anti-VGCC autoantibodies may be at risk of irreversible neurologic injury over time, and treatment should be initiated early. PMID:27088118

Determinants of PDT-induced apoptosis

NASA Astrophysics Data System (ADS)

Kessel, David; Luo, Yu; Kim, Hyeong-Reh C.

2000-03-01

Photodynamic therapy can initiate cell death by apoptosis or necrosis. Using agents with known patterns of sub-cellular localization, we examined the correlation between sites of photodamage and the mode of cell death, using murine leukemia cells in vitro. Mitochondrial or mitochondrial/lysosomal photodamage caused the rapid release of cytochrome c. This effect was not temperature sensitive, and could be demonstrated immediately after irradiation of photosensitized cells at 10 degrees C. Subsequent warming to 37 degrees C led to a rapid apoptotic response, consistent with the known ability of cytochrome c to trigger the activation of caspase-3. In contrast, lysosomal or lysosomal/membrane photodamage resulted in the release of cathepsins and other proteolytic enzymes. A subsequent incubation at 37 degrees C resulted in mitochondrial degradation, leading to loss of cytochrome c within 30 min. The apoptotic response was both delayed and incomplete, with many dead cells not exhibiting an apoptotic morphology. The latter outcome was traced to photodamage to procaspase-3, an effect not observed with sensitizers that caused mainly mitochondrial photodamage. Studies in a cell-free system demonstrated that agents with lysosomal and/or membrane targets could bring about photoinactivation of caspase-3. These result are consistent with the proposal that photodynamic therapy can both activate and inactivate components of the apoptotic process.

Tumor dormancy and cell signaling. V. Regrowth of the BCL1 tumor after dormancy is established.

PubMed

Vitetta, E S; Tucker, T F; Racila, E; Huang, Y W; Marches, R; Lane, N; Scheuermann, R H; Street, N E; Watanabe, T; Uhr, J W

1997-06-15

The majority of BALB/c mice immunized with the BCL1 lymphoma-derived idiotype (Id+) IgM and subsequently challenged with BCL1 tumor cells develop a state of tumor dormancy. The vast majority of dormant lymphoma cells are in cell cycle arrest, but there are also residual replicating cells. In the present studies, we attempted to define features of both the dormant lymphoma cells and the host that lead to escape from dormancy. Escape from dormancy occurs at a steady rate over a 2-year period, suggesting that it is a stochastic process. We found that, in the majority of mice, escape was due to the emergence of genetic variants that were no longer susceptible to the anti-Id-mediated induction of dormancy. Ten percent of these variants were Id-; the remainder were Id+ but could grow in the presence of anti-Id antibodies, suggesting that there were mutations in molecules involved in one or more mIg-mediated negative-signaling pathways. In two of five such escapees, alterations in either Syk, HS1, and/or Lyn were observed. In a small percentage of mice, a low titer of circulating anti-Id antibody before tumor challenge correlated with a subsequent, more rapid loss of dormancy.

Akt1 deficiency diminishes skeletal muscle hypertrophy by reducing satellite cell proliferation.

PubMed

Moriya, Nobuki; Miyazaki, Mitsunori

2018-05-01

Skeletal muscle mass is determined by the net dynamic balance between protein synthesis and degradation. Although the Akt/mechanistic target of rapamycin (mTOR)-dependent pathway plays an important role in promoting protein synthesis and subsequent skeletal muscle hypertrophy, the precise molecular regulation of mTOR activity by the upstream protein kinase Akt is largely unknown. In addition, the activation of satellite cells has been indicated as a key regulator of muscle mass. However, the requirement of satellite cells for load-induced skeletal muscle hypertrophy is still under intense debate. In this study, female germline Akt1 knockout (KO) mice were used to examine whether Akt1 deficiency attenuates load-induced skeletal muscle hypertrophy through suppressing mTOR-dependent signaling and satellite cell proliferation. Akt1 KO mice showed a blunted hypertrophic response of skeletal muscle, with a diminished rate of satellite cell proliferation following mechanical overload. In contrast, Akt1 deficiency did not affect the load-induced activation of mTOR signaling and the subsequent enhanced rate of protein synthesis in skeletal muscle. These observations suggest that the load-induced activation of mTOR signaling occurs independently of Akt1 regulation and that Akt1 plays a critical role in regulating satellite cell proliferation during load-induced muscle hypertrophy.

Rationale and design of the German-Speaking Myeloma Multicenter Group (GMMG) trial ReLApsE: a randomized, open, multicenter phase III trial of lenalidomide/dexamethasone versus lenalidomide/dexamethasone plus subsequent autologous stem cell transplantation and lenalidomide maintenance in patients with relapsed multiple myeloma.

PubMed

Baertsch, Marc-Andrea; Schlenzka, Jana; Mai, Elias K; Merz, Maximilian; Hillengaß, Jens; Raab, Marc S; Hose, Dirk; Wuchter, Patrick; Ho, Anthony D; Jauch, Anna; Hielscher, Thomas; Kunz, Christina; Luntz, Steffen; Klein, Stefan; Schmidt-Wolf, Ingo G H; Goerner, Martin; Schmidt-Hieber, Martin; Reimer, Peter; Graeven, Ullrich; Fenk, Roland; Salwender, Hans; Scheid, Christof; Nogai, Axel; Haenel, Mathias; Lindemann, Hans W; Martin, Hans; Noppeney, Richard; Weisel, Katja; Goldschmidt, Hartmut

2016-04-25

Despite novel therapeutic agents, most multiple myeloma (MM) patients eventually relapse. Two large phase III trials have shown significantly improved response rates (RR) of lenalidomide/dexamethasone compared with placebo/dexamethasone in relapsed MM (RMM) patients. These results have led to the approval of lenalidomide for RMM patients and lenalidomide/dexamethasone has since become a widely accepted second-line treatment. Furthermore, in RMM patients consolidation with high-dose chemotherapy plus autologous stem cell transplantation has been shown to significantly increase progression free survival (PFS) as compared to cyclophosphamide in a phase III trial. The randomized prospective ReLApsE trial is designed to evaluate PFS after lenalidomide/dexamethasone induction, high-dose chemotherapy consolidation plus autologous stem cell transplantation and lenalidomide maintenance compared with the well-established lenalidomide/dexamethasone regimen in RMM patients. ReLApsE is a randomized, open, multicenter phase III trial in a planned study population of 282 RMM patients. All patients receive three lenalidomide/dexamethasone cycles and--in absence of available stem cells from earlier harvesting--undergo peripheral blood stem cell mobilization and harvesting. Subsequently, patients in arm A continue on consecutive lenalidomide/dexamethasone cycles, patients in arm B undergo high dose chemotherapy plus autologous stem cell transplantation followed by lenalidomide maintenance until discontinuation criteria are met. Therapeutic response is evaluated after the 3(rd) (arm A + B) and the 5(th) lenalidomide/dexamethasone cycle (arm A) or 2 months after autologous stem cell transplantation (arm B) and every 3 months thereafter (arm A + B). After finishing the study treatment, patients are followed up for survival and subsequent myeloma therapies. The expected trial duration is 6.25 years from first patient in to last patient out. The primary endpoint is PFS, secondary endpoints include overall survival (OS), RR, time to best response and the influence of early versus late salvage high dose chemotherapy plus autologous stem cell transplantation on OS. This phase III trial is designed to evaluate whether high dose chemotherapy plus autologous stem cell transplantation and lenalidomide maintenance after lenalidomide/dexamethasone induction improves PFS compared with the well-established continued lenalidomide/dexamethasone regimen in RMM patients. ISRCTN16345835 (date of registration 2010-08-24).

2D spatially controlled polymer micro patterning for cellular behavior studies

NASA Astrophysics Data System (ADS)

Dinca, V.; Palla-Papavlu, A.; Paraico, I.; Lippert, T.; Wokaun, A.; Dinescu, M.

2011-04-01

A simple and effective method to functionalize glass surfaces that enable polymer micropatterning and subsequent spatially controlled adhesion of cells is reported in this paper. The method involves the application of laser induced forward transfer (LIFT) to achieve polymer patterning in a single step onto cell repellent substrates (i.e. polyethyleneglycol (PEG)). This approach was used to produce micron-size polyethyleneimine (PEI)-patterns alternating with cell-repellent areas. The focus of this work is the ability of SH-SY5Y human neuroblastoma cells to orient, migrate, and produce organized cellular arrangements on laser generated PEI patterns.

Age-related changes in cell localization and proliferation in lymph nodes and spleen after antigenic stimulation.

PubMed Central

Ansell, J D; McDougall, C M; Micklem, H S; Inchley, C J

1980-01-01

Antigen-dependent localization of 51Cr-labelled lymphocytes, and the subsequent uptake of IUdR into lymphoid organs has been studied as a function of age. Measures of cell localization indicated that while old age can alter the patterns of entry of lymphocytes into lymph nodes and spleen, these changes are variable and probably not sufficient alone to explain decreased primary antibody responses in old animals. Proliferation of cells, however, was consistently affected in both organs and this phenomenon is discussed in terms of abnormal T-cell function. PMID:7429546

Next Generation Mesenchymal Stem Cell (MSC)–Based Cartilage Repair Using Scaffold-Free Tissue Engineered Constructs Generated with Synovial Mesenchymal Stem Cells

PubMed Central

Shimomura, Kazunori; Ando, Wataru; Moriguchi, Yu; Sugita, Norihiko; Yasui, Yukihiko; Koizumi, Kota; Fujie, Hiromichi; Hart, David A.; Yoshikawa, Hideki

2015-01-01

Because of its limited healing capacity, treatments for articular cartilage injuries are still challenging. Since the first report by Brittberg, autologous chondrocyte implantation has been extensively studied. Recently, as an alternative for chondrocyte-based therapy, mesenchymal stem cell–based therapy has received considerable research attention because of the relative ease in handling for tissue harvest, and subsequent cell expansion and differentiation. This review summarizes latest development of stem cell therapies in cartilage repair with special attention to scaffold-free approaches. PMID:27340513

The effects of platelet lysate on maturation, fertilization and embryo development of NMRI mouse oocytes at germinal vesicle stage.

PubMed

Pazoki, Hassan; Eimani, Hussein; Farokhi, Farah; Shahverdi, Abdol-Hossein; Tahaei, Leila Sadat

2016-04-01

Improving in vitro maturation could increase the rate of pregnancy from oocytes matured in vitro. Consequently, patients will be prevented from using gonadotropin with its related side effects. In this study, the maturation medium was enriched by platelet lysate (PL), then maturation and subsequent developments were monitored. Oocytes at germinal vesicle stage with cumulus cells (cumulus-oocyte complex) and without cumulus cells (denuded oocytes) were obtained from mature female mice. The maturation medium was enriched by 5 and 10 % PL and 5 % PL + 5 % fetal bovine serum (FBS) as experimental groups; the control groups' media consisted of 5 and 10 % FBS. After 18 h, the matured oocytes were collected and, after fertilization, subsequent development was monitored. The rates of maturation, fertilization and 2-cell embryo development for the denuded oocyte groups in experimental media 5 % PL and 5 % PL + 5 % FBS were significantly higher than those of the control groups ( P < 0.05), while the results for the cumulus-oocyte complex groups were similar between the experimental groups and control groups. The results of this study indicated that platelet lysate could improve the maturation rate in the absence of granulosa cells compared to media with FBS. This extract also had positive effects on fertilization and embryo development.

Specifying and protecting germ cell fate

PubMed Central

Strome, Susan; Updike, Dustin

2015-01-01

Germ cells are the special cells in the body that undergo meiosis to generate gametes and subsequently entire new organisms after fertilization, a process that continues generation after generation. Recent studies have expanded our understanding of the factors and mechanisms that specify germ cell fate, including the partitioning of maternally supplied ‘germ plasm’, inheritance of epigenetic memory and expression of transcription factors crucial for primordial germ cell (PGC) development. Even after PGCs are specified, germline fate is labile and thus requires protective mechanisms, such as global transcriptional repression, chromatin state alteration and translation of only germline-appropriate transcripts. Findings from diverse species continue to provide insights into the shared and divergent needs of these special reproductive cells. PMID:26122616

Effects of SPORL and dilute acid pretreatment on substrate morphology, cell physical and chemical wall structures, and subsequent enzymatic hydrolysis of lodgepole pine

Treesearch

Xinping Li; Xiaolin Luo; Kecheng Li; J.Y. Zhu; J. Dennis Fougere; Kimberley Clarke

2012-01-01

The effects of pretreatment by dilute acid and sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) on substrate morphology, cell wall physical and chemical structures, along with the subsequent enzymatic hydrolysis of lodgepole pine substrate were investigated. FE-SEM and TEM images of substrate structural morphological changes showed that SPORL...

Metabolic regulation of magnolol on the nuclear receptor, liver X receptor.

PubMed

Xie, N A; Hu, Chunyang; Guo, Anran; Liang, Hao; DU, Pengcheng; Yin, Guotian

2015-05-01

The aim of the present study was to investigate whether magnolol, the essential component of the traditional Chinese medicine, Magnolia officinalis , can pass through liver X receptor α (LXRα), to subsequently play an important role in the lipid metabolic balance. Using a HepG2 human hepatoma cell line, mammalian cellular one-hybridization and mammalian cell transcriptional activation experiments were performed to detect the combination degree of magnolol at different concentrations with LXRα, and assess the transcriptional activity. In addition, using a THP-1 human monocytic cell line, quantitative polymerase chain reaction was performed to assess the effect on the expression levels of downstream genes. Magnolol was shown to dose-dependently combine with LXRα, and subsequently regulate the transcriptional activity of LXRα. In addition, magnolol was found to adjust the expression of associated LXRα downstream genes in the macrophages. In conclusion, magnolol was demonstrated to affect LXRα, which may outline a new molecular mechanism through which magnolol exerts a lipid-lowering function.

A simple, xeno-free method for oligodendrocyte generation from human neural stem cells derived from umbilical cord: engagement of gelatinases in cell commitment and differentiation.

PubMed

Sypecka, Joanna; Ziemka-Nalecz, Małgorzata; Dragun-Szymczak, Patrycja; Zalewska, Teresa

2017-05-01

Oligodendrocyte progenitors (OPCs) are ranked among the most likely candidates for cell-based strategies aimed at treating neurodegenerative diseases accompanied by dys/demyelination of the central nervous system (CNS). In this regard, different sources of stem cells are being tested to elaborate xeno-free protocols for efficient generation of OPCs for clinical applications. In the present study, neural stem cells of human umbilical cord blood (HUCB-NSCs) have been used to derive OPCs and subsequently to differentiate them into mature, GalC-expressing oligodendrocytes. Applied components of the extracellular matrix (ECM) and the analogues of physiological substances known to increase glial commitment of neural stem cells have been shown to significantly increase the yield of the resulting OPC fraction. The efficiency of ECM components in promoting oligodendrocyte commitment and differentiation prompted us to investigate the potential role of gelatinases in those processes. Subsequently, endogenous and ECM metalloproteinases (MMPs) activity has been compared with that detected in primary cultures of rat oligodendrocytes in vitro, as well as in rat brains in vivo. The data indicate that gelatinases are engaged in gliogenesis both in vitro and in vivo, although differently, which presumably results from distinct extracellular conditions. In conclusion, the study presents an efficient xeno-free method of deriving oligodendrocyte from HUCB-NSCs and analyses the engagement of MMP-2/MMP-9 in the processes of cell commitment and maturation. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Recapitulation of spinal motor neuron-specific disease phenotypes in a human cell model of spinal muscular atrophy

PubMed Central

Wang, Zhi-Bo; Zhang, Xiaoqing; Li, Xue-Jun

2013-01-01

Establishing human cell models of spinal muscular atrophy (SMA) to mimic motor neuron-specific phenotypes holds the key to understanding the pathogenesis of this devastating disease. Here, we developed a closely representative cell model of SMA by knocking down the disease-determining gene, survival motor neuron (SMN), in human embryonic stem cells (hESCs). Our study with this cell model demonstrated that knocking down of SMN does not interfere with neural induction or the initial specification of spinal motor neurons. Notably, the axonal outgrowth of spinal motor neurons was significantly impaired and these disease-mimicking neurons subsequently degenerated. Furthermore, these disease phenotypes were caused by SMN-full length (SMN-FL) but not SMN-Δ7 (lacking exon 7) knockdown, and were specific to spinal motor neurons. Restoring the expression of SMN-FL completely ameliorated all of the disease phenotypes, including specific axonal defects and motor neuron loss. Finally, knockdown of SMN-FL led to excessive mitochondrial oxidative stress in human motor neuron progenitors. The involvement of oxidative stress in the degeneration of spinal motor neurons in the SMA cell model was further confirmed by the administration of N-acetylcysteine, a potent antioxidant, which prevented disease-related apoptosis and subsequent motor neuron death. Thus, we report here the successful establishment of an hESC-based SMA model, which exhibits disease gene isoform specificity, cell type specificity, and phenotype reversibility. Our model provides a unique paradigm for studying how motor neurons specifically degenerate and highlights the potential importance of antioxidants for the treatment of SMA. PMID:23208423

Visualizing Vpr-Induced G2 Arrest and Apoptosis

PubMed Central

Murakami, Tomoyuki; Aida, Yoko

2014-01-01

Vpr is an accessory protein of human immunodeficiency virus type 1 (HIV-1) with multiple functions. The induction of G2 arrest by Vpr plays a particularly important role in efficient viral replication because the transcriptional activity of the HIV-1 long terminal repeat is most active in G2 phase. The regulation of apoptosis by Vpr is also important for immune suppression and pathogenesis during HIV infection. However, it is not known whether Vpr-induced apoptosis depends on the ability of Vpr to induce G2 arrest, and the dynamics of Vpr-induced G2 arrest and apoptosis have not been visualized. We performed time-lapse imaging to examine the temporal relationship between Vpr-induced G2 arrest and apoptosis using HeLa cells containing the fluorescent ubiquitination-based cell cycle indicator2 (Fucci2). The dynamics of G2 arrest and subsequent long-term mitotic cell rounding in cells transfected with the Vpr-expression vector were visualized. These cells underwent nuclear mis-segregation after prolonged mitotic processes and then entered G1 phase. Some cells subsequently displayed evidence of apoptosis after prolonged mitotic processes and nuclear mis-segregation. Interestingly, Vpr-induced apoptosis was seldom observed in S or G2 phase. Likewise, visualization of synchronized HeLa/Fucci2 cells infected with an adenoviral vector expressing Vpr clearly showed that Vpr arrests the cell cycle at G2 phase, but does not induce apoptosis at S or G2 phase. Furthermore, time-lapse imaging of HeLa/Fucci2 cells expressing SCAT3.1, a caspase-3-sensitive fusion protein, clearly demonstrated that Vpr induces caspase-3-dependent apoptosis. Finally, to examine whether the effects of Vpr on G2 arrest and apoptosis were reversible, we performed live-cell imaging of a destabilizing domain fusion Vpr, which enabled rapid stabilization and destabilization by Shield1. The effects of Vpr on G2 arrest and subsequent apoptosis were reversible. This study is the first to characterize the dynamics of the morphological changes that occur during Vpr-induced G2 arrest and apoptosis. PMID:24466265

Cancer stem cell markers in patterning differentiation and in prognosis of oral squamous cell carcinoma.

PubMed

Mohanta, Simple; Siddappa, Gangotri; Valiyaveedan, Sindhu Govindan; Dodda Thimmasandra Ramanjanappa, Ravindra; Das, Debashish; Pandian, Ramanan; Khora, Samanta Sekhar; Kuriakose, Moni Abraham; Suresh, Amritha

2017-06-01

Differentiation is a major histological parameter determining tumor aggressiveness and prognosis of the patient; cancer stem cells with their slow dividing and undifferentiated nature might be one of the factors determining the same. This study aims to correlate cancer stem cell markers (CD44 and CD147) with tumor differentiation and evaluate their subsequent effect on prognosis. Immunohistochemical analysis in treatment naïve oral cancer patients (n = 53) indicated that the expression of CD147 was associated with poorly differentiated squamous cell carcinoma and moderately differentiated squamous cell carcinoma (p < 0.01). Furthermore, co-expression analysis showed that 45% each of moderately differentiated squamous cell carcinoma and poorly differentiated squamous cell carcinoma patients were CD44 high /CD147 high as compared to only 10% of patients with well-differentiated squamous cell carcinoma. A three-way analysis indicated that differentiation correlated with recurrence and survival (p < 0.05) in only the patients with CD44 high /CD147 high cohort. Subsequently, relevance of these cancer stem cell markers in patterning the differentiation characteristics was evaluated in oral squamous cell carcinoma cell lines originating from different grades of oral cancer. Flowcytometry-based analysis indicated an increase in CD44 + /CD147 + cells in cell lines of poorly differentiated squamous cell carcinoma (94.35 ± 1.14%, p < 0.001) and moderately differentiated squamous cell carcinoma origin (93.49 ± 0.47%, p < 0.001) as compared to cell line of well-differentiated squamous cell carcinoma origin (23.12% ± 0.49%). Expression profiling indicated higher expression of cancer stem cell and epithelial-mesenchymal transition markers in SCC029B (poorly differentiated squamous cell carcinoma originated; p ≤ 0.001), which was further translated into increased spheroid formation, migration, and invasion (p < 0.001) as compared to cell line of well-differentiated squamous cell carcinoma origin. This study suggests that CD44 and CD147 together improve the prognostic efficacy of tumor differentiation; in vitro results further point out that these markers might be determinant of differentiation characteristics, imparting properties of increased self-renewal, migration, and invasion.

Cisplatin toxicity reduced in human cultured renal tubular cells by oxygen pretreatment.

PubMed

Kaeidi, Ayat; Rasoulian, Bahram; Hajializadeh, Zahra; Pourkhodadad, Soheila; Rezaei, Maryam

2013-01-01

Cisplatin is an effective and widely used chemotherapy agent and its side effects, particularly nephrotoxicity, limit its usage and related platinum-based drugs. Cisplatin nephrotoxicity is mainly due to extremely increase in reactive oxygen species (ROS) generation leading to kidney tubular cell death. Preconditioning with oxidative stress has been demonstrated to stimulate the cellular adaptation to subsequent severe oxidative stress. Short term oxygen pre-exposure as a mild oxidative stress may enhance some endogenous defense mechanisms, so its effect on Cisplatin induced cell death was investigated in present research. We studied the effects of hyperoxic environment pre-exposure on Cisplatin toxicity in an in-vitro model of cultured human embryonic tubular epithelial cells (AD293). Viability of AD293 cells, as evaluated by MTT-assay, was affected by Cisplatin in a time (1-4 h) dependent model. Biochemical markers of cell apoptosis were evaluated using immunoblotting. Pretreatment with nearly pure oxygen (≥90%) for 2 h significantly reduced the level of cell damage. Activated caspase 3 and Bax/Bcl-2 ratio were significantly increased in Cisplatin-treated cells. Oxygen pretreatment inhibited caspase 3 activation and decreased Bax/Bcl-2 ratio. Oxygen pre-treatment itself not showed any cytotoxicity in exposure times up to 3 h. Our data indicate that hyperoxic preconditioning reduces Cisplatin toxicity in cultured human tubular epithelial cells. The exact mechanism of protection is unclear, though enhancement of some endogenous defense mechanisms and subsequently scavenging of free oxygen radicals may play an important role.

Ultra-localized single cell electroporation using silicon nanowires.

PubMed

Jokilaakso, Nima; Salm, Eric; Chen, Aaron; Millet, Larry; Guevara, Carlos Duarte; Dorvel, Brian; Reddy, Bobby; Karlstrom, Amelie Eriksson; Chen, Yu; Ji, Hongmiao; Chen, Yu; Sooryakumar, Ratnasingham; Bashir, Rashid

2013-02-07

Analysis of cell-to-cell variation can further the understanding of intracellular processes and the role of individual cell function within a larger cell population. The ability to precisely lyse single cells can be used to release cellular components to resolve cellular heterogeneity that might be obscured when whole populations are examined. We report a method to position and lyse individual cells on silicon nanowire and nanoribbon biological field effect transistors. In this study, HT-29 cancer cells were positioned on top of transistors by manipulating magnetic beads using external magnetic fields. Ultra-rapid cell lysis was subsequently performed by applying 600-900 mV(pp) at 10 MHz for as little as 2 ms across the transistor channel and the bulk substrate. We show that the fringing electric field at the device surface disrupts the cell membrane, leading to lysis from irreversible electroporation. This methodology allows rapid and simple single cell lysis and analysis with potential applications in medical diagnostics, proteome analysis and developmental biology studies.

Cytocompatibility of polyethylene grafted with triethylenetetramine functionalized carbon nanoparticles

NASA Astrophysics Data System (ADS)

Žáková, Pavlína; Slepičková Kasálková, Nikola; Slepička, Petr; Kolská, Zdeňka; Karpíšková, Jana; Stibor, Ivan; Švorčík, Václav

2017-11-01

Various carbon nanostructures are widely researched as scaffolds for tissue engineering. We evaluated the surface properties and cell-substrate interactions of carbon nanoparticles functionalized with triethylenetetramine (CNPs) grafted polymer film. Two forms of polyethylene (HDPE, LDPE) were treated in an inert argon plasma discharge and, subsequently, grafted with CNPs. The surface properties were studied using multiple methods, including Raman spectroscopy, goniometry, atomic force microscopy, X-ray photoelectron spectroscopy and electrokinetic analysis. Cell-substrate interactions were determined in vitro by studying adhesion, proliferation and viability of vascular smooth muscle cells (VSMCs) from the aorta of a rat. Cell-substrate interactions on pristine and modified substrates were compared to standard tissue culture polystyrene. Our results show that CNPs affect surface morphology and wettability and therefore adhesion, proliferation and viability of cultured muscle cells.

Photoaffinity-labeling and fluorescence-distribution studies of gonadotropin-releasing hormone receptors in ovarian granulosa cells.

PubMed Central

Hazum, E; Nimrod, A

1982-01-01

Photoaffinity labeling of rat ovarian granulosa cells and membrane preparations with a bioactive photoaffinity derivative of gonadotropin-releasing hormone resulted in identification of two specific components with apparent molecular weights of 60,000 and 54,000. Fluorescent visualization of gonadotropin-releasing hormone receptors in these cells, by using a bioactive rhodamine derivative of the hormone, indicated that the fluorescently labeled receptors were initially distributed uniformly on the cell surface and then formed patches that subsequently internalized (at 37 degrees C) into endocytic vesicles. These processes were dependent on specific binding sites for the rhodamine-labeled peptide on the granulosa cells. These studies may provide an experimental basis for understanding the molecular events involved in the action of the hormone in the ovary. Images PMID:6281784

The IDO1 selective inhibitor epacadostat enhances dendritic cell immunogenicity and lytic ability of tumor antigen-specific T cells.

PubMed

Jochems, Caroline; Fantini, Massimo; Fernando, Romaine I; Kwilas, Anna R; Donahue, Renee N; Lepone, Lauren M; Grenga, Italia; Kim, Young-Seung; Brechbiel, Martin W; Gulley, James L; Madan, Ravi A; Heery, Christopher R; Hodge, James W; Newton, Robert; Schlom, Jeffrey; Tsang, Kwong Y

2016-06-21

Epacadostat is a novel inhibitor of indoleamine-2,3-dioxygenase-1 (IDO1) that suppresses systemic tryptophan catabolism and is currently being evaluated in ongoing clinical trials. We investigated the effects of epacadostat on (a) human dendritic cells (DCs) with respect to maturation and ability to activate human tumor antigen-specific cytotoxic T-cell (CTL) lines, and subsequent T-cell lysis of tumor cells, (b) human regulatory T cells (Tregs), and (c) human peripheral blood mononuclear cells (PBMCs) in vitro. Simultaneous treatment with epacadostat and IFN-γ plus lipopolysaccharide (LPS) did not change the phenotype of matured human DCs, and as expected decreased the tryptophan breakdown and kynurenine production. Peptide-specific T-cell lines stimulated with DCs pulsed with peptide produced significantly more IFN-γ, TNFα, GM-CSF and IL-8 if the DCs were treated with epacadostat. These T cells also displayed higher levels of tumor cell lysis on a per cell basis. Epacadostat also significantly decreased Treg proliferation induced by IDO production from IFN-γ plus LPS matured human DCs, although the Treg phenotype did not change. Multicolor flow cytometry was performed on human PBMCs treated with epacadostat; analysis of 123 discrete immune cell subsets revealed no changes in major immune cell types, an increase in activated CD83+ conventional DCs, and a decrease in immature activated Tim3+ NK cells. These studies show for the first time several effects of epacadostat on human DCs, and subsequent effects on CTL and Tregs, and provide a rationale as to how epacadostat could potentially increase the efficacy of immunotherapeutics, including cancer vaccines.

Protective Effects of N-Acetyl Cysteine against Diesel Exhaust Particles-Induced Intracellular ROS Generates Pro-Inflammatory Cytokines to Mediate the Vascular Permeability of Capillary-Like Endothelial Tubes

PubMed Central

Tseng, Chia-Yi; Chang, Jing-Fen; Wang, Jhih-Syuan; Chang, Yu-Jung; Gordon, Marion K.; Chao, Ming-Wei

2015-01-01

Exposure to diesel exhaust particles (DEP) is associated with pulmonary and cardiovascular diseases. Previous studies using in vitro endothelial tubes as a simplified model of capillaries have found that DEP-induced ROS increase vascular permeability with rearrangement or internalization of adherens junctional VE-cadherin away from the plasma membrane. This allows DEPs to penetrate into the cell and capillary lumen. In addition, pro-inflammatory cytokines are up-regulated and mediate vascular permeability in response to DEP. However, the mechanisms through which these DEP-induced pro-inflammatory cytokines increase vascular permeability remain unknown. Hence, we examined the ability of DEP to induce permeability of human umbilical vein endothelial cell tube cells to investigate these mechanisms. Furthermore, supplementation with NAC reduces ROS production following exposure to DEP. HUVEC tube cells contributed to a pro-inflammatory response to DEP-induced intracellular ROS generation. Endothelial oxidative stress induced the release of TNF-α and IL-6 from tube cells, subsequently stimulating the secretion of VEGF-A independent of HO-1. Our data suggests that DEP-induced intracellular ROS and release of the pro-inflammatory cytokines TNF- α and IL-6, which would contribute to VEGF-A secretion and disrupt cell-cell borders and increase vasculature permeability. Addition of NAC suppresses DEP-induced ROS efficiently and reduces subsequent damages by increasing endogenous glutathione. PMID:26148005

Anti-adhesion Property of the Potential Probiotic Strain Lactobacillus fermentum 8711 Against Methicillin-Resistant Staphylococcus aureus (MRSA).

PubMed

Jayashree, Sathyanarayanan; Karthikeyan, Raman; Nithyalakshmi, Sampath; Ranjani, Jothi; Gunasekaran, Paramasamy; Rajendhran, Jeyaprakash

2018-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug-resistant pathogen and one of the leading causes of nosocomial infection worldwide. Probiotic bacteria play a significant role in preventive or therapeutic interventions of gastrointestinal infections in human as well as animals. In this study, we have investigated the adhesion property of the probiotic strain Lactobacillus fermentum MTCC 8711 and its ability to prevent the adhesion of MRSA to human colon adenocarcinoma cells, Caco-2. We have shown that L. fermentum could efficiently adhere to the Caco-2 cells. Also, we have shown that L. fermentum significantly reduced MRSA adhesion to Caco-2 cells. Three types of experiments were performed to assess the anti-adhesion property of L. fermentum against MRSA. Inhibition (Caco-2 cells were pre-treated with L. fermentum , and subsequently MRSA was added), competition (both L. fermentum and MRSA were added to Caco-2 cells simultaneously), and displacement or exclusion (Caco-2 cells were pre-treated with MRSA, and subsequently L. fermentum was added). In all three experiments, adhesion of MRSA was significantly reduced. Interestingly, L. fermentum could efficiently displace the adhered MRSA, and hence this probiotic can be used for therapeutic applications also. In cytotoxicity assay, we found that L. fermentum per se was not cytotoxic, and also significantly reduced the MRSA-induced cytotoxicity. The protective effect occurred without affecting Caco-2 cell morphology and viability.

The Effect of Laser Irradiation on Adipose Derived Stem Cell Proliferation and Differentiation

NASA Astrophysics Data System (ADS)

Abrahamse, H.; de Villiers, J.; Mvula, B.

2009-06-01

There are two fundamental types of stem cells: Embryonic Stem cells and Adult Stem cells. Adult Stem cells have a more restricted potential and can usually differentiate into a few different cell types. In the body these cells facilitate the replacement or repair of damaged or diseased cells in organs. Low intensity laser irradiation was shown to increase stem cell migration and stimulate proliferation and it is thought that treatment of these cells with laser irradiation may increase the stem cell harvest and have a positive effect on the viability and proliferation. Our research is aimed at determining the effect of laser irradiation on differentiation of Adipose Derived Stem Cells (ADSCs) into different cell types using a diode laser with a wavelength of 636 nm and at 5 J/cm2. Confirmation of stem cell characteristics and well as subsequent differentiation were assessed using Western blot analysis and cellular morphology supported by fluorescent live cell imaging. Functionality of subsequent differentiated cells was confirmed by measuring adenosine triphosphate (ATP) production and cell viability.

Delayed rectifier K channels contribute to contrast adaptation in mammalian retinal ganglion cells

PubMed Central

Weick, Michael; Demb, Jonathan B.

2011-01-01

SUMMARY Retinal ganglion cells adapt by reducing their sensitivity during periods of high contrast. Contrast adaptation in the firing response depends on both presynaptic and intrinsic mechanisms. Here, we investigated intrinsic mechanisms for contrast adaptation in OFF Alpha ganglion cells in the in vitro guinea pig retina. Using either visual stimulation or current injection, we show that brief depolarization evoked spiking and suppressed firing during subsequent depolarization. The suppression could be explained by Na channel inactivation, as shown in salamander cells. However, brief hyperpolarization in the physiological range (5–10 mV) also suppressed firing during subsequent depolarization. This suppression was sensitive selectively to blockers of delayed-rectifier K channels (KDR). Somatic membrane patches showed TEA-sensitive KDR currents with activation near −25 mV and removal of inactivation at voltages negative to Vrest. Brief periods of hyperpolarization apparently remove KDR inactivation and thereby increase the channel pool available to suppress excitability during subsequent depolarization. PMID:21745646

Delayed-rectifier K channels contribute to contrast adaptation in mammalian retinal ganglion cells.

PubMed

Weick, Michael; Demb, Jonathan B

2011-07-14

Retinal ganglion cells adapt by reducing their sensitivity during periods of high contrast. Contrast adaptation in the firing response depends on both presynaptic and intrinsic mechanisms. Here, we investigated intrinsic mechanisms for contrast adaptation in OFF Alpha ganglion cells in the in vitro guinea pig retina. Using either visual stimulation or current injection, we show that brief depolarization evoked spiking and suppressed firing during subsequent depolarization. The suppression could be explained by Na channel inactivation, as shown in salamander cells. However, brief hyperpolarization in the physiological range (5-10 mV) also suppressed firing during subsequent depolarization. This suppression was selectively sensitive to blockers of delayed-rectifier K channels (K(DR)). In somatic membrane patches, we observed tetraethylammonium-sensitive K(DR) currents that activated near -25 mV. Recovery from inactivation occurred at potentials hyperpolarized to V(rest). Brief periods of hyperpolarization apparently remove K(DR) inactivation and thereby increase the channel pool available to suppress excitability during subsequent depolarization. Copyright © 2011 Elsevier Inc. All rights reserved.

Capture and On-chip analysis of Melanoma Cells Using Tunable Surface Shear forces

NASA Astrophysics Data System (ADS)

Tsao, Simon Chang-Hao; Vaidyanathan, Ramanathan; Dey, Shuvashis; Carrascosa, Laura G.; Christophi, Christopher; Cebon, Jonathan; Shiddiky, Muhammad J. A.; Behren, Andreas; Trau, Matt

2016-01-01

With new systemic therapies becoming available for metastatic melanoma such as BRAF and PD-1 inhibitors, there is an increasing demand for methods to assist with treatment selection and response monitoring. Quantification and characterisation of circulating melanoma cells (CMCs) has been regarded as an excellent non-invasive candidate but a sensitive and efficient tool to do these is lacking. Herein we demonstrate a microfluidic approach for melanoma cell capture and subsequent on-chip evaluation of BRAF mutation status. Our approach utilizes a recently discovered alternating current electrohydrodynamic (AC-EHD)-induced surface shear forces, referred to as nanoshearing. A key feature of nanoshearing is the ability to agitate fluid to encourage contact with surface-bound antibody for the cell capture whilst removing nonspecific cells from the surface. By adjusting the AC-EHD force to match the binding affinity of antibodies against the melanoma-associated chondroitin sulphate proteoglycan (MCSP), a commonly expressed melanoma antigen, this platform achieved an average recovery of 84.7% from biological samples. Subsequent staining with anti-BRAFV600E specific antibody enabled on-chip evaluation of BRAFV600E mutation status in melanoma cells. We believe that the ability of nanoshearing-based capture to enumerate melanoma cells and subsequent on-chip characterisation has the potential as a rapid screening tool while making treatment decisions.

Surface free energy predominates in cell adhesion to hydroxyapatite through wettability.

PubMed

Nakamura, Miho; Hori, Naoko; Ando, Hiroshi; Namba, Saki; Toyama, Takeshi; Nishimiya, Nobuyuki; Yamashita, Kimihiro

2016-05-01

The initial adhesion of cells to biomaterials is critical in the regulation of subsequent cell behaviors. The purpose of this study was to investigate a mechanism through which the surface wettability of biomaterials can be improved and determine the effects of biomaterial surface characteristics on cellular behaviors. We investigated the surface characteristics of various types of hydroxyapatite after sintering in different atmospheres and examined the effects of various surface characteristics on cell adhesion to study cell-biomaterial interactions. Sintering atmosphere affects the polarization capacity of hydroxyapatite by changing hydroxide ion content and grain size. Compared with hydroxyapatite sintered in air, hydroxyapatite sintered in saturated water vapor had a higher polarization capacity that increased surface free energy and improved wettability, which in turn accelerated cell adhesion. We determined the optimal conditions of hydroxyapatite polarization for the improvement of surface wettability and acceleration of cell adhesion. Copyright © 2016 Elsevier B.V. All rights reserved.

Host-Cell Survival and Death During Chlamydia Infection

PubMed Central

Ying, Songmin; Pettengill, Matthew; Ojcius, David M.; Häcker, Georg

2008-01-01

Different Chlamydia trachomatis strains are responsible for prevalent bacterial sexually-transmitted disease and represent the leading cause of preventable blindness worldwide. Factors that predispose individuals to disease and mechanisms by which chlamydiae cause inflammation and tissue damage remain unclear. Results from recent studies indicate that prolonged survival and subsequent death of infected cells and their effect on immune effector cells during chlamydial infection may be important in determining the outcome. Survival of infected cells is favored at early times of infection through inhibition of the mitochondrial pathway of apoptosis. Death at later times displays features of both apoptosis and necrosis, but pro-apoptotic caspases are not involved. Most studies on chlamydial modulation of host-cell death until now have been performed in cell lines. The consequences for pathogenesis and the immune response will require animal models of chlamydial infection, preferably mice with targeted deletions of genes that play a role in cell survival and death. PMID:18843378

Initiation of oncogenic transformation in human mammary epithelial cells by charged particles

NASA Technical Reports Server (NTRS)

Yang, T. C.; Georgy, K. A.; Craise, L. M.; Durante, M.

1997-01-01

Experimental studies have shown that high linear-energy transfer (LET) charged particles can be more effective than x-rays and gamma-rays in inducing oncogenic transformation in cultured cells and tumors in animals. Based on these results, experiments were designed and performed with an immortal human mammary epithelial cell line (H184B5), and several clones transformed by heavy ions were obtained. Cell fusion experiments were subsequently done, and results indicate that the transforming gene(s) is recessive. Chromosome analysis with fluorescence in situ hybridization (FISH) techniques also showed additional translocations in transformed human mammary epithelial cells. In addition, studies with these cell lines indicate that heavy ions can effectively induce deletion, break, and dicentrics. Deletion of tumor suppressor gene(s) and/or formation of translocation through DNA double strand breaks is a likely mechanism for the initiation of oncogenic transformation in human mammary epithelial cells.

The application of Dow Chemical's perfluorinated membranes in proton-exchange membrane fuel cells

NASA Technical Reports Server (NTRS)

Eisman, G. A.

1989-01-01

Dow Chemical's research activities in fuel cell devices revolves around the development and subsequent investigation of the perfluorinated inomeric membrane separator useful in proton-exchange membrane systems. Work is currently focusing on studying the effects of equivalent weight, thickness, water of hydration, pretreatment procedures, as well as the degree of water management required for a given membrane separator in the cell. The presentation will include details of certain aspects of the above as well as some of the requirements for high and low power generation.

Hybrid Organic/Inorganic Nanocomposites for Photovoltaic Cells

PubMed Central

Liu, Ruchuan

2014-01-01

Inorganic/organic hybrid solar cells have attracted a lot of interest due to their potential in combining the advantages of both components. To understand the key issues in association with photoinduced charge separation/transportation processes and to improve overall power conversion efficiency, various combinations with nanostructures of hybrid systems have been investigated. Here, we briefly review the structures of hybrid nanocomposites studied so far, and attempt to associate the power conversion efficiency with these nanostructures. Subsequently, we are then able to summarize the factors for optimizing the performance of inorganic/organic hybrid solar cells. PMID:28788591

T cell-depleted splenocytes from mice pre-immunized with neuroantigen in incomplete Freund's adjuvant involved in protection from experimental autoimmune encephalomyelitis.

PubMed

Zheng, Hui; Zhang, Han; Liu, Feng; Qi, Yuanyuan; Jiang, Hong

2014-01-01

Mice immunized with neuroantigens in incomplete Freund's adjuvant (IFA) are resistant to subsequent induction of experimental autoimmune encephalomyelitis (EAE). The mechanisms involved in this protection are complex. Studies on relevant CD4(+) or CD8(+) T cells, including effective and regulatory T cells, have been performed by others. In this work, the effects of CD4(-)-, CD8(-)- splenocytes on protection from EAE in C57BL/6 mice which were immunized with myelin oligodendrocyte glycoprotein 35-55 (MOG)35-55 in IFA were evaluated. We observed that MOG-reactive CD4(+) T cells failed to be activated and proliferate when CD4(-)-, CD8(-)- splenocytes from MOG/IFA-immunized mice were regarded as antigen-presenting cells (APC). It was shown that these APC expressed lower levels of major histocompatibility complex class II (MHC-II), CD80, and CD86 than naïve cells. In addition, CD4(-)-, CD8(-)- splenocytes from MOG/IFA-immunized mice showed significantly higher levels of IL-10 mRNA expression. When the immunized-mice were induced to develop EAE, these cells secreted significantly higher levels of IL-10 and produced lower levels of IL-6, leading to decreased secretion of IL-17 and IFN-γ from MOG-specific CD4(+) T cells. The transfer of CD4(-)-, CD8(-)- splenocytes from MOG/IFA-immunized mice was able to ameliorate the subsequent induction of EAE in recipient mice. Thus, MOG/IFA immunization can modulate CD4(-)-, CD8(-)- splenocytes by reducing the expression of antigen-presenting molecules and altering the levels of secreted cytokines. Our study reveals an additional mechanism involved in the protective effects of MOG/IFA pre-immunization in an EAE model. Copyright © 2013 Elsevier B.V. All rights reserved.

LRD-22, a novel dual dithiocarbamatic acid ester, inhibits Aurora-A kinase and induces apoptosis and cell cycle arrest in HepG2 cells

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

Wang, Huiling; Li, Ridong; Li, Li

In this study we investigated the antitumor activity of the novel dual dithiocarbamatic acid ester LRD-22 in vitro and in vivo. Several cancer cell lines were employed to determine the effect of LRD-22 on cell growth, and the MTT assay showed there was a significant decrease in viable tumor cell numbers in the presence of LRD-22, especially in the HepG2 cell line. Colony formation assay also showed LRD-22 strongly inhibits HepG2 cell growth. Evaluation of the mechanism involved showed that inhibitory effects of LRD-22 on cell growth are due to induction of apoptosis and G2/M arrest. LRD-22 inhibited Aurora-A phosphorylation at Thr{submore » 288} and subsequently impaired p53 phosphorylation at Ser{sub 315} which was associated with the proteasome degradation pathway. Tumor suppressor protein p53 is stabilized by this mechanism and accumulates through inhibition of Aurora-A kinase activity via treatment with LRD-22. In vivo study of HepG2 xenograft in nude mice also shows LRD-22 suppresses tumor growth at a concentration of 5 mg/kg without animals suffering loss of body weight. In conclusion, our results demonstrate LRD-22 acts as an Aurora-A kinase inhibitor to induce apoptosis and inhibit proliferation in HepG2 cells, and should be considered as a promising targeting agent for HCC therapy. - Highlights: • LRD-22 significantly inhibits cancer cell growth, especially in the HepG2 cell line. • The inhibitory effect of LRD-22 is due to induction of apoptosis and cell cycle arrest. • LRD-22 inhibits Aurora-A phosphorylation which results in subsequent impairment of the p53 pathway. • LRD-22 suppresses tumor growth in xenograft mice without body weight loss.« less

Intestinal Epithelial Cells Modulate Antigen-Presenting Cell Responses to Bacterial DNA

PubMed Central

Campeau, J. L.; Salim, S. Y.; Albert, E. J.; Hotte, N.

2012-01-01

Intestinal epithelial cells and antigen-presenting cells orchestrate mucosal innate immunity. This study investigated the role of bacterial DNA in modulating epithelial and bone marrow-derived antigen-presenting cells (BM-APCs) and subsequent T-lymphocyte responses. Murine MODE-K epithelial cells and BM-APCs were treated with DNA from either Bifidobacterium breve or Salmonella enterica serovar Dublin directly and under coculture conditions with CD4+ T cells. Apical stimulation of MODE-K cells with S. Dublin DNA enhanced secretion of cytokines from underlying BM-APCs and induced interleukin-17 (IL-17) and gamma interferon (IFN-γ) secretion from CD4+ T cells. Bacterial DNA isolated from either strain induced maturation and increased cytokine secretion from BM-APCs. Conditioned medium from S. Dublin-treated MODE-K cells elicited an increase in cytokine secretion similar to that seen for S. Dublin DNA. Treatment of conditioned medium from MODE-K cells with RNase and protease prevented the S. Dublin-induced increased cytokine secretion. Oral feeding of mice with B. breve DNA resulted in enhanced levels of colonic IL-10 and transforming growth factor β (TGFβ) compared with what was seen for mice treated with S. Dublin DNA. In contrast, feeding mice with S. Dublin DNA increased levels of colonic IL-17 and IL-12p70. T cells from S. Dublin DNA-treated mice secreted high levels of IL-12 and IFN-γ compared to controls and B. breve DNA-treated mice. These results demonstrate that intestinal epithelial cells are able to modulate subsequent antigen-presenting and T-cell responses to bacterial DNA with pathogenic but not commensal bacterial DNA inducing effector CD4+ T lymphocytes. PMID:22615241

Intra-tumoral delivery of CXCL11 via a vaccinia virus, but not by modified T cells, enhances the efficacy of adoptive T cell therapy and vaccines.

PubMed

Moon, Edmund K; Wang, Liang-Chuan S; Bekdache, Kheng; Lynn, Rachel C; Lo, Albert; Thorne, Stephen H; Albelda, Steven M

2018-01-01

T cell trafficking into tumors depends on a "match" between chemokine receptors on effector cells (e.g., CXCR3 and CCR5) and tumor-secreted chemokines. There is often a chemokine/chemokine receptor "mismatch", with tumors producing minute amounts of chemokines, resulting in inefficient targeting of effectors to tumors. We aimed to alter tumors to produce higher levels of CXCL11, a CXCR3 ligand, to attract more effector cells following immunotherapy. Mice bearing established subcutaneous tumors were studied. In our first approach, we used modified chimeric antigen receptor (CAR)-transduced human T cells to deliver CXCL11 (CAR/CXCL11) into tumors. In our second approach, we intravenously (iv) administered a modified oncolytic vaccinia virus (VV) engineered to produce CXCL11 (VV.CXCL11). The effect of these treatments on T cell trafficking into the tumors and anti-tumor efficacy after subsequent CAR T cell injections or anti-tumor vaccines was determined. CAR/CXCL11 and VV.CXCL11 significantly increased CXCL11 protein levels within tumors. For CAR/CXCL11, injection of a subsequent dose of CAR T cells did not result in increased intra-tumoral trafficking, and appeared to decrease the function of the injected CAR T cells. In contrast, VV.CXCL11 increased the number of total and antigen-specific T cells within tumors after CAR T cell injection or vaccination and significantly enhanced anti-tumor efficacy. Both approaches were successful in increasing CXCL11 levels within the tumors; however, only the vaccinia approach was successful in recruiting T cells and augmenting anti-tumor efficacy. VV.CXCL11 should be considered as a potential approach to augment adoptive T cell transfer or vaccine immunotherapy.

[Future directions of molecular bone cell biology].

PubMed

Yoneda, T

2001-01-01

Introduction of genetic approaches using knockout and/or transgenic mice has produced many pieces of information that can't be obtained by conventional cell biological studies and profoundly advanced our understanding of bone biology and metabolism. Here, the author will first briefly summarize the current findings in the recent bone research and subsequently attempt to predict future directions to which bone research is going to proceed with a special emphasis of osteoclast and osteoblast biology.

Neurotrophin Signaling via Long-Distance Axonal Transport

NASA Astrophysics Data System (ADS)

Chowdary, Praveen D.; Che, Dung L.; Cui, Bianxiao

2012-05-01

Neurotrophins are a family of target-derived growth factors that support survival, development, and maintenance of innervating neurons. Owing to the unique architecture of neurons, neurotrophins that act locally on the axonal terminals must convey their signals across the entire axon for subsequent regulation of gene transcription in the cell nucleus. This long-distance retrograde signaling, a motor-driven process that can take hours or days, has been a subject of intense interest. In the last decade, live-cell imaging with high sensitivity has significantly increased our capability to track the transport of neurotrophins, their receptors, and subsequent signals in real time. This review summarizes recent research progress in understanding neurotrophin-receptor interactions at the axonal terminal and their transport dynamics along the axon. We emphasize high-resolution studies at the single-molecule level and also discuss recent technical advances in the field.

Cerebrovascular accidents in sickle cell disease. Risk factors and blood transfusion influence. French Study Group on Sickle Cell Disease.

PubMed

de Montalembert, M; Beauvais, P; Bachir, D; Galacteros, F; Girot, R

1993-03-01

This study presents a series of 34 sickle cell patients with one or more cerebrovascular accidents (CVA). Risk factors were studied in a subgroup of 19 patients whose clinical and biological characteristics were compared to those of a group of 444 sickle cell patients without CVA. The only risk factor discovered was a past history of purulent meningitis, which was significantly more frequent in sickle cell patients than in those without CVA (P < 0.0001). No biological or radiological factor affecting the risk of recurrence was found. The risk of recurrence, neurological defects or death after subsequent CVA justify long-term transfusion treatment in patients presenting with a second CVA. However our study shows that 10 patients who were not transfused after their first CVA had no recurrences, (median follow up = 7.9 years; 2-18 years), providing a basis for discussion on the indications of long-term transfusion therapy for sickle cell patients presenting with their first CVA.

In vivo imaging of emerging endocrine cells reveals a requirement for PI3K-regulated motility in pancreatic islet morphogenesis

PubMed Central

Freudenblum, Julia; Iglesias, José A.; Hermann, Martin; Walsen, Tanja; Wilfinger, Armin; Meyer, Dirk

2018-01-01

ABSTRACT The three-dimensional architecture of the pancreatic islet is integral to beta cell function, but the process of islet formation remains poorly understood due to the difficulties of imaging internal organs with cellular resolution. Within transparent zebrafish larvae, the developing pancreas is relatively superficial and thus amenable to live imaging approaches. We performed in vivo time-lapse and longitudinal imaging studies to follow islet development, visualizing both naturally occurring islet cells and cells arising with an accelerated timecourse following an induction approach. These studies revealed previously unappreciated fine dynamic protrusions projecting between neighboring and distant endocrine cells. Using pharmacological compound and toxin interference approaches, and single-cell analysis of morphology and cell dynamics, we determined that endocrine cell motility is regulated by phosphoinositide 3-kinase (PI3K) and G-protein-coupled receptor (GPCR) signaling. Linking cell dynamics to islet formation, perturbation of protrusion formation disrupted endocrine cell coalescence, and correlated with decreased islet cell differentiation. These studies identified novel cell behaviors contributing to islet morphogenesis, and suggest a model in which dynamic exploratory filopodia establish cell-cell contacts that subsequently promote cell clustering. PMID:29386244

The Stromal Vascular Fraction From Fat Tissue in the Treatment of Osteochondral Knee Defect: Case Report

PubMed Central

Salikhov, Ramil Z.; Masgutov, Ruslan F.; Chekunov, Mikhail A.; Tazetdinova, Leysan G.; Masgutova, Galina; Teplov, Oleg V.; Galimov, Damir; Plakseichuk, Yuri; Yagudin, Ramil; Pankov, Igor O.; Rizvanov, Albert

2018-01-01

In this study we applied autologous fat tissue stromal vascular fraction (SVF) cells in combination with microfracturing technique in a 36-year-old man with an osteochondral lesion of the medial femoral condyle 8 months after the injury. Cell material was generated by fat tissue liposuction from the anterior abdominal wall with subsequent extraction of the SVF and injected through a mini-arthrotomy portal with subsequent fibrin sealant fixation. The follow-up period was 2 years. Clinical score improved from 23 to 96 according to IKDC and from 10 to 90 according to EQ-VAS at 24 months follow-up. Magnetic resonance imaging (MRI) before the surgery revealed an osteochondral lesion with development of significant trabecular edema that remained unchanged for 6 months despite conservative treatment. MRI 1 and 2 years after the surgery showed the recovery of the damaged cartilage thickness with somewhat uneven structure and a decrease in the trabecular edema of the femoral condyle. The use of SVF cells with fibrin sealant fixation might be a promising approach in the treatment of osteochondral joint lesions. Further studies are required. PMID:29900170

Live imaging of wound angiogenesis reveals macrophage orchestrated vessel sprouting and regression.

PubMed

Gurevich, David B; Severn, Charlotte E; Twomey, Catherine; Greenhough, Alexander; Cash, Jenna; Toye, Ashley M; Mellor, Harry; Martin, Paul

2018-06-04

Wound angiogenesis is an integral part of tissue repair and is impaired in many pathologies of healing. Here, we investigate the cellular interactions between innate immune cells and endothelial cells at wounds that drive neoangiogenic sprouting in real time and in vivo Our studies in mouse and zebrafish wounds indicate that macrophages are drawn to wound blood vessels soon after injury and are intimately associated throughout the repair process and that macrophage ablation results in impaired neoangiogenesis. Macrophages also positively influence wound angiogenesis by driving resolution of anti-angiogenic wound neutrophils. Experimental manipulation of the wound environment to specifically alter macrophage activation state dramatically influences subsequent blood vessel sprouting, with premature dampening of tumour necrosis factor-α expression leading to impaired neoangiogenesis. Complementary human tissue culture studies indicate that inflammatory macrophages associate with endothelial cells and are sufficient to drive vessel sprouting via vascular endothelial growth factor signalling. Subsequently, macrophages also play a role in blood vessel regression during the resolution phase of wound repair, and their absence, or shifted activation state, impairs appropriate vessel clearance. © 2018 The Authors. Published under the terms of the CC BY 4.0 license.

Intrinsic and extrinsic mechanisms regulating satellite cell function

PubMed Central

Dumont, Nicolas A.; Wang, Yu Xin; Rudnicki, Michael A.

2015-01-01

Muscle stem cells, termed satellite cells, are crucial for skeletal muscle growth and regeneration. In healthy adult muscle, satellite cells are quiescent but poised for activation. During muscle regeneration, activated satellite cells transiently re-enter the cell cycle to proliferate and subsequently exit the cell cycle to differentiate or self-renew. Recent studies have demonstrated that satellite cells are heterogeneous and that subpopulations of satellite stem cells are able to perform asymmetric divisions to generate myogenic progenitors or symmetric divisions to expand the satellite cell pool. Thus, a complex balance between extrinsic cues and intrinsic regulatory mechanisms is needed to tightly control satellite cell cycle progression and cell fate determination. Defects in satellite cell regulation or in their niche, as observed in degenerative conditions such as aging, can impair muscle regeneration. Here, we review recent discoveries of the intrinsic and extrinsic factors that regulate satellite cell behaviour in regenerating and degenerating muscles. PMID:25922523

5-(Furan-2-yl)-4-(3,4,5-trimethoxyphenyl)-3H-1,2-dithiol-3-one oxime (6f), a new synthetic compound, causes human fibrosarcoma HT-1080 cell apoptosis by disrupting tubulin polymerisation and inducing G2/M arrest.

PubMed

Zuo, Daiying; Pang, Lili; Shen, Jiwei; Guan, Qi; Bai, Zhaoshi; Zhang, Huijuan; Li, Yao; Lu, Guodong; Zhang, Weige; Wu, Yingliang

2017-06-01

In the current study, we synthesized a series of new compounds targeting tubulin and tested their anti-proliferative activities. Among these new synthetic com-pounds, 5-(furan-2-yl)-4-(3,4,5-trimethoxyphenyl)-3H-1,2-dithiol-3-one oxime (6f) exhibited significant anti-proliferative activity against different human cancer cell lines including human gastric adenocarcinoma SGC-7901, human non-small cell lung cancer A549, and human fibrosarcoma HT-1080. As a result, 6f was selected to further test the sensitivity to different cancer cell lines including human cervical cancer cell line HeLa, human breast cancer cell line MCF-7, non-small cell lung cancer cell line A549, human liver carcinoma cell line HepG-2, human oral squamous cell carcinoma cell lines KB, SGC-7901 and HT-1080. Among these cell lines, HT-1080 and HeLa are the most sensitive. Therefore, HT-1080 was selected to further explore the properties of anti-proliferative activity and the underlying mechanisms. Our data proved that 6f exhibited strong anti-proliferative effects against HT-1080 cells in a time- and dose-dependent manner. We showed that the growth inhibitory effect of 6f in HT-1080 cells was related with microtubule depolymerisation. Molecular docking studies revealed that 6f interacted and bound efficiently with the colchicine-binding site of tubulin. In addition, 6f treatment induced G2/M cell cycle arrest dose-dependently and subsequently induced cell apoptosis. Western blot study indicated that upregulation of cyclin B1 and p-cdc2 was related with G2/M arrest. 6f-induced cell apoptosis was associated with both mitochondrial and death receptor pathway. In conclusion, our data showed that 6f, among the newly synthetic compounds, exhibited highest anti-proliferative activity by disrupting the microtubule polymerisation, causing G2/M arrest and subsequently inducing cell apoptosis in HT-1080 cells. Hence, 6f is a promising microtubule depolymerising agent for the treatment of various cancers especially human fibrosarcoma.

Preparation of HIV monoclonal antibody-conjugated pulchellin in order to study its intracellular trafficking pathway in HIV-infected cells by confocal microscopy

NASA Astrophysics Data System (ADS)

Sadraeian, M.; Tsutae, F. M.; Moreira, H. H. T.; Araujo, A. P. U.; Guimarães, F. E. G.; Pincus, S. H.

2015-06-01

Pulchellin is a type 2 of ribosome-inactivating proteins isolated from some seeds significantly growing in Brazil. It is a potent agent to inhibit the protein synthesis in cancer cells and also HIV-infected cells. Pulchellin can be conjugated to HIV monoclonal antibodies to specifically target the HIV-infected cells. To analyze the protein synthesis inhibition by Pulchellin, the intracellular localization of the immunoconjugate should be compared to Pulchellin. In this case, the intracellular trafficking of this protein in cells can be determined by confocal microscopy. In our study, we utilized Pulchellin to construct HIV monoclonal antibody-conjugated Pulchellin A chain in order to target HIV-infected lymphocyte cells. Afterward the conjugation was labeled with the superior Alexa Fluor 488 dye. As a subsequent step, we are interested in studying the intracellular trafficking pathway of this novel conjugation in HIV-infected cells by confocal microscopy. Moreover, possible quantitative methods for fluorescent labeling of the immunoconjugate during confocal microscopy will be investigated.

Inhibitory effect of indigo naturalis on tumor necrosis factor-α-induced vascular cell adhesion molecule-1 expression in human umbilical vein endothelial cells.

PubMed

Chang, Hsin-Ning; Pang, Jong-Hwei Su; Yang, Sien-Hung; Hung, Chi-Feng; Chiang, Chi-Hsin; Lin, Tung-Yi; Lin, Yin-Ku

2010-09-14

The use of indigo naturalis to treat psoriasis has proved effective in our previous clinical studies. The present study was designed to examine the anti-inflammatory effect of indigo naturalis in primary cultured human umbilical vein endothelial cells (HUVECs). Pretreatment of cells with indigo naturalis extract attenuated TNF-α-induced increase in Jurkat T cell adhesion to HUVECs as well as decreased the protein and messenger (m)RNA expression levels of vascular cell adhesion molecule-1 (VCAM-1) on HUVECs. Indigo naturalis extract also inhibited the protein expression of activator protein-1 (AP-1)/c-Jun, a critical transcription factor for the activation of VCAM-1 gene expression. Since the reduction of lymphocyte adhesion to vascular cells by indigo naturalis extract could subsequently reduce the inflammatory reactions caused by lymphocyte infiltration in the epidermal layer and help to improve psoriasis, this study provides a potential mechanism for the anti-inflammatory therapeutic effect of indigo naturalis extract in psoriasis.

Gene Profiling Characteristics of Radioadaptive Response in AG01522 Normal Human Fibroblasts

PubMed Central

Hou, Jue; Wang, Fan; Kong, Peizhong; Yu, Peter K. N.; Wang, Hongzhi; Han, Wei

2015-01-01

Radioadaptive response (RAR) in mammalian cells refers to the phenomenon where a low-dose ionizing irradiation alters the gene expression profiles, and protects the cells from the detrimental effects of a subsequent high dose exposure. Despite the completion of numerous experimental studies on RAR, the underlying mechanism has remained unclear. In this study, we aimed to have a comprehensive investigation on the RAR induced in the AG01522 human fibroblasts first exposed to 5 cGy (priming dose) and then followed by 2 Gy (challenge dose) of X-ray through comparisons to those cells that had only received a single 2 Gy dose. We studied how the priming dose affected the expression of gene transcripts, and to identify transcripts or pathways that were associated with the reduced chromosomal damages (in terms of the number of micronuclei) after application of the challenging dose. Through the mRNA and microRNA microarray analyses, the transcriptome alteration in AG01522 cells was examined, and the significantly altered genes were identified for different irradiation procedures using bioinformatics approaches. We observed that a low-dose X-ray exposure produced an alert, triggering and altering cellular responses to defend against subsequent high dose-induced damages, and accelerating the cell repair process. Moreover, the p53 signaling pathway was found to play critial roles in regulating DNA damage responses at the early stage after application of the challenging dose, particularly in the RAR group. Furthermore, microRNA analyses also revealed that cell communication and intercellular signaling transduction played important roles after low-dose irradiation. We conclude that RAR benefits from the alarm mechanisms triggered by a low-dose priming radation dose. PMID:25886619

Beneficial effect of resveratrol on bovine oocyte maturation and subsequent embryonic development after in vitro fertilization.

PubMed

Wang, Feng; Tian, XiuZhi; Zhang, Lu; He, ChangJiu; Ji, PengYun; Li, Yu; Tan, DunXian; Liu, GuoShi

2014-02-01

To analyze the potential beneficial effects and mechanisms of action of resveratrol on the maturation of bovine oocytes that were incubated in different concentrations of resveratrol (0.1, 1.0, or 10.0 μM) as germinal vesicle-stage oocytes. In vitro prospective study. University research laboratory. Animal models for human studies. In vitro culture in the presence of various concentrations of the antioxidant resveratrol. Parameters of hormone levels, oocyte nuclear maturation, cumulus expansion, levels of intracellular glutathione and reactive oxygen species, embryonic cleavage, blastocyst formation, gene expression associated with mature bovine oocytes and cumulus cells, and level of sirtuin 1 gene expression. Resveratrol statistically significantly increased progesterone secretion and decreased estradiol-17β secretion by cumulus cells. The elevated levels of progesterone activated the Mos/MEK/p42 mitogen-activated protein kinase (MAPK) cascade in the oocytes. At a concentration of 1.0 μM, resveratrol statistically significantly improved cumulus expansion, polar body formation, the (hatched) blastocyst rate, and the mean number of cells/blastocysts. Meanwhile, resveratrol statistically significantly reduced the level of reactive oxygen species (ROS) and increased the level of glutathione (GSH). For the first time, the expression of the sirtuin-1 gene was identified in granulosa cells, cumulus cells, oocytes, and blastocysts. Further studies revealed that resveratrol promoted sirtuin-1 gene expression. Resveratrol promoted bovine oocyte maturation and subsequent post-in vitro fertilization embryonic development by inducing progesterone secretion and an antioxidant effect, probably in a manner dependent on sirtuin-1. Copyright © 2014 American Society for Reproductive Medicine. All rights reserved.

Antioxidants and phenolic secretion in sugarcane genotypes shoot culture

USDA-ARS?s Scientific Manuscript database

The secretion of phenolic compounds is a major limitation for sugarcane in vitro culture, causing a loss of regenerative capacity and subsequent cell death. In this study, micropropagation and phenolic secretion of four Saccharum genotypes in the presence of different antioxidants were evaluated. As...

Staphylococcus aureus infection of mice expands a population of memory γδ T cells that are protective against subsequent infection

PubMed Central

Murphy, Alison G.; O’Keeffe, Kate M.; Lalor, Stephen J.; Maher, Belinda M.; Mills, Kingston H. G.; McLoughlin, Rachel M.

2014-01-01

The development of vaccines against S. aureus has consistently failed in clinical trials, likely due to inefficient induction of cellular immunity. T cell-derived IL-17 is one of the few known correlates of anti-staphyloccoal immunity, conferring protection against S. aureus infections through its ability to promote phagocytic cell effector functions. A comprehensive understanding of the discrete T cell subsets critical for site-specific IL-17-mediated bacterial clearance will therefore be necessary to inform the development of vaccines that efficiently target cellular immunity. In this study, we have identified a population of CD44+CD27− memory γδ T cells, expanded upon infection of C57BL/6 mice with S. aureus, which produce high levels of IL-17 and mediate enhanced bacterial clearance upon re-infection with the bacterium. These cells are comprised largely of the Vγ4+ subset and accumulate at the site of infection subsequent to an initial Vγ1.1+ and Vγ2+ T cell response. Moreover, these Vγ4+ T cells are retained in the peritoneum and draining mediastinal lymph nodes for a prolonged period following bacterial clearance. In contrast to its critical requirement for γδ T cell activation during the primary infection, IL-1 signalling was dispensable for activation and expansion of memory γδ T cells upon re-exposure to S. aureus. Our findings demonstrate that a γδ T cell memory response can be induced upon exposure to S. aureus, in a fashion analogous to that associated with classical αβ T cells, and suggest that induction of IL-17-expressing γδ T cells may be an important property of a protective vaccine against S. aureus. PMID:24623128

p38 Mitogen-Activated Protein Kinase/Signal Transducer and Activator of Transcription-3 Pathway Signaling Regulates Expression of Inhibitory Molecules in T Cells Activated by HIV-1–Exposed Dendritic Cells

PubMed Central

Che, Karlhans Fru; Shankar, Esaki Muthu; Muthu, Sundaram; Zandi, Sasan; Sigvardsson, Mikael; Hinkula, Jorma; Messmer, Davorka; Larsson, Marie

2012-01-01

Human immunodeficiency virus type 1 (HIV-1) infection enhances the expression of inhibitory molecules on T cells, leading to T-cell impairment. The signaling pathways underlying the regulation of inhibitory molecules and subsequent onset of T-cell impairment remain elusive. We showed that both autologous and allogeneic T cells exposed to HIV-pulsed dendritic cells (DCs) upregulated cytotoxic T-lymphocyte antigen (CTLA-4), tumor-necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), lymphocyte-activation gene-3 (LAG3), T-cell immunoglobulin mucin-3 (TIM-3), CD160 and certain suppression-associated transcription factors, such as B-lymphocyte induced maturation protein-1 (BLIMP-1), deltex homolog 1 protein (DTX1) and forkhead box P3 (FOXP3), leading to T-cell suppression. This induction was regulated by p38 mitogen-activated protein kinase/signal transducer and activator of transcription-3 (P38MAPK/STAT3) pathways, because their blockade significantly abrogated expression of all the inhibitory molecules studied and a subsequent recovery in T-cell proliferation. Neither interleukin-6 (IL-6) nor IL-10 nor growth factors known to activate STAT3 signaling events were responsible for STAT3 activation. Involvement of the P38MAPK/STAT3 pathways was evident because these proteins had a higher level of phosphorylation in the HIV-1–primed cells. Furthermore, blockade of viral CD4 binding and fusion significantly reduced the negative effects DCs imposed on primed T cells. In conclusion, HIV-1 interaction with DCs modulated their functionality, causing them to trigger the activation of the P38MAPK/STAT3 pathway in T cells, which was responsible for the upregulation of inhibitory molecules. PMID:22777388

The evolving roles of memory immune cells in transplantation

PubMed Central

Chen, Wenhao; Ghobrial, Rafik M.; Li, Xian C.

2015-01-01

Memory cells are the products of immune responses but also exert significant impact on subsequent immunity and immune tolerance, thus placing them in a unique position in transplant research. Memory cells are heterogeneous, including not only memory T cells but also memory B cells and innate memory cells. Memory cells are a critical component of protective immunity against invading pathogens, especially in immunosuppressed patients, but they also mediate graft loss and tolerance resistance. Recent studies suggest that some memory cells unexpectedly act as regulatory cells, promoting rather than hindering transplant survival. This functional diversity makes therapeutic targeting of memory cells a challenging task in transplantation. In this article we highlight recent advances in our understanding of memory cells, focusing on diversity of memory cells and mechanisms involved in their induction and functions. We also provide a broad overview on the challenges and opportunities in targeting memory cells in the induction of transplant tolerance. PMID:26102615

Analysis of early mesothelial cell responses to Staphylococcus epidermidis isolated from patients with peritoneal dialysis-associated peritonitis.

PubMed

McGuire, Amanda L; Mulroney, Kieran T; Carson, Christine F; Ram, Ramesh; Morahan, Grant; Chakera, Aron

2017-01-01

The major complication of peritoneal dialysis (PD) is the development of peritonitis, an infection within the abdominal cavity, primarily caused by bacteria. PD peritonitis is associated with significant morbidity, mortality and health care costs. Staphylococcus epidermidis is the most frequently isolated cause of PD-associated peritonitis. Mesothelial cells are integral to the host response to peritonitis, and subsequent clinical outcomes, yet the effects of infection on mesothelial cells are not well characterised. We systematically investigated the early mesothelial cell response to clinical and reference isolates of S. epidermidis using primary mesothelial cells and the mesothelial cell line Met-5A. Using an unbiased whole genome microarray, followed by a targeted panel of genes known to be involved in the human antibacterial response, we identified 38 differentially regulated genes (adj. p-value < 0.05) representing 35 canonical pathways after 1 hour exposure to S. epidermidis. The top 3 canonical pathways were TNFR2 signaling, IL-17A signaling, and TNFR1 signaling (adj. p-values of 0.0012, 0.0012 and 0.0019, respectively). Subsequent qPCR validation confirmed significant differences in gene expression in a number of genes not previously described in mesothelial cell responses to infection, with heterogeneity observed between clinical isolates of S. epidermidis, and between Met-5A and primary mesothelial cells. Heterogeneity between different S. epidermidis isolates suggests that specific virulence factors may play critical roles in influencing outcomes from peritonitis. This study provides new insights into early mesothelial cell responses to infection with S. epidermidis, and confirms the importance of validating findings in primary mesothelial cells.

Stem/progenitor cells derived from the cochlear sensory epithelium give rise to spheres with distinct morphologies and features.

PubMed

Diensthuber, Marc; Oshima, Kazuo; Heller, Stefan

2009-06-01

Nonmammalian vertebrates regenerate lost sensory hair cells by means of asymmetric division of supporting cells. Inner ear or lateral line supporting cells in birds, amphibians, and fish consequently serve as bona fide stem cells resulting in high regenerative capacity of hair cell-bearing organs. Hair cell regeneration does not happen in the mammalian cochlea, but cells with proliferative capacity can be isolated from the neonatal cochlea. These cells have the ability to form clonal floating colonies, so-called spheres, when cultured in nonadherent conditions. We noticed that the sphere population derived from mouse cochlear sensory epithelium cells was heterogeneous, consisting of morphologically distinct sphere types, hereby classified as solid, transitional, and hollow. Cochlear sensory epithelium-derived stem/progenitor cells initially give rise to small solid spheres, which subsequently transition into hollow spheres, a change that is accompanied by epithelial differentiation of the majority of sphere cells. Only solid spheres, and to a lesser extent, transitional spheres, appeared to harbor self-renewing stem cells, whereas hollow spheres could not be consistently propagated. Solid spheres contained significantly more rapidly cycling Pax-2-expressing presumptive otic progenitor cells than hollow spheres. Islet-1, which becomes upregulated in nascent sensory patches, was also more abundant in solid than in hollow spheres. Likewise, hair cell-like cells, characterized by the expression of multiple hair cell markers, differentiated in significantly higher numbers in cell populations derived from solid spheres. We conclude that cochlear sensory epithelium cell populations initially give rise to small solid spheres that have self-renewing capacity before they subsequently convert into hollow spheres, a process that is accompanied by loss of stemness and reduced ability to spontaneously give rise to hair cell-like cells. Solid spheres might, therefore, represent the most suitable sphere type for cell-based assays or animal model transplantation studies aimed at development of cell replacement therapies.

The effect of ex vivo CDDO-Me activation on nuclear factor erythroid 2-related factor 2 pathway in white blood cells from patients with septic shock.

PubMed

Noel, Sanjeev; Zheng, Laura; Navas-Acien, Ana; Fuchs, Ralph J

2014-11-01

Nuclear factor erythroid 2-related factor 2 (NRF2) has been shown to protect against experimental sepsis in mice and lipopolysaccharide (LPS)-induced inflammation in ex vivo white blood cells from healthy subjects by upregulating cellular antioxidant genes. The objective of this study was to test the hypothesis that ex vivo methyl 2-cyano-3,12-dioxoolean-1,9-dien-28-oate (CDDO-Me) activates NRF2-regulated antioxidant genes in white blood cells from patients with septic shock and protects against LPS-induced inflammation and reactive oxidative species production. Peripheral blood was collected from 18 patients with septic shock who were being treated in medical and surgical intensive care units. Real-time polymerase chain reaction was used to quantify the expression of NRF2 target genes (NQO1, HO-1, GCLM, and FTL) and IL-6 in peripheral blood mononuclear cells (PBMCs), monocytes, and neutrophils after CDDO-Me treatment alone or after subsequent LPS exposure. Superoxide anion (O2) was measured to assess the effect of CDDO-Me pretreatment on subsequent LPS exposure. Treatment with CDDO-Me increased the gene expression of NQO1 (P = 0.04) and decreased the expression of HO-1 (P = 0.03) in PBMCs from patients with septic shock. Purified monocytes exhibited significant increases in the expression of NQO1 (P = 0.01) and GCLM (P = 0.003) after CDDO-Me treatment. Levels of other NRF2 target genes (HO-1 and FTL) remained similar to those of vehicle-treated cells. Peripheral blood mononuclear cells showed a trend toward increased IL-6 gene expression after CDDO-Me treatment, whereas purified monocytes showed a trend toward decreased IL-6. There was no discernible trend in the IL-6 expression subsequent to LPS treatment in either vehicle-treated or CDDO-Me-treated PBMCs and monocytes. Treatment with CDDO-Me significantly increased O2 production in PBMCs (P = 0.04). Although CDDO-Me pretreatment significantly attenuated O2 production to subsequent LPS exposure (P = 0.03), the change was comparable to that observed in vehicle-treated PBMCs. Pretreatment with CDDO-Me followed by LPS exposure had no significant effect on O2 levels in purified monocytes. These data suggest that the NRF2 pathway is differentially responsive to CDDO-Me activation in peripheral blood cells from patients with septic shock and results in increased O2 production. The data may also suggest a suppressed NRF2 pathway in white blood cells from critically ill patients.

Effects of topographical and mechanical property alterations induced by oxygen plasma modification on stem cell behavior.

PubMed

Yang, Yong; Kulangara, Karina; Lam, Ruby T S; Dharmawan, Rena; Leong, Kam W

2012-10-23

Polymeric substrates intended for cell culture and tissue engineering are often surface-modified to facilitate cell attachment of most anchorage-dependent cell types. The modification alters the surface chemistry and possibly topography. However, scant attention has been paid to other surface property alterations. In studying oxygen plasma treatment of polydimethylsiloxane (PDMS), we show that oxygen plasma treatment alters the surface chemistry and, consequently, the topography and elasticity of PDMS at the nanoscale level. The elasticity factor has the predominant effect, compared with the chemical and topographical factors, on cell adhesions of human mesenchymal stem cells (hMSCs). The enhanced focal adhesions favor cell spreading and osteogenesis of hMSCs. Given the prevalent use of PDMS in biomedical device construction and cell culture experiments, this study highlights the importance of understanding how oxygen plasma treatment would impact subsequent cell-substrate interactions. It helps explain inconsistency in the literature and guides preparation of PDMS-based biomedical devices in the future.

Rottlerin upregulates DDX3 expression in hepatocellular carcinoma.

PubMed

Wang, Zhong; Shen, Gen-Hai; Xie, Jia-Ming; Li, Bin; Gao, Quan-Gen

2018-01-01

Rottlerin has been reported to exert its anti-tumor activity in various types of human cancers. However, the underlying molecular mechanism has not been fully elucidated. In the current study, we explored whether rottlerin exhibits its tumor suppressive function in hepatocellular carcinoma cells. Our MTT assay results showed that rottlerin inhibited cell growth in hepatocellular carcinoma cells. Moreover, we found that rottlerin induced cell apoptosis and caused cell cycle arrest at G1 phase. Furthermore, our wound healing assay result demonstrated that rottlerin retarded cell migration in hepatocellular carcinoma cells. Additionally, rottlerin suppressed cell migration and invasion. Notably, we found that rottlerin upregulated DDX3 expression and subsequently downregulated Cyclin D1 expression and increased p21 level. Importantly, down-regulation of DDX3 abrogated the rottlerin-mediated tumor suppressive function, whereas overexpression of DDX3 promoted the anti-tumor activity of rottlerin. Our study suggests that rottlerin exhibits its anti-cancer activity partly due to upregulation of DDX3 in hepatocellular carcinoma cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Characterization of gonadal soma-derived factor expression during sex change in the protogynous wrasse, Halichoeres trimaculatus.

PubMed

Horiguchi, Ryo; Nozu, Ryo; Hirai, Toshiaki; Kobayashi, Yasuhisa; Nagahama, Yoshitaka; Nakamura, Masaru

2013-04-01

Sex change in fishes provides a good experimental model for understanding the mechanisms and plasticity of sex determination and differentiation. The three-spot wrasse, Halichoeres trimaculatus is a protogynous hermaphrodite. During sex change from female to male, the ovary is replaced by the testis through the degeneration of oocytes and subsequent spermatogenesis. In the present study, we cloned a cDNA-encoding gonadal soma-derived factor (GSDF) from protogynous wrasse and examined its expression pattern in the sexually mature gonads and the sex-changing gonad induced experimentally by aromatase inhibition. Expression of gsdf was predominantly observed in the testis, and it was mainly localized to the supporting cells surrounding the spermatogonia. In the ovary, only slight expression of gsdf was observed in morphologically undifferentiated supporting cells in contact with oogonia. During sex change, strong expression of gsdf appeared first in the supporting cells surrounding the gonial germ cells before the onset of spermatogenesis. Thereafter, the expression of gsdf continually increased in the supporting cells surrounding the proliferating spermatogonia throughout the sex change. These results suggest that gsdf is involved in the proliferation of spermatogonia and subsequent spermatogenesis in both the testis and the gonad in the early stages of sex change. Copyright © 2013 Wiley Periodicals, Inc.

Functional Reintegration of Sensory Neurons and Transitional Dendritic Reduction of Mitral/Tufted Cells during Injury-Induced Recovery of the Larval Xenopus Olfactory Circuit.

PubMed

Hawkins, Sara J; Weiss, Lukas; Offner, Thomas; Dittrich, Katarina; Hassenklöver, Thomas; Manzini, Ivan

2017-01-01

Understanding the mechanisms involved in maintaining lifelong neurogenesis has a clear biological and clinical interest. In the present study, we performed olfactory nerve transection on larval Xenopus to induce severe damage to the olfactory circuitry. We surveyed the timing of the degeneration, subsequent rewiring and functional regeneration of the olfactory system following injury. A range of structural labeling techniques and functional calcium imaging were performed on both tissue slices and whole brain preparations. Cell death of olfactory receptor neurons and proliferation of stem cells in the olfactory epithelium were immediately increased following lesion. New olfactory receptor neurons repopulated the olfactory epithelium and once again showed functional responses to natural odorants within 1 week after transection. Reinnervation of the olfactory bulb (OB) by newly formed olfactory receptor neuron axons also began at this time. Additionally, we observed a temporary increase in cell death in the OB and a subsequent loss in OB volume. Mitral/tufted cells, the second order neurons of the olfactory system, largely survived, but transiently lost dendritic tuft complexity. The first odorant-induced responses in the OB were observed 3 weeks after nerve transection and the olfactory network showed signs of major recovery, both structurally and functionally, after 7 weeks.

Functional Reintegration of Sensory Neurons and Transitional Dendritic Reduction of Mitral/Tufted Cells during Injury-Induced Recovery of the Larval Xenopus Olfactory Circuit

PubMed Central

Hawkins, Sara J.; Weiss, Lukas; Offner, Thomas; Dittrich, Katarina; Hassenklöver, Thomas; Manzini, Ivan

2017-01-01

Understanding the mechanisms involved in maintaining lifelong neurogenesis has a clear biological and clinical interest. In the present study, we performed olfactory nerve transection on larval Xenopus to induce severe damage to the olfactory circuitry. We surveyed the timing of the degeneration, subsequent rewiring and functional regeneration of the olfactory system following injury. A range of structural labeling techniques and functional calcium imaging were performed on both tissue slices and whole brain preparations. Cell death of olfactory receptor neurons and proliferation of stem cells in the olfactory epithelium were immediately increased following lesion. New olfactory receptor neurons repopulated the olfactory epithelium and once again showed functional responses to natural odorants within 1 week after transection. Reinnervation of the olfactory bulb (OB) by newly formed olfactory receptor neuron axons also began at this time. Additionally, we observed a temporary increase in cell death in the OB and a subsequent loss in OB volume. Mitral/tufted cells, the second order neurons of the olfactory system, largely survived, but transiently lost dendritic tuft complexity. The first odorant-induced responses in the OB were observed 3 weeks after nerve transection and the olfactory network showed signs of major recovery, both structurally and functionally, after 7 weeks. PMID:29234276

Anthocyanin-rich Aronox extract from Aronia melanocarpa E protects against 7beta-hydroxycholesterol-induced apoptosis of endothelial cells.

PubMed

Zapolska-Downar, Danuta; Nowicka, Grazyna; Sygitowicz, Grazyna; Jarosz, Mirosław

2008-01-01

It has been previously reported that dietary polyphenolic compounds have a positive effect in cardiovascular diseases, although the underlying mechanisms remain unknown. In this study, the effects of Aronox, an anthocyanin-rich extract from Aronia melanocarpa E, on human umbilical vein endothelial cell (HUVEC) apoptosis was investigated. Apoptosis was measured in HUVEC pretreated with Aronox and than treated with 7beta-hydroxycholesterol (20 microg/ml). For the evaluation of apoptosis we used the cell binding of annexin V, the propidium iodide uptake method and the TUNEL assay. We also measured the generation of reactive oxygen species (ROS) in the cells, using fluorescent probe 2',7'-dichlorofluorescein acetate. Moreover, alteration of the mitochondrial membrane potential with subsequent cytochrome c release, activation of caspase-3, and the level of anti-apoptotic Bcl-2 were investigated. Aronox significantly decreased 7beta-hydroxycholesterol-induced apoptosis and ROS generation, and ameliorated the collapse of the mitochondrial transmembrane potential with subsequent inhibition of cytochrome c release. Furthermore, down-regulation of Bcl-2 and up-regulation of caspase-3 activation were reversed by Aronox. The protective action of the extract against apoptosis in endothelial cells may contribute to the potential benefits drawn from consumption of plant polyphenols. Copyright 2009 S. Karger AG, Basel.

Nuclear translocation of Acinetobacter baumannii transposase induces DNA methylation of CpG regions in the promoters of E-cadherin gene.

PubMed

Moon, Dong Chan; Choi, Chul Hee; Lee, Su Man; Lee, Jung Hwa; Kim, Seung Il; Kim, Dong Sun; Lee, Je Chul

2012-01-01

Nuclear targeting of bacterial proteins has emerged as a pathogenic mechanism whereby bacterial proteins induce host cell pathology. In this study, we examined nuclear targeting of Acinetobacter baumannii transposase (Tnp) and subsequent epigenetic changes in host cells. Tnp of A. baumannii ATCC 17978 possesses nuclear localization signals (NLSs), (225)RKRKRK(230). Transient expression of A. baumannii Tnp fused with green fluorescent protein (GFP) resulted in the nuclear localization of these proteins in COS-7 cells, whereas the truncated Tnp without NLSs fused with GFP were exclusively localized in the cytoplasm. A. baumannii Tnp was found in outer membrane vesicles, which delivered this protein to the nucleus of host cells. Nuclear expression of A. baumannii Tnp fused with GFP in A549 cells induced DNA methylation of CpG regions in the promoters of E-cadherin (CDH1) gene, whereas the cytoplasmic localization of the truncated Tnp without NLSs fused with GFP did not induce DNA methylation. DNA methylation in the promoters of E-cadherin gene induced by nuclear targeting of A. baumannii Tnp resulted in down-regulation of gene expression. In conclusion, our data show that nuclear traffic of A. baumannii Tnp induces DNA methylation of CpG regions in the promoters of E-cadherin gene, which subsequently down-regulates gene expression. This study provides a new insight into the epigenetic control of host genes by bacterial proteins.

Infectivity of Plasmodium falciparum in Malaria-Naive Individuals Is Related to Knob Expression and Cytoadherence of the Parasite

PubMed Central

Stanisic, Danielle I.; Gerrard, John; Fink, James; Griffin, Paul M.; Liu, Xue Q.; Sundac, Lana; Sekuloski, Silvana; Rodriguez, Ingrid B.; Pingnet, Jolien; Yang, Yuedong; Zhou, Yaoqi; Trenholme, Katharine R.; Wang, Claire Y. T.; Hackett, Hazel; Chan, Jo-Anne A.; Langer, Christine; Hanssen, Eric; Hoffman, Stephen L.; Beeson, James G.; McCarthy, James S.

2016-01-01

Plasmodium falciparum is the most virulent human malaria parasite because of its ability to cytoadhere in the microvasculature. Nonhuman primate studies demonstrated relationships among knob expression, cytoadherence, and infectivity. This has not been examined in humans. Cultured clinical-grade P. falciparum parasites (NF54, 7G8, and 3D7B) and ex vivo-derived cell banks were characterized. Knob and knob-associated histidine-rich protein expression, CD36 adhesion, and antibody recognition of parasitized erythrocytes (PEs) were evaluated. Parasites from the cell banks were administered to malaria-naive human volunteers to explore infectivity. For the NF54 and 3D7B cell banks, blood was collected from the study participants for in vitro characterization. All parasites were infective in vivo. However, infectivity of NF54 was dramatically reduced. In vitro characterization revealed that unlike other cell bank parasites, NF54 PEs lacked knobs and did not cytoadhere. Recognition of NF54 PEs by immune sera was observed, suggesting P. falciparum erythrocyte membrane protein 1 expression. Subsequent recovery of knob expression and CD36-mediated adhesion were observed in PEs derived from participants infected with NF54. Knobless cell bank parasites have a dramatic reduction in infectivity and the ability to adhere to CD36. Subsequent infection of malaria-naive volunteers restored knob expression and CD36-mediated cytoadherence, thereby showing that the human environment can modulate virulence. PMID:27382019

Pathogenesis of Crimean-Congo hemorrhagic fever.

PubMed

Akıncı, Esragül; Bodur, Hürrem; Leblebicioglu, Hakan

2013-07-01

Although Crimean-Congo hemorrhagic fever (CCHF) is a widespread tick-borne disease, little is known about its pathogenesis. The interaction of the virus with host cells is most likely responsible for the pathogenesis of CCHF. The main contributors are endothelial cells (ECs) and immune cells. There are 2 theories underlying the CCHF pathogenesis: One is that the virus interacts with the ECs directly and the other that it interacts indirectly via immune cells with subsequent release of soluble mediators. ECs are activated upon infection by the upregulation of soluble molecules and proinflammatory cytokines. Probably, in severe cases, deregulation and excessive release of the cytokines accompanied by endothelial activation have toxic effects, leading to increased vascular permeability, vasodilatation, and subsequently hypotension, multiple organ failure, shock, and death. Studies indicate that CCHF virus (CCHFV) also can impair the innate immune system and cause a delay in adaptive immune response, which is critical for the clearance of CCHFV. The virus has many different ways to block the immune response, leading to uncontrolled viral replication followed by systemic spread of the virus throughout the body. Partial activation of dendritic cells and macrophages, delayed induction of interferons, weak antibody response, apoptosis of lymphocytes, and hemophagocytosis are some of these tactics. However, there are many points waiting for clarification about the pathogenesis of CCHF. Although the high risk of contagiousness limits research, we need more studies to understand the CCHF pathogenesis better. Here we review the main characteristics of the pathogenesis of CCHF.

Emergence and subsequent functional specialization of kindlins during evolution of cell adhesiveness

PubMed Central

Meller, Julia; Rogozin, Igor B.; Poliakov, Eugenia; Meller, Nahum; Bedanov-Pack, Mark; Plow, Edward F.; Qin, Jun; Podrez, Eugene A.; Byzova, Tatiana V.

2015-01-01

Kindlins are integrin-interacting proteins essential for integrin-mediated cell adhesiveness. In this study, we focused on the evolutionary origin and functional specialization of kindlins as a part of the evolutionary adaptation of cell adhesive machinery. Database searches revealed that many members of the integrin machinery (including talin and integrins) existed before kindlin emergence in evolution. Among the analyzed species, all metazoan lineages—but none of the premetazoans—had at least one kindlin-encoding gene, whereas talin was present in several premetazoan lineages. Kindlin appears to originate from a duplication of the sequence encoding the N-terminal fragment of talin (the talin head domain) with a subsequent insertion of the PH domain of separate origin. Sequence analysis identified a member of the actin filament–associated protein 1 (AFAP1) superfamily as the most likely origin of the kindlin PH domain. The functional divergence between kindlin paralogues was assessed using the sequence swap (chimera) approach. Comparison of kindlin 2 (K2)/kindlin 3 (K3) chimeras revealed that the F2 subdomain, in particular its C-terminal part, is crucial for the differential functional properties of K2 and K3. The presence of this segment enables K2 but not K3 to localize to focal adhesions. Sequence analysis of the C-terminal part of the F2 subdomain of K3 suggests that insertion of a variable glycine-rich sequence in vertebrates contributed to the loss of constitutive K3 targeting to focal adhesions. Thus emergence and subsequent functional specialization of kindlins allowed multicellular organisms to develop additional tissue-specific adaptations of cell adhesiveness. PMID:25540429

Report from the second cytomegalovirus and immunosenescence workshop

PubMed Central

2011-01-01

The Second International Workshop on CMV & Immunosenescence was held in Cambridge, UK, 2-4th December, 2010. The presentations covered four separate sessions: cytomegalovirus and T cell phenotypes; T cell memory frequency, inflation and immunosenescence; cytomegalovirus in aging, mortality and disease states; and the immunobiology of cytomegalovirus-specific T cells and effects of the virus on vaccination. This commentary summarizes the major findings of these presentations and references subsequently published work from the presenter laboratory where appropriate and draws together major themes that were subsequently discussed along with new areas of interest that were highlighted by this discussion. PMID:22035114

The β-catenin signaling pathway stimulates bovine herpesvirus 1 productive infection.

PubMed

Zhu, Liqian; Thunuguntla, Prasanth; Liu, Yilin; Hancock, Morgan; Jones, Clinton

2017-01-01

Bovine herpes virus 1 (BoHV-1), an important bovine pathogen, causes conjunctivitis and disorders in the upper respiratory tract. Following acute infection, BoHV1 establishes life-long latency in sensory neurons. Recent studies demonstrated that viral gene products expressed in trigeminal ganglionic neurons during latency stabilize β-catenin levels, an important signaling molecule that interacts with a family of DNA binding proteins (T-cell factors) and subsequently stimulates transcription. In this study, we provide new evidence demonstrating that BoHV-1 transiently increased β-catenin protein levels in bovine kidney (CRIB) cells, but not in rabbit skin cells. β-catenin dependent transcription was also stimulated by infection of CRIB cells. The β-catenin small molecule inhibitor (iCRT14) significantly reduced the levels of BoHV-1 virus during productive infection of CRIB cells and rabbit skin cells. In summary, these studies suggested the ability of β-catenin to stimulate cell survival and cell cycle regulatory factors enhances productive infection in non-neuronal cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Potential mechanisms for the effects of tea extracts on the attachment, biofilm formation and cell size of Streptococcus mutans.

PubMed

Wang, Yi; Lee, Sui M; Dykes, Gary A

2013-01-01

Tea can inhibit the attachment of Streptococcus mutans to surfaces and subsequent biofilm formation. Five commercial tea extracts were screened for their ability to inhibit attachment and biofilm formation by two strains of S. mutans on glass and hydroxyapatite surfaces. The mechanisms of these effects were investigated using scanning electron microscopy (SEM) and phytochemical screening. The results indicated that extracts of oolong tea most effectively inhibited attachment and extracts of pu-erh tea most effectively inhibited biofilm formation. SEM images showed that the S. mutans cells treated with extracts of oolong tea, or grown in medium containing extracts of pu-erh tea, were coated with tea components and were larger with more rounded shapes. The coatings on the cells consisted of flavonoids, tannins and indolic compounds. The ratio of tannins to simple phenolics in each of the coating samples was ∼3:1. This study suggests potential mechanisms by which tea components may inhibit the attachment and subsequent biofilm formation of S. mutans on tooth surfaces, such as modification of cell surface properties and blocking of the activity of proteins and the structures used by the bacteria to interact with surfaces.

Phosphorylation of a Tyrosine Residue on Zap70 by Lck and Its Subsequent Binding via an SH2 Domain May Be a Key Gatekeeper of T Cell Receptor Signaling In Vivo.

PubMed

Thill, Peter A; Weiss, Arthur; Chakraborty, Arup K

2016-09-15

The initiation of signaling in T lymphocytes in response to the binding of the T cell receptor (TCR) to cognate ligands is a key step in the emergence of adaptive immune responses. Conventional models posit that TCR signaling is initiated by the phosphorylation of receptor-associated immune receptor activation motifs (ITAMs). The cytoplasmic tyrosine kinase Zap70 binds to phosphorylated ITAMs, is subsequently activated, and then propagates downstream signaling. While evidence for such models is provided by experiments with cell lines, in vivo, Zap70 is bound to phosphorylated ITAMs in resting T cells. However, Zap70 is activated only upon TCR binding to cognate ligand. We report the results of computational studies of a new model for the initiation of TCR signaling that incorporates these in vivo observations. Importantly, the new model is shown to allow better and faster TCR discrimination between self-ligands and foreign ligands. The new model is consistent with many past experimental observations, and experiments that could further test the model are proposed. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Cytotoxic Compounds from Aerial Organs of Xanthium strumarium.

PubMed

Ferrer, Janet Piloto; Zampini, Iris Catiana; Cuello, Ana Soledad; Francisco, Marbelis; Romero, Aylema; Valdivia, Dayana; Gonzalez, Maria; Carlos Salas; Lamar, Angel Sanchez; Isla, Maria Inés

2016-03-01

Xanthium strumarium L., the main species of the genus Xanthium, is ubiquitously distributed. The aim of this study was to determine the cytotoxic effect of aerial organs of X strumarium, grown in Cuba, against cancer cell lines and the isolation of compounds potentially responsible for this activity. Initially, an ethanol partitioning procedure yielded the XSE extract that was subsequently fractionated with chloroform resulting in a XSCF fraction. Both, XSE and XSCF fractions exhibited cytotoxic effects on MDA MB-23 1, MCF7, A549 and CT26 cell lines by using the MTT assay. Above all, the XSCF fraction was more active than XSE. For this reason, XSCF was subsequently fractionated by silica gel chromatography and the active fractions submitted to semi-preparative HPLC for isolation of bioactive compounds. Six sub-fractions (SF1 to SF6) were recovered. Sub-fractions 3 and 6 were the most active on each assayed cell line, while sub-fractions 4 and 5 were only active against A549 and CT26 cell lines. In each case, sub-fraction 6 showed the strongest inhibitory effect. The HPLC-DAD fingerprint of sub-fraction 6 showed a single peak that was identified by GC-MS as (-) spathulenol, a sesquiterpene with reported antitumor activity.

Synthesis of silica-PAMAM dendrimer nanoparticles as promising carriers in Neuro blastoma cells.

PubMed

Yesil-Celiktas, Ozlem; Pala, Cansu; Cetin-Uyanikgil, E Oyku; Sevimli-Gur, Canan

2017-02-15

Mesoporous silica carriers are emerging as therapeutic drug delivery systems. The objective of this study was to develop a formulation for synthesizing silica-PAMAM dendrimer hybrid nanoparticles with sol-gel technique. Subsequently, black carrot anthocyanins were encapsulated and investigated for their capability in terms of inhibiting the proliferative effects of neuroblastoma (Neuro 2A). In this context, particle size distributions were ascertained followed by thermal analysis (DSC), scanning electron microscopy and encapsulation efficiency. Subsequently, in vitro release kinetics was determined along with cytotoxicity of empty and anthocyanin doped hybrid nanoparticles. The lowest particle size was 134.8 nm with a zeta potential of +19.78 mV which enhanced electrostatic interaction with the cell membrane in the cytotoxicity analyses. As the anthocyanin content was totally released at the end of 6 days, the cytotoxicity was observed for 134 h, reaching an inhibition of 87.9%. On the other hand, Neuro 2A cells incubated with empty nanoparticles exhibited a high proliferation indicating that hybrid nanoparticles were not toxic to the cells and the inhibitory effect was associated with the anthocyanins. Copyright © 2016 Elsevier Inc. All rights reserved.

[BIOLOGICAL ACTIVITY OF ANTIMICROBIAL PEPTIDES OF ENTEROCOCCUS FAECIUM].

PubMed

Vasilchenko, A S; Rogozhin, E A; Valyshev, A V

2015-01-01

Isolate bacteriocins from Enterococcus faecium metabolites and characterize their effect on cells of Gram positive (Listeria monocytogenes) and Gram negative (Escherichia coli) bacteria. Methods of solid-phase extraction, ion-exchange and reversed phase chromatography were applied for isolation of bacteriocins from cultural medium of bacteria MALDI time-of-flight mass-spectrometry was used for characterization of the obtained preparations. The mechanism of biological effect of peptides was evaluated using DNA-tropic dyes (SYTO 9 and PI) with subsequent registration of fluorescence spectra: Atomic-force microscopy (AFM) was used for characterization of morpho-functional reaction of target cells. Peptide fractions with mass of 1.0 - 3.0 kDa were isolated from enterococci metabolites, that inhibit the growth of indicator microorganisms. E. faecium strain exoproducts were shown to increase membrane permeability during interaction with L. monocytogenes, that results in subsequent detectable disturbance of normal cell morphology of listeria. Alterations of E. coli surface during the effect of purified peptide fraction was detected using AFM. The studies carried out have revealed the effect of bacteriocins of enterococci on microorganisms with various types of cell wall composition and have confirmed the importance of bacterial barrier structure permeability disturbance in the mechanism of antimicrobial effect of enterocins.

Conditioning monitoring by microstructural evaluation of cumulative fatigue damage

NASA Astrophysics Data System (ADS)

Fukuoka, C.; Nakagawa, Y. G.; Lance, J. J.; Pangborn, R. N.

1996-12-01

The objective of this work is to evaluate the damage induced below and above the fatigue limit (Δ σ t =360 MPa) in pressure vessel steels, such as SA508. Fatigue damage was induced in samples taken from an SA508 steel plate by various loading histories in order to examine the influence of prior cyclic loading below the fatigue limit. Cell-to-cell misorientation differences were measured by the selected area diffraction (SAD) method. Surface cracking was also studied by the replication method. Small cracks were observed after precycling both below and above the fatigue limit. It was, however, found that fatigue test bars had a longer lifetime after precycling below the fatigue limit, while precycling above the fatigue limit caused other specimens to fail even when subsequently cycled below the fatigue limit. Cell-to-cell misorientation usually increases with accumulation of fatigue damage, but it was found that the misorientations measured after precycling below the fatigue limit decreased again at the beginning of the subsequent cycling above the fatigue limit. It should be noted that the misorientation at failure was always about 4 to 5 deg, regardless of loading histories. Misorientation showed good correlation with the fatigue lifetime of the samples.

Nuclear microanalysis of platinum and trace elements in cisplatin-resistant human ovarian adenocarcinoma cells

NASA Astrophysics Data System (ADS)

Moretto, P.; Ortega, R.; Llabador, Y.; Simonoff, M.; Bénard, J.; Moretto, Ph.

1995-09-01

Macro-and Micro-PIXE analysis were applied to study the mechanisms of cellular resistance to cisplatin, a chemotherapeutic agent, widely used nowadays for the treatment of ovarian cancer. Two cultured cell lines, a cisplatin-sensitive and a resistant one, were compared for their trace elements content and platinum accumulation following in vitro exposure to the drug. Bulk analysis revealed significant differences in copper and iron content between the two lines. Subsequent individual cell microanalysis permitted us to characterize the response of the different morphological cell types of the resistant line. This study showed that the metabolism of some trace metals in cisplatin-resistant cells could be affected but the exact relationship with the resistant phenotype remains to be determined. From a technical point of view, this experiment demonstrated that an accurate measurement of trace elements could be derived from nuclear microprobe analysis of individual cell.

Invariant NKT Cell Response to Dengue Virus Infection in Human

PubMed Central

Matangkasombut, Ponpan; Chan-in, Wilawan; Opasawaschai, Anunya; Pongchaikul, Pisut; Tangthawornchaikul, Nattaya; Vasanawathana, Sirijitt; Limpitikul, Wannee; Malasit, Prida; Duangchinda, Thaneeya; Screaton, Gavin; Mongkolsapaya, Juthathip

2014-01-01

Background Dengue viral infection is a global health threat without vaccine or specific treatment. The clinical outcome varies from asymptomatic, mild dengue fever (DF) to severe dengue hemorrhagic fever (DHF). While adaptive immune responses were found to be detrimental in the dengue pathogenesis, the roles of earlier innate events remain largely uninvestigated. Invariant natural killer T (iNKT) cells represent innate-like T cells that could dictate subsequent adaptive response but their role in human dengue virus infection is not known. We hypothesized that iNKT cells play a role in human dengue infection. Methods Blood samples from a well-characterized cohort of children with DF, DHF, in comparison to non-dengue febrile illness (OFI) and healthy controls at various time points were studied. iNKT cells activation were analyzed by the expression of CD69 by flow cytometry. Their cytokine production was then analyzed after α-GalCer stimulation. Further, the CD1d expression on monocytes, and CD69 expression on conventional T cells were measured. Results iNKT cells were activated during acute dengue infection. The level of iNKT cell activation associates with the disease severity. Furthermore, these iNKT cells had altered functional response to subsequent ex vivo stimulation with α-GalCer. Moreover, during acute dengue infection, monocytic CD1d expression was also upregulated and conventional T cells also became activated. Conclusion iNKT cells might play an early and critical role in the pathogenesis of severe dengue viral infection in human. Targeting iNKT cells and CD1d serve as a potential therapeutic strategy for severe dengue infection in the future. PMID:24945350

γδT cells but not αβT cells contribute to sepsis-induced white matter injury and motor abnormalities in mice.

PubMed

Zhang, Xiaoli; Rocha-Ferreira, Eridan; Li, Tao; Vontell, Regina; Jabin, Darakhshan; Hua, Sha; Zhou, Kai; Nazmi, Arshed; Albertsson, Anna-Maj; Sobotka, Kristina; Ek, Joakim; Thornton, Claire; Hagberg, Henrik; Mallard, Carina; Leavenworth, Jianmei W; Zhu, Changlian; Wang, Xiaoyang

2017-12-20

Infection and sepsis are associated with brain white matter injury in preterm infants and the subsequent development of cerebral palsy. In the present study, we used a neonatal mouse sepsis-induced white matter injury model to determine the contribution of different T cell subsets (αβT cells and γδT cells) to white matter injury and consequent behavioral changes. C57BL/6J wild-type (WT), T cell receptor (TCR) δ-deficient (Tcrd -/- , lacking γδT cells), and TCRα-deficient (Tcra -/- , lacking αβT cells) mice were administered with lipopolysaccharide (LPS) at postnatal day (PND) 2. Brain myelination was examined at PNDs 12, 26, and 60. Motor function and anxiety-like behavior were evaluated at PND 26 or 30 using DigiGait analysis and an elevated plus maze. White matter development was normal in Tcrd -/- and Tcrα -/- compared to WT mice. LPS exposure induced reductions in white matter tissue volume in WT and Tcrα -/- mice, but not in the Tcrd -/- mice, compared with the saline-treated groups. Neither LPS administration nor the T cell deficiency affected anxiety behavior in these mice as determined with the elevated plus maze. DigiGait analysis revealed motor function deficiency after LPS-induced sepsis in both WT and Tcrα -/- mice, but no such effect was observed in Tcrd -/- mice. Our results suggest that γδT cells but not αβT cells contribute to sepsis-induced white matter injury and subsequent motor function abnormalities in early life. Modulating the activity of γδT cells in the early stages of preterm white matter injury might represent a novel therapeutic strategy for the treatment of perinatal brain injury.

Cationic Surface Charge Combined with Either Vitronectin or Laminin Dictates the Evolution of Human Embryonic Stem Cells/Microcarrier Aggregates and Cell Growth in Agitated Cultures

PubMed Central

Lam, Alan Tin-Lun; Li, Jian; Chen, Allen Kuan-Liang; Reuveny, Shaul

2014-01-01

The expansion of human pluripotent stem cells (hPSC) for biomedical applications generally compels a defined, reliable, and scalable platform. Bioreactors offer a three-dimensional culture environment that relies on the implementation of microcarriers (MC), as supports for cell anchorage and their subsequent growth. Polystyrene microspheres/MC coated with adhesion-promoting extracellular matrix (ECM) protein, vitronectin (VN), or laminin (LN) have been shown to support hPSC expansion in a static environment. However, they are insufficient to promote human embryonic stem cells (hESC) seeding and their expansion in an agitated environment. The present study describes an innovative technology, consisting of a cationic charge that underlies the ECM coatings. By combining poly-L-lysine (PLL) with a coating of ECM protein, cell attachment efficiency and cell spreading are improved, thus enabling seeding under agitation in a serum-free medium. This coating combination also critically enables the subsequent formation and evolution of hPSC/MC aggregates, which ensure cell viability and generate high yields. Aggregate dimensions of at least 300 μm during early cell growth give rise to ≈15-fold expansion at 7 days' culture. Increasing aggregate numbers at a quasi-constant size of ≈300 μm indicates hESC growth within a self-regulating microenvironment. PLL+LN enables cell seeding and aggregate evolution under constant agitation, whereas PLL+VN requires an intermediate 2-day static pause to attain comparable aggregate sizes and correspondingly high expansion yields. The cells' highly reproducible bioresponse to these defined and characterized MC surface properties is universal across multiple cell lines, thus confirming the robustness of this scalable expansion process in a defined environment. PMID:24641164

Induction of viral interference by IPNV-carrier cells on target cells: A cell co-culture study.

PubMed

Parreño, Ricardo; Torres, Susana; Almagro, Lucía; Belló-Pérez, Melissa; Estepa, Amparo; Perez, Luis

2016-11-01

IPNV is a salmonid birnavirus that possesses the ability to establish asymptomatic persistent infections in a number of valuable fish species. The presence of IPNV may interfere with subsequent infection by other viruses. In the present study we show that an IPNV-carrier cell line (EPC IPNV ) can induce an antiviral state in fresh EPC by co-cultivating both cell types in three different ways: a "droplet" culture system, a plastic chamber setup, and a transmembrane (Transwell ® ) system. All three cell co-culture methods were proven useful to study donor/target cell interaction. Naïve EPC cells grown in contact with EPC IPNV cells develop resistance to VHSV superinfection. The transmembrane system seems best suited to examine gene expression in donor and target cells separately. Our findings point to the conclusion that one or more soluble factors produced by the IPNV carrier culture induce the innate immune response within the target cells. This antiviral response is associated to the up-regulation of interferon (ifn) and mx gene expression in target EPC cells. To our knowledge this is the first article describing co-culture systems to study the interplay between virus-carrier cells and naive cells in fish. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Nanomolar concentration of blood-soluble drag-reducing polymer inhibits experimental metastasis of human breast cancer cells

PubMed Central

Ding, Zhijie; Joy, Marion; Kameneva, Marina V; Roy, Partha

2017-01-01

Metastasis is the leading cause of cancer mortality. Extravasation of cancer cells is a critical step of metastasis. We report a novel proof-of-concept study that investigated whether non-toxic blood-soluble chemical agents capable of rheological modification of the near-vessel-wall blood flow can reduce extravasation of tumor cells and subsequent development of metastasis. Using an experimental metastasis model, we demonstrated that systemic administration of nanomolar concentrations of so-called drag-reducing polymer dramatically impeded extravasation and development of pulmonary metastasis of breast cancer cells in mice. This is the first proof-of-principle study to directly demonstrate physical/rheological, as opposed to chemical, way to prevent cancer cells from extravasation and developing metastasis and, thus, it opens the possibility of a new direction of adjuvant interventional approach in cancer. PMID:28280386

Environmentally Induced Transgenerational Epigenetic Reprogramming of Primordial Germ Cells and the Subsequent Germ Line

PubMed Central

Skinner, Michael K.; Haque, Carlos Guerrero-Bosagna M.; Nilsson, Eric; Bhandari, Ramji; McCarrey, John R.

2013-01-01

A number of environmental factors (e.g. toxicants) have been shown to promote the epigenetic transgenerational inheritance of disease and phenotypic variation. Transgenerational inheritance requires the germline transmission of altered epigenetic information between generations in the absence of direct environmental exposures. The primary periods for epigenetic programming of the germ line are those associated with primordial germ cell development and subsequent fetal germline development. The current study examined the actions of an agricultural fungicide vinclozolin on gestating female (F0 generation) progeny in regards to the primordial germ cell (PGC) epigenetic reprogramming of the F3 generation (i.e. great-grandchildren). The F3 generation germline transcriptome and epigenome (DNA methylation) were altered transgenerationally. Interestingly, disruptions in DNA methylation patterns and altered transcriptomes were distinct between germ cells at the onset of gonadal sex determination at embryonic day 13 (E13) and after cord formation in the testis at embryonic day 16 (E16). A larger number of DNA methylation abnormalities (epimutations) and transcriptional alterations were observed in the E13 germ cells than in the E16 germ cells. These observations indicate that altered transgenerational epigenetic reprogramming and function of the male germline is a component of vinclozolin induced epigenetic transgenerational inheritance of disease. Insights into the molecular control of germline transmitted epigenetic inheritance are provided. PMID:23869203

Effect of Irrigation Time of Antiseptic Solutions on Bone Cell Viability and Growth Factor Release.

PubMed

Sawada, Kosaku; Nakahara, Ken; Haga-Tsujimura, Maiko; Fujioka-Kobayashi, Masako; Iizuka, Tateyuki; Miron, Richard J

2018-03-01

Antiseptic solutions are commonly utilized to treat local infection in the oral and maxillofacial region. However, surrounding vital bone is also exposed to antiseptic agents during irrigation and may have a potential negative impact on bone survival. The aim of the present study was therefore to investigate the effect of rinsing time with various antiseptic solutions on bone cell viability, as well as their subsequent release of growth factors important for bone regeneration. The bone samples collected from porcine mandible were rinsed in the following commonly utilized antiseptic solutions; povidone-iodine (0.5%), chlorhexidine digluconate (CHX, 0.2%), hydrogen peroxide (1%), and sodium hypochlorite (0.25%) for 1, 5, 10, 20, 30, or 60 minutes and assessed for cell viability and release of growth factors including vascular endothelial growth factor, transforming growth factor beta 1, bone morphogenetic protein 2, receptor activator of nuclear factor kappa-B ligand, and interleukin-1 beta by enzyme-linked immunosorbent assay. It was found in all the tested groups that the long exposure of any of the tested antiseptic solutions drastically promoted higher cell death. Sodium hypochlorite demonstrated the significantly highest cell death and at all time points. Interestingly, bone cell viability was highest in the CHX group post short-term rinsing of 1, 5, or 10 minutes when compared with the other 4 tested groups. A similar trend was also observed in subsequent growth factor release. The present study demonstrated that of the 4 tested antiseptic solutions, short-term CHX rinsing (ideally within 1 minute) favored bone cell viability and growth factor release. Clinical protocols should be adapted accordingly.

PLGA-CTAB curcumin nanoparticles: Fabrication, characterization and molecular basis of anticancer activity in triple negative breast cancer cell lines (MDA-MB-231 cells).

PubMed

Meena, Ramovatar; Kumar, Sumit; Kumar, Raj; Gaharwar, Usha Singh; Rajamani, Paulraj

2017-10-01

Triple-negative breast cancers (TNBC) are aggressive cancers, which do not control by hormonal therapy or therapies that target HER-2 receptors. Curcumin (Cur) has shown cytotoxic effects in multiple cancer cell lines. However, its medical uses remain limited due to low aqueous solubility and poor bioavailability. Therefore, present study was aimed to fabricate the small positive charge curcumin nanoparticles (CN) by nanoprecipitation methods using PLGA and CTAB, and to evaluate its anticancer efficacy and underlying the mechanism in triple negative breast cancer cell lines (MDA-MB-231 cells). In in-vitro drug release assay, Cur was released from CN by flicking diffusion and anomalous transport process. CN showed a higher cellular incorporation than free Cur resulted in higher cytotoxicity. Checking the anticancer activity at the molecular level, Cur has shown to induce the reactive oxygen species production that subsequently causes the DNA damage and resulting in p38-MAPK activation. The p38-MAPK induce the expression of p16 /INKK4a , p21 /waf1/cip1 and p53 resulting in a reduction in the level of CDK2, CDK4, cyclin D1 and cyclin E and subsequently cell cycle arrest at G1/S and G2/M phase. It also reduces the expression of DNA repair gene, i.e. BRCA1, BRCA2, Rad51, Rad50, Mre11 and NBS1 resulting in apoptosis induction due to persistent DNA damage. This study presents an effective delivery of curcumin in TNBC cancer cells and it could open the new frontiers in clinical cancer chemotherapy. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Molecular circuitry of stem cell fate in skeletal muscle regeneration, ageing, and disease

PubMed Central

Almada, Albert E.; Wagers, Amy J.

2016-01-01

Satellite cells are adult myogenic stem cells that function to repair damaged muscle. The enduring capacity for muscle regeneration requires efficient satellite cell expansion after injury, differentiation to produce myoblasts that can reconstitute damaged fibers, and self-renewal to replenish the muscle stem cell pool for subsequent rounds of injury and repair. Emerging studies indicate that misregulations of satellite cell fate and function contribute to age-associated muscle dysfunction and influence the severity of muscle diseases, including Duchenne Muscular Dystrophy (DMD). It has also become apparent that satellite cell fate during muscle regeneration, aging, and in the context of DMD is governed by an intricate network of intrinsic and extrinsic regulators. Targeted manipulation of this network may offer unique opportunities for muscle regenerative medicine. PMID:26956195

Carbon-dependent chromate toxicity mechanism in an environmental Arthrobacter isolate.

PubMed

Field, Erin K; Blaskovich, John P; Peyton, Brent M; Gerlach, Robin

2018-05-12

Arthrobacter spp. are widespread in soil systems and well-known for their Cr(VI) reduction capabilities making them attractive candidates for in situ bioremediation efforts. Cellulose drives carbon flow in soil systems; yet, most laboratory studies evaluate Arthrobacter-Cr(VI) interactions solely with nutrient-rich media or glucose. This study aims to determine how various cellulose degradation products and biostimulation substrates influence Cr(VI) toxicity, reduction, and microbial growth of an environmental Arthrobacter sp. isolate. Laboratory culture-based studies suggest there is a carbon-dependent Cr(VI) toxicity mechanism that affects subsequent Cr(VI) reduction by strain LLW01. Strain LLW01 could only grow in the presence of, and reduce, 50 μM Cr(VI) when glucose or lactate were provided. Compared to lactate, Cr(VI) was at least 30-fold and 10-fold more toxic when ethanol or butyrate was the sole carbon source, respectively. The addition of sulfate mitigated toxicity somewhat, but had no effect on the extent of Cr(VI) reduction. Cell viability studies indicated that a small fraction of cells were viable after 8 days suggesting cell growth and subsequent Cr(VI) reduction may resume. These results suggest when designing bioremediation strategies with Arthrobacter spp. such as strain LLW01, carbon sources such as glucose and lactate should be considered over ethanol and butyrate. Copyright © 2018 Elsevier B.V. All rights reserved.

Viability of ligaments after freezing: an experimental study in a rabbit model.

PubMed

Frank, C; Edwards, P; McDonald, D; Bodie, D; Sabiston, P

1988-01-01

Our purpose in this study was to assess ligament fibroblast viability after freezing by quantifying the subsequent ability of fibroblasts to synthesize collagen in vitro. Both medial collateral ligament (MCL) complexes from 40 adolescent rabbits were studied. Collagen production was determined by in vitro incubation of ligaments in 3H-proline (a collagen precursor) and subsequent analysis of 3H-hydroxyproline (a marker of newly synthesized collagen). Autoradiographs determined the distributions of ligament cell activity. All right MCL complexes served as fresh controls, providing a baseline of collagen production. Each left MCL was assigned to an experimental group and was either incubated fresh (10 animals); "killed" by drying, multiple freeze thawing, or cycloheximide (six animals); or slowly frozen at -70 degrees C without cryoprotection (24 animals). Collagen production of rapidly thawed ligaments was studied by proline incubation at 1 day, 9 days, or 6 weeks after freezing and was compared with that of contralateral fresh controls. Results demonstrate that some cells in the substance of these rabbit ligaments retained the ability to synthesize collagen in vitro after being frozen for up to 6 weeks. Mean collagen production of frozen ligaments was decreased, but tests of mean and median values as well as ratios were statistically similar to fresh contralateral ligaments in all animals. This postfreezing ligament cell survival and collagen production after -70 degrees C storage may have implications for ligament transplantation.

Characterizing and Targeting Bone Marrow-Derived Inflammatory Cells in Driving the Malignancy and Progression of Childhood Astrocytic Brain Tumors

DTIC Science & Technology

2016-11-01

importance of myeloid derived ID2/VEGFR2 signaling in low-grade to high-grade glioma transformation . 15. SUBJECT TERMS Glioma, Pediatric, bone-marrow...derived-cells, endothelial, mesenchymal, myeloid, hematopoietic, differentiation, malignant, transformation , VEGFR2, ID2. 16. SECURITY CLASSIFICATION OF...subsequent recruitment, in order to suppress the malignant transformation of gliomas. In this project, we have initiated the study of BMDCs with RCAS and

In vitro anti-breast cancer activity of ethanolic extract of Wrightia tomentosa: role of pro-apoptotic effects of oleanolic acid and urosolic acid.

PubMed

Chakravarti, Bandana; Maurya, Ranjani; Siddiqui, Jawed Akhtar; Bid, Hemant Kumar; Rajendran, S M; Yadav, Prem P; Konwar, Rituraj

2012-06-26

Wrightia tomentosa Roem. & Schult. (Apocynaceae) is known in the traditional medicine for anti-cancer activity along with other broad indications like snake and scorpion bites, renal complications, menstrual disorders etc. However, the anti-cancer activity of this plant or its constituents has never been studied systematically in any cancer types so far. To evaluate the anti-cancer activities of the ethanolic extract of W. tomentosa and identified constituent active molecule(s) against breast cancer. Powdered leaves of W. tomentosa were extracted with ethanol. The ethanolic extract, subsequent hexane fractions and fraction F-4 of W. tomentosa were tested for its anti-proliferative and pro-apoptotic effects in breast cancer cells MCF-7 and MDA-MB-231. The ethanolic extract, subsequent hexane fractions and fraction F-4 of W. tomentosa inhibited the proliferation of human breast cancer cell lines, MCF-7 and MDA-MB-231. The fraction F-4 obtained from hexane fraction inhibited proliferation of MCF-7 and MDA-MB-231 cells in concentration and time dependent manner with IC₅₀ of 50 μg/ml and 30 μg/ml for 24 h, 28 μg/ml and 22 μg/ml for 48 h and 25 μg/ml and 20 μg/ml for 72 h respectively. The fraction F-4 induced G1 cell cycle arrest, reactive oxygen species (ROS) generation, loss of mitochondrial membrane potential and subsequent apoptosis. Apoptosis is indicated in terms of increased Bax/Bcl-2 ratio, enhanced Annexin-V positivity, caspase 8 activation and DNA fragmentation. The active molecule isolated from fraction F-4, oleanolic acid and urosolic acid inhibited cell proliferation of MCF-7 and MDA-MB-231 cells at IC₅₀ value of 7.5 μM and 7.0 μM respectively, whereas there is devoid of significant cell inhibiting activity in non-cancer originated cells, HEK-293. In both MCF-7 and MDA-MB-231, oleanolic acid and urosolic acid induced cell cycle arrest and apoptosis as indicated by significant increase in Annexin-V positive apoptotic cell counts. Our results suggest that W. tomentosa extracts has significant anti-cancer activity against breast cancer cells due to induction of apoptosis pathway. Olenolic and urosolic acid are important constituent molecules in the extract responsible for anti-cancer activity of W. tomentosa.

A photoelectrochemical platform for the capture and release of rare single cells.

PubMed

Parker, Stephen G; Yang, Ying; Ciampi, Simone; Gupta, Bakul; Kimpton, Kathleen; Mansfeld, Friederike M; Kavallaris, Maria; Gaus, Katharina; Gooding, J Justin

2018-06-12

For many normal and aberrant cell behaviours, it is important to understand the origin of cellular heterogeneity. Although powerful methods for studying cell heterogeneity have emerged, they are more suitable for common rather than rare cells. Exploring the heterogeneity of rare single cells is challenging because these rare cells must be first pre-concentrated and undergo analysis prior to classification and expansion. Here, a versatile capture & release platform consisting of an antibody-modified and electrochemically cleavable semiconducting silicon surface for release of individual cells of interest is presented. The captured cells can be interrogated microscopically and tested for drug responsiveness prior to release and recovery. The capture & release strategy was applied to identify rare tumour cells from whole blood, monitor the uptake of, and response to, doxorubicin and subsequently select cells for single-cell gene expression based on their response to the doxorubicin.

Tunable Single-Cell Extraction for Molecular Analyses.

PubMed

Guillaume-Gentil, Orane; Grindberg, Rashel V; Kooger, Romain; Dorwling-Carter, Livie; Martinez, Vincent; Ossola, Dario; Pilhofer, Martin; Zambelli, Tomaso; Vorholt, Julia A

2016-07-14

Because of cellular heterogeneity, the analysis of endogenous molecules from single cells is of significant interest and has major implications. While micromanipulation or cell sorting followed by cell lysis is already used for subsequent molecular examinations, approaches to directly extract the content of living cells remain a challenging but promising alternative to achieving non-destructive sampling and cell-context preservation. Here, we demonstrate the quantitative extraction from single cells with spatiotemporal control using fluidic force microscopy. We further present a comprehensive analysis of the soluble molecules withdrawn from the cytoplasm or the nucleus, including the detection of enzyme activities and transcript abundances. This approach has uncovered the ability of cells to withstand extraction of up to several picoliters and opens opportunities to study cellular dynamics and cell-cell communication under physiological conditions at the single-cell level. Copyright © 2016 Elsevier Inc. All rights reserved.

Generation of inner ear sensory cells from bone marrow-derived human mesenchymal stem cells.

PubMed

Durán Alonso, M Beatriz; Feijoo-Redondo, Ana; Conde de Felipe, Magnolia; Carnicero, Estela; García, Ana Sánchez; García-Sancho, Javier; Rivolta, Marcelo N; Giráldez, Fernando; Schimmang, Thomas

2012-11-01

Hearing loss is the most common sensory disorder in humans, its main cause being the loss of cochlear hair cells. We studied the potential of human mesenchymal stem cells (hMSCs) to differentiate towards hair cells and auditory neurons. hMSCs were first differentiated to neural progenitors and subsequently to hair cell- or auditory neuron-like cells using in vitro culture methods. Differentiation of hMSCs to an intermediate neural progenitor stage was critical for obtaining inner ear sensory lineages. hMSCs generated hair cell-like cells only when neural progenitors derived from nonadherent hMSC cultures grown in serum-free medium were exposed to EGF and retinoic acid. Auditory neuron-like cells were obtained when treated with retinoic acid, and in the presence of defined growth factor combinations containing Sonic Hedgehog. The results show the potential of hMSCs to give rise to inner ear sensory cells.

Sensitization of cerebral tissue in nude mice with photodynamic therapy induces ADAM17/TACE and promotes glioma cell invasion

PubMed Central

Zheng, Xuguang; Jiang, Feng; Katakowski, Mark; Zhang, Xuepeng; Jiang, Hao; Zhang, Zheng Gang; Chopp, Michael

2008-01-01

In the present study, we tested the hypothesis that a mild cerebral tissue injury promotes subsequent glioma invasion via activation of the ADAM17-EGFR-PI3K-Akt pathway. Mild injury was induced by Photodynamic therapy (PDT), which employs tissue-penetrating laser light exposure following systemic administration of a tumor-localizing photosensitizer. Athymic nude mice were treated with sublethal PDT (80J/cm2 with 2mg/kg Photofrin). Hypoxic stress and ADAM17-EGFR-PI3K-Akt were measured using Western blot and immunostaining. Additional groups with/without pro-sublethal PDT were subsequently implanted with U87 glioma tumor cell. Tumor invasion and ADAM17-EGFR-PI3K-Akt pathway in tumor area were measured. After a sublethal dose of PDT, HIF-1α expression was increased by a factor of three in PDT-treated normal brain tissue compared to contralateral control brain tissue. PDT-treated brain tissue exhibited a significant increase in ADAM17, p-EGFR, p-Akt expression compared to non-treated tissue. ADAM17 positive area significantly increased from 1.78% to 10.89%. The percentage of p-EGFR and p-Akt positive cells significantly increased from 9.50% and 14.50% to 21.31% and 32.29%,respectively, PDT treatment significantly increased subsequent implanted U87 glioma cell invasion by 3.68-fold and increased ADAM17, EGFR, p-EGFR, Akt, p-Akt expression by 178%, 43.9%,152.7%, 89.6%,and 164.2%, respectively, compared to control group. Our data showed that a sublethal sensitization of cerebral tissue with PDT significantly increased U87 cell invasion in nude mice, and that glioma cell invasion is highly correlated with activation of the ADAM17-EGFR-PI3K-Akt pathway (r=0.928, 0.775, 0.870, 0.872, and 0.883, respectively), most likely via HIF-1α. PMID:18358600

Separation of somatic and germ cells is required to establish primate spermatogonial cultures.

PubMed

Langenstroth, Daniel; Kossack, Nina; Westernströer, Birgit; Wistuba, Joachim; Behr, Rüdiger; Gromoll, Jörg; Schlatt, Stefan

2014-09-01

Can primate spermatogonial cultures be optimized by application of separation steps and well defined culture conditions? We identified the cell fraction which provides the best source for primate spermatogonia when prolonged culture is desired. Man and marmoset show similar characteristics in regard to germ cell development and function. Several protocols for isolation and culture of human testis-derived germline stem cells have been described. Subsequent analysis revealed doubts on the germline origin of these cells and characterized them as mesenchymal stem cells or fibroblasts. Studies using marmosets as preclinical model confirmed that the published isolation protocols did not lead to propagation of germline cells. Testicular cells derived from nine adult marmoset monkeys (Callithrix jacchus) were cultured for 1, 3, 6 and 11 days and consecutively analyzed for the presence of spermatogonia, differentiating germ cells and testicular somatic cells. Testicular tissue of nine adult marmoset monkeys was enzymatically dissociated and subjected to two different cell culture approaches. In the first approach all cells were kept in the same dish (non-separate culture, n = 5). In the second approach the supernatant cells were transferred into a new dish 24 h after seeding and subsequently supernatant and attached cells were cultured separately (separate culture, n = 4). Real-time quantitative PCR and immunofluorescence were used to analyze the expression of reliable germ cell and somatic markers throughout the culture period. Germ cell transplantation assays and subsequent wholemount analyses were performed to functionally evaluate the colonization of spermatogonial cells. This is the first report revealing an efficient isolation and culture of putative marmoset spermatogonial stem cells with colonization ability. Our results indicate that a separation of spermatogonia from testicular somatic cells is a crucial step during cell preparation. We identified the overgrowth of more rapidly expanding somatic cells to be a major problem when establishing spermatogonial cultures. Initiating germ cell cultures from the supernatant and maintaining germ cells in suspension cultures minimized the somatic cell contamination and provided enriched germ cell fractions which displayed after 11 days of culture a significantly higher expression of germ cell markers genes (DDX-4, MAGE A-4; P < 0.05) compared with separately cultured attached cells. Additionally, germ cell transplantation experiments demonstrated a significantly higher absolute number of cells with colonization ability (P < 0.001) in supernatant cells after 11 days of separate culture. This study presents a relevant aspect for the successful setup of spermatogonial cultures but provides limited data regarding the question of whether the long-term maintenance of spermatogonia can be achieved. Transfer of these preclinical data to man may require modifications of the protocol. Spermatogonial cultures from rodents have become important and innovative tools for basic and applied research in reproductive biology and veterinary medicine. It is expected that spermatogonia-based strategies will be transformed into clinical applications for the treatment of male infertility. Our data in the marmoset monkey may be highly relevant to establish spermatogonial cultures of human testes. Funding was provided by the DFG-Research Unit FOR 1041 Germ Cell Potential (SCHL394/11-2) and by the Graduate Program Cell Dynamics and Disease (CEDAD) together with the International Max Planck Research School - Molecular Biomedicine (IMPRS-MBM). The authors declare that there is no conflict of interest. Not applicable. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Emulsified isoflurane treatment inhibits the cell cycle and respiration of human bronchial epithelial 16HBE cells in a p53-independent manner.

PubMed

Yang, Hui; Deng, Jia; Jiang, Yingying; Chen, Jiao; Zeng, Xianzheng; He, Zhiyang; Jiang, Xiaojuan; Li, Zhuoning; Jiang, Chunling

2016-07-01

Emulsified isoflurane (EIso), as a result of its rapid anesthetic induction, recovery and convenience, is widely used as a novel intravenous general anesthetic. Treatment with EIso can reduce injuries caused by ischemia/reperfusion (I/R) to organs, including the heart, lung and liver, without knowing understanding the molecular mechanism. The present study hypothesized that treatment with EIso can affect the physiological processes of human lung bronchial epithelial cells (16HBE) prior to I/R. To test this hypothesis, the present study first constructed stable p53 knockdown and synthesis of cytochrome c oxidase (SCO)2 knockdown 16HBE cells. The above cells were subsequently treated with EIso at a concentration of 0.1 and 0.2% for 24 h. The relevant concentration of fat emulsion was used as a negative control. The expression levels of p53, p21, SCO1, SCO2 and Tp53‑induced glycolysis and apoptosis regulator (TIGAR) were detected by reverse transcription‑quantitative polymerase chain reaction and western blotting. Subsequently, the cell proliferation, respiration and glycolysis were investigated. The results revealed that EIso treatment significantly decreased the transcription of TIGAR, SCO1 and SCO2, and increased the transcription of p21, which are all p53 target genes, in a p53-independent manner. The cell cycle was inhibited by arresting cells at the G0/G1 phase. Respiration was reduced, which caused a decrease in oxygen consumption and the accumulation of lactate and reactive oxygen species. Taken together, EIso treatment inhibited the proliferation and respiration, and promoted glycolysis in 16HBE cells. This regulatory pathway may represent a protective mechanism of EIso treatment by inhibiting cell growth and decreasing the oxygen consumption from I/R.

Knockdown of stromal interaction molecule 1 inhibits proliferation of colorectal cancer cells by inducing apoptosis.

PubMed

Yang, Dong; Dai, Xiaoyu; Li, Keqiang; Xie, Yangyang; Zhao, Jianpei; Dong, Mingjun; Yu, Hua; Kong, Zhenfang

2018-06-01

Stromal interaction molecule 1 (STIM1) is an endoplasmic reticulum Ca 2+ sensor which has been reported to be overexpressed in numerous types of cancer, and is involved in the cell proliferation, invasion, migration and metastasis frequently observed in cancer. However, the role of STIM1 in colorectal cancer (CRC) remains unknown. The purpose of the present study was to investigate the effect of STIM1 in human CRC. The expression of STIM1 was specifically knocked down using lentivirus-mediated small hairpin RNA (shRNA) interference techniques in the CRC cell lines HCT116 and SW1116. Subsequently, the efficiency of infection was confirmed using green fluorescent protein (GFP)-positive signals. The knockdown efficiency was further determined using the reverse transcription-quantitative polymerase chain reaction and western blotting analysis. As a result, CRC cell lines with STIM1 silenced were successfully constructed and subsequently employed in a series of cell function assays. Knockdown of STIM1 significantly suppressed cell proliferation and colony formation, as revealed by an MTT and colony formation assay. Furthermore, it was identified that STIM1 silencing may promote cell apoptosis through the induction of mitochondria-associated apoptosis, as was identified by increased expression levels of B-cell lymphoma 2 (Bcl-2)-associated death promoter, Bcl-2-associated X protein and poly(ADP-ribose) polymerase cleavage. Therefore, STIM1 may serve a critical role in the progression of CRC by regulating cell proliferation and apoptosis, which may provide a potential therapeutic target for the treatment of CRC.

Microgrooved Polymer Substrates Promote Collective Cell Migration To Accelerate Fracture Healing in an in Vitro Model.

PubMed

Zhang, Qing; Dong, Hua; Li, Yuli; Zhu, Ye; Zeng, Lei; Gao, Huichang; Yuan, Bo; Chen, Xiaofeng; Mao, Chuanbin

2015-10-21

Surface topography can affect cell adhesion, morphology, polarity, cytoskeleton organization, and osteogenesis. However, little is known about the effect of topography on the fracture healing in repairing nonunion and large bone defects. Microgrooved topography on the surface of bone implants may promote cell migration into the fracture gap to accelerate fracture healing. To prove this hypothesis, we used an in vitro fracture (wound) healing assay on the microgrooved polycaprolactone substrates to study the effect of microgroove widths and depths on the osteoblast-like cell (MG-63) migration and the subsequent healing. We found that the microgrooved substrates promoted MG-63 cells to migrate collectively into the wound gap, which serves as a fracture model, along the grooves and ridges as compared with the flat substrates. Moreover, the groove widths did not show obvious influence on the wound healing whereas the smaller groove depths tended to favor the collective cell migration and thus subsequent healing. The microgrooved substrates accelerated the wound healing by facilitating the collective cell migration into the wound gaps but not by promoting the cell proliferation. Furthermore, microgrooves were also found to promote the migration of human mesenchymal stem cells (hMSCs) to heal the fracture model. Though osteogenic differentiation of hMSCs was not improved on the microgrooved substrate, collagen I and minerals deposited by hMSCs were organized in a way similar to those in the extracellular matrix of natural bone. These findings suggest the necessity in using microgrooved implants in enhancing fracture healing in bone repair.

A framework for evaluating developmental defects at the cellular level: An example from ten maize anther mutants using morphological and molecular data.

PubMed

Egger, Rachel L; Walbot, Virginia

2016-11-01

In seed plants, anthers are critical for sexual reproduction, because they foster both meiosis and subsequent pollen development of male germinal cells. Male-sterile mutants are analyzed to define steps in anther development. Historically the major topics in these studies are meiotic arrest and post-meiotic gametophyte failure, while relatively few studies focus on pre-meiotic defects of anther somatic cells. Utilizing morphometric analysis we demonstrate that pre-meiotic mutants can be impaired in anticlinal or periclinal cell division patterns and that final cell number in the pre-meiotic anther lobe is independent of cell number changes of individual differentiated somatic cell types. Data derived from microarrays and from cell wall NMR analyses allow us to further refine our understanding of the onset of phenotypes. Collectively the data highlight that even minor deviations from the correct spatiotemporal pattern of somatic cell proliferation can result in male sterility in Zea mays. Copyright © 2016 Elsevier Inc. All rights reserved.

Endocrine disrupting chemicals affect the adipogenic differentiation of mesenchymal stem cells in distinct ontogenetic windows

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

Biemann, Ronald, E-mail: ronald.biemann@medizin.uni-halle.de; Navarrete Santos, Anne; Navarrete Santos, Alexander

Highlights: Black-Right-Pointing-Pointer Endocrine disrupting chemicals affect adipogenesis in mesenchymal stem cells (MSC). Black-Right-Pointing-Pointer The adipogenic impact depends strongly on the window of exposure. Black-Right-Pointing-Pointer Bisphenol A reduces the potential of MSC to differentiate into adipocytes. Black-Right-Pointing-Pointer DEHP and TBT trigger the adipogenic differentiation of mesenchymal stem cells. Black-Right-Pointing-Pointer BPA, DEHP and TBT did not affect adipogenesis in embryonic stem cells. -- Abstract: Endocrine disrupting chemicals (EDC) like bisphenol A (BPA), bis(2-ethylhexyl)phthalate (DEHP) and tributyltin (TBT) are ubiquitously present in the environment and in human tissues. They bind to nuclear hormone receptors and affect cellular and developmental processes. In this study,more » we show that BPA, DEHP and TBT affect the adipogenic differentiation of murine mesenchymal stem cells (MSC, C3H/10T1/2) in a concentration-, stage- and compound-specific manner. C3H/10T1/2 cells and embryonic stem cells (CGR8) were exposed to BPA, DEHP or TBT at different stages of cell determination and differentiation (undifferentiated growth, adipogenic induction and terminal adipogenic differentiation). The final amount of differentiated adipocytes, cellular triglyceride content and mRNA expression of adipogenic marker genes (adiponectin, FABP4, PPAR{gamma}2, LPL) were quantified and compared with corresponding unexposed cells. BPA (10 {mu}M) decreased subsequent adipogenic differentiation of MSC, when cells were exposed during undifferentiated growth. In contrast, DEHP (100 {mu}M) during the hormonal induction period, and TBT (100 nM) in all investigated stages, enhanced adipogenesis. Importantly, exposure of undifferentiated murine embryonic stem cells did not show any effect of the investigated EDC on subsequent adipogenic differentiation.« less

MicroRNA-7 Promotes Glycolysis to Protect against 1-Methyl-4-phenylpyridinium-induced Cell Death.

PubMed

Chaudhuri, Amrita Datta; Kabaria, Savan; Choi, Doo Chul; Mouradian, M Maral; Junn, Eunsung

2015-05-08

Parkinson disease is associated with decreased activity of the mitochondrial electron transport chain. This defect can be recapitulated in vitro by challenging dopaminergic cells with 1-methyl-4-phenylpyridinium (MPP(+)), a neurotoxin that inhibits complex I of electron transport chain. Consequently, oxidative phosphorylation is blocked, and cells become dependent on glycolysis for ATP production. Therefore, increasing the rate of glycolysis might help cells to produce more ATP to meet their energy demands. In the present study, we show that microRNA-7, a non-coding RNA that protects dopaminergic neuronal cells against MPP(+)-induced cell death, promotes glycolysis in dopaminergic SH-SY5Y and differentiated human neural progenitor ReNcell VM cells, as evidenced by increased ATP production, glucose consumption, and lactic acid production. Through a series of experiments, we demonstrate that targeted repression of RelA by microRNA-7, as well as subsequent increase in the neuronal glucose transporter 3 (Glut3), underlies this glycolysis-promoting effect. Consistently, silencing Glut3 expression diminishes the protective effect of microRNA-7 against MPP(+). Further, microRNA-7 fails to prevent MPP(+)-induced cell death when SH-SY5Y cells are cultured in a low glucose medium, as well as when differentiated ReNcell VM cells or primary mouse neurons are treated with the hexokinase inhibitor, 2-deoxy-d-glucose, indicating that a functional glycolytic pathway is required for this protective effect. In conclusion, microRNA-7, by down-regulating RelA, augments Glut3 expression, promotes glycolysis, and subsequently prevents MPP(+)-induced cell death. This protective effect of microRNA-7 could be exploited to correct the defects in oxidative phosphorylation in Parkinson disease. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Fabrication of viable and functional pre-vascularized modular bone tissues by coculturing MSCs and HUVECs on microcarriers in spinner flasks.

PubMed

Zhang, Songjie; Zhou, Min; Ye, Zhaoyang; Zhou, Yan; Tan, Wen-Song

2017-08-01

Slow vascularization often impedes the viability and function of engineered bone replacements. Prevascularization is a promising way to solve this problem. In this study, a new process was developed by integrating microcarrier culture and coculture to fabricate pre-vascularized bone microtissues with mesenchymal stem cells (MSCs) and human umbilical vein endothelial cells (HUVECs). Initially, coculture medium and cell ratio between MSCs and HUVECs were optimized in tissue culture plates concerning cell proliferation, osteogenesis and angiogenesis. Subsequently, cells were seeded onto CultiSpher S microcarriers in spinner flasks and subjected to a two-stage (proliferative-osteogenic) culture process for four weeks. Both cells proliferated and functioned well in chosen medium and a 1 : 1 ratio between MSCs and HUVECs was chosen for better angiogenesis. After four weeks of culture in spinner flasks, the microtissues were formed with high cellularity, evenly distributed cells and tube formation ability. While coculture with HUVECs exerted an inhibitory effect on osteogenic differentiation of MSCs, with downregulated alkaline phosphatase activity, mineralization and gene expression of COLI, RUNX2 and OCN, this could be attenuated by employing a delayed seeding strategy of HUVECs against MSCs during the microtissue fabrication process. Collectively, this work established an effective method to fabricate pre-vascularized bone microtissues, which would lay a solid foundation for subsequent development of vascularized tissue grafts for bone regeneration. Copyright © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Collagen Self-Assembly on Orthopedic Magnesium Biomaterials Surface and Subsequent Bone Cell Attachment

PubMed Central

Zhao, Nan; Zhu, Donghui

2014-01-01

Magnesium (Mg) biomaterials are a new generation of biodegradable materials and have promising potential for orthopedic applications. After implantation in bone tissues, these materials will directly interact with extracellular matrix (ECM) biomolecules and bone cells. Type I collagen, the major component of bone ECM, forms the architecture scaffold that provides physical support for bone cell attachment. However, it is still unknown how Mg substrate affects collagen assembly on top of it as well as subsequent cell attachment and growth. Here, we studied the effects of collagen monomer concentration, pH, assembly time, and surface roughness of two Mg materials (pure Mg and AZ31) on collagen fibril formation. Results showed that formation of fibrils would not initiate until the monomer concentration reached a certain level depending on the type of Mg material. The thickness of collagen fibril increased with the increase of assembly time. The structures of collagen fibrils formed on semi-rough surfaces of Mg materials have a high similarity to that of native bone collagen. Next, cell attachment and growth after collagen assembly were examined. Materials with rough surface showed higher collagen adsorption but compromised bone cell attachment. Interestingly, surface roughness and collagen structure did not affect cell growth on AZ31 for up to a week. Findings from this work provide some insightful information on Mg-tissue interaction at the interface and guidance for future surface modifications of Mg biomaterials. PMID:25303459

Columnar cell change with atypia (flat epithelial atypia) on breast core biopsy-outcomes following open excision.

PubMed

Biggar, Magdalena A; Kerr, Kris M; Erzetich, Lisa M; Bennett, Ian C

2012-01-01

Columnar cell change with atypia (CCCA) is a relatively recently recognized pathologic breast entity considered to be a risk factor for subsequent development of breast carcinoma. The aim of this study was to investigate the significance of finding CCCA on breast core biopsy, by establishing the frequency of other breast pathology on subsequently performed surgical excision specimens. All cases with CCCA as the most advanced lesion on core biopsy were reviewed. After excision, another advanced proliferative lesion was identified in 17 (33%) patients, including three patients (6%) with in situ or invasive carcinoma. An additional five patients (10%) were concurrently diagnosed with primary breast carcinoma at other sites. These findings indicate that when CCCA is found on core biopsy, open surgical biopsy of the relevant area should be performed and that workup of both breasts should be undertaken to exclude coexistent breast carcinoma at alternative sites. © 2012 Wiley Periodicals, Inc.

Extranodal posttransplant plasmacytic hyperplasia with subsequent posttransplant plasmacytic malignancy: six-year interval case report and review of the literature.

PubMed

Dunphy, Cherie H; Galambos, Csaba; Polski, Jacek M; Evans, H Lance; Gardner, Laura J; Grosso, Leonard E; Montone, Kathleen T

2002-03-01

Posttransplant lymphoproliferative disorders (PTLDs) represent a morphologic, immunophenotypic, and genotypic spectrum of disease. Most recently, Knowles et al divided PTLDs into 3 distinct categories: (1) plasmacytic hyperplasia, (2) polymorphic B-cell hyperplasia and polymorphic B-cell lymphoma, and (3) immunoblastic lymphoma and multiple myeloma. Although one form of PTLD may progress to another form, only 1 previous case has been reported in which multiple myeloma developed 14 months after an original diagnosis of plasmacytic hyperplasia. The type of solid organ transplant was not specified in that case. We report a post--cardiac transplant plasmacytic hyperplasia developing 7 years posttransplant. Six years subsequent to the plasmacytic hyperplasia, the patient developed a posttransplant plasmacytic malignancy, supported by morphology, flow cytometric immunophenotyping, and genotypic studies. Since we have no data to support disseminated bony disease or an abnormal serum protein, we have not used the term "multiple myeloma" for this case.

On-chip activation and subsequent detection of individual antigen-specific T cells

PubMed Central

Song, Qing; Han, Qing; Bradshaw, Elizabeth M.; Kent, Sally C.; Raddassi, Khadir; Nilsson, Björn; Nepom, Gerald T.; Hafler, David A.; Love, J. Christopher

2010-01-01

The frequencies of antigen-specific CD4+ T cells in samples of human tissue has been difficult to determine accurately ex vivo, particularly for autoimmune diseases such as multiple sclerosis or Type 1 diabetes. Conventional approaches involve the expansion of primary T cells in vitro to increase the numbers of cells, and a subsequent assessment of the frequencies of antigen-specific T cells in the expanded population by limiting dilution or by using fluorescently labeled tetramers of peptide-loaded major histocompatibility complex (MHC) receptors. Here we describe an alternative approach that uses arrays of subnanoliter wells coated with recombinant peptide-loaded MHC Class II monomers to isolate and stimulate individual CD4+ T cells in an antigen-specific manner. In these experiments, activation was monitored using microengraving to capture two cytokines (IFNγ and IL-17) released from single cells. This new method should enable direct enumeration of antigen-specific CD4+ T cells ex vivo from clinical samples. PMID:20000848

[Effects of infrasound therapy on proliferation, apoptosis and ultrastructure of human B lymphoma Raji cells].

PubMed

Bao, Yong; Fan, Jian-Zhong; Li, Ke; Li, Chuan; Yang, Jun-Feng

2008-06-01

To investigate the effect of infrasound therapy on the proliferation, apoptosis and ultrastructure of human B lymphoma Raji cells. Human B lymphoma Raji cells were exposed to infrasound treatment for 15, 30, 60, 90 and 120 min and cultured subsequently for 24 or 48 h. MTT assay, flow cytometry analysis, and electron microscopy were performed to examine the proliferative status, cell apoptosis and ultrastructural changes of the exposed cells, respectively. MTT assay revealed no significant changes in the proliferation of the cells exposed to infrasound treatment (P>0.05), nor did flow cytometry analysis identified significant variation in the cell apoptosis (P>0.05). Scanning electron microscopy, however, identified shortened or reduced cell processes and microvilli on the surface of the cells with infrasound exposure and a subsequent 24-hour culture, and the cell membrane surface became smooth. Under transmission electron microscope, the cells with infrasound treatment presented with significantly reduced microvilli, and the cell nuclei appeared homogeneous, with cytoplasmic budding and losses after a 48-hour culture. Infrasound less than 90 dB does not obviously affect the proliferation and apoptosis of Raji cells, but may directly cause cell ultrastructural changes such as reduction of the cell processes.

Fabrication of uniform multi-compartment particles using microfludic electrospray technology for cell co-culture studies.

PubMed

Liu, Zhou; Shum, Ho Cheung

2013-01-01

In this work, we demonstrate a robust and reliable approach to fabricate multi-compartment particles for cell co-culture studies. By taking advantage of the laminar flow within our microfluidic nozzle, multiple parallel streams of liquids flow towards the nozzle without significant mixing. Afterwards, the multiple parallel streams merge into a single stream, which is sprayed into air, forming monodisperse droplets under an electric field with a high field strength. The resultant multi-compartment droplets are subsequently cross-linked in a calcium chloride solution to form calcium alginate micro-particles with multiple compartments. Each compartment of the particles can be used for encapsulating different types of cells or biological cell factors. These hydrogel particles with cross-linked alginate chains show similarity in the physical and mechanical environment as the extracellular matrix of biological cells. Thus, the multi-compartment particles provide a promising platform for cell studies and co-culture of different cells. In our study, cells are encapsulated in the multi-compartment particles and the viability of cells is quantified using a fluorescence microscope after the cells are stained for a live/dead assay. The high cell viability after encapsulation indicates the cytocompatibility and feasibility of our technique. Our multi-compartment particles have great potential as a platform for studying cell-cell interactions as well as interactions of cells with extracellular factors.

Fabrication of uniform multi-compartment particles using microfludic electrospray technology for cell co-culture studies

PubMed Central

Liu, Zhou; Shum, Ho Cheung

2013-01-01

In this work, we demonstrate a robust and reliable approach to fabricate multi-compartment particles for cell co-culture studies. By taking advantage of the laminar flow within our microfluidic nozzle, multiple parallel streams of liquids flow towards the nozzle without significant mixing. Afterwards, the multiple parallel streams merge into a single stream, which is sprayed into air, forming monodisperse droplets under an electric field with a high field strength. The resultant multi-compartment droplets are subsequently cross-linked in a calcium chloride solution to form calcium alginate micro-particles with multiple compartments. Each compartment of the particles can be used for encapsulating different types of cells or biological cell factors. These hydrogel particles with cross-linked alginate chains show similarity in the physical and mechanical environment as the extracellular matrix of biological cells. Thus, the multi-compartment particles provide a promising platform for cell studies and co-culture of different cells. In our study, cells are encapsulated in the multi-compartment particles and the viability of cells is quantified using a fluorescence microscope after the cells are stained for a live/dead assay. The high cell viability after encapsulation indicates the cytocompatibility and feasibility of our technique. Our multi-compartment particles have great potential as a platform for studying cell-cell interactions as well as interactions of cells with extracellular factors. PMID:24404050

The therapeutic response of CDDO-Me in the esophageal squamous cell carcinoma (ESCC) cells is mediated by CaMKIIα.

PubMed

Wang, Yan-Yang; Zhou, Shun; Zhao, Ren; Hai, Ping; Zhe, Hong

2016-01-01

CDDO-Me has exhibited a potent anticancer effect in human esophageal squamous cell carcinoma (ESCC) cells in our previous study, but the molecular interactome remains elusive. We applied the approach of stable-isotope labeling by amino acids in cell culture (SILAC) to assess the proteomic responses of CDDO-Me treatment in human ESCC Ec109 cells. The data were subsequently validated using Western blot assay. The results of our study revealed that CDDO-Me increased the expression level of 543 protein molecules, but decreased the expression level of 709 protein molecules in Ec109 cells. Among these modulated protein molecules, calcium/calmodulin-dependent protein kinase type II subunit α (CaMKIIα) was highly expressed in all tested ESCC cell lines, whereas its expression levels were substantially lower in normal control cell line. Its silencing by small interfering RNA inhibited CDDO-Me induced apoptosis and autophagy in ESCC cells. Collectively, these data demonstrate that the therapeutic response of CDDO-Me in the human ESCC cells is mediated by CaMKIIα.

Cytotoxic cells induced after Chlamydia psittaci infection in mice

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

Lammert, J.K.

1982-03-01

The ability of spleen cells from Chlamydia psittaci-infected mice to lyse C. psittaci-infected and uninfected target cell monolayers was studied. The cytotoxicity assay used was a terminal label method in which the number of adherent target cells surviving the interaction with effector cells was determined by measuring the uptake of (3H)uridine by such cells. It was observed that in the first few days postinfection (3 to 5), spleens contained cells that lysed infected and uninfected targets with equal efficiency. Subsequently, infected targets were killed primarily. The activity of effector spleen cells for infected targets continued, although at a reduced level,more » beyond 21 days postinfection. Intact effector cells were required since a disruption by sonication resulted in a loss of cytotoxicity. The enhanced killing observed with infected targets was also observed when target cells were sensitized with heat- or UV-inactivated C. psittaci. This study suggests that the induction of cytotoxic cells after C. psittaci infection may contribute to the ability of the host to control multiplication of the microorganism.« less

Development of a 3D co-culture model using human stem cells for studying embryonic palatal fusion.

EPA Science Inventory

Morphogenetic tissue fusion is a critical and complex event in embryonic development and failure of this event leads to birth defects, such as cleft palate. Palatal fusion requires adhesion and subsequent dissolution of the medial epithelial layer of the mesenchymal palatal shelv...

Neem Leaf Glycoprotein Prophylaxis Transduces Immune Dependent Stop Signal for Tumor Angiogenic Switch within Tumor Microenvironment

PubMed Central

Banerjee, Saptak; Ghosh, Tithi; Barik, Subhasis; Das, Arnab; Ghosh, Sarbari; Bhuniya, Avishek

2014-01-01

We have reported that prophylactic as well as therapeutic administration of neem leaf glycoprotein (NLGP) induces significant restriction of solid tumor growth in mice. Here, we investigate whether the effect of such pretreatment (25µg/mice; weekly, 4 times) benefits regulation of tumor angiogenesis, an obligate factor for tumor progression. We show that NLGP pretreatment results in vascular normalization in melanoma and carcinoma bearing mice along with downregulation of CD31, VEGF and VEGFR2. NLGP pretreatment facilitates profound infiltration of CD8+ T cells within tumor parenchyma, which subsequently regulates VEGF-VEGFR2 signaling in CD31+ vascular endothelial cells to prevent aberrant neovascularization. Pericyte stabilization, VEGF dependent inhibition of VEC proliferation and subsequent vascular normalization are also experienced. Studies in immune compromised mice confirmed that these vascular and intratumoral changes in angiogenic profile are dependent upon active adoptive immunity particularly those mediated by CD8+ T cells. Accumulated evidences suggest that NLGP regulated immunomodulation is active in tumor growth restriction and normalization of tumor angiogenesis as well, thereby, signifying its clinical translation. PMID:25391149

Neem leaf glycoprotein prophylaxis transduces immune dependent stop signal for tumor angiogenic switch within tumor microenvironment.

PubMed

Banerjee, Saptak; Ghosh, Tithi; Barik, Subhasis; Das, Arnab; Ghosh, Sarbari; Bhuniya, Avishek; Bose, Anamika; Baral, Rathindranath

2014-01-01

We have reported that prophylactic as well as therapeutic administration of neem leaf glycoprotein (NLGP) induces significant restriction of solid tumor growth in mice. Here, we investigate whether the effect of such pretreatment (25µg/mice; weekly, 4 times) benefits regulation of tumor angiogenesis, an obligate factor for tumor progression. We show that NLGP pretreatment results in vascular normalization in melanoma and carcinoma bearing mice along with downregulation of CD31, VEGF and VEGFR2. NLGP pretreatment facilitates profound infiltration of CD8+ T cells within tumor parenchyma, which subsequently regulates VEGF-VEGFR2 signaling in CD31+ vascular endothelial cells to prevent aberrant neovascularization. Pericyte stabilization, VEGF dependent inhibition of VEC proliferation and subsequent vascular normalization are also experienced. Studies in immune compromised mice confirmed that these vascular and intratumoral changes in angiogenic profile are dependent upon active adoptive immunity particularly those mediated by CD8+ T cells. Accumulated evidences suggest that NLGP regulated immunomodulation is active in tumor growth restriction and normalization of tumor angiogenesis as well, thereby, signifying its clinical translation.

Preparation of protein- and cell-resistant surfaces by hyperthermal hydrogen induced cross-linking of poly(ethylene oxide).

PubMed

Bonduelle, Colin V; Lau, Woon M; Gillies, Elizabeth R

2011-05-01

The functionalization of surfaces with poly(ethylene oxide) (PEO) is an effective means of imparting resistance to the adsorption of proteins and the attachment and growth of cells, properties that are critical for many biomedical applications. In this work, a new hyperthermal hydrogen induced cross-linking (HHIC) method was explored as a simple one-step approach for attaching PEO to surfaces through the selective cleavage of C-H bonds and subsequent cross-linking of the resulting carbon radicals. In order to study the effects of the process on the polymer, PEO-coated silicon wafers were prepared and the effects of different treatment times were investigated. Subsequently, using an optimized treatment time and a modified butyl polymer with increased affinity for PEO, the technique was applied to butyl rubber surfaces. All of the treated surfaces exhibited significantly reduced protein adsorption and cell growth relative to control surfaces and compared favorably with surfaces that were functionalized with PEO using conventional chemical methods. Thus HHIC is a simple and effective means of attaching PEO to non-functional polymer surfaces.

An investigation into the preservation of microbial cell banks for α-amylase production during 5 l fed-batch Bacillus licheniformis fermentations.

PubMed

Hancocks, Nichola H; Thomas, Colin R; Stocks, Stuart M; Hewitt, Christopher J

2010-10-01

Fluorescent staining techniques were used for a systematic examination of methods used to cryopreserve microbial cell banks. The aim of cryopreservation here is to ensure subsequent reproducible fermentation performance rather than just post thaw viability. Bacillus licheniformis cell physiology post-thaw is dependent on the cryopreservant (either Tween 80, glycerol or dimethyl sulphoxide) and whilst this had a profound effect on the length of the lag phase, during subsequent 5 l fed-batch fermentations, it had little effect on maximum specific growth rate, final biomass concentration or α-amylase activity. Tween 80 not only protected the cells during freezing but also helped them recover post-thaw resulting in shorter process times.

A novel microfluidic platform for size and deformability based separation and the subsequent molecular characterization of viable circulating tumor cells.

PubMed

Hvichia, G E; Parveen, Z; Wagner, C; Janning, M; Quidde, J; Stein, A; Müller, V; Loges, S; Neves, R P L; Stoecklein, N H; Wikman, H; Riethdorf, S; Pantel, K; Gorges, T M

2016-06-15

Circulating tumor cells (CTCs) were introduced as biomarkers more than 10 years ago, but capture of viable CTCs at high purity from peripheral blood of cancer patients is still a major technical challenge. Here, we report a novel microfluidic platform designed for marker independent capture of CTCs. The Parsortix™ cell separation system provides size and deformability-based enrichment with automated staining for cell identification, and subsequent recovery (harvesting) of cells from the device. Using the Parsortix™ system, average cell capture inside the device ranged between 42% and 70%. Subsequent harvest of cells from the device ranged between 54% and 69% of cells captured. Most importantly, 99% of the isolated tumor cells were viable after processing in spiking experiments as well as after harvesting from patient samples and still functional for downstream molecular analysis as demonstrated by mRNA characterization and array-based comparative genomic hybridization. Analyzing clinical blood samples from metastatic (n = 20) and nonmetastatic (n = 6) cancer patients in parallel with CellSearch(®) system, we found that there was no statistically significant difference between the quantitative behavior of the two systems in this set of twenty six paired separations. In conclusion, the epitope independent Parsortix™ system enables the isolation of viable CTCs at a very high purity. Using this system, viable tumor cells are easily accessible and ready for molecular and functional analysis. The system's ability for enumeration and molecular characterization of EpCAM-negative CTCs will help to broaden research into the mechanisms of cancer as well as facilitating the use of CTCs as "liquid biopsies." © 2016 The Authors International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.

A successful education program for parents of infants with newly diagnosed sickle cell disease.

PubMed

Day, S; Brunson, G; Wang, W

1992-02-01

The most dramatic recent advance in the care of young children with sickle cell disease was the demonstration by a cooperative study that the use of oral penicillin prophylaxis is highly effective in decreasing the risk of pneumococcal sepsis. Subsequently, the need for more comprehensive education of the parents of these children to ensure compliance with penicillin administration has become apparent. Over the past 4 years, the Mid-South Sickle Cell Disease Program has used a seven-phase educational process for the parents of more than 200 infants with newly diagnosed sickle cell disease. This has resulted in excellent compliance and a marked decrease in the incidence of pneumococcal sepsis among sickle cell patients at our center.

Antiangiogenic therapy improves the antitumor effect of adoptive cell immunotherapy by normalizing tumor vasculature.

PubMed

Shi, Shujing; Chen, Longbang; Huang, Guichun

2013-12-01

Abnormal tumor vasculature and subsequent tumor hypoxia contribute to immune tolerance of tumor cells by impeding the homing of cytotoxic T cells into tumor parenchyma and inhibiting their antitumor efficacy. These obstacles might explain why the promising approach of adoptive cell immunotherapy does not exert significant antitumor activity. Hypoxia contributes to immune suppression by activating hypoxia-inducible factor (HIF-1) and the vascular endothelial growth factor pathway, which plays a determining role in promoting tumor cell growth and survival. Tumor hypoxia creates an immunosuppressive microenvironment via the accumulation and subsequent polarization of inflammatory cells toward immune suppression phenotypes, such as myeloid-derived suppressor cells, tumor-associated macrophages, and dendritic cells. Antiangiogenic therapy could normalize tumor vasculature and decrease hypoxic tumor area and thus may be an effective modality to potentiate immunotherapy. Adoptive cell immunotherapy alone is not efficient enough to decrease tumor growth as its antitumor effect is inhibited by the immunosuppressive hypoxic tumor microenvironment. This review describes that combination of antiangiogenic therapy with adoptive cell immunotherapy can exert synergistic antitumor effect, which will contribute to improve strategies for future anticancer therapies.

Transport, manipulation, and reaction of biological cells on-chip using electrokinetic effects.

PubMed

Li, P C; Harrison, D J

1997-04-15

A microfluidic system was fabricated on a glass chip to study mobilization of biological cells on-chip. Electroosmotic and/or electrophoretic pumping were used to drive the cell transport within a network of capillary channels. Whole cells such as Saccharomyces cerevisiae, canine erythrocyte, and Escherichia coli were employed in this work. Photographs are presented to illustrate how cells are selected and transported from one location to another within the capillary network, with velocities up to about 0.5 mm/s in capillaries with a 15- x 55-microns cross section. The mixing of canine erythrocytes with the lysing agent sodium dodecyl sulfate, at an intersection within the chip, was performed to demonstrate that cell selection and subsequent reaction can be accomplished within the microchip.

Chitosan microsphere scaffold tethered with RGD-conjugated poly(methacrylic acid) brushes as effective carriers for the endothelial cells.

PubMed

Yang, Zhenyi; Yuan, Shaojun; Liang, Bin; Liu, Yang; Choong, Cleo; Pehkonen, Simo O

2014-09-01

Endothelial cell-matrix interactions play a vital role in promoting vascularization of engineered tissues. The current study reports a facile and controllable method to develop a RGD peptide-functionalized chitosan microsphere scaffolds for rapid cell expansion of human umbilical vein endothelial cells (HUVECs). Functional poly(methacrylic acid) (PMAA) brushes are grafted from the chitosan microsphere surfaces via surface-initiated ATRP. Subsequent conjugation of RGD peptides on the pendent carboxyl groups of PMAA side chain is accomplished by carbodiimide chemistry to facilitate biocompatibility of the 3D CS scaffolding system. In vitro cell-loading assay of HUVECs exhibits a significant improvment of cell adhesion, spreading, and proliferation on the RGD peptide-immobilized CS microsphere surfaces. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quantitative high-resolution genomic analysis of single cancer cells.

PubMed

Hannemann, Juliane; Meyer-Staeckling, Sönke; Kemming, Dirk; Alpers, Iris; Joosse, Simon A; Pospisil, Heike; Kurtz, Stefan; Görndt, Jennifer; Püschel, Klaus; Riethdorf, Sabine; Pantel, Klaus; Brandt, Burkhard

2011-01-01

During cancer progression, specific genomic aberrations arise that can determine the scope of the disease and can be used as predictive or prognostic markers. The detection of specific gene amplifications or deletions in single blood-borne or disseminated tumour cells that may give rise to the development of metastases is of great clinical interest but technically challenging. In this study, we present a method for quantitative high-resolution genomic analysis of single cells. Cells were isolated under permanent microscopic control followed by high-fidelity whole genome amplification and subsequent analyses by fine tiling array-CGH and qPCR. The assay was applied to single breast cancer cells to analyze the chromosomal region centred by the therapeutical relevant EGFR gene. This method allows precise quantitative analysis of copy number variations in single cell diagnostics.

Transcellular transport of cobalamin in aortic endothelial cells.

PubMed

Hannibal, Luciana; Bolisetty, Keerthana; Axhemi, Armend; DiBello, Patricia M; Quadros, Edward V; Fedosov, Sergey; Jacobsen, Donald W

2018-05-09

Cobalamin [Cbl (or B 12 )] deficiency causes megaloblastic anemia and a variety of neuropathies. However, homeostatic mechanisms of cyanocobalamin (CNCbl) and other Cbls by vascular endothelial cells are poorly understood. Herein, we describe our investigation into whether cultured bovine aortic endothelial cells (BAECs) perform transcytosis of B 12 , namely, the complex formed between serum transcobalamin and B 12 , designated as holo-transcobalamin (holo-TC). We show that cultured BAECs endocytose [ 57 Co]-CNCbl-TC (source material) via the CD320 receptor. The bound Cbl is transported across the cell both via exocytosis in its free form, [ 57 Co]-CNCbl, and via transcytosis as [ 57 Co]-CNCbl-TC. Transcellular mobilization of Cbl occurred in a bidirectional manner. A portion of the endocytosed [ 57 Co]-CNCbl was enzymatically processed by methylmalonic aciduria combined with homocystinuria type C (cblC) with subsequent formation of hydroxocobalamin, methylcobalamin, and adenosylcobalamin, which were also transported across the cell in a bidirectional manner. This demonstrates that transport mechanisms for Cbl in vascular endothelial cells do not discriminate between various β-axial ligands of the vitamin. Competition studies with apoprotein- and holo-TC and holo-intrinsic factor showed that only holo-TC was effective at inhibiting transcellular transport of Cbl. Incubation of BAECs with a blocking antibody against the extracellular domain of the CD320 receptor inhibited uptake and transcytosis by ∼40%. This study reveals that endothelial cells recycle uncommitted intracellular Cbl for downstream usage by other cell types and suggests that the endothelium is self-sufficient for the specific acquisition and subsequent distribution of circulating B 12 via the CD320 receptor. We posit that the endothelial lining of the vasculature is an essential component for the maintenance of serum-tissue homeostasis of B 12 .-Hannibal, L., Bolisetty, K., Axhemi, A., DiBello, P. M., Quadros, E. V., Fedosov, S., Jacobsen, D. W. Transcellular transport of cobalamin in aortic endothelial cells.

Programmed death-1 controls T cell survival by regulating oxidative metabolism1

PubMed Central

Tkachev, Victor; Goodell, Stefanie; Opipari, Anthony W.; Hao, Ling-Yang; Franchi, Luigi; Glick, Gary D.; Ferrara, James L.M.; Byersdorfer, Craig A.

2015-01-01

The co-inhibitory receptor programmed death-1 (PD-1) maintains immune homeostasis by negatively regulating T cell function and survival. Blockade of PD-1 increases the severity of graft-versus-host disease (GVHD), but the interplay between PD-1 inhibition and T cell metabolism is not well studied. We found that both murine and human alloreactive T cells concomitantly up-regulated PD-1 expression and increased levels of reactive oxygen species (ROS) following allogeneic bone marrow transplantation. This PD-1HiROSHi phenotype was specific to alloreactive T cells and was not observed in syngeneic T cells during homeostatic proliferation. Blockade of PD-1 signaling decreased both mitochondrial H2O2 and total cellular ROS levels and PD-1 driven increases in ROS were dependent upon the oxidation of fatty acids, as treatment with etomoxir nullified changes in ROS levels following PD-1 blockade. Downstream of PD-1, elevated ROS levels impaired T cell survival in a process reversed by anti-oxidants. Furthermore, PD-1 driven changes in ROS were fundamental to establishing a cell’s susceptibility to subsequent metabolic inhibition, as blockade of PD-1 decreased the efficacy of later F1F0-ATP synthase modulation. These data indicate that PD-1 facilitates apoptosis in alloreactive T cells by increasing reactive oxygen species in a process dependent upon the oxidation of fat. In addition, blockade of PD-1 undermines the potential for subsequent metabolic inhibition, an important consideration given the increasing use of anti-PD-1 therapies in the clinic. PMID:25972478

Magnetically levitated mesenchymal stem cell spheroids cultured with a collagen gel maintain phenotype and quiescence

PubMed Central

Lewis, Natasha S; Lewis, Emily EL; Mullin, Margaret; Wheadon, Helen; Dalby, Matthew J; Berry, Catherine C

2017-01-01

Multicellular spheroids are an established system for three-dimensional cell culture. Spheroids are typically generated using hanging drop or non-adherent culture; however, an emerging technique is to use magnetic levitation. Herein, mesenchymal stem cell spheroids were generated using magnetic nanoparticles and subsequently cultured within a type I collagen gel, with a view towards developing a bone marrow niche environment. Cells were loaded with magnetic nanoparticles, and suspended beneath an external magnet, inducing self-assembly of multicellular spheroids. Cells in spheroids were viable and compared to corresponding monolayer controls, maintained stem cell phenotype and were quiescent. Interestingly, core spheroid necrosis was not observed, even with increasing spheroid size, in contrast to other commonly used spheroid systems. This mesenchymal stem cell spheroid culture presents a potential platform for modelling in vitro bone marrow stem cell niches, elucidating interactions between cells, as well as a useful model for drug delivery studies. PMID:28616152

Thermo-electrochemical instrumentation of cylindrical Li-ion cells

NASA Astrophysics Data System (ADS)

McTurk, Euan; Amietszajew, Tazdin; Fleming, Joe; Bhagat, Rohit

2018-03-01

The performance evaluation and optimisation of commercially available lithium-ion cells is typically based upon their full cell potential and surface temperature measurements, despite these parameters not being fully representative of the electrochemical processes taking place in the core of the cell or at each electrode. Several methods were devised to obtain the cell core temperature and electrode-specific potential profiles of cylindrical Li-ion cells. Optical fibres with Bragg Gratings were found to produce reliable core temperature data, while their small mechanical profile allowed for low-impact instrumentation method. A pure metallic lithium reference electrode insertion method was identified, avoiding interference with other elements of the cell while ensuring good contact, enabling in-situ observations of the per-electrode electrochemical responses. Our thermo-electrochemical instrumentation technique has enabled us to collect unprecedented cell data, and has subsequently been used in advanced studies exploring the real-world performance limits of commercial cells.

Cell wall elasticity: I. A critique of the bulk elastic modulus approach and an analysis using polymer elastic principles

NASA Technical Reports Server (NTRS)

Wu, H. I.; Spence, R. D.; Sharpe, P. J.; Goeschl, J. D.

1985-01-01

The traditional bulk elastic modulus approach to plant cell pressure-volume relations is inconsistent with its definition. The relationship between the bulk modulus and Young's modulus that forms the basis of their usual application to cell pressure-volume properties is demonstrated to be physically meaningless. The bulk modulus describes stress/strain relations of solid, homogeneous bodies undergoing small deformations, whereas the plant cell is best described as a thin-shelled, fluid-filled structure with a polymer base. Because cell walls possess a polymer structure, an alternative method of mechanical analysis is presented using polymer elasticity principles. This initial study presents the groundwork of polymer mechanics as would be applied to cell walls and discusses how the matrix and microfibrillar network induce nonlinear stress/strain relationships in the cell wall in response to turgor pressure. In subsequent studies, these concepts will be expanded to include anisotropic expansion as regulated by the microfibrillar network.

NHS-based Tandem Mass Tagging of Proteins at the Level of Whole Cells: A Critical Evaluation in Comparison to Conventional TMT-Labeling Approaches for Quantitative Proteome Analysis.

PubMed

Megger, Dominik A; Pott, Leona L; Rosowski, Kristin; Zülch, Birgit; Tautges, Stephanie; Bracht, Thilo; Sitek, Barbara

2017-01-01

Tandem mass tags (TMT) are usually introduced at the levels of isolated proteins or peptides. Here, for the first time, we report the labeling of whole cells and a critical evaluation of its performance in comparison to conventional labeling approaches. The obtained results indicated that TMT protein labeling using intact cells is generally possible, if it is coupled to a subsequent enrichment using anti-TMT antibody. The quantitative results were similar to those obtained after labeling of isolated proteins and both were found to be slightly complementary to peptide labeling. Furthermore, when using NHS-based TMT, no specificity towards cell surface proteins was observed in the case of cell labeling. In summary, the conducted study revealed first evidence for the general possibility of TMT cell labeling and highlighted limitations of NHS-based labeling reagents. Future studies should therefore focus on the synthesis and investigation of membrane impermeable TMTs to increase specificity towards cell surface proteins.

Neuroprotective and antioxidant activities of bamboo salt soy sauce against H2O2-induced oxidative stress in rat cortical neurons.

PubMed

Jeong, Jong Hee; Noh, Min-Young; Choi, Jae-Hyeok; Lee, Haiwon; Kim, Seung Hyun

2016-04-01

Bamboo salt (BS) and soy sauce (SS) are traditional foods in Asia, which contain antioxidants that have cytoprotective effects on the body. The majority of SS products contain high levels of common salt, consumption of which has been associated with numerous detrimental effects on the body. However, BS may be considered a healthier substitute to common salt. The present study hypothesized that SS made from BS, known as bamboo salt soy sauce (BSSS), may possess enhanced cytoprotective properties; this was evaluated using a hydrogen peroxide (H 2 O 2 )-induced neuronal cell death rat model. Rat neuronal cells were pretreated with various concentrations (0.001, 0.01, 0.1, 1 and 10%) of BSSS, traditional soy sauce (TRSS) and brewed soy sauce (BRSS), and were subsequently exposed to H 2 O 2 (100 µM). The viability of neuronal cells, and the occurrence of DNA fragmentation, was subsequently examined. Pretreatment of neuronal cells with TRSS and BRSS reduced cell viability in a concentration-dependent manner, whereas neuronal cells pretreated with BSSS exhibited increased cell viability, as compared with non-treated neuronal cells. Furthermore, neuronal cells pretreated with 0.01% BSSS exhibited the greatest increase in viability. Exposure of neuronal cells to H 2 O 2 significantly increased the levels of reactive oxygen species (ROS), B-cell lymphoma 2-associated X protein, poly (ADP-ribose), cleaved poly (ADP-ribose) polymerase, cytochrome c , apoptosis-inducing factor, cleaved caspase-9 and cleaved caspase-3, in all cases. Pretreatment of neuronal cells with BSSS significantly reduced the levels of ROS generated by H 2 O 2 , and increased the levels of phosphorylated AKT and phosphorylated glycogen synthase kinase-3β. Furthermore, the observed effects of BSSS could be blocked by administration of 10 µM LY294002, a phosphatidylinositol 3-kinase inhibitor. The results of the present study suggested that BSSS may exert positive neuroprotective effects against H 2 O 2 -induced cell death by reducing oxidative stress, enhancing survival signaling, and inhibiting death signals.

Cytomorphology of Circulating Colorectal Tumor Cells:A Small Case Series

PubMed Central

Marrinucci, Dena; Bethel, Kelly; Lazar, Daniel; Fisher, Jennifer; Huynh, Edward; Clark, Peter; Bruce, Richard; Nieva, Jorge; Kuhn, Peter

2010-01-01

Several methodologies exist to enumerate circulating tumor cells (CTCs) from the blood of cancer patients; however, most methodologies lack high-resolution imaging, and thus, little is known about the cytomorphologic features of these cells. In this study of metastatic colorectal cancer patients, we used immunofluorescent staining with fiber-optic array scanning technology to identify CTCs, with subsequent Wright-Giemsa and Papanicolau staining. The CTCs were compared to the corresponding primary and metastatic tumors. The colorectal CTCs showed marked intrapatient pleomorphism. In comparison to the corresponding tissue biopsies, cells from all sites showed similar pleomorphism, demonstrating that colorectal CTCs retain the pleomorphism present in regions of solid growth. They also often retain particular cytomorphologic features present in the patient's primary and/or metastatic tumor tissue. This study provides an initial analysis of the cytomorphologic features of circulating colon cancer cells, providing a foundation for further investigation into the significance and metastatic potential of CTCs. PMID:20111743

Feasibility study of a mini fuel cell to detect interference from a cellular phone

NASA Astrophysics Data System (ADS)

Abdullah, M. O.; Gan, Y. K.

Fuel cells produce electricity without involving combustion processes. They generate no noise, vibration or air pollution and are therefore suitable for use in many vibration-free power-generating applications. In this study, a mini alkaline fuel cell signal detector system has been designed, constructed and tested. The initial results have shown the applicability of such system for used as an indicator of signal disturbance from cellular phones. A small disturbance even at 4 mV cm -1, corresponding to an amplitude of 12-18 mG in terms of electromagnetic field, can be well detected by such a device. Subsequently, a thermodynamics model has been developed to provide a parametric study by simulation to show the likely performance of the fuel cell alone in other environments. As such the model can provide many useful generic design data for alkaline fuel cells. Two general conclusions can be drawn from the present theoretical study: (i) fuel cell performance increases with temperature, pressure and correction factor, C f; (ii) the temperature factor (E/ T) increases with increasing temperature and with increasing pressure factor.

Cell proliferation inhibition in reduced gravity

NASA Technical Reports Server (NTRS)

Moos, P. J.; Fattaey, H. K.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

1994-01-01

Extended durations of spaceflight have been shown to be deleterious on an organismic level; however, mechanisms underlying cellular sensitivity to the gravitational environment remain to be elucidated. The majority of the gravitational studies to date indicates that cell regulatory pathways may be influenced by their gravitational environment. Still, few cell biology experiments have been performed in space flight and even fewer experiments have been repeated on subsequent flights. With flight opportunities on STS-50, 54, and 57, Sf9 cells were flown in the BioServe Fluids Processing Apparatus and cell proliferation was measured with and without exposure to a cell regulatory sialoglycopeptide (CeReS) inhibitor. Results from these flights indicate that the Sf9 cells grew comparable to ground controls, that the CeReS inhibitor bound to its specific receptor, and that its signal transduction cascade was not gravity sensitive.

Vasopressin stimulates DNA synthesis and ion transport in quiescent epithelial cells.

PubMed

Reznik, V M; Shapiro, R J; Mendoza, S A

1985-09-01

The mitogenic effect of vasopressin was studied in subconfluent quiescent renal epithelial cells (MDCK). Vasopressin stimulated DNA synthesis in the presence of low concentrations of serum. Vasopressin increased the entry of Na into the cells and increased ouabain-sensitive 86Rb uptake, a measure of Na-K pump activity. Because the activity of the Na-K pump in MDCK cells is steeply dependent on intracellular Na, it is likely that stimulation of the Na-K pump by vasopressin was mediated by the increase in Na entry into the cells. Thus both serum and vasopressin stimulate Na uptake and Na-K pump activity in quiescent MDCK cells with a subsequent increase in DNA synthesis. It is concluded that growth regulation in epithelial cells may be mediated in part by changes in monovalent ion transport.

A high dose of intravenous immunoglobulin increases CD94 expression on natural killer cells in women with recurrent spontaneous abortion.

PubMed

Shimada, Shigeki; Takeda, Masamitsu; Nishihira, Jun; Kaneuchi, Masanori; Sakuragi, Noriaki; Minakami, Hisanori; Yamada, Hideto

2009-11-01

A high dose of intravenous immunoglobulin (HIVIg) therapy is effective in various diseases such as autoimmune diseases, and also is expected to have efficacy in recurrent spontaneous abortion (RSA). The aim of this study was to understand immunological mechanisms of this therapy. By flowcytometric analyses, we examined phenotypic changes of a variety of immunological cells including natural killer (NK) cells, cytotoxic T cells, regulatory T cells and macrophages in peripheral blood of RSA women with HIVIg therapy (n = 8). Expression percentages of inhibitory CD94 on NK cells significantly (P = 0.01) increased after the therapy (58.8 +/- 21.4% versus 71.0 +/- 17.6%). Mechanisms of possible efficacy of HIVIg therapy for RSA may include enhancement of CD94 expression and subsequent suppression of NK cell cytotoxicity.

Stem cell plasticity enables hair regeneration following Lgr5+ cell loss.

PubMed

Hoeck, Joerg D; Biehs, Brian; Kurtova, Antonina V; Kljavin, Noelyn M; de Sousa E Melo, Felipe; Alicke, Bruno; Koeppen, Hartmut; Modrusan, Zora; Piskol, Robert; de Sauvage, Frederic J

2017-06-01

Under injury conditions, dedicated stem cell populations govern tissue regeneration. However, the molecular mechanisms that induce stem cell regeneration and enable plasticity are poorly understood. Here, we investigate stem cell recovery in the context of the hair follicle to understand how two molecularly distinct stem cell populations are integrated. Utilizing diphtheria-toxin-mediated cell ablation of Lgr5 + (leucine-rich repeat-containing G-protein-coupled receptor 5) stem cells, we show that killing of Lgr5 + cells in mice abrogates hair regeneration but this is reversible. During recovery, CD34 + (CD34 antigen) stem cells activate inflammatory response programs and start dividing. Pharmacological attenuation of inflammation inhibits CD34 + cell proliferation. Subsequently, the Wnt pathway controls the recovery of Lgr5 + cells and inhibition of Wnt signalling prevents Lgr5 + cell and hair germ recovery. Thus, our study uncovers a compensatory relationship between two stem cell populations and the underlying molecular mechanisms that enable hair follicle regeneration.

On the origin of biological construction, with a focus on multicellularity.

PubMed

van Gestel, Jordi; Tarnita, Corina E

2017-10-17

Biology is marked by a hierarchical organization: all life consists of cells; in some cases, these cells assemble into groups, such as endosymbionts or multicellular organisms; in turn, multicellular organisms sometimes assemble into yet other groups, such as primate societies or ant colonies. The construction of new organizational layers results from hierarchical evolutionary transitions, in which biological units (e.g., cells) form groups that evolve into new units of biological organization (e.g., multicellular organisms). Despite considerable advances, there is no bottom-up, dynamical account of how, starting from the solitary ancestor, the first groups originate and subsequently evolve the organizing principles that qualify them as new units. Guided by six central questions, we propose an integrative bottom-up approach for studying the dynamics underlying hierarchical evolutionary transitions, which builds on and synthesizes existing knowledge. This approach highlights the crucial role of the ecology and development of the solitary ancestor in the emergence and subsequent evolution of groups, and it stresses the paramount importance of the life cycle: only by evaluating groups in the context of their life cycle can we unravel the evolutionary trajectory of hierarchical transitions. These insights also provide a starting point for understanding the types of subsequent organizational complexity. The central research questions outlined here naturally link existing research programs on biological construction (e.g., on cooperation, multilevel selection, self-organization, and development) and thereby help integrate knowledge stemming from diverse fields of biology.

Fate of nuclear material during subsequent steps of the kinetin-induced PCD in apical parts of Vicia faba ssp. minor seedling roots.

PubMed

Kaźmierczak, Andrzej; Soboska, Kamila

2018-07-01

In animals during apoptosis, the best examined type of programmed cell death (PCD), three main phases are distinguished: (i) specification (signaling), (ii) killing and (iii) execution one. It has bean postulated that plant PCD also involves three subsequent phases: (i) transmission of death signals to cells (signaling), (ii) initiation of killing processes and (iii) destruction of cells. One of the most important hallmarks of animal and plant PCD are those regarding nucleus, not thoroughly studied in plants so far. To study kinetin-induced PCD (Kin-PCD) in the context of nuclear material faith, 2-cm apical parts of Vicia faba ssp. minor seedling roots were used. Applied assays involving spectrophotometry, transmission electron microscopy, fluorescence and white light microscopy allowed to examine metabolic and cytomorphologic hallmarks such as changes in DNA content, ssDNA formation and activity of acidic and basic nucleases (DNases and RNases) as well as malformations and fragmentation of nucleoli and nuclei. The obtained results concerning the PCD hallmarks and influence of ZnSO 4 on Kin-PCD allowed us to confirmed presence of specification/signaling, killing and execution/degradation phases of the process and broaden the knowledge about processes affecting nuclei during PCD. Copyright © 2018 Elsevier Ltd. All rights reserved.

Basolateral cholesterol depletion alters Aquaporin-2 post-translational modifications and disrupts apical plasma membrane targeting.

PubMed

Moeller, Hanne B; Fuglsang, Cecilia Hvitfeldt; Pedersen, Cecilie Nøhr; Fenton, Robert A

2018-01-01

Apical plasma membrane accumulation of the water channel Aquaporin-2 (AQP2) in kidney collecting duct principal cells is critical for body water homeostasis. Posttranslational modification (PTM) of AQP2 is important for regulating AQP2 trafficking. The aim of this study was to determine the role of cholesterol in regulation of AQP2 PTM and in apical plasma membrane targeting of AQP2. Cholesterol depletion from the basolateral plasma membrane of a collecting duct cell line (mpkCCD14) using methyl-beta-cyclodextrin (MBCD) increased AQP2 ubiquitylation. Forskolin, cAMP or dDAVP-mediated AQP2 phosphorylation at Ser269 (pS269-AQP2) was prevented by cholesterol depletion from the basolateral membrane. None of these effects on pS269-AQP2 were observed when cholesterol was depleted from the apical side of cells, or when MBCD was applied subsequent to dDAVP stimulation. Basolateral, but not apical, MBCD application prevented cAMP-induced apical plasma membrane accumulation of AQP2. These studies indicate that manipulation of the cholesterol content of the basolateral plasma membrane interferes with AQP2 PTM and subsequently regulated apical plasma membrane targeting of AQP2. Copyright © 2017 Elsevier Inc. All rights reserved.

Macrophages clear refrigerator storage-damaged RBCs and subsequently secrete cytokines in vivo, but not in vitro, in a murine model

PubMed Central

Wojczyk, Boguslaw S.; Kim, Nina; Bandyopadhyay, Sheila; Francis, Richard O.; Zimring, James C.; Hod, Eldad A.; Spitalnik, Steven L.

2014-01-01

BACKGROUND In mice, refrigerator-stored red blood cells (RBCs) are cleared by extravascular hemolysis and induce cytokine production. To enhance understanding of this phenomenon, we sought to model it in vitro. STUDY DESIGN AND METHODS Ingestion of refrigerator-stored murine RBCs and subsequent cytokine production were studied using J774A.1 mouse macrophage cells and primary murine splenic macrophages. Wild-type and Ccl2-GFP-reporter mice were used for RBC clearance in vivo. RESULTS Although J774A.1 cells and primary macrophages preferentially ingested refrigerator-stored RBCs in vitro, as compared to freshly-isolated RBCs, neither produced increased cytokines following erythrophagocytosis. In contrast, phagocytosis of refrigerator-stored RBCs in vivo induced increases in circulating monocyte chemoattractant protein-1 (MCP-1) and keratinocyte chemoattractant (KC), and correspondingly increased mRNA levels in mouse spleen and liver. In the spleen, these were predominantly expressed by CD11b+ cells. Using Ccl2-GFP-reporter mice, the predominant splenic population responsible for MCP-1 mRNA production were tissue-resident macrophages (i.e., CD45+, CD11b+, F4/80+, Ly6c+, CD11clow cells). CONCLUSION J774A.1 cells and primary macrophages selectively ingested refrigerator-stored RBCs by phagocytosis. Although cytokine expression was not enhanced, this approach could be used to identify the relevant receptor-ligand combination(s). In contrast, cytokine levels increased following phagocytosis of refrigerator-stored RBCs in vivo. These were primarily cleared in the liver and spleen, which demonstrated increased MCP-1 and KC mRNA expression. Finally, in mouse spleen, tissue-resident macrophages were predominantly involved in MCP-1 mRNA production. The differences between cytokine production in vitro and in vivo are not yet well understood. PMID:25041478

Bexarotene via CBP/p300 induces suppression of NF-κB-dependent cell growth and invasion in thyroid cancer.

PubMed

Cras, Audrey; Politis, Béatrice; Balitrand, Nicole; Darsin-Bettinger, Diane; Boelle, Pierre Yves; Cassinat, Bruno; Toubert, Marie-Elisabeth; Chomienne, Christine

2012-01-15

Retinoic acid (RA) treatment has been used for redifferentiation of metastatic thyroid cancer with loss of radioiodine uptake. The aim of this study was to improve the understanding of RA resistance and investigate the role of bexarotene in thyroid cancer cells. A model of thyroid cancer cell lines with differential response to RA was used to evaluate the biological effects of retinoid and rexinoid and to correlate this with RA receptor levels. Subsequently, thyroid cancer patients were treated with 13-cis RA and bexarotene and response evaluated on radioiodine uptake reinduction on posttherapy scan and conventional imaging. In thyroid cancer patients, 13-cis RA resistance can be bypassed in some tumors by bexarotene. A decreased tumor growth without differentiation was observed confirming our in vitro data. Indeed, we show that ligands of RARs or RXRs exert different effects in thyroid cancer cell lines through either differentiation or inhibition of cell growth and invasion. These effects are associated with restoration of RARβ and RXRγ levels and downregulation of NF-κB targets genes. We show that bexarotene inhibits the transactivation potential of NF-κB in an RXR-dependent manner through decreased promoter permissiveness without interfering with NF-κB nuclear translocation and binding to its responsive elements. Inhibition of transcription results from the release of p300 coactivator from NF-κB target gene promoters and subsequent histone deacetylation. This study highlights dual mechanisms by which retinoids and rexinoids may target cell tumorigenicity, not only via RARs and RXRs, as expected, but also via NF-κB pathway. ©2011 AACR.

Apoptosis-mediated seasonal testicular regression in the Japanese Jungle Crow (Corvus macrorhynchos).

PubMed

Islam, M Nazrul; Tsukahara, N; Sugita, S

2012-06-01

The present study investigated effects of apoptosis observed during seasonal testicular regression in Japanese Jungle Crows. The study was conducted during January to June 2008, 2009. Testes from adults captured during non-breeding (January), prebreeding (February to mid-March), main-breeding (late March to early May), transition (mid-May to late May), and post-breeding (June) seasons were analyzed. Apoptosis was assessed by in situ terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. Paired-testis volume increased 95-fold from the non-breeding to the main-breeding season (P < 0.05), and subsequently decreased 26-fold from the main breeding to the post-breeding season (P < 0.05). Testicular activity was evaluated from the total germ cell count and sperm index, which increased 42- and 5-fold, respectively, in the main-breeding season, and subsequently decreased 33- and 5-fold in the post-breeding season. In testes, TUNEL-positive germ cells were at low levels in the non-breeding season, absent in the prebreeding and the main-breeding seasons, and highest in mid-May (P < 0.05). In contrast, TUNEL-positive Sertoli cells occurred only in late-April. In addition, TUNEL-positive fibroblast-like cells were observed in the outer zone of the tunica albuginea in the post-breeding season. Collectively, these data suggested that the seasonal rise in the testicular competence occurred slowly in Japanese Jungle Crows; however, testis function was terminated rapidly after the breeding season. Furthermore, we concluded, similar to other avian species, Sertoli cell apoptosis followed by massive germ cell death was responsible for rapid testicular regression in Jungle Crows. Copyright © 2012 Elsevier Inc. All rights reserved.

Autocrine inhibition of the c-fms proto-oncogene reduces breast cancer bone metastasis assessed with in vivo dual-modality imaging.

PubMed

Jeffery, Justin J; Lux, Katie; Vogel, John S; Herrera, Wynetta D; Greco, Stephen; Woo, Ho-Hyung; AbuShahin, Nisreen; Pagel, Mark D; Chambers, Setsuko K

2014-04-01

Breast cancer cells preferentially home to the bone microenvironment, which provides a unique niche with a network of multiple bidirectional communications between host and tumor, promoting survival and growth of bone metastases. In the bone microenvironment, the c-fms proto-oncogene that encodes for the CSF-1 receptor, along with CSF-1, serves as one critical cytokine/receptor pair, functioning in paracrine and autocrine fashion. Previous studies concentrated on the effect of inhibition of host (mouse) c-fms on bone metastasis, with resulting decrease in osteolysis and bone metastases as a paracrine effect. In this report, we assessed the role of c-fms inhibition within the tumor cells (autocrine effect) in the early establishment of breast cancer cells in bone and the effects of this early c-fms inhibition on subsequent bone metastases and destruction. This study exploited a multidisciplinary approach by employing two non-invasive, in vivo imaging methods to assess the progression of bone metastases and bone destruction, in addition to ex vivo analyses using RT-PCR and histopathology. Using a mouse model of bone homing human breast cancer cells, we showed that an early one-time application of anti-human c-fms antibody delayed growth of bone metastases and bone destruction for at least 31 days as quantitatively measured by bioluminescence imaging and computed tomography, compared to controls. Thus, neutralizing human c-fms in the breast cancer cell alone decreases extent of subsequent bone metastasis formation and osteolysis. Furthermore, we are the first to show that anti-c-fms antibodies can impact early establishment of breast cancer cells in bone.

Mitosis can drive cell cannibalism through entosis

PubMed Central

Durgan, Joanne; Tseng, Yun-Yu; Hamann, Jens C; Domart, Marie-Charlotte; Collinson, Lucy; Overholtzer, Michael; Florey, Oliver

2017-01-01

Entosis is a form of epithelial cell cannibalism that is prevalent in human cancer, typically triggered by loss of matrix adhesion. Here, we report an alternative mechanism for entosis in human epithelial cells, driven by mitosis. Mitotic entosis is regulated by Cdc42, which controls mitotic morphology. Cdc42 depletion enhances mitotic deadhesion and rounding, and these biophysical changes, which depend on RhoA activation and are phenocopied by Rap1 inhibition, permit subsequent entosis. Mitotic entosis occurs constitutively in some human cancer cell lines and mitotic index correlates with cell cannibalism in primary human breast tumours. Adherent, wild-type cells can act efficiently as entotic hosts, suggesting that normal epithelia may engulf and kill aberrantly dividing neighbours. Finally, we report that Paclitaxel/taxol promotes mitotic rounding and subsequent entosis, revealing an unconventional activity of this drug. Together, our data uncover an intriguing link between cell division and cannibalism, of significance to both cancer and chemotherapy. DOI: http://dx.doi.org/10.7554/eLife.27134.001 PMID:28693721

Synthesis of EF24-tripeptide chloromethyl ketone: a novel curcumin-related anticancer drug delivery system.

PubMed

Sun, Aiming; Shoji, Mamoru; Lu, Yang J; Liotta, Dennis C; Snyder, James P

2006-06-01

The blood coagulation cascade includes a step in which the soluble protein, factor VIIa (fVIIa), complexes with its transmembrane receptor, tissue factor (TF). The fVIIa/TF protein-protein complex is subsequently drawn into the cell by endocytosis. The observation that TF is aberrantly and abundantly expressed on many cancer cells offers an opportunity to specifically target those cells with an effective anticancer drug. Thus, we propose a new drug delivery system, drug-linker-Phe-Phe-Arg-mk-fVIIa, which can associate with TF on the surface of cancer cells, but release the cytotoxic agent in the cytoplasm. Synthetic procedures have been developed for the preparation of phenylalanine-phenylalanine-arginine chloromethyl ketone, (FFRck) followed by coupling with the cytotoxin EF24 and subsequently fVIIa to give EF-24-FFRmk-fVIIa. When breast cancer cells (MDA-MB-231) and human melanoma cells (RPMI-7951) are treated with the complex, the cells are arrested to a greater extent than EF24 alone by comparison with controls.

SEWAGE OFF-GAS-DRIVEN FUEL CELLS TO STIMULATE RURAL ELECTRIFICATION

EPA Science Inventory

Literature reviews confirmed the feasibility of the system relying on methane to supply the fuel cell and the waste heat from the subsequent fuel cell operation driving the decomposition process. A batch bioreactor and a proton exchange fuel cell at the lab scale are used to c...

Method of fabricating a monolithic solid oxide fuel cell

DOEpatents

Minh, N.Q.; Horne, C.R.

1994-03-01

In a two-step densifying process of making a monolithic solid oxide fuel cell, a limited number of anode-electrolyte-cathode cells separated by an interconnect layer are formed and partially densified. Subsequently, the partially densified cells are stacked and further densified to form a monolithic array. 10 figures.

Method of fabricating a monolithic solid oxide fuel cell

DOEpatents

Minh, Nguyen Q.; Horne, Craig R.

1994-01-01

In a two-step densifying process of making a monolithic solid oxide fuel cell, a limited number of anode-electrolyte-cathode cells separated by an interconnect layer are formed and partially densified. Subsequently, the partially densified cells are stacked and further densified to form a monolithic array.

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

Nielsen, Nathalie; Laustsen, Christoffer; Bertelsen, Lotte Bonde, E-mail: Lotte@clin.au.dk

Endothelial progenitor cells (EPCs) represent a heterogeneous cell population that is believed to be involved in vasculogenesis. With the purpose of enhancing endothelial repair, EPCs could have a potential for future cell therapies. Due to the low amount of EPCs in the peripheral circulating blood, in vitro expansion is needed before administration to recipients and the effects of in vitro culturing is still an under-evaluated field with little knowledge of how the cells change over time in culture. The aim of this study was to use hyperpolarised carbon-13 magnetic resonance spectroscopy to profile important metabolic pathways in a population ofmore » progenitor cells and to show that cell culturing in 3D scaffolds seem to block the metabolic processes that leads to cell senescence. The metabolic breakdown of hyperpolarized [1-{sup 13}C]pyruvate was followed after injection of the substrate to a bioreactor system with EPCs either adhered to 3D printed scaffolds or kept in cell suspension. The pyruvate-to-lactate conversion was elevated in suspension of EPCs compared to the EPCs adhered to scaffolds. Furthermore in the setup with EPCs in suspension, an increase in lactate production was seen over time indicating that the older the cultures of EPCs was before using the cells for cell suspension experiments, the more lactate they produce, compared to a constant lactate level in the cells adhered to scaffolds. It could therefore be stated that cells grown first in 2D culture and subsequent prepared for cell suspension show a metabolism with higher lactate production consistent with cells senescence processes compared to cells grown first at 2D culture and subsequent in the 3D printed scaffolds, where metabolism shows no sign of metabolic shifting during the monitored period. - Highlights: • Hyperpolarized 13C MRS detects EPCs metabolic changes associated with ageing and cultivating conditions. • Increased lactate production in EPC’s correlates positively with aging. • 2D cultivation show an increased lactate production, while 3D cultivation show a maintained lactate production.« less

MPLEx: a method for simultaneous pathogen inactivation and extraction of samples for multi-omics profiling.

PubMed

Burnum-Johnson, Kristin E; Kyle, Jennifer E; Eisfeld, Amie J; Casey, Cameron P; Stratton, Kelly G; Gonzalez, Juan F; Habyarimana, Fabien; Negretti, Nicholas M; Sims, Amy C; Chauhan, Sadhana; Thackray, Larissa B; Halfmann, Peter J; Walters, Kevin B; Kim, Young-Mo; Zink, Erika M; Nicora, Carrie D; Weitz, Karl K; Webb-Robertson, Bobbie-Jo M; Nakayasu, Ernesto S; Ahmer, Brian; Konkel, Michael E; Motin, Vladimir; Baric, Ralph S; Diamond, Michael S; Kawaoka, Yoshihiro; Waters, Katrina M; Smith, Richard D; Metz, Thomas O

2017-01-26

The continued emergence and spread of infectious agents is of great concern, and systems biology approaches to infectious disease research can advance our understanding of host-pathogen relationships and facilitate the development of new therapies and vaccines. Molecular characterization of infectious samples outside of appropriate biosafety containment can take place only subsequent to pathogen inactivation. Herein, we describe a modified Folch extraction using chloroform/methanol that facilitates the molecular characterization of infectious samples by enabling simultaneous pathogen inactivation and extraction of proteins, metabolites, and lipids for subsequent mass spectrometry-based multi-omics measurements. This single-sample metabolite, protein and lipid extraction (MPLEx) method resulted in complete inactivation of clinically important bacterial and viral pathogens with exposed lipid membranes, including Yersinia pestis, Salmonella Typhimurium, and Campylobacter jejuni in pure culture, and Yersinia pestis, Campylobacter jejuni, and West Nile, MERS-CoV, Ebola, and influenza H7N9 viruses in infection studies. In addition, >99% inactivation, which increased with solvent exposure time, was also observed for pathogens without exposed lipid membranes including community-associated methicillin-resistant Staphylococcus aureus, Clostridium difficile spores and vegetative cells, and adenovirus type 5. The overall pipeline of inactivation and subsequent proteomic, metabolomic, and lipidomic analyses was evaluated using a human epithelial lung cell line infected with wild-type and mutant influenza H7N9 viruses, thereby demonstrating that MPLEx yields biomaterial of sufficient quality for subsequent multi-omics analyses. Based on these experimental results, we believe that MPLEx will facilitate systems biology studies of infectious samples by enabling simultaneous pathogen inactivation and multi-omics measurements from a single specimen with high success for pathogens with exposed lipid membranes.

MPLEx: A method for simultaneous pathogen inactivation and extraction of samples for multi-omics profiling

PubMed Central

Burnum-Johnson, Kristin E.; Kyle, Jennifer E.; Eisfeld, Amie J.; Casey, Cameron P.; Stratton, Kelly G.; Gonzalez, Juan F.; Habyarimana, Fabien; Negretti, Nicholas M.; Sims, Amy C.; Chauhan, Sadhana; Thackray, Larissa B.; Halfmann, Peter J.; Walters, Kevin B.; Kim, Young-Mo; Zink, Erika M.; Nicora, Carrie D.; Weitz, Karl K.; Webb-Robertson, Bobbie-Jo M.; Nakayasu, Ernesto S.; Ahmer, Brian; Konkel, Michael E.; Motin, Vladimir; Baric, Ralph S.; Diamond, Michael S.; Kawaoka, Yoshihiro; Waters, Katrina M.; Smith, Richard D.; Metz, Thomas O.

2017-01-01

The continued emergence and spread of infectious agents is of great concern, and systems biology approaches to infectious disease research can advance our understanding of host-pathogen relationships and facilitate the development of new therapies and vaccines. Molecular characterization of infectious samples outside of appropriate biosafety containment can take place only subsequent to pathogen inactivation. Herein, we describe a modified Folch extraction using chloroform/methanol that facilitates the molecular characterization of infectious samples by enabling simultaneous pathogen inactivation and extraction of proteins, metabolites, and lipids for subsequent mass spectrometry-based multi-omics measurements. This single-sample metabolite, protein and lipid extraction (MPLEx) method resulted in complete inactivation of clinically important bacterial and viral pathogens with exposed lipid membranes, including Yersinia pestis, Salmonella Typhimurium, and Campylobacter jejuni in pure culture, and Yersinia pestis, Campylobacter jejuni, and West Nile, MERS-CoV, Ebola, and influenza H7N9 viruses in infection studies. In addition, >99% inactivation, which increased with solvent exposure time, was also observed for pathogens without exposed lipid membranes including community-associated methicillin-resistant Staphylococcus aureus, Clostridium difficile spores and vegetative cells, and adenovirus type 5. The overall pipeline of inactivation and subsequent proteomic, metabolomic, and lipidomic analyses was evaluated using a human epithelial lung cell line infected with wild-type and mutant influenza H7N9 viruses, thereby demonstrating that MPLEx yields biomaterial of sufficient quality for subsequent multi-omics analyses. Based on these experimental results, we believe that MPLEx will facilitate systems biology studies of infectious samples by enabling simultaneous pathogen inactivation and multi-omics measurements from a single specimen with high success for pathogens with exposed lipid membranes. PMID:28091625

Thiol trapping and metabolic redistribution of sulfur metabolites enable cells to overcome cysteine overload

PubMed Central

Deshpande, Anup Arunrao; Bhatia, Muskan; Laxman, Sunil; Bachhawat, Anand Kumar

2017-01-01

Cysteine is an essential requirement in living organisms. However, due to its reactive thiol side chain, elevated levels of intracellular cysteine can be toxic and therefore need to be rapidly eliminated from the cellular milieu. In mammals and many other organisms, excess cysteine is believed to be primarily eliminated by the cysteine dioxygenase dependent oxidative degradation of cysteine, followed by the removal of the oxidative products. However, other mechanisms of tackling excess cysteine are also likely to exist, but have not thus far been explored. In this study, we use Saccharomyces cerevisiae, which naturally lacks a cysteine dioxygenase, to investigate mechanisms for tackling cysteine overload. Overexpressing the high affinity cysteine transporter, YCT1, enabled yeast cells to rapidly accumulate high levels of intracellular cysteine. Using targeted metabolite analysis, we observe that cysteine is initially rapidly interconverted to non-reactive cystine in vivo. A time course revealed that cells systematically convert excess cysteine to inert thiol forms; initially to cystine, and subsequently to cystathionine, S-Adenosyl-L-homocysteine (SAH) and S-Adenosyl L-methionine (SAM), in addition to eventually accumulating glutathione (GSH) and polyamines. Microarray based gene expression studies revealed the upregulation of arginine/ornithine biosynthesis a few hours after the cysteine overload, and suggest that the non-toxic, non-reactive thiol based metabolic products are eventually utilized for amino acid and polyamine biogenesis, thereby enabling cell growth. Thus, cells can handle potentially toxic amounts of cysteine by a combination of thiol trapping, metabolic redistribution to non-reactive thiols and subsequent consumption for anabolism. PMID:28435838

Umbilical cord tissue-derived mesenchymal stromal cells maintain immunomodulatory and angiogenic potencies after cryopreservation and subsequent thawing.

PubMed

Bárcia, Rita N; Santos, Jorge M; Teixeira, Mariana; Filipe, Mariana; Pereira, Ana Rita S; Ministro, Augusto; Água-Doce, Ana; Carvalheiro, Manuela; Gaspar, Maria Manuela; Miranda, Joana P; Graça, Luis; Simões, Sandra; Santos, Susana Constantino Rosa; Cruz, Pedro; Cruz, Helder

2017-03-01

The effect of cryopreservation on mesenchymal stromal cell (MSC) therapeutic properties has become highly controversial. However, data thus far have indiscriminately involved the assessment of different types of MSCs with distinct production processes. This study assumed that MSC-based products are affected differently depending on the tissue source and manufacturing process and analyzed the effect of cryopreservation on a specific population of umbilical cord tissue-derived MSCs (UC-MSCs), UCX ® . Cell phenotype was assessed by flow cytometry through the evaluation of the expression of relevant surface markers such as CD14, CD19, CD31, CD34, CD44, CD45, CD90, CD105, CD146, CD200, CD273, CD274 and HLA-DR. Immunomodulatory activity was analyzed in vitro through the ability to inhibit activated T cells and in vivo by the ability to reverse the signs of inflammation in an adjuvant-induced arthritis (AIA) model. Angiogenic potential was evaluated in vitro using a human umbilical vein endothelial cell-based angiogenesis assay, and in vivo using a mouse model for hindlimb ischemia. Phenotype and immunomodulatory and angiogenic potencies of this specific UC-MSC population were not impaired by cryopreservation and subsequent thawing, both in vitro and in vivo. This study suggests that potency impairment related to cryopreservation in a given tissue source can be avoided by the production process. The results have positive implications for the development of advanced-therapy medicinal products. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Biological Behavior of Osteoblast Cell and Apatite Forming Ability of the Surface Modified Ti Alloys.

PubMed

Zhao, Jingming; Hwang, K H; Choi, W S; Shin, S J; Lee, J K

2016-02-01

Titanium as one kind of biomaterials comes in direct contact with the body, making evaluation of biocompatibility an important aspect to biomaterials development. Surface chemistry of titanium plays an important role in osseointegration. Different surface modification alters the surface chemistry and result in different biological response. In this study, three kinds of mixed acid solutions were used to treat Ti specimens to induce Ca-P formation. Following a strong mixed acid activation process, Ca-P coating successfully formed on the Ti surfaces in simulated body fluid. Strong mixed acid increased the roughness of the metal surface, because the porous and rough surface allows better adhesion between Ca-P coatings and substrates. After modification of titanium surface by mixed acidic solution and subsequently H2O2/HCL treatment evaluation of biocompatibility was conducted from hydroxyapatite formation by biomimetic process and cell viability on modified titanium surface. Nano-scale modification of titanium surfaces can alter cellular and tissue responses, which may benefit osseointegration and dental implant therapy. Results from this study indicated that surface treatment methods affect the surface morphology, type of TiO2 layer formed and subsequent apatite deposition and biological responses. The thermo scientific alamarblue cell viability assay reagent is used to quantitatively measure the viability of mammalian cell lines, bacteria and fungi by incorporating a rapid, sensitive and reliable fluorometric/colorimetric growth indicator, without any toxic and side effect to cell line. In addition, mixed acid treatment uses a lower temperature and shorter time period than widely used alkali treatment.

Protein profiling of single epidermal cell types from Arabidopsis thaliana using surface-enhanced laser desorption and ionization technology.

PubMed

Ebert, Berit; Melle, Christian; Lieckfeldt, Elke; Zöller, Daniela; von Eggeling, Ferdinand; Fisahn, Joachim

2008-08-25

Here, we describe a novel approach for investigating differential protein expression within three epidermal cell types. In particular, 3000 single pavement, basal, and trichome cells from leaves of Arabidopsis thaliana were harvested by glass micro-capillaries. Subsequently, these single cell samples were joined to form pools of 100 individual cells and analyzed using the ProteinChip technology; SELDI: surface-enhanced laser desorption and ionization. As a result, numerous protein signals that were differentially expressed in the three epidermal cell types could be detected. One of these proteins was characterized by tryptical digestion and subsequent identification via tandem quadrupole-time of flight (Q-TOF) mass spectrometry. Down regulation of this sequenced small subunit precursor of ribulose-1,5 bisphosphate carboxylase(C) oxygenase(O) (RuBisCo) in trichome and basal cells indicates the sink status of these cell types that are located on the surface of A. thaliana source leaves. Based on the obtained protein profiles, we suggest a close functional relationship between basal and trichome cells at the protein level.

Red sorrel (Hibiscus Sabdariffa) prevents the ethanol-induced deficits of Purkinje cells in the cerebellum.

PubMed

Suryanti, S; Partadiredja, G; Atthobari, J

2015-01-01

The present study is aimed at investigating the possible protective effects of H. sabdariffa on ethanol-elicited deficits of motor coordination and estimated total number of the Purkinje cells of the cerebellums of adolescent male Wistar rats. Forty male Wistar rats aged 21 days were divided into five groups. Na/wtr group was given water orally and injected with normal saline intra peritoneally (ip). Eth/wtr group was given water orally and ethanol (ip). Another three experimental groups (Eth/Hsab) were given different dosages of H. sabdariffa and ethanol (ip). All groups were treated intermittently for the total period of treatment of two weeks. The motor coordination of rats was tested prior and subsequent to the treatments. The rats were euthanized, and their cerebellums were examined. The total number of Purkinje cells was estimated using physical fractionator method. Upon revolving drum test, the number of falls of rats increased following ethanol treatment. There was no significant difference between the total number of falls prior and subsequent to treatment in all Eth/Hsab groups. The estimated total number of Purkinje cells in Eth/Hsab groups was higher than in Eth/wtr group. H. sabdariffa may prevent the ethanol-induced deficits of motor coordination and estimated total number of Purkinje cells of the cerebellums in adolescent rats (Tab. 3, Fig. 1, Ref. 42).

Cell Density Affects the Detection of Chk1 Target Engagement by the Selective Inhibitor V158411.

PubMed

Geneste, Clara C; Massey, Andrew J

2018-02-01

Understanding drug target engagement and the relationship to downstream pharmacology is critical for drug discovery. Here we have evaluated target engagement of Chk1 by the small-molecule inhibitor V158411 using two different target engagement methods (autophosphorylation and cellular thermal shift assay [CETSA]). Target engagement measured by these methods was subsequently related to Chk1 inhibitor-dependent pharmacology. Inhibition of autophosphorylation was a robust method for measuring V158411 Chk1 target engagement. In comparison, while target engagement determined using CETSA appeared robust, the V158411 CETSA target engagement EC 50 values were 43- and 19-fold greater than the autophosphorylation IC 50 values. This difference was attributed to the higher cell density in the CETSA assay configuration. pChk1 (S296) IC 50 values determined using the CETSA assay conditions were 54- and 33-fold greater than those determined under standard conditions and were equivalent to the CETSA EC 50 values. Cellular conditions, especially cell density, influenced the target engagement of V158411 for Chk1. The effects of high cell density on apparent compound target engagement potency should be evaluated when using target engagement assays that necessitate high cell densities (such as the CETSA conditions used in this study). In such cases, the subsequent relation of these data to downstream pharmacological changes should therefore be interpreted with care.

Skin Dendritic Cell Targeting via Microneedle Arrays Laden with Antigen-Encapsulated Poly-d,l-lactide-co-Glycolide Nanoparticles Induces Efficient Antitumor and Antiviral Immune Responses

PubMed Central

2013-01-01

The efficacious delivery of antigens to antigen-presenting cells (APCs), in particular, to dendritic cells (DCs), and their subsequent activation remains a significant challenge in the development of effective vaccines. This study highlights the potential of dissolving microneedle (MN) arrays laden with nanoencapsulated antigen to increase vaccine immunogenicity by targeting antigen specifically to contiguous DC networks within the skin. Following in situ uptake, skin-resident DCs were able to deliver antigen-encapsulated poly-d,l-lactide-co-glycolide (PGLA) nanoparticles to cutaneous draining lymph nodes where they subsequently induced significant expansion of antigen-specific T cells. Moreover, we show that antigen-encapsulated nanoparticle vaccination via microneedles generated robust antigen-specific cellular immune responses in mice. This approach provided complete protection in vivo against both the development of antigen-expressing B16 melanoma tumors and a murine model of para-influenza, through the activation of antigen-specific cytotoxic CD8+ T cells that resulted in efficient clearance of tumors and virus, respectively. In addition, we show promising findings that nanoencapsulation facilitates antigen retention into skin layers and provides antigen stability in microneedles. Therefore, the use of biodegradable polymeric nanoparticles for selective targeting of antigen to skin DC subsets through dissolvable MNs provides a promising technology for improved vaccination efficacy, compliance, and coverage. PMID:23373658

Aggregate formation affects ultrasonic disruption of microalgal cells.

PubMed

Wang, Wei; Lee, Duu-Jong; Lai, Juin-Yih

2015-12-01

Ultrasonication is a cell disruption process of low energy efficiency. This study dosed K(+), Ca(2+) and Al(3+) to Chlorella vulgaris cultured in Bold's Basal Medium at 25°C and measured the degree of cell disruption under ultrasonication. Adding these metal ions yielded less negatively charged surfaces of cells, while with the latter two ions large and compact cell aggregates were formed. The degree of cell disruption followed: control=K(+)>Ca(2+)>Al(3+) samples. Surface charges of cells and microbubbles have minimal effects on the microbubble number in the proximity of the microalgal cells. Conversely, cell aggregates with large size and compact interior resist cell disruption under ultrasonication. Staining tests revealed high diffusional resistance of stains over the aggregate interior. Microbubbles may not be effective generated and collapsed inside the compact aggregates, hence leading to low cell disruption efficiencies. Effective coagulation/flocculation in cell harvesting may lead to adverse effect on subsequent cell disruption efficiency. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effects of sodium hypochlorite and chlorhexidine irrigants on the antibacterial activities of alkaline media against Enterococcus faecalis.

PubMed

Ma, Jinglei; Tong, Zhongchun; Ling, Junqi; Liu, Hongyan; Wei, Xi

2015-07-01

Sodium hypochlorite (NaOCl), chlorhexidine (CHX) and calcium hydroxide are common intracanal medicaments. The present study aimed to evaluate the effects of NaOCl and CHX on the antibacterial activities of alkaline media against Enterococcus faecalis. The survival rates of planktonic and biofilm E. faecalis were evaluated by plate counts after 1 min of pretreatment with NaOCl and CHX, and time-kill assays were then used to assess subsequent pH alkaline challenges. Dead and living cells in the E. faecalis biofilm were assessed with SYTO 9 and PI staining in combination with confocal laser scanning microscopy following exposure to NaOCl or CHX and subsequent alkaline challenges by common root canal irrigation and dressing procedures. One minute of pretreatment with 2% CHX, 0.2% CHX, or 5.25% NaOCl in combination with a subsequent alkaline challenge significantly decreased planktonic E. faecalis survival rates, but pretreatment with 1% NaOCl did not. The E. faecalis biofilm survival rates were reduced in the subsequent alkaline challenge following CHX pretreatment but gradually increased following NaOCl pretreatment. Similarly, CLSM analysis revealed that the greatest proportions of dead E. faecalis cells in the biofilms were presented in the CHX and alkaline treatment group. CHX might be more effective in improving the antibacterial activities of alkaline root canal medicaments against E. faecalis than NaOCl during routine root canal therapy procedures. Copyright © 2015 Elsevier Ltd. All rights reserved.

Magneto-optical labeling of fetal neural stem cells for in vivo MRI tracking.

PubMed

Flexman, J A; Minoshima, S; Kim, Y; Cross, D J

2006-01-01

Neural stem cell therapy for neurological pathologies, such as Alzheimer's and Parkinson's disease, may delay the onset of symptoms, replace damaged neurons and/or support the survival of endogenous cells. Magnetic resonance imaging (MRI) can be used to track magnetically labeled cells in vivo to observe migration. Prior to transplantation, labeled cells must be characterized to show that they retain their intrinsic properties, such as cell proliferation into neurospheres in a supplemented environment. In vivo images must also be correlated to sensitive, histological markers. In this study, we show that fetus-derived neural stem cells can be co-labeled with superparamagnetic iron oxide and PKH26, a fluorescent dye. Labeled cells retain the ability to proliferate into neurospheres in culture, but labeling prevents neurospheres from merging in a non-adherent culture environment. After labeled NSCs were transplantation into the rat brain, their location and subsequent migration along the corpus callosum was detected using MRI. This study demonstrates an imaging paradigm with which to develop an in vivo assay for quantitatively evaluating fetal neural stem cell migration.

Cell-Free Translation of Integral Membrane Proteins into Unilamelar Liposomes

PubMed Central

Goren, Michael A.; Nozawa, Akira; Makino, Shin-ichi; Wrobel, Russell L.; Fox, Brian G.

2018-01-01

Wheat germ cell-free translation is shown to be an effective method to produce integral membrane proteins in the presence of unilamelar liposomes. In this chapter, we describe the expression vectors, preparation of mRNA, two types of cell-free translation reactions performed in the presence of liposomes, a simple and highly efficient purification of intact proteoliposomes using density gradient ultracentrifugation, and some of the types of characterization studies that are facilitated by this facile preparative approach. The in vitro transfer of newly translated, membrane proteins into liposomes compatible with direct measurements of their catalytic function is contrasted with existing approaches to extract membrane proteins from biological membranes using detergents and subsequently transfer them back to liposomes for functional studies. PMID:19892197

Phorbol esters alter adenylate cyclase responses to vasoactive intestinal peptide and forskolin in the GH cell line

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

Summers, S.; Florio, T.; Cronin, M.

1986-05-01

Activation of protein kinase C with phorbol ester modifies cyclic AMP production in several anterior pituitary cell systems. In the GH cell line from a rat pituitary tumor, exposure to phorbol 12-myristate 13-acetate (PMA: 100 nM) for 30 minutes significantly reduces vasoactive intestinal peptide (VIP: 100 nM) stimulated adenylate cyclase (AC) activity in subsequent membrane preparations to 62 + 4% of control (n = 6 independent studies). In contrast, these same membrane preparations respond to forskolin (1 ..mu..M) with significantly more activity, 130 +/- 6% of controls (n = 6 independent studies). Finally, phorbol ester does not block an inhibitorymore » hormone input into the AC system; somatostatin (100 nM) reduction of VIP-stimulated AC activity is not significantly different in membrane preparations from PMA treated and control cells (n = 3 independent studies). These other findings lead the authors to propose that protein kinase C can modify several sites in the AC complex in anterior pituitary cells.« less

Tracking dipeptides at work-uptake and intracellular fate in CHO culture.

PubMed

Sánchez-Kopper, Andres; Becker, Max; Pfizenmaier, Jennifer; Kessler, Christian; Karau, Andreas; Takors, Ralf

2016-12-01

Market demands for monoclonal antibodies (mAbs) are steadily increasing worldwide. As a result, production processes using Chinese hamster ovary cells (CHO) are in the focus of ongoing intensification studies for maximizing cell-specific and volumetric productivities. This includes the optimization of animal-derived component free (ADCF) cultivation media as part of good cell culture practice. Dipeptides are known to improve CHO culture performance. However, little or even conflicting assumptions exist about their putative import and functionality inside the cells. A set of well-known performance boosters and new dipeptide prospects was evaluated. The present study revealed that dipeptides are indeed imported in the cells, where they are decomposed to the amino acids building blocks. Subsequently, they are metabolized or, unexpectedly, secreted to the medium. Monoclonal antibody production boosting additives like L-alanine-L-glutamine (AQ) or glycyl-L-glutamine (GQ) can be assigned to fast or slow dipeptide uptake, respectively, thus pinpointing to the need to study dipeptide kinetics and to adjust their feeding individually for optimizing mAb production.

Cancer treatment in childhood and testicular function: the importance of the somatic environment.

PubMed

Stukenborg, Jan-Bernd; Jahnukainen, Kirsi; Hutka, Marsida; Mitchell, Rod T

2018-02-01

Testicular function and future fertility may be affected by cancer treatment during childhood. Whilst survival of the germ (stem) cells is critical for ensuring the potential for fertility in these patients, the somatic cell populations also play a crucial role in providing a suitable environment to support germ cell maintenance and subsequent development. Regulation of the spermatogonial germ-stem cell niche involves many signalling pathways with hormonal influence from the hypothalamo-pituitary-gonadal axis. In this review, we describe the somatic cell populations that comprise the testicular germ-stem cell niche in humans and how they may be affected by cancer treatment during childhood. We also discuss the experimental models that may be utilized to manipulate the somatic environment and report the results of studies that investigate the potential role of somatic cells in the protection of the germ cells in the testis from cancer treatment. © 2018 The authors.

Everolimus affects vasculogenic mimicry in renal carcinoma resistant to sunitinib

PubMed Central

Serova, Maria; Tijeras-Raballand, Annemilaï; Santos, Celia Dos; Martinet, Matthieu; Neuzillet, Cindy; Lopez, Alfred; Mitchell, Dianne C.; Bryan, Brad A.; Gapihan, Guillaume; Janin, Anne; Bousquet, Guilhem; Riveiro, Maria Eugenia; Bieche, Ivan; Faivre, Sandrine

2016-01-01

Angiogenesis is hallmark of clear cell renal cell carcinogenesis. Anti-angiogenic therapies have been successful in improving disease outcome; however, most patients treated with anti-angiogenic agents will eventually progress. In this study we report that clear cell renal cell carcinoma was associated with vasculogenic mimicry in both mice and human with tumor cells expressing endothelial markers in the vicinity of tumor vessels. We show that vasculogenic mimicry was efficiently targeted by sunitinib but eventually associated with tumor resistance and a more aggressive phenotype both in vitro and in vivo. Re-challenging these resistant tumors in mice, we showed that second-line treatment with everolimus particularly affected vasculogenic mimicry and tumor cell differentiation compared to sorafenib and axitinib. Finally, our results highlighted the phenotypic and genotypic changes at the tumor cell and microenvironment levels during sunitinib response and progression and the subsequent improvement second-line therapies bring to the current renal cell carcinoma treatment paradigm. PMID:27509260

Cancer treatment in childhood and testicular function: the importance of the somatic environment

PubMed Central

Stukenborg, Jan-Bernd; Jahnukainen, Kirsi; Hutka, Marsida

2018-01-01

Testicular function and future fertility may be affected by cancer treatment during childhood. Whilst survival of the germ (stem) cells is critical for ensuring the potential for fertility in these patients, the somatic cell populations also play a crucial role in providing a suitable environment to support germ cell maintenance and subsequent development. Regulation of the spermatogonial germ-stem cell niche involves many signalling pathways with hormonal influence from the hypothalamo-pituitary-gonadal axis. In this review, we describe the somatic cell populations that comprise the testicular germ-stem cell niche in humans and how they may be affected by cancer treatment during childhood. We also discuss the experimental models that may be utilized to manipulate the somatic environment and report the results of studies that investigate the potential role of somatic cells in the protection of the germ cells in the testis from cancer treatment. PMID:29351905

Granulocyte-macrophage colony stimulating factor (GM-CSF) enhances cumulus cell expansion in bovine oocytes

PubMed Central

2013-01-01

Background The objectives of the study were to characterize the expression of the α- and β-subunits of granulocyte-macrophage colony stimulating factor (GM-CSF) receptor in bovine cumulus cells and oocytes and to determine the effect of exogenous GM-CSF on cumulus cells expansion, oocyte maturation, IGF-2 transcript expression and subsequent competence for embryonic development. Methods Cumulus-oocyte complexes (COC) were obtained by aspirating follicles 3- to 8-mm in diameter with an 18 G needle connected to a vacuum pump at −50 mmHg. Samples of cumulus cells and oocytes were used to detect GM- CSF receptor by immunofluorescence. A dose–response experiment was performed to estimate the effect of GM-CSF on cumulus cell expansion and nuclear/cytoplasmic maturation. Also, the effect of GM-CSF on IGF-2 expression was evaluated in oocytes and cumulus cells after in vitro maturation by Q-PCR. Finally, a batch of COC was randomly assigned to in vitro maturation media consisting of: 1) synthetic oviductal fluid (SOF, n = 212); 2) synthetic oviductal fluid supplemented with 100 ng/ml of GM-CSF (SOF + GM-CSF, n = 224) or 3) tissue culture medium (TCM 199, n = 216) and then subsequently in vitro fertilized and cultured for 9 days. Results Immunoreactivity for both α and β GM-CSF receptors was localized in the cytoplasm of both cumulus cells and oocytes. Oocytes in vitro matured either with 10 or 100 ng/ml of GM-CSF presented a higher (P < 0.05) cumulus cells expansion than that of the control group (0 ng/ml of GM-CSF). GM-CSF did not affect the proportion of oocytes in metaphase II, cortical granules dispersion and IGF-2 expression. COC exposed to 100 ng/ml of GM-CSF during maturation did not display significant differences in terms of embryo cleavage rate (50.4% vs. 57.5%), blastocyst development at day 7 (31.9% vs. 28.7%) and at day 9 (17.4% vs. 17.9%) compared to untreated control (SOF alone, P = 0.2). Conclusions GM-CSF enhanced cumulus cell expansion of in vitro matured bovine COC. However, GM-CSF did not increase oocyte nuclear or cytoplasmic maturation rates, IGF-2 expression or subsequent embryonic development. PMID:23799974

Optimal conditions for peripheral nerve storage in green tea polyphenol: an experimental study in animals.

PubMed

Matsumoto, Taiichi; Kakinoki, Ryosuke; Ikeguchi, Ryosuke; Hyon, Suong-Hyu; Nakamura, Takashi

2005-06-30

Our previous study demonstrated successful peripheral nerve storage for 1 month using polyphenol solution. We here report two studies to solve residual problems in using polyphenols as a storage solution for peripheral nerves. Study 1 was designed to determine the optimal concentration of the polyphenol solution and the optimal immersion period for nerve storage. Rat sciatic nerve segments were immersed in polyphenol solution at three different concentrations (2.5, 1.0, and 0.5 mg/ml) for three different periods (1, 7, and 26 days). Electrophysiological and morphological studies demonstrated that nerve regeneration from nerve segments that had been immersed in 1mg/ml polyphenol solution for 1 week and in Dulbecco's modified Eagle's medium (DMEM) for the subsequent 3 weeks was superior to the regeneration in other treatment groups. In study 2, the permeability of nerve tissue to polyphenol solution was investigated using canine sciatic nerve segments stored in 1.0mg/ml polyphenol solution for 1 week and in DMEM for the subsequent 3 weeks. Electron microscopy revealed that the Schwann cell structure within 500-700 microm of the perineurium was preserved, but cells deeper than 500-700 microm were badly damaged or had disappeared. The infiltration limit for polyphenol solution into neural tissue is inferred to be 500-700 microm.

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.

Merck Ad5/HIV induces broad innate immune activation that predicts CD8⁺ T-cell responses but is attenuated by preexisting Ad5 immunity.

PubMed

Zak, Daniel E; Andersen-Nissen, Erica; Peterson, Eric R; Sato, Alicia; Hamilton, M Kristina; Borgerding, Joleen; Krishnamurty, Akshay T; Chang, Joanne T; Adams, Devin J; Hensley, Tiffany R; Salter, Alexander I; Morgan, Cecilia A; Duerr, Ann C; De Rosa, Stephen C; Aderem, Alan; McElrath, M Juliana

2012-12-11

To better understand how innate immune responses to vaccination can lead to lasting protective immunity, we used a systems approach to define immune signatures in humans over 1 wk following MRKAd5/HIV vaccination that predicted subsequent HIV-specific T-cell responses. Within 24 h, striking increases in peripheral blood mononuclear cell gene expression associated with inflammation, IFN response, and myeloid cell trafficking occurred, and lymphocyte-specific transcripts decreased. These alterations were corroborated by marked serum inflammatory cytokine elevations and egress of circulating lymphocytes. Responses of vaccinees with preexisting adenovirus serotype 5 (Ad5) neutralizing antibodies were strongly attenuated, suggesting that enhanced HIV acquisition in Ad5-seropositive subgroups in the Step Study may relate to the lack of appropriate innate activation rather than to increased systemic immune activation. Importantly, patterns of chemoattractant cytokine responses at 24 h and alterations in 209 peripheral blood mononuclear cell transcripts at 72 h were predictive of subsequent induction and magnitude of HIV-specific CD8(+) T-cell responses. This systems approach provides a framework to compare innate responses induced by vectors, as shown here by contrasting the more rapid, robust response to MRKAd5/HIV with that to yellow fever vaccine. When applied iteratively, the findings may permit selection of HIV vaccine candidates eliciting innate immune response profiles more likely to drive HIV protective immunity.

The Skeletal Muscle Satellite Cell

PubMed Central

2011-01-01

The skeletal muscle satellite cell was first described and named based on its anatomic location between the myofiber plasma and basement membranes. In 1961, two independent studies by Alexander Mauro and Bernard Katz provided the first electron microscopic descriptions of satellite cells in frog and rat muscles. These cells were soon detected in other vertebrates and acquired candidacy as the source of myogenic cells needed for myofiber growth and repair throughout life. Cultures of isolated myofibers and, subsequently, transplantation of single myofibers demonstrated that satellite cells were myogenic progenitors. More recently, satellite cells were redefined as myogenic stem cells given their ability to self-renew in addition to producing differentiated progeny. Identification of distinctively expressed molecular markers, in particular Pax7, has facilitated detection of satellite cells using light microscopy. Notwithstanding the remarkable progress made since the discovery of satellite cells, researchers have looked for alternative cells with myogenic capacity that can potentially be used for whole body cell-based therapy of skeletal muscle. Yet, new studies show that inducible ablation of satellite cells in adult muscle impairs myofiber regeneration. Thus, on the 50th anniversary since its discovery, the satellite cell’s indispensable role in muscle repair has been reaffirmed. PMID:22147605

Transient gibberellin application promotes Arabidopsis thaliana hypocotyl cell elongation without maintaining transverse orientation of microtubules on the outer tangential wall of epidermal cells.

PubMed

Sauret-Güeto, Susanna; Calder, Grant; Harberd, Nicholas P

2012-02-01

The phytohormone gibberellin (GA) promotes plant growth by stimulating cellular expansion. Whilst it is known that GA acts by opposing the growth-repressing effects of DELLA proteins, it is not known how these events promote cellular expansion. Here we present a time-lapse analysis of the effects of a single pulse of GA on the growth of Arabidopsis hypocotyls. Our analyses permit kinetic resolution of the transient growth effects of GA on expanding cells. We show that pulsed application of GA to the relatively slowly growing cells of the unexpanded light-grown Arabidopsis hypocotyl results in a transient burst of anisotropic cellular growth. This burst, and the subsequent restoration of initial cellular elongation rates, occurred respectively following the degradation and subsequent reappearance of a GFP-tagged DELLA (GFP-RGA). In addition, we used a GFP-tagged α-tubulin 6 (GFP-TUA6) to visualise the behaviour of microtubules (MTs) on the outer tangential wall (OTW) of epidermal cells. In contrast to some current hypotheses concerning the effect of GA on MTs, we show that the GA-induced boost of hypocotyl cell elongation rate is not dependent upon the maintenance of transverse orientation of the OTW MTs. This confirms that transverse alignment of outer face MTs is not necessary to maintain rapid elongation rates of light-grown hypocotyls. Together with future studies on MT dynamics in other faces of epidermal cells and in cells deeper within the hypocotyl, our observations advance understanding of the mechanisms by which GA promotes plant cell and organ growth. © 2011 The Authors. The Plant Journal © 2011 Blackwell Publishing Ltd.

Critical requirement for the Wiskott-Aldrich syndrome protein in Th2 effector function

USDA-ARS?s Scientific Manuscript database

The Wiskott-Aldrich syndrome protein (WASp) regulates actin polymerization via activation of Arp2/3 and plays a role in the dynamics of the immunological synapse. How these events influence subsequent gene expression and effector function is unclear. We studied the role of WASp in CD4+ T cell effe...

Trehalose, an easy, safe and efficient cryoprotectant for the parasitic protozoan Trypanosoma brucei.

PubMed

Wen, Yan-Zi; Su, Bi-Xiu; Lyu, Shu-Shen; Hide, Geoff; Lun, Zhao-Rong; Lai, De-Hua

2016-12-01

Trehalose, a non-permeating cryoprotective agent (CPA), has been documented as less toxic and highly efficient at cryopreserving different kinds of cells or organisms. In the present study, trehalose was evaluated for its application in cryopreservation of both Trypanosoma brucei procyclic and bloodstream form cells. The cryopreservation efficiency was determined by the motility of trypanosomes after thawing, as well as a subsequent recovery and infectivity assessment. The viability of trypanosomes from cultivation that were frozen in a serial concentrations of trehalose showed similar results to classical CPAs of glycerol and DMSO. Nevertheless, trypanosomes cryopreserved in 0.2M trehalose showed the best growth characteristic during subsequent cultivation. In addition, CPA cocktails with trehalose and permeating CPA glycerol or DMSO were developed and evaluated. Interestingly, trypanosomes in host (mouse) blood cryopreserved in 0.4M trehalose plus 5% glycerol showed higher infectivity than those preserved in trehalose/DMSO cocktails as well as individually. Further investigations showed that, in comparison with slow freezing at -80°C, flash freezing in liquid nitrogen provided better cryopreservation for bloodstream form cells than slow freezing. In conclusion, trehalose is an easy, safe and efficient CPA for cryopreservation of T. brucei and potentially for other protozoan species and cells. Copyright © 2016 Elsevier B.V. All rights reserved.

The Intracellular Destiny of the Protein Corona: A Study on its Cellular Internalization and Evolution.

PubMed

Bertoli, Filippo; Garry, David; Monopoli, Marco P; Salvati, Anna; Dawson, Kenneth A

2016-11-22

It has been well established that the early stages of nanoparticle-cell interactions are governed, at least in part, by the layer of proteins and other biomolecules adsorbed and slowly exchanged with the surrounding biological media (biomolecular corona). Subsequent to membrane interactions, nanoparticles are typically internalized into the cell and trafficked along defined pathways such as, in many cases, the endolysosomal pathway. Indeed, if the original corona is partially retained on the nanoparticle surface, the biomolecules in this layer may play an important role in determining subsequent cellular processing. In this work, using a combination of organelle separation and fluorescence labeling of the initial extracellular corona, we clarify its intracellular evolution as nanoparticles travel within the cell. We show that specific proteins present in the original protein corona are retained on the nanoparticles until they accumulate in lysosomes, and, once there, they are degraded. We also report on how different bare surfaces (amino and carboxyl modified) affect the details of this evolution. One overarching discovery is that the same serum proteins can exhibit different intracellular processing when carried inside cells by nanoparticles, as components of their corona, compared to what is observed when they are transported freely from the extracellular medium.

Conditioning monitoring by microstructural evaluation of cumulative fatigue damage

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

Fukuoka, C.; Nakagawa, Y.G.; Lance, J.J.

1996-12-01

The objective of this work is to evaluate the damage induced below and above the fatigue limit ({Delta}{sigma}{sub t} = 360 MPa) in pressure vessel steels, such as SA508. Fatigue damage was induced in samples taken from an SA508 steel plate by various loading histories in order to examine the influence of prior cyclic loading below the fatigue limit. Cell-to-cell misorientation differences were measured by the selected area diffraction (SAD) method. Surface cracking was also studied by the replication method. Small cracks were observed after precycling both below and above the fatigue limit. It was, however, found that fatigue testmore » bars had a longer lifetime after precycling below the fatigue limit, while precycling above the fatigue limit caused other specimens to fail even when subsequently cycled below the fatigue limit. Cell-to-cell misorientation usually increases with accumulation of fatigue damage, but it was found that the misorientations measured after precycling below the fatigue limit decreased again at the beginning of the subsequent cycling above the fatigue limit. It should be noted that the misorientation at failure was always about 4 to 5 deg, regardless of loading histories. Misorientation showed good correlation with the fatigue lifetime of the samples.« less

Estrogen receptor-mediated effects of a xenoestrogen, bisphenol A, on preimplantation mouse embryos.

PubMed

Takai, Y; Tsutsumi, O; Ikezuki, Y; Hiroi, H; Osuga, Y; Momoeda, M; Yano, T; Taketani, Y

2000-04-21

The effects of bisphenol A, a xenoestrogen widely used in industry and dentistry, were studied in early preimplantation mouse embryos. Two-cell mouse embryos were cultured with 100 pM to 100 microM bisphenol A with or without 100 nM tamoxifen and evaluated at 24-h intervals for their development to eight-cell and blastocyst stages. At 72 h, blastocysts were cultured for another 48 h without bisphenol A, and surface areas of trophoblast spread were measured. At 24 h, more embryos exposed to 3 nM bisphenol A than to controls had reached the eight-cell stage. At 48 h, more embryos exposed to 1 nM and 3 nM bisphenol A than to controls had become blastocysts. At 100 microM, bisphenol A decreased frequency of development to blastocysts. Tamoxifen counteracted both stimulatory and inhibitory effects of bisphenol A on blastocyst formation. Although bisphenol A did not alter blastocyst morphology or cell number, early exposure to 100 microM bisphenol A increased subsequent trophoblast areas. These findings suggest that bisphenol A may not only effect early embryonic development via estrogen receptors even at low, environmentally relevant doses, but also exert some late effects on subsequent development of these embryos. Copyright 2000 Academic Press.

Pancreatic Fat Accumulation, Fibrosis, and Acinar Cell Injury in the Zucker Diabetic Fatty Rat Fed a Chronic High-Fat Diet

PubMed Central

Matsuda, Akiko; Makino, Naohiko; Tozawa, Tomohiro; Shirahata, Nakao; Honda, Teiichiro; Ikeda, Yushi; Sato, Hideyuki; Ito, Miho; Kakizaki, Yasuharu; Akamatsu, Manabu; Ueno, Yoshiyuki; Kawata, Sumio

2014-01-01

Objective The histological alteration of the exocrine pancreas in obesity has not been clarified. In the present study, we investigated biochemical and histological changes in the exocrine pancreas of obese model rats. Methods Zucker lean rats were fed a standard diet, and Zucker diabetic fatty (ZDF) rats were divided into 2 groups fed a standard diet and a high-fat diet, respectively. These experimental groups were fed each of the diets from 6 weeks until 12, 18, 24 weeks of age. We performed blood biochemical assays and histological analysis of the pancreas. Results In the ZDF rats fed a high-fat diet, the ratio of accumulated pancreatic fat area relative to exocrine gland area was increased significantly at 18 weeks of age in comparison with the other 2 groups (P < 0.05), and lipid droplets were observed in acinar cells. Subsequently, at 24 weeks of age in this group, pancreatic fibrosis and the serum exocrine pancreatic enzyme levels were increased significantly relative to the other 2 groups (P < 0.01). Conclusions In ZDF rats fed a chronic high-fat diet, fat accumulates in pancreatic acinar cells, and this fatty change seems to be related to subsequent pancreatic fibrosis and acinar cell injury. PMID:24717823

Contribution of macrophages in the contrast loss in iron oxide-based MRI cancer cell tracking studies

PubMed Central

Danhier, Pierre; Deumer, Gladys; Joudiou, Nicolas; Bouzin, Caroline; Levêque, Philippe; Haufroid, Vincent; Jordan, Bénédicte F.; Feron, Olivier; Sonveaux, Pierre; Gallez, Bernard

2017-01-01

Magnetic resonance imaging (MRI) cell tracking of cancer cells labeled with superparamagnetic iron oxides (SPIO) allows visualizing metastatic cells in preclinical models. However, previous works showed that the signal void induced by SPIO on T2(*)-weighted images decreased over time. Here, we aim at characterizing the fate of iron oxide nanoparticles used in cell tracking studies and the role of macrophages in SPIO metabolism. In vivo MRI cell tracking of SPIO positive 4T1 breast cancer cells revealed a quick loss of T2* contrast after injection. We next took advantage of electron paramagnetic resonance (EPR) spectroscopy and inductively coupled plasma mass spectroscopy (ICP-MS) for characterizing the evolution of superparamagnetic and non-superparamagnetic iron pools in 4T1 breast cancer cells and J774 macrophages after SPIO labeling. These in vitro experiments and histology studies performed on 4T1 tumors highlighted the quick degradation of iron oxides by macrophages in SPIO-based cell tracking experiments. In conclusion, the release of SPIO by dying cancer cells and the subsequent uptake of iron oxides by tumor macrophages are limiting factors in MRI cell tracking experiments that plead for the use of (MR) reporter-gene based imaging methods for the long-term tracking of metastatic cells. PMID:28467814

Mechanisms of mechanical strain memory in airway smooth muscle.

PubMed

Kim, Hak Rim; Hai, Chi-Ming

2005-10-01

We evaluated the hypothesis that mechanical deformation of airway smooth muscle induces structural remodeling of airway smooth muscle cells, thereby modulating mechanical performance in subsequent contractions. This hypothesis implied that past experience of mechanical deformation was retained (or "memorized") as structural changes in airway smooth muscle cells, which modulated the cell's subsequent contractile responses. We termed this phenomenon mechanical strain memory. Preshortening has been found to induce attenuation of both force and isotonic shortening velocity in cholinergic receptor-activated airway smooth muscle. Rapid stretching of cholinergic receptor-activated airway smooth muscle from an initial length to a final length resulted in post-stretch force and myosin light chain phosphorylation that correlated significantly with initial length. Thus post-stretch muscle strips appeared to retain memory of the initial length prior to rapid stretch (mechanical strain memory). Cytoskeletal recruitment of actin- and integrin-binding proteins and Erk 1/2 MAPK appeared to be important mechanisms of mechanical strain memory. Sinusoidal length oscillation led to force attenuation during oscillation and in subsequent contractions in intact airway smooth muscle, and p38 MAPK appeared to be an important mechanism. In contrast, application of local mechanical strain to cultured airway smooth muscle cells induced local actin polymerization and cytoskeletal stiffening. It is conceivable that deep inspiration-induced bronchoprotection may be a manifestation of mechanical strain memory such that mechanical deformation from past breathing cycles modulated the mechanical performance of airway smooth muscle in subsequent cycles in a continuous and dynamic manner.

Clinical significance of intercellular contact at the four-cell stage of human embryos, and the use of abnormal cleavage patterns to identify embryos with low implantation potential: a time-lapse study.

PubMed

Liu, Yanhe; Chapple, Vincent; Feenan, Katie; Roberts, Peter; Matson, Phillip

2015-06-01

To investigate the clinical significance of intercellular contact point (ICCP) in four-cell stage human embryos and the effectiveness of morphology and abnormal cleavage patterns in identifying embryos with low implantation potential. Retrospective cohort study. Private IVF center. A total of 223 consecutive IVF and intracytoplasmic sperm injection treatment cycles, with all resulting embryos cultured in the Embryoscope, and a subset of 207 cycles analyzed for ICCP number where good-quality four-cell embryos were available on day 2 (n = 373 IVF and n = 392 intracytoplasmic sperm injection embryos). None. Morphologic score on day 3, embryo morphokinetic parameters, incidence of abnormal biological events, and known implantation results. Of 765 good-quality four-cell embryos, 89 (11.6%) failed to achieve six ICCPs; 166 of 765 (21.7%) initially had fewer than six ICCPs but were able to establish six ICCPs before subsequent division. Embryos with fewer than six ICCPs at the end of four-cell stage had a lower implantation rate (5.0% vs. 38.5%), with lower embryology performance in both conventional and morphokinetic assessments, compared with embryos achieving six ICCPs by the end of four-cell stage. Deselecting embryos with poor morphology, direct cleavage, reverse cleavage, and fewer than six ICCPs at the four-cell stage led to a significantly improved implantation rate (33.6% vs. 22.4%). Embryos with fewer than six ICCPs at the end of the four-cell stage show compromised subsequent development and reduced implantation potential. Deselection of embryos with poor morphology and abnormal cleavage revealed via time-lapse imaging could provide the basis of a qualitative algorithm for embryo selection. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Different profiles of neuroendocrine cell differentiation evolve in the PC-310 human prostate cancer model during long-term androgen deprivation.

PubMed

Jongsma, Johan; Oomen, Monique H; Noordzij, Marinus A; Van Weerden, Wytske M; Martens, Gerard J M; van der Kwast, Theodorus H; Schröder, Fritz H; van Steenbrugge, Gert J

2002-03-01

Neuroendocrine (NE) cells are androgen-independent cells and secrete growth-modulating peptide hormones via a regulated secretory pathway (RSP). We studied NE differentiation after long-term androgen withdrawal in the androgen-dependent human prostate cancer xenograft PC-310. Tumor-bearing nude mice were killed at 0, 2, 5, 7, 14, 21, 47, 84, and 154 days after castration. The half-life of the PC-310 tumor was 10 days, with a stable residual tumor volume of 30--40% after 21 days and longer periods of androgen deprivation. Proliferative activity and prostate-specific antigen serum levels decreased to zero after castration, whereas cell-cycle arrest was manifested by increased p27(kip1) expression. A temporary downregulation of androgen receptor (AR) expression was noted after androgen deprivation. The expression of chromogranin A, secretogranin III, and secretogranin V (7B2) increased 5 days after castration and later. Subsequently, pro-hormone convertase 1 and peptidyl alpha--amidating monooxygenase as well as vascular endothelial growth factor were expressed from 7 days after castration on. Finally, such growth factors as gastrin-releasing peptide and serotonin were expressed in a small part of the NE cells 21 days after castration, but strong expression was induced late during androgen deprivation, that is, 84 and 154 days after castration, respectively. Androgen deprivation of the NE-differentiated PC-310 model induced the formation of NE-differentiated AR(minus sign) and non-NE AR(+) tumor residues. The NE-differentiated cells actively produced growth factors via an RSP that may lead to hormone-refractory disease. The dormant non-NE AR(+) tumor cells were shown to remain androgen sensitive even after long-term androgen deprivation. In the PC-310 xenograft, time-dependent NE differentiation and subsequent maturation were induced after androgen depletion. The androgen-dependent PC-310 xenograft model constitutes an excellent model for studying the role of NE cells in the progression of clinical prostate cancer. Copyright 2002 Wiley-Liss, Inc.

Quantification and visualization of glutathione S-transferase omega 1 in cells using inductively coupled plasma mass spectrometry (ICP-MS) and fluorescence microscopy.

PubMed

Liang, Yong; Jiang, Xin; Tang, Nannan; Yang, Limin; Chen, Haifeng; Wang, Qiuquan

2015-03-01

We report a novel activity-based and Cu-free click chemistry (CC) mediated methodology for glutathione S-transferase omega 1 (GSTO1) quantification using species-unspecific isotope dilution inductively coupled plasma mass spectrometry (SUID ICP-MS), in which dibenzylcyclooctyne-modified 2-chloroacetamide (DBCO-ChAcA) was designed and synthesized, meanwhile, as a navigator towards GSTO1 for subsequent N3-DOTA-Eu-tagging via Cu-free CC. Using (153)Eu-SUID ICP-MS coupled with size exclusion chromatography (SEC), the LOD (3σ) of GSTO1 reached 6.9 fmol with an RSD of 2.4% at the 0.1 μM level (n = 5) considering the recovery of GSTO1 on the SEC was 96.5 ± 2.4%. The GSTO1 contents in the cells of human hepatocellular carcinoma C7721 and breast carcinoma MCF-7 as well as normal hepatic C7701 without or with cis-platin administration were quantified to be from 1.2 μg/10,000 cells (n = 3, RSD = 4.5%) corresponding to 1.2 × 10(-2) ng per cell to 4.76 μg/10,000 cells (n = 3, RSD = 2.9%) corresponding to 4.76 × 10(-2) ng per cell. For a comparative study, DBCO-ChAcA-fluor 488-based fluorescence microscopy could not alone visualize GSTO1 in the cells but could together with those from the small SH-containing molecules such as GSH and that from extra N3-fluor 488 in the cells. This activity-based CC-mediated tagging/labeling strategy provided an opportunity for ICP-MS-based targeted protein quantification, and is very much expected to find its applications in biological mechanism study and the subsequent drug design.

Osteoclasts control reactivation of dormant myeloma cells by remodelling the endosteal niche

PubMed Central

Lawson, Michelle A.; McDonald, Michelle M.; Kovacic, Natasa; Hua Khoo, Weng; Terry, Rachael L.; Down, Jenny; Kaplan, Warren; Paton-Hough, Julia; Fellows, Clair; Pettitt, Jessica A.; Neil Dear, T.; Van Valckenborgh, Els; Baldock, Paul A.; Rogers, Michael J.; Eaton, Colby L.; Vanderkerken, Karin; Pettit, Allison R.; Quinn, Julian M. W.; Zannettino, Andrew C. W.; Phan, Tri Giang; Croucher, Peter I.

2015-01-01

Multiple myeloma is largely incurable, despite development of therapies that target myeloma cell-intrinsic pathways. Disease relapse is thought to originate from dormant myeloma cells, localized in specialized niches, which resist therapy and repopulate the tumour. However, little is known about the niche, and how it exerts cell-extrinsic control over myeloma cell dormancy and reactivation. In this study, we track individual myeloma cells by intravital imaging as they colonize the endosteal niche, enter a dormant state and subsequently become activated to form colonies. We demonstrate that dormancy is a reversible state that is switched ‘on' by engagement with bone-lining cells or osteoblasts, and switched ‘off' by osteoclasts remodelling the endosteal niche. Dormant myeloma cells are resistant to chemotherapy that targets dividing cells. The demonstration that the endosteal niche is pivotal in controlling myeloma cell dormancy highlights the potential for targeting cell-extrinsic mechanisms to overcome cell-intrinsic drug resistance and prevent disease relapse. PMID:26632274

Pioneer neurog1 expressing cells ingress into the otic epithelium and instruct neuronal specification

PubMed Central

Hoijman, Esteban; Fargas, L; Blader, Patrick; Alsina, Berta

2017-01-01

Neural patterning involves regionalised cell specification. Recent studies indicate that cell dynamics play instrumental roles in neural pattern refinement and progression, but the impact of cell behaviour and morphogenesis on neural specification is not understood. Here we combine 4D analysis of cell behaviours with dynamic quantification of proneural expression to uncover the construction of the zebrafish otic neurogenic domain. We identify pioneer cells expressing neurog1 outside the otic epithelium that migrate and ingress into the epithelialising placode to become the first otic neuronal progenitors. Subsequently, neighbouring cells express neurog1 inside the placode, and apical symmetric divisions amplify the specified pool. Interestingly, pioneer cells delaminate shortly after ingression. Ablation experiments reveal that pioneer cells promote neurog1 expression in other otic cells. Finally, ingression relies on the epithelialisation timing controlled by FGF activity. We propose a novel view for otic neurogenesis integrating cell dynamics whereby ingression of pioneer cells instructs neuronal specification. DOI: http://dx.doi.org/10.7554/eLife.25543.001 PMID:28537554

Electro-triggering and electrochemical monitoring of dopamine exocytosis from a single cell by using ultrathin electrodes based on Au nanowires

NASA Astrophysics Data System (ADS)

Kang, Mijeong; Yoo, Seung Min; Gwak, Raekeun; Eom, Gayoung; Kim, Jihwan; Lee, Sang Yup; Kim, Bongsoo

2015-12-01

A sophisticated set of an Au nanowire (NW) stimulator-Au NW detector system is developed for electrical cell stimulation and electrochemical analysis of subsequent exocytosis with very high spatial resolution. Dopamine release from a rat pheochromocytoma cell is more stimulated by a more negative voltage pulse. This system could help to improve the therapeutic efficacy of electrotherapies by providing valuable information on their healing mechanism.A sophisticated set of an Au nanowire (NW) stimulator-Au NW detector system is developed for electrical cell stimulation and electrochemical analysis of subsequent exocytosis with very high spatial resolution. Dopamine release from a rat pheochromocytoma cell is more stimulated by a more negative voltage pulse. This system could help to improve the therapeutic efficacy of electrotherapies by providing valuable information on their healing mechanism. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06021d

Establishing a reference dataset for the authentication of spinal muscular atrophy cell lines using STR profiling and digital PCR.

PubMed

Stabley, Deborah L; Holbrook, Jennifer; Harris, Ashlee W; Swoboda, Kathryn J; Crawford, Thomas O; Sol-Church, Katia; Butchbach, Matthew E R

2017-05-01

Fibroblasts and lymphoblastoid cell lines (LCLs) derived from individuals with spinal muscular atrophy (SMA) have been and continue to be essential for translational SMA research. Authentication of cell lines helps ensure reproducibility and rigor in biomedical research. This quality control measure identifies mislabeling or cross-contamination of cell lines and prevents misinterpretation of data. Unfortunately, authentication of SMA cell lines used in various studies has not been possible because of a lack of a reference. In this study, we provide said reference so that SMA cell lines can be subsequently authenticated. We use short tandem repeat (STR) profiling and digital PCR (dPCR), which quantifies SMN1 and SMN2 copy numbers, to generate molecular identity codes for fibroblasts and LCLs that are commonly used in SMA research. Using these molecular identity codes, we clarify the familial relationships within a set of fibroblasts commonly used in SMA research. This study presents the first cell line reference set for the SMA research community and demonstrates its usefulness for re-identification and authentication of lines commonly used as in vitro models for future studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Spiral ganglion degeneration and hearing loss as a consequence of satellite cell death in saposin B-deficient mice.

PubMed

Akil, Omar; Sun, Ying; Vijayakumar, Sarath; Zhang, Wujuan; Ku, Tiffany; Lee, Chi-Kyou; Jones, Sherri; Grabowski, Gregory A; Lustig, Lawrence R

2015-02-18

Saposin B (Sap B) is an essential activator protein for arylsulfatase A in the hydrolysis of sulfatide, a lipid component of myelin. To study Sap B's role in hearing and balance, a Sap B-deficient (B(-/-)) mouse was evaluated. At both light and electron microscopy (EM) levels, inclusion body accumulation was seen in satellite cells surrounding spiral ganglion (SG) neurons from postnatal month 1 onward, progressing into large vacuoles preceding satellite cell degeneration, and followed by SG degeneration. EM also revealed reduced or absent myelin sheaths in SG neurons from postnatal month 8 onwards. Hearing loss was initially seen at postnatal month 6 and progressed thereafter for frequency-specific stimuli, whereas click responses became abnormal from postnatal month 13 onward. The progressive hearing loss correlated with the accumulation of inclusion bodies in the satellite cells and their subsequent degeneration. Outer hair cell numbers and efferent function measures (distortion product otoacoustic emissions and contralateral suppression) were normal in the B(-/-) mice throughout this period. Alcian blue staining of SGs demonstrated that these inclusion bodies corresponded to sulfatide accumulation. In contrast, changes in the vestibular system were much milder, but caused severe physiologic deficits. These results demonstrate that loss of Sap B function leads to progressive sulfatide accumulation in satellite cells surrounding the SG neurons, leading to satellite cell degeneration and subsequent SG degeneration with a resultant loss of hearing. Relative sparing of the efferent auditory and vestibular neurons suggests that alternate glycosphingolipid metabolic pathways predominate in these other systems. Copyright © 2015 the authors 0270-6474/15/353263-13$15.00/0.

Downregulation of a mitochondria associated protein SLP-2 inhibits tumor cell motility, proliferation and enhances cell sensitivity to chemotherapeutic reagents.

PubMed

Wang, Yueqi; Cao, Wenfeng; Yu, Zaicheng; Liu, Zhihua

2009-09-01

Results from tissue microarray in this study and our previous reports revealed that stomatin-like protein 2 (SLP-2) is notably associated with tumorigenesis and metastasis. Many members of stomatin family are involved in tumor as mitochondrial component, and recent study has revealed that SLP-2 may also function in mitochondria. To further investigate the function of SLP-2, we used siRNA target SLP-2. Data showed that knock-down of SLP-2 potently inhibited cell motility, proliferation and slightly altered cell cycle without any significant change of apoptosis. Moreover, by combined application with different chemotherapeutic reagents, we observed the enhancement of cell chemosensitivity by SLP-2 depletion. We also confirmed that, SLP-2 localizes in mitochondria, affects mitochondrial membrane potential (MMP) and ATP production. We conclude that, SLP-2 is a mitochondrial protein and therefore, functions in energy process by MMP maintenance, and subsequently affecting cell motility, proliferation and chemosensitivity.

Application of an improved magnetic immunosorbent in an Ephesia chip designed for circulating tumor cell capture.

PubMed

Svobodova, Zuzana; Kucerova, Jana; Autebert, Julien; Horak, Daniel; Bruckova, Lenka; Viovy, Jean-Louis; Bilkova, Zuzana

2014-02-01

In this study, we describe a particular step in developing a microfluidic device for capture and detection of circulating tumor cells-specifically the preparation of an immunosorbent for implementation into the separation chip. We highlight some of the most important specifics connected with superparamegnetic microspheres for microfluidic purposes. Factors such as nonspecific adsorption on microfluidic channels, interactions with model cell lines, and tendency to aggregation were investigated. Poly(glycidyl methacrylate) microspheres with carboxyl groups were employed for this purpose. To address the aforementioned challenges, the microspheres were coated with hydrazide-PEG-hydrazide, and subsequently anti-epithelial cell adhesion molecule (EpCAM) antibody was immobilized. The prepared anti-EpCAM immunosorbent was pretested using model cell lines with differing EpCAM density (MCF7, SKBR3, A549, and Raji) in a batchwise arrangement. Finally, the entire system was implemented and studied in an Ephesia chip and an evaluation was performed by the MCF7 cell line. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Temporal Chromatin Signature in Human Embryonic Stem Cells Identifies Regulators of Cardiac Development

PubMed Central

Paige, Sharon L.; Thomas, Sean; Stoick-Cooper, Cristi L.; Wang, Hao; Maves, Lisa; Sandstrom, Richard; Pabon, Lil; Reinecke, Hans; Pratt, Gabriel; Keller, Gordon; Moon, Randall T.; Stamatoyannopoulos, John; Murry, Charles E.

2012-01-01

Summary Directed differentiation of human embryonic stem cells (ESCs) into cardiovascular cells provides a model for studying molecular mechanisms of human cardiovascular development. Though it is known that chromatin modification patterns in ESCs differ markedly from those in lineage-committed progenitors and differentiated cells, the temporal dynamics of chromatin alterations during differentiation along a defined lineage have not been studied. We show that differentiation of human ESCs into cardiovascular cells is accompanied by programmed temporal alterations in chromatin structure that distinguish key regulators of cardiovascular development from other genes. We used this temporal chromatin signature to identify regulators of cardiac development, including the homeobox gene MEIS2. We demonstrate using the zebrafish model that MEIS2 is critical for proper heart tube formation and subsequent cardiac looping. Temporal chromatin signatures should be broadly applicable to other models of stem cell differentiation to identify regulators and provide key insights into major developmental decisions. PMID:22981225

A potential inhibitory function of draxin in regulating mouse trunk neural crest migration.

PubMed

Zhang, Sanbing; Su, Yuhong; Gao, Jinbao; Zhang, Chenbing; Tanaka, Hideaki

2017-01-01

Draxin is a repulsive axon guidance protein that plays important roles in the formation of three commissures in the central nervous system and dorsal interneuron 3 (dI3) in the chick spinal cord. In the present study, we report the expression pattern of mouse draxin in the embryonic mouse trunk spinal cord. In the presence of draxin, the longest net migration length of a migrating mouse trunk neural crest cell was significantly reduced. In addition, the relative number of apolar neural crest cells increased as the draxin treatment time increased. Draxin caused actin cytoskeleton rearrangement in the migrating trunk neural crest cells. Our data suggest that draxin may regulate mouse trunk neural crest cell migration by the rearrangement of cell actin cytoskeleton and by reducing the polarization activity of these cells subsequently.

Self-contained high-pressure cell, apparatus, and procedure for the preparation of encapsulated proteins dissolved in low viscosity fluids for nuclear magnetic resonance spectroscopy

NASA Astrophysics Data System (ADS)

Peterson, Ronald W.; Wand, A. Joshua

2005-09-01

The design of a sample cell for high-performance nuclear magnetic resonance (NMR) at elevated pressure is described. The cell has been optimized for the study of encapsulated proteins dissolved in low viscosity fluids but is suitable for more general nuclear magnetic resonance (NMR) spectroscopy of biomolecules at elevated pressure. The NMR cell is comprised of an alumina-toughened zirconia tube mounted on a self-sealing nonmagnetic metallic valve. The cell has several advantages, including relatively low cost, excellent NMR performance, high-pressure tolerance, chemical inertness, and a relatively large active volume. Also described is a low volume sample preparation device that allows for the preparation of samples under high hydrostatic pressure and their subsequent transfer to the NMR cell.

Quantitative High-Resolution Genomic Analysis of Single Cancer Cells

PubMed Central

Hannemann, Juliane; Meyer-Staeckling, Sönke; Kemming, Dirk; Alpers, Iris; Joosse, Simon A.; Pospisil, Heike; Kurtz, Stefan; Görndt, Jennifer; Püschel, Klaus; Riethdorf, Sabine; Pantel, Klaus; Brandt, Burkhard

2011-01-01

During cancer progression, specific genomic aberrations arise that can determine the scope of the disease and can be used as predictive or prognostic markers. The detection of specific gene amplifications or deletions in single blood-borne or disseminated tumour cells that may give rise to the development of metastases is of great clinical interest but technically challenging. In this study, we present a method for quantitative high-resolution genomic analysis of single cells. Cells were isolated under permanent microscopic control followed by high-fidelity whole genome amplification and subsequent analyses by fine tiling array-CGH and qPCR. The assay was applied to single breast cancer cells to analyze the chromosomal region centred by the therapeutical relevant EGFR gene. This method allows precise quantitative analysis of copy number variations in single cell diagnostics. PMID:22140428

The polarity protein Baz forms a platform for the centrosome orientation during asymmetric stem cell division in the Drosophila male germline.

PubMed

Inaba, Mayu; Venkei, Zsolt G; Yamashita, Yukiko M

2015-03-20

Many stem cells divide asymmetrically in order to balance self-renewal with differentiation. The essence of asymmetric cell division (ACD) is the polarization of cells and subsequent division, leading to unequal compartmentalization of cellular/extracellular components that confer distinct cell fates to daughter cells. Because precocious cell division before establishing cell polarity would lead to failure in ACD, these two processes must be tightly coupled; however, the underlying mechanism is poorly understood. In Drosophila male germline stem cells, ACD is prepared by stereotypical centrosome positioning. The centrosome orientation checkpoint (COC) further serves to ensure ACD by preventing mitosis upon centrosome misorientation. In this study, we show that Bazooka (Baz) provides a platform for the correct centrosome orientation and that Baz-centrosome association is the key event that is monitored by the COC. Our work provides a foundation for understanding how the correct cell polarity may be recognized by the cell to ensure productive ACD.

Isolation, separation, and characterization of epithelial and connective cells from rat palate

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

Terranova, Victor Paul

1979-01-01

Epithelial and connective tissue cells were isolated from rat palate by sequential collagenase, hyaluronidase and trypsin digestion of the extracellular matrix. Differences between the two populations were noted with respect to total cell protein, total cell water, proline uptake and incorporation, percent collagen synthesized, effects of parathyroid hormone, metabolism of D-valine and cell density. Basal epithelial cells were subsequently separated from the heterogeneous epithelial cell population on shallow linear density gradients by velocity centrifugation. The type of collagen synthesized by the basal epithelial cells was compared to the type of collagen synthesized by the connective tissue cells by means ofmore » labeled amino acid incorporation ratios. Cells isolated from the epithelial and connective tissue were compared. From these studies it can be concluded that epithelial and connective tissue cells can be isolated from rat palate as viable and distinct populations with respect to the biochemical parameters examined. Furthermore, subpopulations can be separated and biochemically characterized.« less

Immunophenotypic characterization of the cutaneous exanthem of SIV-infected rhesus monkeys. Apposition of degenerative Langerhans cells and cytotoxic lymphocytes during the development of acquired immunodeficiency syndrome.

PubMed Central

Ringler, D. J.; Hancock, W. W.; King, N. W.; Letvin, N. L.; Daniel, M. D.; Desrosiers, R. C.; Murphy, G. F.

1987-01-01

A T-cell tropic retrovirus, simian immunodeficiency virus (SIV), has recently been isolated from immunodeficient rhesus monkeys. This virus has remarkable similarities to human immunodeficiency virus (HIV), the etiologic agent of acquired immunodeficiency syndrome. Subsequent studies of simian infection with SIV have shown it to be a relevant animal model for studying the pathogenesis of AIDS in man. In both HIV-infected humans and SIV-infected monkeys, a cutaneous maculopapular eruption has been described. To date, the pathogenesis and possible relationship of these exanthema to the evolution of systemic immunosuppression have remained obscure. In this study, the mononuclear cell infiltrates that characterize skin rashes of SIV-infected rhesus monkeys were found to be composed predominantly of cells with phenotypic characteristics of cytotoxic/suppressor (T8+) lymphocytes and natural killer cells. Many of these cells expressed membrane-bound interleukin-2 receptor molecules. Double labeling and immunoelectron microscopy revealed these cells in direct contact with degenerative Langerhans cells within the epidermis and dermis. These observations suggest that the cutaneous rash associated with SIV infection may be the consequence of target cell injury of Langerhans cells by effector cells with cytotoxic potential. Images Figure 1 Figure 2 Figure 3 PMID:3030113

Cell adhesion and mechanics as drivers of tissue organization and differentiation: local cues for large scale organization.

PubMed

Wickström, Sara A; Niessen, Carien M

2018-06-01

Biological patterns emerge through specialization of genetically identical cells to take up distinct fates according to their position within the organism. How initial symmetry is broken to give rise to these patterns remains an intriguing open question. Several theories of patterning have been proposed, most prominently Turing's reaction-diffusion model of a slowly diffusing activator and a fast diffusing inhibitor generating periodic patterns. Although these reaction-diffusion systems can generate diverse patterns, it is becoming increasingly evident that cell shape and tension anisotropies, mediated via cell-cell and/or cell-matrix contacts, also facilitate symmetry breaking and subsequent self-organized tissue patterning. This review will highlight recent studies that implicate local changes in adhesion and/or tension as key drivers of cell rearrangements. We will also discuss recent studies on the role of cadherin and integrin adhesive receptors in mediating and responding to local tissue tension asymmetries to coordinate cell fate, position and behavior essential for tissue self-organization and maintenance. Copyright © 2018 Elsevier Ltd. All rights reserved.

Role of the p55-gamma subunit of PI3K in ALK-induced cell migration: RNAi-based selection of cell migration regulators.

PubMed

Seo, Minchul; Kim, Jong-Heon; Suk, Kyoungho

2017-05-04

Recently, unbiased functional genetic selection identified novel cell migration-regulating genes. This RNAi-based functional selection was performed using 63,996 pooled lentiviral shRNAs targeting 21,332 mouse genes. After five rounds of selection using cells with accelerated or impaired migration, shRNAs were retrieved and identified by half-hairpin barcode sequencing using cells with the selected phenotypes. This selection process led to the identification of 29 novel cell migration regulators. One of these candidates, anaplastic lymphoma kinase (ALK), was further investigated. Subsequent studies revealed that ALK promoted cell migration through the PI3K-AKT pathway via the p55γ regulatory subunit of PI3K, rather than more commonly used p85 subunit. Western blot and immunohistochemistry studies using mouse brain tissues revealed similar temporal expression patterns of ALK, phospho-p55γ, and phospho-AKT during different stages of development. These data support an important role for the p55γ subunit of PI3K in ALK-induced cell migration during brain development.

X-linked Inhibitor of Apoptosis Protein (XIAP) Mediates Cancer Cell Motility via Rho GDP Dissociation Inhibitor (RhoGDI)-dependent Regulation of the Cytoskeleton*

PubMed Central

Liu, Jinyi; Zhang, Dongyun; Luo, Wenjing; Yu, Yonghui; Yu, Jianxiu; Li, Jingxia; Zhang, Xinhai; Zhang, Baolin; Chen, Jingyuan; Wu, Xue-Ru; Rosas-Acosta, Germán; Huang, Chuanshu

2011-01-01

X-linked inhibitor of apoptosis protein (XIAP) overexpression has been found to be associated with malignant cancer progression and aggression in individuals with many types of cancers. However, the molecular basis of XIAP in the regulation of cancer cell biological behavior remains largely unknown. In this study, we found that a deficiency of XIAP expression in human cancer cells by either knock-out or knockdown leads to a marked reduction in β-actin polymerization and cytoskeleton formation. Consistently, cell migration and invasion were also decreased in XIAP-deficient cells compared with parental wild-type cells. Subsequent studies demonstrated that the regulation of cell motility by XIAP depends on its interaction with the Rho GDP dissociation inhibitor (RhoGDI) via the XIAP RING domain. Furthermore, XIAP was found to negatively regulate RhoGDI SUMOylation, which might affect its activity in controlling cell motility. Collectively, our studies provide novel insights into the molecular mechanisms by which XIAP regulates cancer invasion and offer a further theoretical basis for setting XIAP as a potential prognostic marker and specific target for treatment of cancers with metastatic properties. PMID:21402697

T Cells that Recognize HPV Protein Can Target Virus-Infected Cells | Center for Cancer Research

Cancer.gov

Treating patients with T cells isolated from a tumor and subsequently expanded in the lab can cause the complete regression of some melanomas and cervical cancers, but the treatment is currently restricted to a few cancer types.

Nanohybrids with Magnetic and Persistent Luminescence Properties for Cell Labeling, Tracking, In Vivo Real-Time Imaging, and Magnetic Vectorization.

PubMed

Teston, Eliott; Maldiney, Thomas; Marangon, Iris; Volatron, Jeanne; Lalatonne, Yoann; Motte, Laurence; Boisson-Vidal, Catherine; Autret, Gwennhael; Clément, Olivier; Scherman, Daniel; Gazeau, Florence; Richard, Cyrille

2018-04-01

Once injected into a living organism, cells diffuse or migrate around the initial injection point and become impossible to be visualized and tracked in vivo. The present work concerns the development of a new technique for therapeutic cell labeling and subsequent in vivo visualization and magnetic retention. It is hypothesized and subsequently demonstrated that nanohybrids made of persistent luminescence nanoparticles and ultrasmall superparamagnetic iron oxide nanoparticles incorporated into a silica matrix can be used as an effective nanoplatform to label therapeutic cells in a nontoxic way in order to dynamically track them in real-time in vitro and in living mice. As a proof-of-concept, it is shown that once injected, these labeled cells can be visualized and attracted in vivo using a magnet. This first step suggests that these nanohybrids represent efficient multifunctional nanoprobes for further imaging guided cell therapies development. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Large-Scale Femtoliter Droplet Array for Single Cell Efflux Assay of Bacteria.

PubMed

Iino, Ryota; Sakakihara, Shouichi; Matsumoto, Yoshimi; Nishino, Kunihiko

2018-01-01

Large-scale femtoliter droplet array as a platform for single cell efflux assay of bacteria is described. Device microfabrication, femtoliter droplet array formation and concomitant enclosure of single bacterial cells, fluorescence-based detection of efflux activity at the single cell level, and collection of single cells from droplet and subsequent gene analysis are described in detail.

Vitrification of mouse embryo-derived ICM cells: a tool for preserving embryonic stem cell potential?

PubMed

Desai, Nina; Xu, Jing; Tsulaia, Tamara; Szeptycki-Lawson, Julia; AbdelHafez, Faten; Goldfarb, James; Falcone, Tommaso

2011-02-01

Vitrification technology presents new opportunities for preservation of embryo derived stem cells without first establishing a viable ESC line. This study tests the feasibility of cryopreserving ICM cells using vitrification. ICMs from mouse embryos were isolated and vitrified in HSV straws or on cryoloops. Upon warming, the vitrified ICMs were cultured and observed for attachment and morphology. Colonies were passaged every 3-6 days. ICMs and ICM-derived ESC colonies were tested for expression of stem cell specific markers. ICMs vitrified on both the cryoloop and the HSV straw had high survival rates. ICM derived ESCs remained undifferentiated for several passages and demonstrated expression of typical stem cell markers; SSEA-1, Sox-2, Oct 4 and alkaline phosphatase. This is the first report on successful vitrification of isolated ICMs and the subsequent derivation of ESC colonies. Vitrification of isolated ICMs is a novel approach for preservation of the "stem cell source" material.

Commentary: on bone marrow stem cells and openmindedness.

PubMed

Mezey, Eva

2004-02-01

Several lines of evidence support the concept that pluripotent stem cells reside in the hematopoietic system of adults, but each has been questioned for valid reasons. Thus, the results reported to date after infusion of bone marrow stem cells, may be due to cell fusion, non-physiological de-differentiation and subsequent differentiation to lineages directed by the culture environment, microchimerism, or transdifferentiation. Several authors have suggested complex ways of investigating each of these possibilities, but in no case are any of the suggested protocols complete, nor will they rule out other possible causes of the results observed to date. Determining the nature, origin, and characteristics of adult cells is important and interesting, but the important question at this time is not what happens physiologically, but what we can do with these cells therapeutically. Research addressing therapeutic endpoints now takes a pivotal position in studies of nonembryonic stem cells.

Biofuel cell operating on activated THP-1 cells: A fuel and substrate study.

PubMed

Javor, Kristina; Tisserant, Jean-Nicolas; Stemmer, Andreas

2017-01-15

It is known that electrochemical energy can be harvested from mammalian cells, more specifically from white blood cells (WBC). This study focuses on an improved biofuel cell operating on phorbol myristate acetate (PMA) activated THP-1 human monocytic cells. Electrochemical investigation showed strong evidence pointing towards hydrogen peroxide being the primary current source, confirming that the current originates from NADPH oxidase activity. Moreover, an adequate substrate for differentiation and activation of THP-1 cells was examined. ITO, gold, platinum and glass were tested and the amount of superoxide anion produced by NADPH oxidase was measured by spectrophotometry through WST-1 reduction at 450nm and used as an indicator of cellular activity and viability. These substrates were subsequently used in a conventional two-compartment biofuel cell where the power density output was recorded. The material showing the highest cell activity compared to the reference cell culture plate and the highest power output was ITO. Under our experimental conditions, a power density of 4.5μW/cm 2 was reached. To the best of our knowledge, this is a threefold higher power output than other leukocyte biofuel cells. Copyright © 2016 Elsevier B.V. All rights reserved.

Morphological and genetical changes of endothelial progenitor cells after in-vitro conversion into photoreceptors.

PubMed

Qiang, Shi; Alsaeedi, Hiba Amer; Yuhong, Cheng; Yang, Hao; Tong, Li; Kumar, Suresh; Higuchi, Akon; Alarfaj, Abdullah A; Munisvaradass, Rusheni; Ling, Mok Pooi; Cheng, Pei

2018-06-01

Retinal degeneration is a condition ensued by various ocular disorders such as artery occlusion, diabetic retinopathy, retrolental fibroplasia and retinitis pigmentosa which cause abnormal loss of photoreceptor cells and lead to eventual vision impairment. No efficient treatment has yet been found, however, the use of stem cell therapy such as bone marrow and embryonic stem cells has opened a new treatment modality for retinal degenerative diseases. The major goal of this study is to analyze the potential of endothelial progenitor cells derived from bone marrow to differentiate into retinal neural cells for regenerative medicine purposes. In this study, endothelial progenitor cells were induced in-vitro with photoreceptor growth factor (taurine) for 21 days. Subsequently, the morphology and gene expression of CRX and RHO of the photoreceptors-induced EPCs were examined through immunostaining assay. The results indicated that the induced endothelial progenitor cells demonstrated positive gene expression of CRX and RHO. Our findings suggested that EPC cells may have a high advantage in cell replacement therapy for treating eye disease, in addition to other neural diseases, and may be a suitable cell source in regenerative medicine for eye disorders. Copyright © 2018 Elsevier B.V. All rights reserved.

Stem Cell Therapy for the Inner Ear

PubMed Central

Okano, Takayuki

2012-01-01

In vertebrates, perception of sound, motion, and balance is mediated through mechanosensory hair cells located within the inner ear. In mammals, hair cells are only generated during a short period of embryonic development. As a result, loss of hair cells as a consequence of injury, disease, or genetic mutation, leads to permanent sensory deficits. At present, cochlear implantation is the only option for profound hearing loss. However, outcomes are still variable and even the best implant cannot provide the acuity of a biological ear. The recent emergence of stem cell technology has the potential to open new approaches for hair cell regeneration. The goal of this review is to summarize the current state of inner ear stem cell research from a viewpoint of its clinical application for inner ear disorders to illustrate how complementary studies have the potential to promote and refine stem cell therapies for inner ear diseases. The review initially discusses our current understanding of the genetic pathways that regulate hair cell formation from inner ear progenitors during normal development. Subsequent sections discuss the possible use of endogenous inner ear stem cells to induce repair as well as the initial studies aimed at transplanting stem cells into the ear. PMID:22514095

Stem Cells as a Tool for Breast Imaging

PubMed Central

Padín-Iruegas, Maria Elena; López López, Rafael

2012-01-01

Stem cells are a scientific field of interest due to their therapeutic potential. There are different groups, depending on the differentiation state. We can find lonely stem cells, but generally they distribute in niches. Stem cells don't survive forever. They are affected for senescence. Cancer stem cells are best defined functionally, as a subpopulation of tumor cells that can enrich for tumorigenic property and can regenerate heterogeneity of the original tumor. Circulating tumor cells are cells that have detached from a primary tumor and circulate in the bloodstream. They may constitute seeds for subsequent growth of additional tumors (metastasis) in different tissues. Advances in molecular imaging have allowed a deeper understanding of the in vivo behavior of stem cells and have proven to be indispensable in preclinical and clinical studies. One of the first imaging modalities for monitoring pluripotent stem cells in vivo, magnetic resonance imaging (MRI) offers high spatial and temporal resolution to obtain detailed morphological and functional information. Advantages of radioscintigraphic techniques include their picomolar sensitivity, good tissue penetration, and translation to clinical applications. Radionuclide imaging is the sole direct labeling technique used thus far in human studies, involving both autologous bone marrow derived and peripheral stem cells. PMID:22848220

Lysophosphatidic acid triggers mast cell-driven atherosclerotic plaque destabilization by increasing vascular inflammation[S

PubMed Central

Bot, Martine; de Jager, Saskia C. A.; MacAleese, Luke; Lagraauw, H. Maxime; van Berkel, Theo J. C.; Quax, Paul H. A.; Kuiper, Johan; Heeren, Ron M. A.; Biessen, Erik A. L.; Bot, Ilze

2013-01-01

Lysophosphatidic acid (LPA), a bioactive lysophospholipid, accumulates in the atherosclerotic plaque. It has the capacity to activate mast cells, which potentially exacerbates plaque progression. In this study, we thus aimed to investigate whether LPA contributes to plaque destabilization by modulating mast cell function. We here show by an imaging mass spectrometry approach that several LPA species are present in atherosclerotic plaques. Subsequently, we demonstrate that LPA is a potent mast cell activator which, unlike other triggers, favors release of tryptase. Local perivascular administration of LPA to an atherosclerotic carotid artery segment increases the activation status of perivascular mast cells and promotes intraplaque hemorrhage and macrophage recruitment without impacting plaque cell apoptosis. The mast cell stabilizer cromolyn could prevent intraplaque hemorrhage elicited by LPA-mediated mast cell activation. Finally, the involvement of mast cells in these events was further emphasized by the lack of effect of perivascular LPA administration in mast cell deficient animals. We demonstrate that increased accumulation of LPA in plaques induces perivascular mast cell activation and in this way contributes to plaque destabilization in vivo. This study points to local LPA availability as an important factor in atherosclerotic plaque stability. PMID:23396975

Lysophosphatidic acid triggers mast cell-driven atherosclerotic plaque destabilization by increasing vascular inflammation.

PubMed

Bot, Martine; de Jager, Saskia C A; MacAleese, Luke; Lagraauw, H Maxime; van Berkel, Theo J C; Quax, Paul H A; Kuiper, Johan; Heeren, Ron M A; Biessen, Erik A L; Bot, Ilze

2013-05-01

Lysophosphatidic acid (LPA), a bioactive lysophospholipid, accumulates in the atherosclerotic plaque. It has the capacity to activate mast cells, which potentially exacerbates plaque progression. In this study, we thus aimed to investigate whether LPA contributes to plaque destabilization by modulating mast cell function. We here show by an imaging mass spectrometry approach that several LPA species are present in atherosclerotic plaques. Subsequently, we demonstrate that LPA is a potent mast cell activator which, unlike other triggers, favors release of tryptase. Local perivascular administration of LPA to an atherosclerotic carotid artery segment increases the activation status of perivascular mast cells and promotes intraplaque hemorrhage and macrophage recruitment without impacting plaque cell apoptosis. The mast cell stabilizer cromolyn could prevent intraplaque hemorrhage elicited by LPA-mediated mast cell activation. Finally, the involvement of mast cells in these events was further emphasized by the lack of effect of perivascular LPA administration in mast cell deficient animals. We demonstrate that increased accumulation of LPA in plaques induces perivascular mast cell activation and in this way contributes to plaque destabilization in vivo. This study points to local LPA availability as an important factor in atherosclerotic plaque stability.

Supercritical carbon dioxide extracted extracellular matrix material from adipose tissue.

PubMed

Wang, Jun Kit; Luo, Baiwen; Guneta, Vipra; Li, Liang; Foo, Selin Ee Min; Dai, Yun; Tan, Timothy Thatt Yang; Tan, Nguan Soon; Choong, Cleo; Wong, Marcus Thien Chong

2017-06-01

Adipose tissue is a rich source of extracellular matrix (ECM) material that can be isolated by delipidating and decellularizing the tissue. However, the current delipidation and decellularization methods either involve tedious and lengthy processes or require toxic chemicals, which may result in the elimination of vital proteins and growth factors found in the ECM. Hence, an alternative delipidation and decellularization method for adipose tissue was developed using supercritical carbon dioxide (SC-CO 2 ) that eliminates the need of any harsh chemicals and also reduces the amount of processing time required. The resultant SC-CO 2 -treated ECM material showed an absence of nuclear content but the preservation of key proteins such as collagen Type I, collagen Type III, collagen Type IV, elastin, fibronectin and laminin. In addition, other biological factors such as glycosaminoglycans (GAGs) and growth factors such as basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) were also retained. Subsequently, the resulting SC-CO 2 -treated ECM material was used as a bioactive coating on tissue culture plastic (TCP). Four different cell types including adipose tissue-derived mesenchymal stem cells (ASCs), human umbilical vein endothelial cells (HUVECs), immortalized human keratinocyte (HaCaT) cells and human monocytic leukemia cells (THP-1) were used in this study to show that the SC-CO 2 -treated ECM coating can be potentially used for various biomedical applications. The SC-CO 2 -treated ECM material showed improved cell-material interactions for all cell types tested. In addition, in vitro scratch wound assay using HaCaT cells showed that the presence of SC-CO 2 -treated ECM material enhanced keratinocyte migration whilst the in vitro cellular studies using THP-1-derived macrophages showed that the SC-CO 2 -treated ECM material did not evoke pro-inflammatory responses from the THP-1-derived macrophages. Overall, this study shows the efficacy of SC-CO 2 method for delipidation and decellularization of adipose tissue whilst retaining its ECM and its subsequent utilization as a bioactive surface coating material for soft tissue engineering, angiogenesis and wound healing applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Subpopulations of Ig-secreting cells induced by peroxidase immunization: discrimination according to antibody storage and secretion.

PubMed Central

Bernard, J; Jeannesson, P; Thiernesse, N; Zagury, D; Ternynck, T; Avrameas, S

1979-01-01

Mice were injected in their hind footpads with peroxidase (PO) emulsified in Freund's complete adjuvant. The development of cells secreting anti-peroxidase antibody (Ab) and cells secreting immunoglobulins (Ig) were detected in the draining popliteal lymph nodes in the subsequent 35 days, using local haemolysis plaque assay with sheep red cell blood cells coated with either PO or anti-mouse Ig antibody. Plaque-forming cells (PFC) were isolated from the centre of plaques by micromanipulation and after appropriate treatment, were examined by electron microscopy for their intracellular Ab content and in corporation of [3H]-thymidine. Four subpopulations of Ig secreting cells were distinguished: (1) cells secreting Ig without Ab function and not containing intracellular Ab detectable between days 5 and 20; (2) cells secreting Ig without Ab function but containing Ab appearing on day 6 and present throughout the immune response; (3) cells secreting Ab and containing Ab; (4) cells secreting Ab, but without detectable intracellular Ab. These last subpopulations appeared on day 7 and were found in all subsequent assays. The analysis of the kinetics of these subpopulations suggest that cells secreting Ig without Ab function might be precursors of Ab secreting cells. Images Figure 2a Figure 2b Figure 4 PMID:374259

Molecular Processes that Drive Cigarette Smoke–Induced Epithelial Cell Fate of the Lung

PubMed Central

Nyunoya, Toru; Mebratu, Yohannes; Contreras, Amelia; Delgado, Monica; Chand, Hitendra S.

2014-01-01

Cigarette smoke contains numerous chemical compounds, including abundant reactive oxygen/nitrogen species and aldehydes, and many other carcinogens. Long-term cigarette smoking significantly increases the risk of various lung diseases, including chronic obstructive pulmonary disease and lung cancer, and contributes to premature death. Many in vitro and in vivo studies have elucidated mechanisms involved in cigarette smoke–induced inflammation, DNA damage, and autophagy, and the subsequent cell fates, including cell death, cellular senescence, and transformation. In this Translational Review, we summarize the known pathways underlying these processes in airway epithelial cells to help reveal future challenges and describe possible directions of research that could lead to better management and treatment of these diseases. PMID:24111585

Development of LC/MS/MS, high-throughput enzymatic and cellular assays for the characterization of compounds that inhibit kynurenine monooxygenase (KMO).

PubMed

Winkler, Dirk; Beconi, Maria; Toledo-Sherman, Leticia M; Prime, Michael; Ebneth, Andreas; Dominguez, Celia; Muñoz-Sanjuan, Ignacio

2013-09-01

Kynurenine monooxygenase (KMO) catalyzes the conversion of kynurenine to 3-hydroxykynurenine. Modulation of KMO activity has been implicated in several neurodegenerative diseases, including Huntington disease. Our goal is to develop potent and selective small-molecule KMO inhibitors with suitable pharmacokinetic characteristics for in vivo proof-of-concept studies and subsequent clinical development. We developed a comprehensive panel of biochemical and cell-based assays that use liquid chromatography/tandem mass spectrometry to quantify unlabeled kynurenine and 3-hydroxykynurenine. We describe assays to measure KMO inhibition in cell and tissue extracts, as well as cellular assays including heterologous cell lines and primary rat microglia and human peripheral blood mononuclear cells.

Mesenchymal stem cells cancel azoxymethane-induced tumor initiation.

PubMed

Nasuno, Masanao; Arimura, Yoshiaki; Nagaishi, Kanna; Isshiki, Hiroyuki; Onodera, Kei; Nakagaki, Suguru; Watanabe, Shuhei; Idogawa, Masashi; Yamashita, Kentaro; Naishiro, Yasuyoshi; Adachi, Yasushi; Suzuki, Hiromu; Fujimiya, Mineko; Imai, Kohzoh; Shinomura, Yasuhisa

2014-04-01

The role of mesenchymal stem cells (MSCs) in tumorigenesis remains controversial. Therefore, our goal was to determine whether exogenous MSCs possess intrinsic antineoplastic or proneoplastic properties in azoxymethane (AOM)-induced carcinogenesis. Three in vivo models were studied: an AOM/dextran sulfate sodium colitis-associated carcinoma model, an aberrant crypt foci model, and a model to assess the acute apoptotic response of a genotoxic carcinogen (AARGC). We also performed in vitro coculture experiments. As a result, we found that MSCs partially canceled AOM-induced tumor initiation but not tumor promotion. Moreover, MSCs inhibited the AARGC in colonic epithelial cells because of the removal of O(6)-methylguanine (O(6) MeG) adducts through O(6) MeG-DNA methyltransferase activation. Furthermore, MSCs broadly affected the cell-cycle machinery, potentially leading to G1 arrest in vivo. Coculture of IEC-6 rat intestinal cells with MSCs not only arrested the cell cycle at the G1 phase, but also induced apoptosis. The anti-carcinogenetic properties of MSCs in vitro required transforming growth factor (TGF)-β signaling because such properties were completely abrogated by absorption of TGF-β under indirect coculture conditions. MSCs inhibited AOM-induced tumor initiation by preventing the initiating cells from sustaining DNA insults and subsequently inducing G1 arrest in the initiated cells that escaped from the AARGC. Furthermore, tumor initiation perturbed by MSCs might potentially dysregulate WNT and TGF-β-Smad signaling pathways in subsequent tumorigenesis. Obtaining a better understanding of MSC functions in colon carcinogenesis is essential before commencing the broader clinical application of promising MSC-based therapies for cancer-prone patients with inflammatory bowel disease. © AlphaMed Press.

The Mast Cell Degranulator Compound 48/80 Directly Activates Neurons

PubMed Central

Schemann, Michael; Kugler, Eva Maria; Buhner, Sabine; Eastwood, Christopher; Donovan, Jemma; Jiang, Wen; Grundy, David

2012-01-01

Background Compound 48/80 is widely used in animal and tissue models as a “selective” mast cell activator. With this study we demonstrate that compound 48/80 also directly activates enteric neurons and visceral afferents. Methodology/Principal Findings We used in vivo recordings from extrinsic intestinal afferents together with Ca++ imaging from primary cultures of DRG and nodose neurons. Enteric neuronal activation was examined by Ca++ and voltage sensitive dye imaging in isolated gut preparations and primary cultures of enteric neurons. Intraluminal application of compound 48/80 evoked marked afferent firing which desensitized on subsequent administration. In egg albumen-sensitized animals, intraluminal antigen evoked a similar pattern of afferent activation which also desensitized on subsequent exposure to antigen. In cross-desensitization experiments prior administration of compound 48/80 failed to influence the mast cell mediated response. Application of 1 and 10 µg/ml compound 48/80 evoked spike discharge and Ca++ transients in enteric neurons. The same nerve activating effect was observed in primary cultures of DRG and nodose ganglion cells. Enteric neuron cultures were devoid of mast cells confirmed by negative staining for c-kit or toluidine blue. In addition, in cultured enteric neurons the excitatory action of compound 48/80 was preserved in the presence of histamine H1 and H2 antagonists. The mast cell stabilizer cromolyn attenuated compound 48/80 and nicotine evoked Ca++ transients in mast cell-free enteric neuron cultures. Conclusions/Significance The results showed direct excitatory action of compound 48/80 on enteric neurons and visceral afferents. Therefore, functional changes measured in tissue or animal models may involve a mast cell independent effect of compound 48/80 and cromolyn. PMID:23272218

Decreased survival of prostate cancer cells in vitro by combined treatment of heat and an antioxidant inhibitor diethyldithiocarbamate (DDC).

PubMed

Moriyama-Gonda, Nobuko; Igawa, Mikio; Shiina, Hiroaki; Urakami, Shinji; Terashima, Masaharu

2003-11-01

The aim of this study was to examine a modulation of thermotolerance by treatment with combination of heat and the antioxidant inhibitor diethyldithiocarbamate (DDC) of the PC-3 prostate cancer cells. To determine thermotolerance, cells were heated once or twice. Two 1 h exposures at 43 degrees C, with a recovery period in between, revealed better survival/recovery of cells after the second exposure than after the first (fig. 1A + 1B). Additional experiments were performed, heating cells twice (fig. 1B + 1C). First, cells were heated at 43 degrees C for 1 h and, after various recovery times (intervals) at 37 degree C, subsequently reheated at 44 degrees C for 1 h. To ensure effective cell killing, efficiency of the combined treatments of 1 mM DDC and heating at 43 or 44 degrees C for 1 h was estimated by measuring cell survival, reactive oxygen species (ROS) generation, superoxide dismutase (SOD) activity and heat shock protein 70 (hsp 70) expression. To obtain a more effective method for subsequent heat exposure, cells were heated twice after a 24 h interval in the presence or absence of 1 mM DDC. ROS generation and SOD activity immediately increased correlating with duration of heating, but their levels gently decreased with time after discontinuation of heating. On the other hand, hsp 70 levels slowly increased, also correlating with duration of heating but continued to increase with time after discontinuation of heating for a certain period. DDC administration coupled with heating at 43 or 44 degrees C significantly decreased cell survival compared to heating alone (p < 0.05). Furthermore, significant decreases in numbers of viable cells were observed for cells after the first heat exposure when combined with DDC as compared to heat alone at 43 and 44 degrees C (p < 0.05). These findings suggest that heat combined with DDC could have potential benefits in the treatment of prostate cancer.

Ethylene Upregulates Auxin Biosynthesis in Arabidopsis Seedlings to Enhance Inhibition of Root Cell Elongation[W

PubMed Central

Swarup, Ranjan; Perry, Paula; Hagenbeek, Dik; Van Der Straeten, Dominique; Beemster, Gerrit T.S.; Sandberg, Göran; Bhalerao, Rishikesh; Ljung, Karin; Bennett, Malcolm J.

2007-01-01

Ethylene represents an important regulatory signal for root development. Genetic studies in Arabidopsis thaliana have demonstrated that ethylene inhibition of root growth involves another hormone signal, auxin. This study investigated why auxin was required by ethylene to regulate root growth. We initially observed that ethylene positively controls auxin biosynthesis in the root apex. We subsequently demonstrated that ethylene-regulated root growth is dependent on (1) the transport of auxin from the root apex via the lateral root cap and (2) auxin responses occurring in multiple elongation zone tissues. Detailed growth studies revealed that the ability of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid to inhibit root cell elongation was significantly enhanced in the presence of auxin. We conclude that by upregulating auxin biosynthesis, ethylene facilitates its ability to inhibit root cell expansion. PMID:17630275

From single cells to tissue architecture-a bottom-up approach to modelling the spatio-temporal organisation of complex multi-cellular systems.

PubMed

Galle, J; Hoffmann, M; Aust, G

2009-01-01

Collective phenomena in multi-cellular assemblies can be approached on different levels of complexity. Here, we discuss a number of mathematical models which consider the dynamics of each individual cell, so-called agent-based or individual-based models (IBMs). As a special feature, these models allow to account for intracellular decision processes which are triggered by biomechanical cell-cell or cell-matrix interactions. We discuss their impact on the growth and homeostasis of multi-cellular systems as simulated by lattice-free models. Our results demonstrate that cell polarisation subsequent to cell-cell contact formation can be a source of stability in epithelial monolayers. Stroma contact-dependent regulation of tumour cell proliferation and migration is shown to result in invasion dynamics in accordance with the migrating cancer stem cell hypothesis. However, we demonstrate that different regulation mechanisms can equally well comply with present experimental results. Thus, we suggest a panel of experimental studies for the in-depth validation of the model assumptions.

Calculation of 3D genome structures for comparison of chromosome conformation capture experiments with microscopy: An evaluation of single-cell Hi-C protocols.

PubMed

Lando, David; Stevens, Tim J; Basu, Srinjan; Laue, Ernest D

2018-01-01

Single-cell chromosome conformation capture approaches are revealing the extent of cell-to-cell variability in the organization and packaging of genomes. These single-cell methods, unlike their multi-cell counterparts, allow straightforward computation of realistic chromosome conformations that may be compared and combined with other, independent, techniques to study 3D structure. Here we discuss how single-cell Hi-C and subsequent 3D genome structure determination allows comparison with data from microscopy. We then carry out a systematic evaluation of recently published single-cell Hi-C datasets to establish a computational approach for the evaluation of single-cell Hi-C protocols. We show that the calculation of genome structures provides a useful tool for assessing the quality of single-cell Hi-C data because it requires a self-consistent network of interactions, relating to the underlying 3D conformation, with few errors, as well as sufficient longer-range cis- and trans-chromosomal contacts.

Spiral actin-polymerization waves can generate amoeboidal cell crawling

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

Dreher, A.; Aranson, I. S.; Kruse, K.

2014-05-01

Amoeboidal cell crawling on solid substrates is characterized by protrusions that seemingly appear randomly along the cell periphery and drive the cell forward. For many cell types, it is known that the protrusions result from polymerization of the actin cytoskeleton. However, little is known about how the formation of protrusions is triggered and whether the appearance of subsequent protrusions is coordinated. Recently, the spontaneous formation of actin-polymerization waves was observed. These waves have been proposed to orchestrate the cytoskeletal dynamics during cell crawling. Here, we study the impact of cytoskeletal polymerization waves on cell migration using a phase-field approach. Inmore » addition to directionally moving cells, we find states reminiscent of amoeboidal cell crawling. In this framework, new protrusions are seen to emerge from a nucleation process, generating spiral actin waves in the cell interior. Nucleation of new spirals does not require noise, but occurs in a state that is apparently displaying spatio-temporal chaos.« less

A phase I clinical study of immunotherapy for advanced colorectal cancers using carcinoembryonic antigen-pulsed dendritic cells mixed with tetanus toxoid and subsequent IL-2 treatment.

PubMed

Liu, Ko-Jiunn; Chao, Tsu-Yi; Chang, Jang-Yang; Cheng, Ann-Lii; Ch'ang, Hui-Ju; Kao, Woei-Yau; Wu, Yu-Chen; Yu, Wei-Lan; Chung, Tsai-Rong; Whang-Peng, Jacqueline

2016-08-24

To better evaluate and improve the efficacy of dendritic cell (DC)-based cancer immunotherapy, we conducted a clinical study of patients with advanced colorectal cancer using carcinoembryonic antigen (CEA)-pulsed DCs mixed with tetanus toxoid and subsequent interleukin-2 treatment. The tetanus toxoid in the vaccine preparation serves as an adjuvant and provides a non-tumor specific immune response to enhance vaccine efficacy. The aims of this study were to (1) evaluate the toxicity of this treatment, (2) observe the clinical responses of vaccinated patients, and (3) investigate the immune responses of patients against CEA before and after treatment. Twelve patients were recruited and treated in this phase I clinical study. These patients all had metastatic colorectal cancer and failed standard chemotherapy. We first subcutaneously immunized patients with metastatic colorectal cancer with 1 × 10(6) CEA-pulsed DCs mixed with tetanus toxoid as an adjuvant. Patients received 3 successive injections with 1 × 10(6) CEA-pulsed DCs alone. Low-dose interleukin-2 was administered subcutaneously following the final DC vaccination to boost the growth of T cells. Patients were evaluated for adverse event and clinical status. Blood samples collected before, during, and after treatment were analyzed for T cell proliferation responses against CEA. No severe treatment-related side effects or toxicity was observed in patients who received the regular 4 DC vaccine injections. Two patients had stable disease and 10 patients showed disease progression. A statistically significant increase in proliferation against CEA by T cells collected after vaccination was observed in 2 of 9 patients. The results of this study indicate that it is feasible and safe to treat colorectal cancer patients using this protocol. An increase in the anti-CEA immune response and a clinical benefit was observed in a small fraction of patients. This treatment protocol should be further evaluated in additional colorectal cancer patients with modifications to enhance T cell responses. ClinicalTrials.gov (identifier NCT00154713 ), September 8, 2005.

Phosphatidylserine translocation to the mitochondrion is an ATP-dependent process in permeabilized animal cells

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

Voelker, D.R.

1989-12-01

Chinese hamster ovary (CHO-K1) cells were pulse labeled with ({sup 3}H)serine, and the synthesis of phosphatidyl({sup 3}H)ethanolamine from phosphatidyl({sup 3}H)serine during the subsequent chase was used as a measure of lipid translocation to the mitochondria. When the CHO-K1 cells were pulse labeled and subsequently permeabilized with 50 {mu}g of saponin per ml, there was no significant turnover of nascent phosphatidyl({sup 3}H)serine to form phosphatidyl({sup 3}H)ethanolamine during an ensuring chase. Supplementation of the permeabilized cells with 2 mM ATP resulted in significant phosphatidyl({sup 3}H)ethanolamine synthesis (83% of that found in intact cells) from phosphatidyl({sup 3}H)serine during a subsequent 2-hr chase. Phosphatidyl({supmore » 3}H)ethanolamine synthesis essentially ceased after 2 hr in the permeabilized cells. The translocation-dependent synthesis of phosphatidyl({sup 3}H)ethanolamine was a saturable process with respect to ATP concentration in permeabilized cells. The conversion of phosphatidyl({sup 3}H)serine to phosphatidyl({sup 3}H)ethanolamine did not occur in saponin-treated cultures supplemented with 2 mM AMP, 2 mM 5{prime}-adenylyl imidodiphosphate, or apyrase plus 2 mM ATP. ATP was the most effective nucleotide, but the addition of GTP, CTP, UTP, and ADP also supported the translocation-dependent synthesis of phosphatidyl({sup 3}H)ethanolamine albeit to a lesser extent. These data provide evidence that the interorganelle translocation of phosphatidylserine requires ATP and is largely independent of soluble cytosolic proteins.« less

The effect of differentiation agents on inflammatory and oxidative responses of the human neuroblastoma cell line SK-N-SH.

PubMed

Niewiarowska-Sendo, Anna; Patrzalek, Katarzyna; Kozik, Andrzej; Guevara-Lora, Ibeth

2015-01-01

Obtaining a suitable experimental cellular model is a major problem for neuroscience studies. Neuroblastoma cell lines have been often applied in studies related to pathological disorders of nervous system. However, in the search for an ideal model, these cells must be differentiated to cancel their tumor character. The subsequent reactions that are caused by differentiation are not always indifferent to the same model. We evaluated the effect of two well known substances, used for SH-N-SK cell line differentiation, retinoic acid (RA) and phorbol-12-myristate-13-acetate (PMA), on the induction of pro-inflammatory and pro-oxidative reactions in these cells. Cells differentiated with PMA were able to produce significantly higher amounts of pro-inflammatory cytokines whereas the release of nitric oxide radicals was similar to that in undifferentiated cells. On the contrary, in RA-differentiated cells no significant changes in cytokine production were observed and the nitric oxide release was decreased. Additionally, the RA-differentiated neuronal model was more sensible to lipopolysaccharide stimulation, producing pro-inflammatory cytokines abundantly. These results suggest that RA-differentiated SH-N-SK cells provide a more suitable experimental model for the study of molecular and cellular mechanisms of the inflammation and oxidative stress in neuronal cells.

CCR 20th anniversary commentary: Radioactive Drones for B-cell lymphoma.

PubMed

Knox, Susan J; Levy, Ronald

2015-02-01

In a study published in the March 1, 1996, issue of Clinical Cancer Research, Knox and colleagues (1) demonstrated the safety and efficacy of Yttirium-90 ((90)Y)-anti-CD20 monoclonal antibody therapy, as well as the benefit of preinfusion of unlabeled antibody on radiolabeled antibody biodistribution. Subsequent clinical trials with this radiolabeled antibody led to regulatory approval of this treatment for B-cell lymphoma. See related article by Knox et al., Clin Cancer Res 1996;2(3) Mar 1996; 457-70. ©2015 American Association for Cancer Research.

Manipulation of mammalian cells using a single-fiber optical microbeam

PubMed Central

Mohanty, Samarendra K.; Mohanty, Khyati S.; Berns, Michael W.

2014-01-01

The short working distance of microscope objectives has severely restricted the application of optical micromanipulation techniques at larger depths. We show the first use of fiber-optic tweezers toward controlled guidance of neuronal growth cones and stretching of neurons. Further, by mode locking, the fiber-optic tweezers beam was converted to fiber-optic scissors, enabling dissection of neuronal processes and thus allowing study of the subsequent response of neurons to localized injury. At high average powers, lysis of a three-dimensionally trapped cell was accomplished. PMID:19021429

Anaerobic choline metabolism in microcompartments promotes growth and swarming of P roteus mirabilis

PubMed Central

Jameson, Eleanor; Fu, Tiantian; Brown, Ian R.; Paszkiewicz, Konrad; Purdy, Kevin J.

2015-01-01

Summary Gammaproteobacteria are important gut microbes but only persist at low levels in the healthy gut. The ecology of G ammaproteobacteria in the gut environment is poorly understood. Here, we demonstrate that choline is an important growth substrate for representatives of G ammaproteobacteria. Using P roteus mirabilis as a model, we investigate the role of choline metabolism and demonstrate that the cut C gene, encoding a choline‐trimethylamine lyase, is essential for choline degradation to trimethylamine by targeted mutagenesis of cut C and subsequent complementation experiments. P roteus mirabilis can rapidly utilize choline to enhance growth rate and cell yield in broth culture. Importantly, choline also enhances swarming‐associated colony expansion of P . mirabilis under anaerobic conditions on a solid surface. Comparative transcriptomics demonstrated that choline not only induces choline‐trimethylamine lyase but also genes encoding shell proteins for the formation of bacterial microcompartments. Subsequent analyses by transmission electron microscopy confirmed the presence of such novel microcompartments in cells cultivated in liquid broth and hyper‐flagellated swarmer cells from solid medium. Together, our study reveals choline metabolism as an adaptation strategy for P . mirabilis and contributes to better understand the ecology of this bacterium in health and disease. PMID:26404097

Endothelial-astrocytic interactions in acute liver failure.

PubMed

Jayakumar, A R; Norenberg, M D

2013-06-01

Brain edema and the subsequent increase in intracranial pressure are major neurological complications of acute liver failure (ALF), and swelling of astrocytes (cytotoxic brain edema) is the most prominent neuropathological abnormality in ALF. Recent studies, however, have suggested the co-existence of cytotoxic and vasogenic mechanisms in the brain edema associated with ALF. This review 1) summarizes the nature of the brain edema in humans and experimental animals with ALF; 2) reviews in vitro studies supporting the presence of cytotoxic brain edema (cell swelling in cultured astrocytes); and 3) documents the role of brain endothelial cells in the development of astrocyte swelling/brain edema in ALF.

Synchronized mammalian cell culture: part I--a physical strategy for synchronized cultivation under physiological conditions.

PubMed

Barradas, Oscar Platas; Jandt, Uwe; Becker, Max; Bahnemann, Janina; Pörtner, Ralf; Zeng, An-Ping

2015-01-01

Conventional analysis and optimization procedures of mammalian cell culture processes mostly treat the culture as a homogeneous population. Hence, the focus is on cell physiology and metabolism, cell line development, and process control strategy. Impact on cultivations caused by potential variations in cellular properties between different subpopulations, however, has not yet been evaluated systematically. One main cause for the formation of such subpopulations is the progress of all cells through the cell cycle. The interaction of potential cell cycle specific variations in the cell behavior with large-scale process conditions can be optimally determined by means of (partially) synchronized cultivations, with subsequent population resolved model analysis. Therefore, it is desirable to synchronize a culture with minimal perturbation, which is possible with different yield and quality using physical selection methods, but not with frequently used chemical or whole-culture methods. Conventional nonsynchronizing methods with subsequent cell-specific, for example, flow cytometric analysis, can only resolve cell-limited effects of the cell cycle. In this work, we demonstrate countercurrent-flow centrifugal elutriation as a useful physical method to enrich mammalian cell populations within different phases of a cell cycle, which can be further cultivated for synchronized growth in bioreactors under physiological conditions. The presented combined approach contrasts with other physical selection methods especially with respect to the achievable yield, which makes it suitable for bioreactor scale cultivations. As shown with two industrial cell lines (CHO-K1 and human AGE1.HN), synchronous inocula can be obtained with overall synchrony degrees of up to 82% in the G1 phase, 53% in the S phase and 60% in the G2/M phase, with enrichment factors (Ysync) of 1.71, 1.79, and 4.24 respectively. Cells are able to grow with synchrony in bioreactors over several cell cycles. This strategy, combined with population-resolved model analysis and parameter extraction as described in the accompanying paper, offers new possibilities for studies of cell lines and processes at levels of cell cycle and population under physiological conditions. © 2014 American Institute of Chemical Engineers.

The effect of in vivo and in vitro irradiation (25 Gy) on the subsequent in vitro growth of satellite cells

NASA Technical Reports Server (NTRS)

Mozdziak, P. E.; Schultz, E.; Cassens, R. G.

1996-01-01

The effect of in vivo and in vitro irradiation on subsequent satellite cell growth, in vitro, was investigated to ascertain the ability of a 25 Gy dose to inhibit satellite cell proliferation. Satellite cells were isolated from the left (irradiated) and right (non-irradiated) Pectoralis thoracicus of two-week-old tom turkeys 16 h (n=3) and seven weeks (n=2) after the left Pectoralis thoracicus had been irradiated (25 Gy). Satellite cells isolated from the irradiated and non-irradiated muscles exhibited similar (P>0.10) in vitro proliferation indicating that a population of satellite cells survived an in vivo dose of 25 Gy. In additional experiments, satellite cell cultures derived from tom turkey Pectoralis thoracicus were irradiated (25 Gy) in vitro. The number of satellite cells did not (P>0.05) increase in irradiated cultures for 134 h following irradiation, while satellite cells in non-irradiated cultures proliferated (P<0.05) over this time. At later time periods, satellite cell number increased (P<0.05) in irradiated cultures indicating that a population of satellite cells survived irradiation. The results of these in vitro experiments suggest that a 25 Gy dose of irradiation does not abolish satellite cell divisions in the turkey Pectoralis thoracicus.

The Effect of Gravity Fields on Cellular Gene Expression

NASA Technical Reports Server (NTRS)

Hughes-Fulford, Millie

1999-01-01

Early theoretical analysis predicted that microgravity effects on the isolated cell would be minuscule at the subcellular level; however, these speculations have not proven true in the real world. Astronauts experience a significant bone and muscle loss in as little as 2 weeks of spaceflight and changes are seen at the cellular level soon after exposure to microgravity. Changes in biological systems may be primarily due to the lack of gravity and the resulting loss of mechanical stress on tissues and cells. Recent ground and flight studies examining the effects of gravity or mechanical stress on cells demonstrate marked changes in gene expression when relatively small changes in mechanical forces or gravity fields were made. Several immediate early genes (IEG) like c-fos and c-myc are induced by mechanical stimulation within minutes. In contrast, several investigators report that the absence of mechanical forces during space flight result in decreased sera response element (SRE) activity and attenuation of expression of IEGs such as c-fos, c-jun and cox-2 mRNAs. Clearly, these early changes in gene expression may have long term consequences on mechanically sensitive cells. In our early studies on STS-56, we reported four major changes in the osteoblast; 1) prostaglandin synthesis in flight, 2) changes in cellular morphology, 3) altered actin cytoskeleton and 4) reduced osteoblast growth after four days exposure to microgravity. Initially, it was believed that changes in fibronectin (FN) RNA, FN protein synthesis or subsequent FN matrix formation might account for the changes in cytoskeleton and/ or reduction of growth. However our recent studies on Biorack (STS-76, STS-81 and STS-84), using ground and in-flight 1-G controls, demonstrated that fibronectin synthesis and matrix formation were normal in microgravity. In addition, in our most recent Biorack paper, our laboratory has documented that relative protein synthesis and mRNA synthesis are not changed after 24 hours exposure to microgravity. We did, however, find significant changes in osteoblast gene expression of IEGs, c-fos and cox-2 in microgravity exposure as compared to ground and in-flight 1-G controls. Subsequent ground studies suggest that the molecular mechanism underlying these changes may involve prostaglandin c-AMP receptors (EPs) and/or subsequent alteration of intracellular signaling in the absence of gravity.

Cellular mechanism of resistance of human colorectal adenocarcinoma cells against apoptosis-induction by Russell's Viper venom L-amino acid oxidase (Rusvinoxidase).

PubMed

Mukherjee, Ashis K; Saviola, Anthony J; Mackessy, Stephen P

2018-04-24

The present study highlights the cellular mechanism of resistance in human adenocarcinoma (Colo-205) cells against apoptosis induction by Rusvinoxidase, an L-amino acid oxidase purified from Russell's Viper venom (RVV). The significantly lower cytotoxicity as well as apoptotic activity of Rusvinoxidase towards Colo-205 cells (compared to MCF-7 breast cancer cells) is correlated with lower depletion of cellular glutathione content and increased down-regulation of catalase activity of Colo-205 cells following Rusvinoxidase treatment. Exposure to Rusvinoxidase subsequently diminished reactive oxygen species (ROS) production and failed to impair mitochondrial membrane potential, resulting in apoptosis induction resistance in Colo-205 cells. Further, higher expression levels of caspase 8, compared to caspase 9, indicate that Rusvinoxidase preferentially triggers the extrinsic pathway of apoptosis in Colo-205 cells. A time-dependent lower ratio of the relative expression of Bax and Bcl-xL (pro- and anti-apoptotic proteins) in Colo-205 cells, compared to our previous study on MCF-7 cells, unambiguously supports a higher cellular resistance mechanism in Colo-205 cells against Rusvinoxidase-induced apoptosis. Copyright © 2018. Published by Elsevier B.V.

Doxorubicin induces ZAKα overexpression with a subsequent enhancement of apoptosis and attenuation of survivability in human osteosarcoma cells.

PubMed

Fu, Chien-Yao; Tseng, Yan-Shen; Chen, Ming-Cheng; Hsu, Hsi-Hsien; Yang, Jaw-Ji; Tu, Chuan-Chou; Lin, Yueh-Min; Viswanadha, Vijaya Padma; Kuo, Wei-Wen; Huang, Chih-Yang

2018-02-01

Human osteosarcoma (OS) is a malignant cancer of the bone. It exhibits a characteristic malignant osteoblastic transformation and produces a diseased osteoid. A previous study demonstrated that doxorubicin (DOX) chemotherapy decreases human OS cell proliferation and might enhance the relative RNA expression of ZAK. However, the impact of ZAKα overexpression on the OS cell proliferation that is inhibited by DOX and the molecular mechanism underlying this effect are not yet known. ZAK is a protein kinase of the MAPKKK family and functions to promote apoptosis. In our study, we found that ZAKα overexpression induced an apoptotic effect in human OS cells. Treatment of human OS cells with DOX enhanced ZAKα expression and decreased cancer cell viability while increasing apoptosis of human OS cells. In the meantime, suppression of ZAKα expression using shRNA and inhibitor D1771 both suppressed the DOX therapeutic effect. These findings reveal a novel molecular mechanism underlying the DOX effect on human OS cells. Taken together, our findings demonstrate that ZAKα enhances the apoptotic effect and decreases cell viability in DOX-treated human OS cells. © 2017 Wiley Periodicals, Inc.

Early cellular evolution.

NASA Technical Reports Server (NTRS)

Margulis, L.

1972-01-01

Study of the evolutionary developments that occurred subsequent to the origin of ancestral cells. Microbial physiology and ecology are potential sharp tools for shaping concepts of microbial evolution. Some popular unjustified assumptions are discussed. It is considered that certain principles derived mainly from the advances of molecular biology can be used to order the natural groups (genera) of extant prokaryotes and their patterns phylogenetically.

Serum ghrelin is inversely associated with risk of subsequent oesophageal squamous cell carcinoma

PubMed Central

Murphy, Gwen; Kamangar, Farin; Albanes, Demetrius; Stanczyk, Frank Z.; Weinstein, Stephanie J.; Taylor, Philip R.; Virtamo, Jarmo; Abnet, Christian C.; Dawsey, Sanford M.; Freedman, Neal D.

2012-01-01

Background Oesophageal cancers rank as the eighth most common cancer and the sixth most common cause of cancer death, worldwide. Gastric atrophy, as determined by a low serum pepsinogen I/II ratio, may be associated with an increased risk of oesophageal squamous cell carcinoma (OSCC). Ghrelin, a hormone which, like pepsinogen, is produced in the fundic glands of the stomach, may be a sensitive and specific marker of gastric atrophy, but its association with OSCC is not known. Methods To examine the relationship between baseline serum ghrelin concentration and subsequent risk of OSCC, we conducted a nested case-control study within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study. 82 cases of OSCC were matched (1:1) by age and date of blood draw to controls from the ATBC study. Serum ghrelin was measured by radioimmunoassay. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using conditional logistic regression with adjustment for potential confounders. Results For those individuals in the lowest quartile of serum ghrelin, compared to those in the highest, the multivariate odds ratio of subsequent OSCC was 6.83 (95% CI: 1.46, 31.84). These associations were dose dependent (P for trend = 0.005 for both), and independent of the effects of low pepsinogen I/II ratio (a marker of gastric fundic atrophy) and Helicobacter pylori infection. The significance of these associations remained even for individuals developing OSCC up to 10 years after baseline ghrelin measurement, though they become attenuated after 10 years. Conclusion Lower baseline concentrations of serum ghrelin were associated with an increase in risk of OSCC. Further studies are needed to confirm this finding in other populations and to explore the role of ghrelin in the aetiology of OSCC. PMID:22180062

Temperature Treatment of Highly Porous Zirconium-Containing Metal-Organic Frameworks Extends Drug Delivery Release.

PubMed

Teplensky, Michelle H; Fantham, Marcus; Li, Peng; Wang, Timothy C; Mehta, Joshua P; Young, Laurence J; Moghadam, Peyman Z; Hupp, Joseph T; Farha, Omar K; Kaminski, Clemens F; Fairen-Jimenez, David

2017-06-07

Utilizing metal-organic frameworks (MOFs) as a biological carrier can lower the amount of the active pharmaceutical ingredient (API) required in cancer treatments to provide a more efficacious therapy. In this work, we have developed a temperature treatment process for delaying the release of a model drug compound from the pores of NU-1000 and NU-901, while taking care to utilize these MOFs' large pore volume and size to achieve exceptional model drug loading percentages over 35 wt %. Video-rate super-resolution microscopy reveals movement of MOF particles when located outside of the cell boundary, and their subsequent immobilization when taken up by the cell. Through the use of optical sectioning structured illumination microscopy (SIM), we have captured high-resolution 3D images showing MOF uptake by HeLa cells over a 24 h period. We found that addition of a model drug compound into the MOF and the subsequent temperature treatment process does not affect the rate of MOF uptake by the cell. Endocytosis analysis revealed that MOFs are internalized by active transport and that inhibiting the caveolae-mediated pathway significantly reduced cellular uptake of MOFs. Encapsulation of an anticancer therapeutic, alpha-cyano-4-hydroxycinnamic acid (α-CHC), and subsequent temperature treatment produced loadings of up to 81 wt % and demonstrated efficacy at killing cells beyond the burst release effect.

"Isogaba Maware": quality control of genome DNA by checkpoints.

PubMed

Kitazono, A; Matsumoto, T

1998-05-01

Checkpoints maintain the interdependency of cell cycle events by permitting the onset of an event only after the completion of the preceding event. The DNA replication checkpoint induces a cell cycle arrest until the completion of the DNA replication. Similarly, the DNA damage checkpoint arrests cell cycle progression if DNA repair is incomplete. A number of genes that play a role in the two checkpoints have been identified through genetic studies in yeasts, and their homologues have been found in fly, mouse, and human. They form signaling cascades activated by a DNA replication block or DNA damage and subsequently generate the negative constraints on cell cycle regulators. The failure of these signaling cascades results in producing offspring that carry mutations or that lack a portion of the genome. In humans, defects in the checkpoints are often associated with cancer-prone diseases. Focusing mainly on the studies in budding and fission yeasts, we summarize the recent progress.

Characterization of ligand binding and processing by gastrin-releasing peptide receptors in a small-cell lung cancer cell line.

PubMed Central

Cardona, C; Bleehen, N M; Reeve, J G

1992-01-01

The ligand-binding properties of the gastrin-releasing peptide (GRP) receptor and the cellular processing of GRP have been studied in the small-cell lung cancer (SCLC) cell line COR-L42. Scatchard analysis of GRP receptor expression indicated a single class of high-affinity receptors (Kd 1.5 nM) and approx. 6700 receptors/cell. GRP bound to its receptor with a Ki of 2.4 nM. The bombesin-related peptides neuromedin B (NMB) and phyllolitorin also bound to GRP receptors with Ki values of 22.7 and 59.1 nM respectively. Binding of 125I-GRP to COR-L42 cells increased rapidly at 37 degrees, achieved a maximum at 10 min and declined rapidly thereafter. At 4 degrees C, maximum binding was achieved at 30 min and the subsequent decline in cell-associated radioactivity was slower than that seen at 37 degrees C. Acid/salt extraction, to separate surface-bound ligand from internalized GRP, indicated that after receptor binding 125I-GRP was rapidly internalized. To determine the pathway of 125I-GRP degradation, binding studies were carried out with the lysosomotropic agent chloroquine (5 mM), and with phosphoramidon (10 microM), an inhibitor of the membrane-bound enzyme (EC 3.4.24.11). Both agents markedly inhibited the degradation of GRP, indicating that this process involves a lysosomal pathway and a phosphoramidon-sensitive pathway, possibly involving the EC 3.4.24.11 enzyme. GRP receptor down-regulation was observed following a 10 min exposure to 100 nM-GRP. With longer pretreatment times the number of binding sites recovered to 80% of control values. Treatment with 5 mM-chloroquine plus GRP or cycloheximide (10 micrograms/ml) plus GRP demonstrated that the majority of GRP receptors are recycled. NMB and phyllolitorin pretreatment did not influence the subsequent binding of 125I-GRP, suggesting that these peptides do not down-regulate GRP receptors. PMID:1310003

Simultaneous determination of the heat and the quantity of vapor sorption using a novel microcalorimetric method.

PubMed

Lehto, V P; Laine, E

2000-06-01

In this study, instrumentation for measuring vapor sorption enthalpies and sorption uptakes simultaneously with an isothermal microcalorimeter is introduced. Various pharmaceutical model substances undergoing phase transitions when exposed to humid conditions (25 degrees C), were employed to evaluate the usefulness and sensitivity of the constructed experimental method. The sample is placed in the sample vessel of a RH cell and the moisture content of the air flow is controlled. From the RH cell the air flow is conducted into a subsequent perfusion cell in which a saturated salt solution has been loaded. The RH cell and perfusion cells are positioned in the sample sides of two twin calorimetric units. Depending on the moisture content in the outlet flow leaving the preceding RH cell, the heat flow signal from the subsequent perfusion cell will vary. By means of blank measurement with identical settings, the rate of water sorption can be calculated and, by integration, the amount of sorbed water is obtained. Amorphous lactose and cefadroxil undergo recrystallization when the moisture level in the surroundings exceeds the threshold values specific to each compound. During the sorption phase, heat is evolved fairly linearly as a function of consumed moisture, and also after the recrystallization, the heats indicate linear behavior. The heat values for the desorption phase of amorphous lactose and the adsorption of crystalline lactose coincide. With the different anhydrous forms of theophylline, the hydration takes place more rapidly in the metastable form 1, and generally, the process is more energetic in form 1. In all cases, the gravimetric results agree with the water sorption uptakes calculated from the calorimetric data. The technique introduced offers a rapid and sensitive method to gain new insights into the transitions in which vapors are involved. In addition, different kinds of surfaces with various energetics can now be studied more closely.

NSAID-activated gene 1 mediates pro-inflammatory signaling activation and paclitaxel chemoresistance in type I human epithelial ovarian cancer stem-like cells.

PubMed

Kim, Ki-Hyung; Park, Seong-Hwan; Do, Kee Hun; Kim, Juil; Choi, Kyung Un; Moon, Yuseok

2016-11-01

Epithelial ovarian cancer (EOC) remains the most lethal gynecologic malignancy in developed countries. Chronic endogenous sterile pro-inflammatory responses are strongly linked to EOC progression and chemoresistance to anti-cancer therapeutics. In the present study, the activity of epithelial NF-κB, a key pro-inflammatory transcription factor, was enhanced with the progress of EOC. This result was mechanistically linked with an increased expression of NSAID-Activated Gene 1 (NAG-1) in MyD88-positive type I EOC stem-like cells, compared with that in MyD88-negative type II EOC cells. Elevated NAG-1 as a potent biomarker of poor prognosis in the ovarian cancer was positively associated with the levels of NF-κB activation, chemokines and stemness markers in type I EOC cells. In terms of signal transduction, NAG-1-activated SMAD-linked and non-canonical TGFβ-activated kinase 1 (TAK-1)-activated pathways contributed to NF-κB activation and the subsequent induction of some chemokines and cancer stemness markers. In addition to effects on NF-κB-dependent gene regulation, NAG-1 was involved in expression of EGF receptor and subsequent activation of EGF receptor-linked signaling. The present study also provided evidences for links between NAG-1-linked signaling and chemoresistance in ovarian cancer cells. NAG-1 and pro-inflammatory NF-κB were positively associated with resistance to paclitaxel in MyD88-positive type I EOC cells. Mechanistically, this chemoresistance occurred due to enhanced activation of the SMAD-4- and non-SMAD-TAK-1-linked pathways. All of the present data suggested NAG-1 protein as a crucial mediator of EOC progression and resistance to the standard first-line chemotherapy against EOC, particularly in MyD88-positive ovarian cancer stem-like cells.

A Mechanism for the Temporal Potentiation of Genipin to the Cytotoxicity of Cisplatin in Colon Cancer Cells.

PubMed

Wang, Ruihua; MoYung, K C; Zhao, Y J; Poon, Karen

2016-01-01

To investigate the potentiation effect of Genipin to Cisplatin induced cell senescence in HCT-116 colon cancer cells in vitro. Cell viability was estimated by Propidium iodide and Hoechst 3342, reactive oxygen species (ROS) with DHE, mitochondrial membrane potential (MMP) with JC-1 MMP assay Kit and electron current production with microbial fuel cells (MFC). Genipin inhibited the UCP2 mediated anti-oxidative proton leak significantly promoted the Cisplatin induced ROS and subsequent cell death, which was similar to that of UCP2-siRNA. Cells treated with Cisplatin alone or combined with Genipin, ROS negatively, while MMP positively correlated with cell viability. Cisplatin induced ROS was significantly decreased by detouring electrons to MFC, or increased by Genipin combined treatment. Compensatory effects of UCP2 up-regulation with time against Genipin treatment were suggested. Shorter the Genipin treatment before Cisplatin better promoted the Cisplatin induced ROS and subsequent cell death. The interaction of leaked electron with Cisplatin was important during ROS generation. Inhibition of UCP2-mediated proton leak with Genipin potentiated the cytotoxicity of Cisplatin. Owing to the compensatory effects against Genipin, shorter Genipin treatment before Cisplatin was recommended in order to achieve better potentiation effect.

The diagnostic utility of Merkel cell polyomavirus immunohistochemistry in a fine needle aspirate of metastatic Merkel cell carcinoma of unknown primary to the pancreas.

PubMed

Li, Long; Molberg, Kyle; Cheedella, Naga; Thibodeaux, Joel; Hinson, Stacy; Lucas, Elena

2018-01-01

Merkel cell carcinoma (MCC) is an aggressive skin tumor with a high tendency for metastases. We report a case of MCC initially presenting as axillary and pancreatic metastases. A 33-year-old HIV-positive Hispanic male presented with a history of a rapidly growing axillary mass. A needle core biopsy demonstrated an epithelioid neoplasm composed of small to medium-sized cells with high nuclear-cytoplasmic ratio, nuclear molding, and frequent mitotic figures. A subsequent PET scan revealed a 1.5 cm FDG avid mass in the pancreas. Endoscopic ultrasound-guided FNA of the pancreatic mass showed neoplastic cells with similar morphology to those of the axillary mass. The tumor cells were positive with pancytokeratin AE1/AE3, CK20, CD56, synatophysin, chromogranin, and Merkel cell polyomavirus (MCPyV). This case of MCC most likely originated from a resolved primary skin lesion drained by the involved axillary lymph node with subsequent metastases to the pancreas and distant lymph nodes. © 2017 Wiley Periodicals, Inc.

Virus-like particle vaccine primes immune responses preventing inactivated-virus vaccine-enhanced disease against respiratory syncytial virus.

PubMed

Hwang, Hye Suk; Lee, Young-Tae; Kim, Ki-Hye; Ko, Eun-Ju; Lee, Youri; Kwon, Young-Man; Kang, Sang-Moo

2017-11-01

Formalin inactivated respiratory syncytial virus (FI-RSV) vaccination caused vaccine-enhanced respiratory disease (ERD) upon exposure to RSV in children. Virus-like particles presenting RSV F fusion protein (F VLP) are known to increase T helper type-1 (Th1) immune responses and avoid ERD in animal models. We hypothesized that F VLP would prime immune responses preventing ERD upon subsequent exposure to ERD-prone FI-RSV. Here, we demonstrated that heterologous F VLP priming and FI-RSV boosting of mice prevented FI-RSV vaccine-enhanced lung inflammation and eosinophilia upon RSV challenge. F VLP priming redirected pulmonary T cells toward effector CD8 T cells producing Th1 cytokines and significantly suppressed pulmonary Th2 cytokines. This study suggests that RSV F VLP priming would modulate and shift immune responses to subsequent exposure to ERD-prone FI-RSV vaccine and RSV infection, suppressing Th2 immune-mediated pulmonary histopathology and eosinophilia. Copyright © 2017. Published by Elsevier Inc.

ATP7B mediates vesicular sequestration of copper: insight into biliary copper excretion.

PubMed

Cater, Michael A; La Fontaine, Sharon; Shield, Kristy; Deal, Yolanda; Mercer, Julian F B

2006-02-01

The Wilson protein (ATP7B) regulates levels of systemic copper by excreting excess copper into bile. It is not clear whether ATP7B translocates excess intrahepatic copper directly across the canalicular membrane or sequesters this copper into exocytic vesicles, which subsequently fuse with canalicular membrane to expel their contents into bile. The aim of this study was to clarify the mechanism underlying ATP7B-mediated copper detoxification by investigating endogenous ATP7B localization in the HepG2 hepatoma cell line and its ability to mediate vesicular sequestration of excess intracellular copper. Immunofluorescence microscopy was used to investigate the effect of copper concentration on the localization of endogenous ATP7B in HepG2 cells. Copper accumulation studies to determine whether ATP7B can mediate vesicular sequestration of excess intracellular copper were performed using Chinese hamster ovary cells that exogenously expressed wild-type and mutant ATP7B proteins. In HepG2 cells, elevated copper levels stimulated trafficking of ATP7B to pericanalicular vesicles and not to the canalicular membrane as previously reported. Mutation of an endocytic retrieval signal in ATP7B caused the protein to constitutively localize to vesicles and not to the plasma membrane, suggesting that a vesicular compartment(s) is the final trafficking destination for ATP7B. Expression of wild-type and mutant ATP7B caused Chinese hamster ovary cells to accumulate copper in vesicles, which subsequently undergo exocytosis, releasing copper across the plasma membrane. This report provides compelling evidence that the primary mechanism of biliary copper excretion involves ATP7B-mediated vesicular sequestration of copper rather than direct copper translocation across the canalicular membrane.

Intercellular Calcium Waves in HeLa Cells Expressing GFP-labeled Connexin 43, 32, or 26

PubMed Central

Paemeleire, Koen; Martin, Patricia E. M.; Coleman, Sharon L.; Fogarty, Kevin E.; Carrington, Walter A.; Leybaert, Luc; Tuft, Richard A.; Evans, W. Howard; Sanderson, Michael J.

2000-01-01

This study was undertaken to obtain direct evidence for the involvement of gap junctions in the propagation of intercellular Ca2+ waves. Gap junction-deficient HeLa cells were transfected with plasmids encoding for green fluorescent protein (GFP) fused to the cytoplasmic carboxyl termini of connexin 43 (Cx43), 32 (Cx32), or 26 (Cx26). The subsequently expressed GFP-labeled gap junctions rendered the cells dye- and electrically coupled and were detected at the plasma membranes at points of contact between adjacent cells. To correlate the distribution of gap junctions with the changes in [Ca2+]i associated with Ca2+ waves and the distribution of the endoplasmic reticulum (ER), cells were loaded with fluorescent Ca2+-sensitive (fluo-3 and fura-2) and ER membrane (ER-Tracker) dyes. Digital high-speed microscopy was used to collect a series of image slices from which the three-dimensional distribution of the gap junctions and ER were reconstructed. Subsequently, intercellular Ca2+ waves were induced in these cells by mechanical stimulation with or without extracellular apyrase, an ATP-degrading enzyme. In untransfected HeLa cells and in the absence of apyrase, cell-to-cell propagating [Ca2+]i changes were characterized by initiating Ca2+ puffs associated with the perinuclear ER. By contrast, in Cx–GFP-transfected cells and in the presence of apyrase, [Ca2+]i changes were propagated without initiating perinuclear Ca2+ puffs and were communicated between cells at the sites of the Cx–GFP gap junctions. The efficiency of Cx expression determined the extent of Ca2+ wave propagation. These results demonstrate that intercellular Ca2+ waves may be propagated simultaneously via an extracellular pathway and an intracellular pathway through gap junctions and that one form of communication may mask the other. PMID:10793154

Why solid oxide cells can be reversibly operated in solid oxide electrolysis cell and fuel cell modes?

PubMed

Chen, Kongfa; Liu, Shu-Sheng; Ai, Na; Koyama, Michihisa; Jiang, San Ping

2015-12-14

High temperature solid oxide cells (SOCs) are attractive for storage and regeneration of renewable energy by operating reversibly in solid oxide electrolysis cell (SOEC) and solid oxide fuel cell (SOFC) modes. However, the stability of SOCs, particularly the deterioration of the performance of oxygen electrodes in the SOEC operation mode, is the most critical issue in the development of high performance and durable SOCs. In this study, we investigate in detail the electrochemical activity and stability of La0.8Sr0.2MnO3 (LSM) oxygen electrodes in cyclic SOEC and SOFC modes. The results show that the deterioration of LSM oxygen electrodes caused by anodic polarization can be partially or completely recovered by subsequent cathodic polarization. Using in situ assembled LSM electrodes without pre-sintering, we demonstrate that the deteriorated LSM/YSZ interface can be repaired and regenerated by operating the cells under cathodic polarization conditions. This study for the first time establishes the foundation for the development of truly reversible and stable SOCs for hydrogen fuel production and electricity generation in cyclic SOEC and SOFC operation modes.

The DNA Inflammasome in Human Myeloid Cells Is Initiated by a STING-Cell Death Program Upstream of NLRP3

PubMed Central

Gaidt, Moritz M.; Ebert, Thomas S.; Chauhan, Dhruv; Ramshorn, Katharina; Pinci, Francesca; Zuber, Sarah; O’Duill, Fionan; Schmid-Burgk, Jonathan L.; Hoss, Florian; Buhmann, Raymund; Wittmann, Georg; Latz, Eicke; Subklewe, Marion; Hornung, Veit

2018-01-01

Summary Detection of cytosolic DNA constitutes a central event in the context of numerous infectious and sterile inflammatory conditions. Recent studies have uncovered a bipartite mode of cytosolic DNA recognition, in which the cGAS-STING axis triggers antiviral immunity, whereas AIM2 triggers inflammasome activation. Here, we show that AIM2 is dispensable for DNA-mediated inflammasome activation in human myeloid cells. Instead, detection of cytosolic DNA by the cGAS-STING axis induces a cell death program initiating potassium efflux upstream of NLRP3. Forward genetics identified regulators of lysosomal trafficking to modulate this cell death program, and subsequent studies revealed that activated STING traffics to the lysosome, where it triggers membrane permeabilization and thus lysosomal cell death (LCD). Importantly, the cGAS-STING-NLRP3 pathway constitutes the default inflammasome response during viral and bacterial infections in human myeloid cells. We conclude that targeting the cGAS-STING-LCD-NLRP3 pathway will ameliorate pathology in inflammatory conditions that are associated with cytosolic DNA sensing. PMID:29033128

Minocycline promotes the generation of dendritic cells with regulatory properties.

PubMed

Kim, Narae; Park, Chan-Su; Im, Sun-A; Kim, Ji-Wan; Lee, Jae-Hee; Park, Young-Jun; Song, Sukgil; Lee, Chong-Kil

2016-08-16

Minocycline, which has long been used as a broad-spectrum antibiotic, also exhibits non-antibiotic properties such as inhibition of inflammation and angiogenesis. In this study, we show that minocycline significantly enhances the generation of dendritic cells (DCs) from mouse bone marrow (BM) cells when used together with GM-CSF and IL-4. DCs generated from BM cells in the presence of minocycline (Mino-DCs) demonstrate the characteristics of regulatory DCs. Compared with control DCs, Mino-DCs are resistant to subsequent maturation stimuli, impaired in MHC class II-restricted exogenous Ag presentation, and show decreased cytokine secretion. Mino-DCs also show decreased ability to prime allogeneic-specific T cells, while increasing the expansion of CD4+CD25+Foxp3+ T regulatory cells both in vitro and in vivo. In addition, pretreatment with MOG35-55 peptide-pulsed Mino-DCs ameliorates clinical signs of experimental autoimmune encephalitis induced by MOG peptide injection. Our study identifies minocycline as a new pharmacological agent that could be potentially used to increase the production of regulatory DCs for cell therapy to treat autoimmune disorders, allergy, and transplant rejection.

Fate vs choice: the immune system reloaded.

PubMed

Murphy, Kenneth M

2005-01-01

Development can occur by either instructive or stochastic processes. My colleagues and I have studied the contributions of these processes to differentiation of naïve CD4+ T-cells to either a Th1 or Th2 phenotype. Our initial discovery that pathogens in our in vitro priming system led to the development of Th1 cells through the action of interleukin-12 was important evidence of a link between innate and adaptive immunity. Subsequent studies in our laboratory revealed an important role for GATA-3 autoactivation in Th2 development. Other interesting projects that have emerged as a result of our Th cell differentiation studies include understanding the role of the inhibitory immunoreceptor B- and T-lymphocyte attenuator in the immune response, as well as the role of the transcription factor ERM in both T-cells and spermatogenesis. We currently maintain our interests in the Th differentiation field by trying to understand the role of type 1 interferons in Th1 development and the role of alternate promoters for the GATA-3 gene, among other things, but are also actively embarking on studies related to the choice between divergent cell types during embryonic stem cell differentiation.

Differential effects of protein phosphatases in the recycling of metabotropic glutamate receptor 5.

PubMed

Mahato, P K; Pandey, S; Bhattacharyya, S

2015-10-15

The major excitatory neurotransmitter Glutamate acts on both ionotropic and metabotropic glutamate receptors (mGluRs) in the central nervous system. mGluR5, a member of the group I mGluR family is widely expressed throughout the brain and plays important roles in a variety of neuronal processes including various forms of synaptic plasticity. This receptor is also involved in various neuropsychiatric disorders, viz., Fragile X syndrome, autism etc. It has been reported that mGluR5 undergoes desensitization and subsequently internalization on ligand exposure in various cell types. However, the downstream events after the internalization and the molecular players involved in the post-endocytic events of this receptor have not been studied. In the present study, we find that subsequent to internalization mGluR5 enters the recycling compartment. After that the receptor recycles back to the cell surface. We also show here that the recycling of mGluR5 is dependent on protein phosphatases. Our data suggest that mGluR5 recycling is completely dependent on the activity of PP2A whereas, PP2B has partial effect on this process. Thus our study suggests that mGluR5 recycles back to the cell surface after ligand-dependent internalization and protein phosphatases that have been implicated in various forms of synaptic plasticity have differential effects on the recycling of mGluR5. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Automated Tracking of Cell Migration with Rapid Data Analysis.

PubMed

DuChez, Brian J

2017-09-01

Cell migration is essential for many biological processes including development, wound healing, and metastasis. However, studying cell migration often requires the time-consuming and labor-intensive task of manually tracking cells. To accelerate the task of obtaining coordinate positions of migrating cells, we have developed a graphical user interface (GUI) capable of automating the tracking of fluorescently labeled nuclei. This GUI provides an intuitive user interface that makes automated tracking accessible to researchers with no image-processing experience or familiarity with particle-tracking approaches. Using this GUI, users can interactively determine a minimum of four parameters to identify fluorescently labeled cells and automate acquisition of cell trajectories. Additional features allow for batch processing of numerous time-lapse images, curation of unwanted tracks, and subsequent statistical analysis of tracked cells. Statistical outputs allow users to evaluate migratory phenotypes, including cell speed, distance, displacement, and persistence, as well as measures of directional movement, such as forward migration index (FMI) and angular displacement. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

Transdifferentiation mediated tumor suppression by the endoplasmic reticulum stress sensor IRE-1 in C. elegans

PubMed Central

Levi-Ferber, Mor; Gian, Hai; Dudkevich, Reut; Henis-Korenblit, Sivan

2015-01-01

Deciphering effective ways to suppress tumor progression and to overcome acquired apoptosis resistance of tumor cells are major challenges in the tumor therapy field. We propose a new concept by which tumor progression can be suppressed by manipulating tumor cell identity. In this study, we examined the effect of ER stress on apoptosis resistant tumorous cells in a Caenorhabditis elegans germline tumor model. We discovered that ER stress suppressed the progression of the lethal germline tumor by activating the ER stress sensor IRE-1. This suppression was associated with the induction of germ cell transdifferentiation into ectopic somatic cells. Strikingly, transdifferentiation of the tumorous germ cells restored their ability to execute apoptosis and enabled their subsequent removal from the gonad. Our results indicate that tumor cell transdifferentiation has the potential to combat cancer and overcome the escape of tumor cells from the cell death machinery. DOI: http://dx.doi.org/10.7554/eLife.08005.001 PMID:26192965

Helicobacter pylori shows asymmetric and polar cell divisome assembly associated with DNA replisome.

PubMed

Kamran, Mohammad; Dubey, Priyanka; Verma, Vijay; Dasgupta, Santanu; Dhar, Suman K

2018-05-09

DNA replication and cell division are two fundamental processes in the life cycle of a cell. The majority of prokaryotic cells undergo division by means of binary fission in coordination with replication of the genome. Both processes, but especially their coordination, are poorly understood in Helicobacter pylori. Here, we studied the cell divisome assembly and the subsequent processes of membrane and peptidoglycan synthesis in the bacterium. To our surprise, we found the cell divisome assembly to be polar, which was well-corroborated by the asymmetric membrane and peptidoglycan synthesis at the poles. The divisome components showed its assembly to be synchronous with that of the replisome and the two remained associated throughout the cell cycle, demonstrating a tight coordination among chromosome replication, segregation and cell division in H. pylori. To our knowledge, this is the first report where both DNA replication and cell division along with their possible association have been demonstrated for this pathogenic bacterium. © 2018 Federation of European Biochemical Societies.

Genetics Home Reference: infantile-onset ascending hereditary spastic paralysis

MedlinePlus

... cell membrane to the interior of the cell (endocytosis), and the development of specialized structures called axons ... the subsequent loss of GTPase functions, such as endocytosis and the development of axons and dendrites, contribute ...

Identification of Multipotent Stem/Progenitor Cells in Murine Sclera

PubMed Central

Tsai, Chia-Ling; Wu, Pei-Chang; Fini, M. Elizabeth; Shi, Songtao

2011-01-01

Purpose. The sclera forms the fibrous outer coat of the eyeball and acts as a supportive framework. The purpose of this study was to examine whether the sclera contains mesenchymal stem/progenitor cells. Method. Scleral tissue from C57BL6/J mice was separated from the retina and choroid and subsequently enzyme digested to release single cells. Proliferation capacity, self-renewal capacity, and ability for multipotent differentiation were analyzed by BrdU labeling, flow cytometry, reverse transcriptase–polymerase chain reaction, immunocytochemistry, and in vivo transplantation. Results. The scleral stem/progenitor cells (SSPCs) possessed clonogenic and high doubling capacities. These cells were positive for the mesenchymal markers Sca-1, CD90.2, CD44, CD105, and CD73 and negative for the hematopoietic markers CD45, CD11b, Flk1, CD34, and CD117. In addition to expressing stem cell genes ABCG2, Six2, Notch1, and Pax6, SSPCs were able to differentiate to adipogenic, chondrogenic, and neurogenic lineages. Conclusions. This study indicates that the sclera contains multipotent mesenchymal stem cells. Further study of SSPCs may help elucidate the cellular and molecular mechanism of scleral diseases such as scleritis and myopia. PMID:21788434

EFFECT OF PHOSPHORUS CONCENTRATION ON THE GROWTH OF CATTAIL CALLUS CELLS

EPA Science Inventory

This investigation examined the growth of Typha latifolia (cattail) callus cells grown in 5 different (0, 11, 22, 33, 44, jg/L(-1) phosphosur concentrations. The cells were grown for two successive subcultures on semi-solid media, and subsequently in suspension culture with the s...

Risk of brain tumors from wireless phone use.

PubMed

Dubey, Rash Bihari; Hanmandlu, Madasu; Gupta, Suresh Kumar

2010-01-01

The debate regarding the health effects of low-intensity electromagnetic radiation from sources such as power lines, base stations, and cell phones has recently been reignited. Wireless communication has dramatically influenced our lifestyle; its impact on human health has not been completely assessed. Widespread concern continues in the community about the deleterious effects of radiofrequency radiations on human tissues and the subsequent potential threat of carcinogenesis. Exposure to low-frequency electromagnetic field has been linked to a variety of adverse health outcomes. This article surveys the results of early cell phone studies, where exposure duration was too short to expect tumor genesis, and 2 sets of more recent studies with longer exposure duration: the Interphone studies and the Swedish studies led by Hardell.

Antibody Persistence in Adults Two Years after Vaccination with an H1N1 2009 Pandemic Influenza Virus-Like Particle Vaccine

PubMed Central

Villasís-Keever, Miguel Ángel; Núñez-Valencia, Adriana; Boscó-Gárate, Ilka; Lozano-Dubernard, Bernardo; Lara-Puente, Horacio; Espitia, Clara; Alpuche-Aranda, Celia; Bonifaz, Laura C.; Arriaga-Pizano, Lourdes; Pastelin-Palacios, Rodolfo; Isibasi, Armando; López-Macías, Constantino

2016-01-01

The influenza virus is a human pathogen that causes epidemics every year, as well as potential pandemic outbreaks, as occurred in 2009. Vaccination has proven to be sufficient in the prevention and containment of viral spreading. In addition to the current egg-based vaccines, new and promising vaccine platforms, such as cell culture-derived vaccines that include virus-like particles (VLPs), have been developed. VLPs have been shown to be both safe and immunogenic against influenza infections. Although antibody persistence has been studied in traditional egg-based influenza vaccines, studies on antibody response durations induced by VLP influenza vaccines in humans are scarce. Here, we show that subjects vaccinated with an insect cell-derived VLP vaccine, in the midst of the 2009 H1N1 influenza pandemic outbreak in Mexico City, showed antibody persistence up to 24 months post-vaccination. Additionally, we found that subjects that reported being revaccinated with a subsequent inactivated influenza virus vaccine showed higher antibody titres to the pandemic influenza virus than those who were not revaccinated. These findings provide insights into the duration of the antibody responses elicited by an insect cell-derived pandemic influenza VLP vaccine and the possible effects of subsequent influenza vaccination on antibody persistence induced by this VLP vaccine in humans. PMID:26919288

Inhibition of the NF-κB pathway as a candidate therapeutic strategy for cryopyrin-associated periodic syndrome.

PubMed

Shimogaki, Satoka; Ito, Sayaka; Komatsu, Sachiyo; Koike, Ryuji; Miyasaka, Nobuyuki; Umezawa, Kazuo; Kubota, Tetsuo

2014-05-01

Cryopyrin-associated periodic syndrome (CAPS) is caused by unrestricted IL-1β release due to mutation of the gene coding NLRP3. This study aimed to clarify whether NLRP3-related IL-1β release is dependent on the NF-κB pathway. Peripheral blood mononuclear cells (PBMCs) from healthy subjects or patients with Muckle-Wells syndrome were primed with LPS and subsequently stimulated by ATP. Human umbilical vein endothelial cells (HUVECs) were cultured with the supernatant obtained from LPS-plus ATP-stimulated PBMCs. Expression of proinflammatory molecules was estimated using RT-PCR, ELISA or immunochemical staining, in the presence or absence of an NF-κB inhibitor (-)-dehydroxymethylepoxyquinomicin (DHMEQ). DHMEQ inhibited expression of proIL-1β and NLRP3 by normal PBMCs primed with LPS, resulting in inhibition of caspase-1 activation and IL-1β secretion by the cells after subsequent stimulation with ATP. DHMEQ also inhibited expression of IL-1β, TNFα, IL-6 and VCAM-1 by HUVECs. Patient cells released IL-1β spontaneously or by ATP-stimulation even without LPS-priming. Both the spontaneous and stimulated IL-1β releases were inhibited by DHMEQ without affecting viability of the cells. These results clearly indicate that IL-1β production through the NLRP3 inflammasome is dependent on the NF-κB pathway, which could be a good target for the development of a novel therapeutic strategy for CAPS.

Evaluating 3D bone tissue engineered constructs with different seeding densities using the alamarBlue assay and the effect on in vivo bone formation.

PubMed

Wilson, C E; Dhert, W J A; Van Blitterswijk, C A; Verbout, A J; De Bruijn, J D

2002-12-01

Bone tissue engineering using patient derived cells seeded onto porous scaffolds has gained much attention in recent years. Evaluating the viability of these 3D constructs is an essential step in optimizing the process. The alamarBlue (aB) assay was evaluated for its potential to follow in vitro cell proliferation on architecturally standardized hydroxyapatite scaffolds. The impact of the aB assayed and seeding density on subsequent in vivo bone formation was investigated. Twelve scaffolds were seeded with various densities from 250 to 2.5x10(6) cells/scaffold and assay by aB at 5 time points during the 7-day culture period. Twelve additional scaffolds were seeded with 2.5x10(5) cells/scaffold. Two control and 2 aB treated scaffolds were subcutaneously implanted into each of 6 nude mice for 6 weeks. Four observers ranked bone formation using a pair wise comparison of histological sections form each mouse. The aB assay successfully followed cell proliferation, however, the diffusion kinetics of the 3D constructs must be considered. The influence of in vitro aB treatment on subsequent in vivo bone formation cannot be ruled out but was not shown to be significant in the current study. The aB assay appears to be quite promising for evaluating a maximum or end-point viability of 3D tissue engineered constructs. Finally, higher seeding densities resulted in more observed bone formation.

Metabolism of Acrylate to β-Hydroxypropionate and Its Role in Dimethylsulfoniopropionate Lyase Induction by a Salt Marsh Sediment Bacterium, Alcaligenes faecalis M3A

PubMed Central

Ansede, John H.; Pellechia, Perry J.; Yoch, Duane C.

1999-01-01

Dimethylsulfoniopropionate (DMSP) is degraded to dimethylsulfide (DMS) and acrylate by the enzyme DMSP lyase. DMS or acrylate can serve as a carbon source for both free-living and endophytic bacteria in the marine environment. In this study, we report on the mechanism of DMSP-acrylate metabolism by Alcaligenes faecalis M3A. Suspensions of citrate-grown cells expressed a low level of DMSP lyase activity that could be induced to much higher levels in the presence of DMSP, acrylate, and its metabolic product, β-hydroxypropionate. DMSP was degraded outside the cell, resulting in an extracellular accumulation of acrylate, which in suspensions of citrate-grown cells was then metabolized at a low endogenous rate. The inducible nature of acrylate metabolism was evidenced by both an increase in the rate of its degradation over time and the ability of acrylate-grown cells to metabolize this molecule at about an eight times higher rate than citrate-grown cells. Therefore, acrylate induces both its production (from DMSP) and its degradation by an acrylase enzyme. 1H and 13C nuclear magnetic resonance analyses were used to identify the products resulting from [1-13C]acrylate metabolism. The results indicated that A. faecalis first metabolized acrylate to β-hydroxypropionate outside the cell, which was followed by its intracellular accumulation and subsequent induction of DMSP lyase activity. In summary, the mechanism of DMSP degradation to acrylate and the subsequent degradation of acrylate to β-hydroxypropionate in the aerobic β-Proteobacterium A. faecalis has been described. PMID:10543825

Infection of Mosquito Cells (C6/36) by Dengue-2 Virus Interferes with Subsequent Infection by Yellow Fever Virus.

PubMed

Abrao, Emiliana Pereira; da Fonseca, Benedito Antônio Lopes

2016-02-01

Dengue is one of the most important diseases caused by arboviruses in the world. Yellow fever is another arthropod-borne disease of great importance to public health that is endemic to tropical regions of Africa and the Americas. Both yellow fever and dengue viruses are flaviviruses transmitted by Aedes aegypti mosquitoes, and then, it is reasonable to consider that in a given moment, mosquito cells could be coinfected by both viruses. Therefore, we decided to evaluate if sequential infections of dengue and yellow fever viruses (and vice-versa) in mosquito cells could affect the virus replication patterns. Using immunofluorescence and real-time PCR-based replication assays in Aedes albopictus C6/36 cells with single or sequential infections with both viruses, we demonstrated the occurrence of viral interference, also called superinfection exclusion, between these two viruses. Our results show that this interference pattern is particularly evident when cells were first infected with dengue virus and subsequently with yellow fever virus (YFV). Reduction in dengue virus replication, although to a lower extent, was also observed when C6/36 cells were initially infected with YFV followed by dengue virus infection. Although the importance that these findings have on nature is unknown, this study provides evidence, at the cellular level, of the occurrence of replication interference between dengue and yellow fever viruses and raises the question if superinfection exclusion could be a possible explanation, at least partially, for the reported lack of urban yellow fever occurrence in regions where a high level of dengue transmission occurs.

Rationally optimized cryopreservation of multiple mouse embryonic stem cell lines: II—Mathematical prediction and experimental validation of optimal cryopreservation protocols☆

PubMed Central

Kashuba, Corinna M.; Benson, James D.; Critser, John K.

2014-01-01

In Part I, we documented differences in cryopreservation success measured by membrane integrity in four mouse embryonic stem cell (mESC) lines from different genetic backgrounds (BALB/c, CBA, FVB, and 129R1), and we demonstrated a potential biophysical basis for these differences through a comparative study characterizing the membrane permeability characteristics and osmotic tolerance limits of each cell line. Here we use these values to predict optimal cryoprotectants, cooling rates, warming rates, and plunge temperatures. We subsequently verified these predictions experimentally for their effects on post-thaw recovery. From this study, we determined that a cryopreservation protocol utilizing 1 M propylene glycol, a cooling rate of 1 °C/minute, and plunging into liquid nitrogen at −41 °C, combined with subsequent warming in a 22 °C water bath with agitation, significantly improved post-thaw recovery for three of the four mESC lines, and did not diminish post-thaw recovery for our single exception. It is proposed that this protocol can be successfully applied to most mESC lines beyond those included within this study once the effect of propylene glycol on mESC gene expression, growth characteristics, and germ-line transmission has been determined. Mouse ESC lines with poor survival using current standard cryopreservation protocols or our proposed protocol can be optimized on a case-by-case basis using the method we have outlined over two papers. For our single exception, the CBA cell line, a cooling rate of 5 °C/minute in the presence of 1.0 M dimethyl sulfoxide or 1.0 M propylene glycol, combined with plunge temperature of −80 °C was optimal. PMID:24560712

Changes in beta cell function during the proximate post-diagnosis period in persons with type 1 diabetes.

PubMed

DiMeglio, Linda A; Cheng, Peiyao; Beck, Roy W; Kollman, Craig; Ruedy, Katrina J; Slover, Robert; Aye, Tandy; Weinzimer, Stuart A; Bremer, Andrew A; Buckingham, Bruce

2016-06-01

Prior studies examining beta-cell preservation in type 1 diabetes have predominantly assessed stimulated C-peptide concentrations approximately 10 wk after diagnosis. We examined whether earlier assessments might aid in prediction of beta cell function over time. Using data from a multi-center randomized trial assessing the effect of intensive diabetes management initiated within 1 wk of diagnosis, we assessed which clinical factors predicted 90-min mixed-meal tolerance test (MMTT) stimulated C-peptide values obtained 2 and 6 wk after diagnosis. We also studied associations of these factors with C-peptide values at 1- and 2-year post-diagnosis. Data from intervention and control groups were pooled. Among 67 study participants (mean age 13.3 ± 5.7 yr, range 7.8-45.7 yr) in multivariable analyses, C-peptide increased from baseline to 2 wks and then 6 wk. C-peptide levels at these times were significantly correlated with 1- and 2-yr C-peptide concentrations (all p < 0.001), with the strongest observed associations between 6-wk C-peptide and the 1- and 2-yr values (r = 0.66 and r = 0.61, respectively). In multivariable analyses, greater baseline and 6-wk C-peptide, and older age independently predicted greater 1- and 2-yr C-peptide concentrations. C-peptide assessments close to diagnosis were predictive of subsequent C-peptide production. Our data demonstrate a clear increase in C-peptide over the initial 6 wk after diabetes diagnosis followed by a plateau. Our data do not suggest that MMTT assessments performed closer to diagnosis than 6 wk would improve prediction of subsequent residual beta cell function. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Young investigator challenge: Validation and optimization of immunohistochemistry protocols for use on cellient cell block specimens.

PubMed

Sauter, Jennifer L; Grogg, Karen L; Vrana, Julie A; Law, Mark E; Halvorson, Jennifer L; Henry, Michael R

2016-02-01

The objective of the current study was to establish a process for validating immunohistochemistry (IHC) protocols for use on the Cellient cell block (CCB) system. Thirty antibodies were initially tested on CCBs using IHC protocols previously validated on formalin-fixed, paraffin-embedded tissue (FFPE). Cytology samples were split to generate thrombin cell blocks (TCB) and CCBs. IHC was performed in parallel. Antibody immunoreactivity was scored, and concordance or discordance in immunoreactivity between the TCBs and CCBs for each sample was determined. Criteria for validation of an antibody were defined as concordant staining in expected positive and negative cells, in at least 5 samples each, and concordance in at least 90% of the samples total. Antibodies that failed initial validation were retested after alterations in IHC conditions. Thirteen of the 30 antibodies (43%) did not meet initial validation criteria. Of those, 8 antibodies (calretinin, clusters of differentiation [CD] 3, CD20, CDX2, cytokeratin 20, estrogen receptor, MOC-31, and p16) were optimized for CCBs and subsequently validated. Despite several alterations in conditions, 3 antibodies (Ber-EP4, D2-40, and paired box gene 8 [PAX8]) were not successfully validated. Nearly one-half of the antibodies tested in the current study failed initial validation using IHC conditions that were established in the study laboratory for FFPE material. Although some antibodies subsequently met validation criteria after optimization of conditions, a few continued to demonstrate inadequate immunoreactivity. These findings emphasize the importance of validating IHC protocols for methanol-fixed tissue before clinical use and suggest that optimization for alcohol fixation may be needed to obtain adequate immunoreactivity on CCBs. © 2016 American Cancer Society.

Influence of Post-Heat Treatment of ZnO:Al Transparent Electrode for Copper Indium Gallium Selenide Thin Film Solar Cell.

PubMed

Eom, Taewoo; Park, Jeong Eun; Park, Sang Yong; Park, Jeong Hoon; Bweupe, Jackson; Lim, Donggun

2018-09-01

Copper indium gallium selenide (CIGS) thin film solar cells have been regarded as a candidate for energy conversion devices owing to their high absorption coefficient, high temperature stability, and low cost. ZnO:Al thin film is commonly used in CIGS solar cells as a window layer. In this study, ZnO:Al films were deposited on glass under various post-heat temperature using RF sputtering to observe the characteristics of ZnO:Al films such as Hall mobility, carrier concentration, and resistivity; subsequently, the ZnO:Al films were applied to a CIGS solar cell as a window. CIGS solar cells fabricated with various ZnO:Al films were analyzed in order to investigate their influence. The test results showed that the improvement of ZnO:Al characteristics affects Jsc and Voc in the solar cell through reduced recombination and increase of optical property.

Indole-3- carbinol enhances sorafenib cytotoxicity in hepatocellular carcinoma cells: A mechanistic study.

PubMed

Abdelmageed, Mai M; El-Naga, Reem N; El-Demerdash, Ebtehal; Elmazar, Mohamed M

2016-09-09

Sorafenib is the only chemotherapeutic agent currently approved for unresectable hepatocellular carcinoma (HCC). However, poor response rates have been widely reported. Indole-3-carbinol (I3C) is a potential chemopreventive phytochemical. The present study aimed to explore the potential chemomodulatory effects of I3C on sorafenib in HCC cells as well as the possible underlying mechanisms. I3C exhibited a greater cytotoxicity in HepG2 cells compared to Huh-7 cells (p < 0.0001). Moreover, the co-treatment of HepG2 cells with I3C and sorafenib was more effective (p = 0.002). Accordingly, subsequent mechanistic studies were carried on HepG2 cells. The results show that the ability of I3C to enhance sorafenib cytotoxicity in HCC cells could be partially attributed to increasing the apoptotic activity and decreasing the angiogenic potentials. The combination had a negative effect on epithelial-mesenchymal transition (EMT). Increased NOX-1 expression was also observed which may indicate the involvement of NOX-1 in I3C chemomodulatory effects. Additionally, the combination induced cell cycle arrest at the G0/G1 phase. In conclusion, these findings provide evidence that I3C enhances sorafenib anti-cancer activity in HCC cells.

Indole-3- carbinol enhances sorafenib cytotoxicity in hepatocellular carcinoma cells: A mechanistic study

PubMed Central

Abdelmageed, Mai M.; El-Naga, Reem N.; El-Demerdash, Ebtehal; Elmazar, Mohamed M.

2016-01-01

Sorafenib is the only chemotherapeutic agent currently approved for unresectable hepatocellular carcinoma (HCC). However, poor response rates have been widely reported. Indole-3-carbinol (I3C) is a potential chemopreventive phytochemical. The present study aimed to explore the potential chemomodulatory effects of I3C on sorafenib in HCC cells as well as the possible underlying mechanisms. I3C exhibited a greater cytotoxicity in HepG2 cells compared to Huh-7 cells (p < 0.0001). Moreover, the co-treatment of HepG2 cells with I3C and sorafenib was more effective (p = 0.002). Accordingly, subsequent mechanistic studies were carried on HepG2 cells. The results show that the ability of I3C to enhance sorafenib cytotoxicity in HCC cells could be partially attributed to increasing the apoptotic activity and decreasing the angiogenic potentials. The combination had a negative effect on epithelial-mesenchymal transition (EMT). Increased NOX-1 expression was also observed which may indicate the involvement of NOX-1 in I3C chemomodulatory effects. Additionally, the combination induced cell cycle arrest at the G0/G1 phase. In conclusion, these findings provide evidence that I3C enhances sorafenib anti-cancer activity in HCC cells. PMID:27612096

Germination and Outgrowth of Single Spores of Saccharomyces cerevisiae Viewed by Scanning Electron and Phase-Contrast Microscopy

PubMed Central

Rousseau, Paul; Halvorson, Harlyn O.; Bulla, Lee A.; Julian, Grant St.

1972-01-01

Single spores of Saccharomyces cerevisiae were examined during germination and outgrowth by scanning electron and phase-contrast microscopy. Also determined were changes in cell weight and light absorbance, trehalose utilization, and synthesis of protein and KOH-soluble carbohydrates. These studies reveal that development of the vegetative cell from a spore follows a definite sequence of events involving dramatic physical and chemical modifications. These changes are: initial rapid loss in cellular absorbance followed later by an abrupt gain in absorbance; reduction in cell weight and a subsequent progressive increase; modification of the spore surface with concomitant diminution in refractility; elongation of the cell and augmentation of surface irregularities; rapid decline in trehalose content of the cell accompanied by extensive formation of KOH-soluble carbohydrates; and bud formation. Images PMID:4551750

Isolation of skeletal muscle stem cells by fluorescence-activated cell sorting.

PubMed

Liu, Ling; Cheung, Tom H; Charville, Gregory W; Rando, Thomas A

2015-10-01

The prospective isolation of purified stem cell populations has dramatically altered the field of stem cell biology, and it has been a major focus of research across tissues in different organisms. Muscle stem cells (MuSCs) are now among the most intensely studied stem cell populations in mammalian systems, and the prospective isolation of these cells has allowed cellular and molecular characterizations that were not dreamed of a decade ago. In this protocol, we describe how to isolate MuSCs from limb muscles of adult mice by fluorescence-activated cell sorting (FACS). We provide a detailed description of the physical and enzymatic dissociation of mononucleated cells from limb muscles, a procedure that is essential in order to maximize cell yield. We also describe a FACS-based method that is used subsequently to obtain highly pure populations of either quiescent or activated MuSCs (VCAM(+)CD31(-)CD45(-)Sca1(-)). The isolation process takes ∼5-6 h to complete. The protocol also allows for the isolation of endothelial cells, hematopoietic cells and mesenchymal stem cells from muscle tissue.

An Elmo–Dock complex locally controls Rho GTPases and actin remodeling during cadherin-mediated adhesion

PubMed Central

Collins, Caitlin

2014-01-01

Cell–cell contact formation is a dynamic process requiring the coordination of cadherin-based cell–cell adhesion and integrin-based cell migration. A genome-wide RNA interference screen for proteins required specifically for cadherin-dependent cell–cell adhesion identified an Elmo–Dock complex. This was unexpected as Elmo–Dock complexes act downstream of integrin signaling as Rac guanine-nucleotide exchange factors. In this paper, we show that Elmo2 recruits Dock1 to initial cell–cell contacts in Madin–Darby canine kidney cells. At cell–cell contacts, both Elmo2 and Dock1 are essential for the rapid recruitment and spreading of E-cadherin, actin reorganization, localized Rac and Rho GTPase activities, and the development of strong cell–cell adhesion. Upon completion of cell–cell adhesion, Elmo2 and Dock1 no longer localize to cell–cell contacts and are not required subsequently for the maintenance of cell–cell adhesion. These studies show that Elmo–Dock complexes are involved in both integrin- and cadherin-based adhesions, which may help to coordinate the transition of cells from migration to strong cell–cell adhesion. PMID:25452388

The biology of NK cells and their receptors affects clinical outcomes after hematopoietic cell transplantation (HCT).

PubMed

Foley, Bree; Felices, Martin; Cichocki, Frank; Cooley, Sarah; Verneris, Michael R; Miller, Jeffrey S

2014-03-01

Natural killer (NK) cells were first identified for their capacity to reject bone marrow allografts in lethally irradiated mice without prior sensitization. Subsequently, human NK cells were detected and defined by their non-major histocompatibility complex (MHC)-restricted cytotoxicity toward transformed or virally infected target cells. Karre et al. later proposed 'the missing self hypothesis' to explain the mechanism by which self-tolerant cells could kill targets that had lost self MHC class I. Subsequently, the receptors that recognize MHC class I to mediate tolerance in the host were identified on NK cells. These class I-recognizing receptors contribute to the acquisition of function by a dynamic process known as NK cell education or licensing. In the past, NK cells were assumed to be short lived, but more recently NK cells have been shown to mediate immunologic memory to secondary exposures to cytomegalovirus infection. Because of their ability to lyse tumors with aberrant MHC class I expression and to produce cytokines and chemokines upon activation, NK cells may be primed by many stimuli, including viruses and inflammation, to contribute to a graft-versus-tumor effect. In addition, interactions with other immune cells support the therapeutic potential of NK cells to eradicate tumor and to enhance outcomes after hematopoietic cell transplantation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Subcellular distribution of glutathione and its dynamic changes under oxidative stress in the yeast Saccharomyces cerevisiae

PubMed Central

Zechmann, Bernd; Liou, Liang-Chun; Koffler, Barbara E; Horvat, Lucija; Tomašić, Ana; Fulgosi, Hrvoje; Zhang, Zhaojie

2011-01-01

Glutathione is an important antioxidant in most prokaryotes and eukaryotes. It detoxifies reactive oxygen species and is also involved in the modulation of gene expression, in redox signaling, and in the regulation of enzymatic activities. In this study, the subcellular distribution of glutathione was studied in Saccharomyces cerevisiae by quantitative immunoelectron microscopy. Highest glutathione contents were detected in mitochondria and subsequently in the cytosol, nuclei, cell walls, and vacuoles. The induction of oxidative stress by hydrogen peroxide (H2O2) led to changes in glutathione-specific labeling. Three cell types were identified. Cell types I and II contained more glutathione than control cells. Cell type II differed from cell type I in showing a decrease in glutathione-specific labeling solely in mitochondria. Cell type III contained much less glutathione contents than the control and showed the strongest decrease in mitochondria, suggesting that high and stable levels of glutathione in mitochondria are important for the protection and survival of the cells during oxidative stress. Additionally, large amounts of glutathione were relocated and stored in vacuoles in cell type III, suggesting the importance of the sequestration of glutathione in vacuoles under oxidative stress. PMID:22093747

The type III secretion system needle tip complex mediates host cell sensing and translocon insertion.

PubMed

Veenendaal, Andreas K J; Hodgkinson, Julie L; Schwarzer, Lynn; Stabat, David; Zenk, Sebastian F; Blocker, Ariel J

2007-03-01

Type III secretion systems (T3SSs) are essential virulence determinants of many Gram-negative bacterial pathogens. The Shigella T3SS consists of a cytoplasmic bulb, a transmembrane region and a hollow 'needle' protruding from the bacterial surface. Physical contact with host cells initiates secretion and leads to assembly of a pore, formed by IpaB and IpaC, in the host cell membrane, through which proteins that facilitate host cell invasion are translocated. As the needle is implicated in host cell sensing and secretion regulation, its tip should contain components that initiate host cell contact. Through biochemical and immunological studies of wild-type and mutant Shigella T3SS needles, we reveal tip complexes of differing compositions and functional states, which appear to represent the molecular events surrounding host cell sensing and pore formation. Our studies indicate that the interaction between IpaB and IpaD at needle tips is key to host cell sensing, orchestration of IpaC secretion and its subsequent assembly at needle tips. This allows insertion into the host cell membrane of a translocation pore that is continuous with the needle.

Generation of Stable Co-Cultures of Vascular Cells in a Honeycomb Alginate Scaffold

PubMed Central

Yamamoto, Masaya; James, Daylon; Li, Hui; Butler, Jason; Rafii, Shahin

2010-01-01

Scaffold-guided vascular tissue engineering has been investigated as a means to generate functional and transplantable vascular tissue grafts that increase the efficacy of cell-based therapeutic strategies in regenerative medicine. In this study, we employed confocal microscopy and three-dimensional reconstruction to assess the engraftment and growth potential of vascular cells within an alginate scaffold with aligned pores. We fabricated honeycomb alginate scaffolds with aligned pores, whose surface was immobilized with fibronectin and subsequently coated with matrigel. Endothelial cells were seeded into aligned pore scaffolds in the presence and absence of human smooth muscle cells. We showed that endothelial cells seeded into alginate scaffolds attach on the surface of aligned pores in vitro, giving rise to stable co-cultures of vascular cells. Moreover, the three-dimensional alginate depots containing the cells were exposed to laminar flow in order to recapitulate physiological shear stress found in the vasculature in vivo. After the flow exposure, the scaffold remained intact and some cells remained adherent to the scaffold and aligned in the flow direction. These studies demonstrate that alginate scaffolds provide a suitable matrix for establishing durable angiogenic modules that may ultimately enhance organ revascularization. PMID:19705957

Optimal Interval for Repeated Gastric Cancer Screening in Normal-Risk Healthy Korean Adults: A Retrospective Cohort Study

PubMed Central

Bae, Jong-Myon; Shin, Sang Yop; Kim, Eun Hee

2015-01-01

Purpose This retrospective cohort study was conducted to estimate the optimal interval for gastric cancer screening in Korean adults with initial negative screening results. Materials and Methods This study consisted of voluntary Korean screenees aged 40 to 69 years who underwent subsequent screening gastroscopies after testing negative in the baseline screening performed between January 2007 and December 2011. A new case was defined as the presence of gastric cancer cells in biopsy specimens obtained upon gastroscopy. The follow-up periods were calculated during the months between the date of baseline screening gastroscopy and positive findings upon subsequent screenings, stratified by sex and age group. The mean sojourn time (MST) for determining the screening interval was estimated using the prevalence/incidence ratio. Results Of the 293,520 voluntary screenees for the gastric cancer screening program, 91,850 (31.29%) underwent subsequent screening gastroscopies between January 2007 and December 2011. The MSTs in men and women were 21.67 months (95% confidence intervals [CI], 17.64 to 26.88 months) and 15.14 months (95% CI, 9.44 to 25.85 months), respectively. Conclusion These findings suggest that the optimal interval for subsequent gastric screening in both men and women is 24 months, supporting the 2-year interval recommended by the nationwide gastric cancer screening program. PMID:25687874

The protective effect of pentoxifylline versus silymarin on the pancreas through increasing adenosine by CD39 in a rat model of liver cirrhosis: Pharmacological, biochemical and histological study.

PubMed

Mohamed, Doaa I; Nabih, Enas S; El-Waseef, Dalia A A; El-Kharashi, Omnyah A; Abd El Samad, Abeer A

2018-04-20

Impaired glucose homoeostasis due to insulin resistance and decrease sensitivity of pancreatic β-cells is a feature of liver disease and results into hepatogenous diabetes. Decrease expression of CD39 was linked to inflammation and occurrence of diabetes. Therefore, we performed this study to explore the protective effect of pentoxifylline (PTX) and silymarin administration on the β-cells of the pancreas in a rat model of thioacetamide induced liver cirrhosis. Biochemical, histological and immunohistochemistry studies of the liver and pancreas were performed and provided an evidence on the protective effect of PTX to pancreatic β-cells compared to silymarin. Also, silymarin induced a significant improvement of liver cirrhosis compared to PTX. In conclusion, the potential protective effect of PTX against β-cells deterioration could be attributed to increasing pancreatic CD39 expression and the subsequent increase of adenosine. Copyright © 2018 Elsevier B.V. All rights reserved.

Epithelial-to-mesenchymal transition leads to disease-stage differences in circulating tumor cell detection and metastasis in pre-clinical models of prostate cancer.

PubMed

Lowes, Lori E; Goodale, David; Xia, Ying; Postenka, Carl; Piaseczny, Matthew M; Paczkowski, Freeman; Allan, Alison L

2016-11-15

Metastasis is the cause of most prostate cancer (PCa) deaths and has been associated with circulating tumor cells (CTCs). The presence of ≥5 CTCs/7.5mL of blood is a poor prognosis indicator in metastatic PCa when assessed by the CellSearch® system, the "gold standard" clinical platform. However, ~35% of metastatic PCa patients assessed by CellSearch® have undetectable CTCs. We hypothesize that this is due to epithelial-to-mesenchymal transition (EMT) and subsequent loss of necessary CTC detection markers, with important implications for PCa metastasis. Two pre-clinical assays were developed to assess human CTCs in xenograft models; one comparable to CellSearch® (EpCAM-based) and one detecting CTCs semi-independent of EMT status via combined staining with EpCAM/HLA (human leukocyte antigen). In vivo differences in CTC generation, kinetics, metastasis and EMT status were determined using 4 PCa models with progressive epithelial (LNCaP, LNCaP-C42B) to mesenchymal (PC-3, PC-3M) phenotypes. Assay validation demonstrated that the CellSearch®-based assay failed to detect a significant number (~40-50%) of mesenchymal CTCs. In vivo, PCa with an increasingly mesenchymal phenotype shed greater numbers of CTCs more quickly and with greater metastatic capacity than PCa with an epithelial phenotype. Notably, the CellSearch®-based assay captured the majority of CTCs shed during early-stage disease in vivo, and only after establishment of metastases were a significant number of undetectable CTCs present. This study provides important insight into the influence of EMT on CTC generation and subsequent metastasis, and highlights that novel technologies aimed at capturing mesenchymal CTCs may only be useful in the setting of advanced metastatic disease.

New insight into the disinfection mechanism of Fusarium monoliforme and Aspergillus niger by TiO2 photocatalyst under low intensity UVA light.

PubMed

Pokhum, Chonlada; Viboonratanasri, Duangamon; Chawengkijwanich, Chamorn

2017-11-01

Titanium dioxide (TiO 2) photocatalytic reaction has great potential for the disinfection of harmful pathogens. However, the disinfection mechanisms of TiO 2 photocatalysis are not yet well-known for fungi and protozoa. In this work, the photocatalytic disinfection mechanism of Fusarium monoliforme and Aspergillus niger under low intensity UVA light (365nm, <10W/m 2 ) was studied at the ultrastructural level. Photocatalytic treatments showed that the photocatalytic oxidation of 10% TiO 2 based paint was efficacious in the complete disinfection of F. monoliforme under low intensity UVA light. No growth of F. monoliforme was observed on agar plate in the subsequent dark. Transmission electron microscopy (TEM) of F. monoliforme exposed to TiO 2 photocatalysis treatment showed a distinct damage to electron-dense outer cell wall, but not to an underlying electron-transparent layer cell wall. The TEM image revealed that the UVA-light only did not damage cell wall, cell membrane and cellular organelles. Unlike, A. niger was more sensitive to UVA-light. Serious destructions of cell membrane and cellular organelles were shown in A. niger exposed to UVA-light only and photocatalytic treatments. However, morphological change in A. niger cell wall was only observed in photocatalytic treatment. Changes to the outermost melanin like layer and cell wall of A. niger spore due to photocatalytic treatment were greatly apparent while the intracellular organelles of A. niger spore were not affected. Therefore, regrowth of A. niger on agar plate was expected from the germination of A. niger spore in the subsequent dark. These observations give a better understanding of the photocatalytic disinfection mechanism toward fungi. Copyright © 2017 Elsevier B.V. All rights reserved.

Macrophages clear refrigerator storage-damaged red blood cells and subsequently secrete cytokines in vivo, but not in vitro, in a murine model.

PubMed

Wojczyk, Boguslaw S; Kim, Nina; Bandyopadhyay, Sheila; Francis, Richard O; Zimring, James C; Hod, Eldad A; Spitalnik, Steven L

2014-12-01

In mice, refrigerator-stored red blood cells (RBCs) are cleared by extravascular hemolysis and induce cytokine production. To enhance understanding of this phenomenon, we sought to model it in vitro. Ingestion of refrigerator-stored murine RBCs and subsequent cytokine production were studied using J774A.1 mouse macrophage cells and primary murine splenic macrophages. Wild-type and Ccl2-GFP reporter mice were used for RBC clearance in vivo. Although J774A.1 cells and primary macrophages preferentially ingested refrigerator-stored RBCs in vitro, compared to freshly isolated RBCs, neither produced increased cytokines after erythrophagocytosis. In contrast, phagocytosis of refrigerator-stored RBCs in vivo induced increases in circulating monocyte chemoattractant protein-1 (MCP-1) and keratinocyte chemoattractant (KC) and correspondingly increased mRNA levels in mouse spleen and liver. In the spleen, these were predominantly expressed by CD11b+ cells. Using Ccl2-GFP reporter mice, the predominant splenic population responsible for MCP-1 mRNA production was tissue-resident macrophages (i.e., CD45+, CD11b+, F4/80+, Ly6c+, and CD11c(low) cells). J774A.1 cells and primary macrophages selectively ingested refrigerator-stored RBCs by phagocytosis. Although cytokine expression was not enhanced, this approach could be used to identify the relevant receptor-ligand combination(s). In contrast, cytokine levels increased after phagocytosis of refrigerator-stored RBCs in vivo. These were primarily cleared in the liver and spleen, which demonstrated increased MCP-1 and KC mRNA expression. Finally, in mouse spleen, tissue-resident macrophages were predominantly involved in MCP-1 mRNA production. The differences between cytokine production in vitro and in vivo are not yet well understood. © 2014 AABB.

Culture supernatants of oral cancer cells induce impaired IFN-α production of pDCs partly through the down-regulation of TLR-9 expression.

PubMed

Han, Nannan; Zhang, Zun; Jv, Houyu; Hu, Jingzhou; Ruan, Min; Zhang, Chenping

2018-06-05

The aim of the present study was to investigate whether tumor-derived supernatants down-regulate the immune function of plasmacytoid dendritic cells (pDCs) in oral cancer and the potential molecular mechanisms of this effect. Immunohistochemistry (IHC) and flow cytometry were used to detect tumor-infiltrating and peripheral blood pDCs. MTS and flow cytometry were employed to evaluate the immune response of CD4 + T cells. Real-time PCR and ELISA assays were used to identify TLR-7 and TLR-9 expression, IFN-α production and tumor-secreted soluble cytokines. The proportion of pDCs (0.121%±0.043%) was significantly higher in Oral squamous cell carcinoma (OSCC) samples than in normal tissue (0.023%±0.016%) (P = 0.021). TLR9 mRNA was significantly lower in tumor-infiltrating pDCs and positively correlated to low IFN-α production (r = 0.956; P<0.01). The supernatant of oral cancer cells negatively regulated TLR9 mRNA expression and the subsequent IFN-α production of pDCs, which inhibited the immune response of CD4 + T cells. The neutralizing antibodies blocking assay showed that the specific inhibitory effect of pDC functionality was associated with the soluble fraction of the oral cancer environment, which is mainly mediated by IL-10 and TGF-β cooperation. Tumor-derived supernatants may impair the function of tumor-infiltrating pDCs, which subsequently decreases the immune response of CD4 + T cells in human oral cancer through TGF-β- and IL-10- dependent mechanisms. Careful manipulation of these impaired pDCs may help develop an important alternative immunotherapy for the treatment of oral cancer. Copyright © 2018 Elsevier Ltd. All rights reserved.

Modulation of Mitochondrial DNA Copy Number to Induce Hepatocytic Differentiation of Human Amniotic Epithelial Cells.

PubMed

Vaghjiani, Vijesh; Cain, Jason E; Lee, William; Vaithilingam, Vijayaganapathy; Tuch, Bernard E; St John, Justin C

2017-10-15

Mitochondrial deoxyribonucleic acid (mtDNA) copy number is tightly regulated during pluripotency and differentiation. There is increased demand of cellular adenosine triphosphate (ATP) during differentiation for energy-intensive cell types such as hepatocytes and neurons to meet the cell's functional requirements. During hepatocyte differentiation, mtDNA copy number should be synchronously increased to generate sufficient ATP through oxidative phosphorylation. Unlike bone marrow mesenchymal cells, mtDNA copy number failed to increase by 28 days of differentiation of human amniotic epithelial cells (hAEC) into hepatocyte-like cells (HLC) despite their expression of some end-stage hepatic markers. This was due to higher levels of DNA methylation at exon 2 of POLGA, the mtDNA-specific replication factor. Treatment with a DNA demethylation agent, 5-azacytidine, resulted in increased mtDNA copy number, reduced DNA methylation at exon 2 of POLGA, and reduced hepatic gene expression. Depletion of mtDNA followed by subsequent differentiation did not increase mtDNA copy number, but reduced DNA methylation at exon 2 of POLGA and increased expression of hepatic and pluripotency genes. We encapsulated hAEC in barium alginate microcapsules and subsequently differentiated them into HLC. Encapsulation resulted in no net increase of mtDNA copy number but a significant reduction in DNA methylation of POLGA. RNAseq analysis showed that differentiated HLC express hepatocyte-specific genes but also increased expression of inflammatory interferon genes. Differentiation in encapsulated cells showed suppression of inflammatory genes as well as increased expression of genes associated with hepatocyte function pathways and networks. This study demonstrates that an increase in classical hepatic gene expression can be achieved in HLC through encapsulation, although they fail to effectively regulate mtDNA copy number.

Human CD3+ T-Cells with the Anti-ERBB2 Chimeric Antigen Receptor Exhibit Efficient Targeting and Induce Apoptosis in ERBB2 Overexpressing Breast Cancer Cells

PubMed Central

Munisvaradass, Rusheni; Kumar, Suresh; Govindasamy, Chandramohan; Alnumair, Khalid S.; Mok, Pooi Ling

2017-01-01

Breast cancer is a common malignancy among women. The innate and adaptive immune responses failed to be activated owing to immune modulation in the tumour microenvironment. Decades of scientific study links the overexpression of human epidermal growth factor receptor 2 (ERBB2) antigen with aggressive tumours. The Chimeric Antigen Receptor (CAR) coding for specific tumour-associated antigens could initiate intrinsic T-cell signalling, inducing T-cell activation, and cytotoxic activity without the need for major histocompatibility complex recognition. This renders CAR as a potentially universal immunotherapeutic option. Herein, we aimed to establish CAR in CD3+ T-cells, isolated from human peripheral blood mononucleated cells that could subsequently target and induce apoptosis in the ERBB2 overexpressing human breast cancer cell line, SKBR3. Constructed CAR was inserted into a lentiviral plasmid containing a green fluorescent protein tag and produced as lentiviral particles that were used to transduce activated T-cells. Transduced CAR-T cells were then primed with SKBR3 cells to evaluate their functionality. Results showed increased apoptosis in SKBR3 cells co-cultured with CAR-T cells compared to the control (non–transduced T-cells). This study demonstrates that CAR introduction helps overcome the innate limitations of native T-cells leading to cancer cell apoptosis. We recommend future studies should focus on in vivo cytotoxicity of CAR-T cells against ERBB2 expressing tumours. PMID:28885562

Human CD3+ T-Cells with the Anti-ERBB2 Chimeric Antigen Receptor Exhibit Efficient Targeting and Induce Apoptosis in ERBB2 Overexpressing Breast Cancer Cells.

PubMed

Munisvaradass, Rusheni; Kumar, Suresh; Govindasamy, Chandramohan; Alnumair, Khalid S; Mok, Pooi Ling

2017-09-08

Breast cancer is a common malignancy among women. The innate and adaptive immune responses failed to be activated owing to immune modulation in the tumour microenvironment. Decades of scientific study links the overexpression of human epidermal growth factor receptor 2 (ERBB2) antigen with aggressive tumours. The Chimeric Antigen Receptor (CAR) coding for specific tumour-associated antigens could initiate intrinsic T-cell signalling, inducing T-cell activation, and cytotoxic activity without the need for major histocompatibility complex recognition. This renders CAR as a potentially universal immunotherapeutic option. Herein, we aimed to establish CAR in CD3+ T-cells, isolated from human peripheral blood mononucleated cells that could subsequently target and induce apoptosis in the ERBB2 overexpressing human breast cancer cell line, SKBR3. Constructed CAR was inserted into a lentiviral plasmid containing a green fluorescent protein tag and produced as lentiviral particles that were used to transduce activated T-cells. Transduced CAR-T cells were then primed with SKBR3 cells to evaluate their functionality. Results showed increased apoptosis in SKBR3 cells co-cultured with CAR-T cells compared to the control (non-transduced T-cells). This study demonstrates that CAR introduction helps overcome the innate limitations of native T-cells leading to cancer cell apoptosis. We recommend future studies should focus on in vivo cytotoxicity of CAR-T cells against ERBB2 expressing tumours.

POPISK: T-cell reactivity prediction using support vector machines and string kernels

PubMed Central

2011-01-01

Background Accurate prediction of peptide immunogenicity and characterization of relation between peptide sequences and peptide immunogenicity will be greatly helpful for vaccine designs and understanding of the immune system. In contrast to the prediction of antigen processing and presentation pathway, the prediction of subsequent T-cell reactivity is a much harder topic. Previous studies of identifying T-cell receptor (TCR) recognition positions were based on small-scale analyses using only a few peptides and concluded different recognition positions such as positions 4, 6 and 8 of peptides with length 9. Large-scale analyses are necessary to better characterize the effect of peptide sequence variations on T-cell reactivity and design predictors of a peptide's T-cell reactivity (and thus immunogenicity). The identification and characterization of important positions influencing T-cell reactivity will provide insights into the underlying mechanism of immunogenicity. Results This work establishes a large dataset by collecting immunogenicity data from three major immunology databases. In order to consider the effect of MHC restriction, peptides are classified by their associated MHC alleles. Subsequently, a computational method (named POPISK) using support vector machine with a weighted degree string kernel is proposed to predict T-cell reactivity and identify important recognition positions. POPISK yields a mean 10-fold cross-validation accuracy of 68% in predicting T-cell reactivity of HLA-A2-binding peptides. POPISK is capable of predicting immunogenicity with scores that can also correctly predict the change in T-cell reactivity related to point mutations in epitopes reported in previous studies using crystal structures. Thorough analyses of the prediction results identify the important positions 4, 6, 8 and 9, and yield insights into the molecular basis for TCR recognition. Finally, we relate this finding to physicochemical properties and structural features of the MHC-peptide-TCR interaction. Conclusions A computational method POPISK is proposed to predict immunogenicity with scores which are useful for predicting immunogenicity changes made by single-residue modifications. The web server of POPISK is freely available at http://iclab.life.nctu.edu.tw/POPISK. PMID:22085524

POPISK: T-cell reactivity prediction using support vector machines and string kernels.

PubMed

Tung, Chun-Wei; Ziehm, Matthias; Kämper, Andreas; Kohlbacher, Oliver; Ho, Shinn-Ying

2011-11-15

Accurate prediction of peptide immunogenicity and characterization of relation between peptide sequences and peptide immunogenicity will be greatly helpful for vaccine designs and understanding of the immune system. In contrast to the prediction of antigen processing and presentation pathway, the prediction of subsequent T-cell reactivity is a much harder topic. Previous studies of identifying T-cell receptor (TCR) recognition positions were based on small-scale analyses using only a few peptides and concluded different recognition positions such as positions 4, 6 and 8 of peptides with length 9. Large-scale analyses are necessary to better characterize the effect of peptide sequence variations on T-cell reactivity and design predictors of a peptide's T-cell reactivity (and thus immunogenicity). The identification and characterization of important positions influencing T-cell reactivity will provide insights into the underlying mechanism of immunogenicity. This work establishes a large dataset by collecting immunogenicity data from three major immunology databases. In order to consider the effect of MHC restriction, peptides are classified by their associated MHC alleles. Subsequently, a computational method (named POPISK) using support vector machine with a weighted degree string kernel is proposed to predict T-cell reactivity and identify important recognition positions. POPISK yields a mean 10-fold cross-validation accuracy of 68% in predicting T-cell reactivity of HLA-A2-binding peptides. POPISK is capable of predicting immunogenicity with scores that can also correctly predict the change in T-cell reactivity related to point mutations in epitopes reported in previous studies using crystal structures. Thorough analyses of the prediction results identify the important positions 4, 6, 8 and 9, and yield insights into the molecular basis for TCR recognition. Finally, we relate this finding to physicochemical properties and structural features of the MHC-peptide-TCR interaction. A computational method POPISK is proposed to predict immunogenicity with scores which are useful for predicting immunogenicity changes made by single-residue modifications. The web server of POPISK is freely available at http://iclab.life.nctu.edu.tw/POPISK.

[A case of cytology-positive, stage IV gastric cancer, alive with no recurrence for 4 years, curatively treated with combination chemotherapy using S-1, CPT-11 and subsequent total gastrectomy].

PubMed

Kubo, Naoshi; Nobuhara, Yasuyuki; Kanemura, Mizuyuki; Sunami, Takeshi; Nishimura, Shigehiko; Ako, Eiji; Yo, Taiho

2007-11-01

A 68-year-old man was admitted to another hospital because of progressive weight decrease and appetite loss. Endoscopic examination revealed type 4 advanced gastric cancer at the upper body of the stomach. In February, 2003, he patient had probe laparotomy because there was a small amount of ascites in his peritoneal cavity, and intraoperative washing cytology revealed cancer cells in ascites.Subsequently, we started chemotherapy using S-1 and CPT-11. S-1 at a dose of 100 mg/day was orally administered for 2 weeks, and CPT-11 at a dose of 90 mg/body was intravenously administered once a week for 2 weeks followed by a 2-week drug-free period as 1 course. After 7 courses of the chemotherapy, the main lesion endoscopically vanished.Subsequently, the patient underwent curative total gastrectomy together with D2 lymph node dissection. Intraoperative cytology revealed no cancer cells, and histological examination of the primary lesion showed cancer cells invading the subserosa with no metastasis to any dissected lymph nodes. This therapy induced Grade 2 effect on cancer cells.Postoperatively, only S-1 was administered to the patient, who has remained alive with no recurrence for 4 years as of January, 2007.

Visualization of IAV Genomes at the Single-Cell Level.

PubMed

Wang, Dan; Ma, Wenjun

2017-10-01

Different influenza A viruses (IAVs) infect the same cell in a host, and can subsequently produce new viruses through genome reassortment. By combining padlock probe RNA labeling with a single-cell analysis, a new approach effectively captures IAV genome trafficking and defines a time window for genome reassortment from same-cell coinfections. Copyright © 2017 Elsevier Ltd. All rights reserved.

Incorporation of ophiobolin a into novel chemoembolization particles for cancer cell treatment.

PubMed

Morrison, Rachel; Gardiner, Chris; Evidente, Antonio; Kiss, Robert; Townley, Helen

2014-10-01

To design and synthesize chemoembolization particles for the delivery of Ophiobolin A (OphA), a promising fungal-derived chemotherapeutic, directly at the tumour location. To investigate cell death mechanism of OphA on a Rhabdomyosarcoma cancer (RD) cell line. Rhabdomyosarcoma is the most common soft tissue sarcoma in children; with a 5-year survival rate of between 30 and 65%. Multimodal chemoembolization particles were prepared by sintering mesoporous silica nanoparticles, prepared by the sol-gel method, onto the surface of polystyrene microspheres, prepared by suspension copolymerisation. The chemoembolization particles were subsequently loaded with OphA. The effects of OphA in vitro were characterised by flow cytometry and nanoparticle tracking analysis (NanoSight). High loading of OphA onto the chemoembolization particles was achieved. The subsequent release of OphA onto RD cells in culture showed a 70% reduction in cell viability. OphA caused RD cells to round up and their membrane to bleb and caused cell death via apoptosis. OphA caused both an increase in the number of microvesicles produced and an increase in DNA content within these microvesicles. The prepared chemoembolization particles showed good efficacy against RD cells in culture.

B cell activation. III. B cell plasma membrane depolarization and hyper- Ia antigen expression induced by receptor immunoglobulin cross-linking are coupled

PubMed Central

1983-01-01

We report investigation of the relationship between ligand-induced B cell plasma membrane depolarization and increased expression of membrane-associated, I-A subregion encoded (mI-A) antigens. Results demonstrate that equal frequencies of B cells are stimulated to undergo membrane depolarization and to increase mI-A expression in response to mitogen, anti-Ig, and thymus-independent (TI) or thymus-dependent (TD) antigens. Further, a cause-and-effect relationship between these two events is suggested by results that demonstrate that inhibition of anti- Fab--induced depolarization by valinomycin also inhibits the subsequent increase in mI-A antigen expression and "passive" (non-ligand-mediated) depolarization of murine B cells by K+ results in hyper-mI-A antigen expression. Based upon these results we hypothesize that antigen- mediated receptor cross-linking results in signal transduction via membrane depolarization, which is resultant in increased mI-A antigen synthesis and cell surface expression. This increase in mI-A antigen density may render the B cell more receptive to subsequent interaction with I-region-restricted helper T cells. PMID:6415207

Phenotypic characterization of collagen gel embedded primary human breast epithelial cells in athymic nude mice.

PubMed

Yang, J; Guzman, R C; Popnikolov, N; Bandyopadhyay, G K; Christov, K; Collins, G; Nandi, S

1994-06-30

We have developed a method to characterize the phenotypes and tumorigenicity of dissociated human breast epithelial cells. The dissociated cells were first embedded in collagen gels and subsequently transplanted subcutaneously in vivo in athymic nude mice. The transplantation of dissociated epithelial cells from reduction mammoplasties, presumed to be normal, always resulted in normal histomorphology. Epithelial cells were arranged as short tubular structures consisting of lumina surrounded by epithelial cells with an occasional more complex branching structure. These outgrowths were surrounded by intact basement membrane and were embedded in collagen gel that, at termination, contained collagenous stroma with fibroblasts and blood vessels. In contrast, transplantation of dissociated breast epithelial cells from breast cancer specimens resulted in outgrowths with an invasive pattern infiltrating the collagen gel as well as frank invasion into vascular space, nerves and muscles. These observations were made long before the subsequent palpable stage which resulted if left in the mouse for a long enough time. The dissociated human breast epithelial cells thus retained their intrinsic property to undergo morphogenesis to reflect their original phenotype when placed in a suitable environment, the collagen gel.

The Biodistribution and Immune Suppressive Effects of Breast Cancer-Derived Exosomes.

PubMed

Wen, Shu Wen; Sceneay, Jaclyn; Lima, Luize Goncalves; Wong, Christina S F; Becker, Melanie; Krumeich, Sophie; Lobb, Richard J; Castillo, Vanessa; Wong, Ke Ni; Ellis, Sarah; Parker, Belinda S; Möller, Andreas

2016-12-01

Small membranous secretions from tumor cells, termed exosomes, contribute significantly to intercellular communication and subsequent reprogramming of the tumor microenvironment. Here, we use optical imaging to determine that exogenously administered fluorescently labeled exosomes derived from highly metastatic murine breast cancer cells distributed predominantly to the lung of syngeneic mice, a frequent site of breast cancer metastasis. At the sites of accumulation, exosomes were taken up by CD45 + bone marrow-derived cells. Subsequent long-term conditioning of naïve mice with exosomes from highly metastatic breast cancer cells revealed the accumulation of myeloid-derived suppressor cells in the lung and liver. This favorable immune suppressive microenvironment was capable of promoting metastatic colonization in the lung and liver, an effect not observed from exosomes derived from nonmetastatic cells and liposome control vesicles. Furthermore, we determined that breast cancer exosomes directly suppressed T-cell proliferation and inhibited NK cell cytotoxicity, and hence likely suppressed the anticancer immune response in premetastatic organs. Together, our findings provide novel insight into the tissue-specific outcomes of breast cancer-derived exosome accumulation and their contribution to immune suppression and promotion of metastases. Cancer Res; 76(23); 6816-27. ©2016 AACR. ©2016 American Association for Cancer Research.

Microarrays for the evaluation of cell-biomaterial surface interactions

NASA Astrophysics Data System (ADS)

Thissen, H.; Johnson, G.; McFarland, G.; Verbiest, B. C. H.; Gengenbach, T.; Voelcker, N. H.

2007-01-01

The evaluation of cell-material surface interactions is important for the design of novel biomaterials which are used in a variety of biomedical applications. While traditional in vitro test methods have routinely used samples of relatively large size, microarrays representing different biomaterials offer many advantages, including high throughput and reduced sample handling. Here, we describe the simultaneous cell-based testing of matrices of polymeric biomaterials, arrayed on glass slides with a low cell-attachment background coating. Arrays were constructed using a microarray robot at 6 fold redundancy with solid pins having a diameter of 375 μm. Printed solutions contained at least one monomer, an initiator and a bifunctional crosslinker. After subsequent UV polymerisation, the arrays were washed and characterised by X-ray photoelectron spectroscopy. Cell culture experiments were carried out over 24 hours using HeLa cells. After labelling with CellTracker ® Green for the final hour of incubation and subsequent fixation, the arrays were scanned. In addition, individual spots were also viewed by fluorescence microscopy. The evaluation of cell-surface interactions in high-throughput assays as demonstrated here is a key enabling technology for the effective development of future biomaterials.

Syringe needle skull penetration reduces brain injuries and secondary inflammation following intracerebral neural stem cell transplantation.

PubMed

Gao, Mou; Dong, Qin; Zhang, Hongtian; Yang, Yang; Zhu, Jianwei; Yang, Zhijun; Xu, Minhui; Xu, Ruxiang

2017-03-01

Intracerebral neural stem cell (NSC) transplantation is beneficial for delivering stem cell grafts effectively, however, this approach may subsequently result in brain injury and secondary inflammation. To reduce the risk of promoting brain injury and secondary inflammation, two methods were compared in the present study. Murine skulls were penetrated using a drill on the left side and a syringe needle on the right. Mice were randomly divided into three groups (n=84/group): Group A, receiving NSCs in the left hemisphere and PBS in the right; group B, receiving NSCs in the right hemisphere and PBS in the left; and group C, receiving equal NSCs in both hemispheres. Murine brains were stained for morphological analysis and subsequent evaluation of infiltrated immune cells. ELISA was performed to detect neurotrophic and immunomodulatory factors in the brain. The findings indicated that brain injury and secondary inflammation in the left hemisphere were more severe than those in the right hemisphere, following NSC transplantation. In contrast to the left hemisphere, more neurotrophic factors but less pro-inflammatory cytokines were detected in the right hemisphere. In addition, increased levels of neurotrophic factors and interleukin (IL)-10 were observed in the NSC transplantation side when compared with the PBS-treated hemispheres, although lower levels of IL-6 and tumor necrosis factor-α were detected. In conclusion, the present study indicated that syringe needle skull penetration vs. drill penetration is an improved method that reduces the risk of brain injury and secondary inflammation following intracerebral NSC transplantation. Furthermore, NSCs have the potential to modulate inflammation secondary to brain injuries.

Syk-mediated tyrosine phosphorylation of mule promotes TNF-induced JNK activation and cell death.

PubMed

Lee, C K; Yang, Y; Chen, C; Liu, J

2016-04-14

The transcription factor Miz1 negatively regulates TNF-induced JNK activation and cell death by suppressing TRAF2 K63-polyubiquitination; upon TNF stimulation, the suppression is relieved by Mule/ARF-BP1-mediated Miz1 ubiquitination and subsequent degradation. It is not known how Mule is activated by TNF. Here we report that TNF activates Mule by inducing the dissociation of Mule from its inhibitor ARF. ARF binds to and thereby inhibits the E3 ligase activity of Mule in the steady state. TNF induces tyrosine phosphorylation of Mule, which subsequently dissociates from ARF and becomes activated. Inhibition of Mule phosphorylation by silencing of the Spleen Tyrosine Kinase (Syk) prevents its dissociation from ARF, thereby inhibiting Mule E3 ligase activity and TNF-induced JNK activation and cell death. Our data provides a missing link in TNF signaling pathway that leads to JNK activation and cell death.

Reporter-Based Isolation of Developmental Myogenic Progenitors

PubMed Central

Kheir, Eyemen; Cusella, Gabriella; Messina, Graziella; Cossu, Giulio; Biressi, Stefano

2018-01-01

The formation and activity of mammalian tissues entail finely regulated processes, involving the concerted organization and interaction of multiple cell types. In recent years the prospective isolation of distinct progenitor and stem cell populations has become a powerful tool in the hands of developmental biologists and has rendered the investigation of their intrinsic properties possible. In this protocol, we describe how to purify progenitors with different lineage history and degree of differentiation from embryonic and fetal skeletal muscle by fluorescence-activated cell sorting (FACS). The approach takes advantage of a panel of murine strains expressing fluorescent reporter genes specifically in the myogenic progenitors. We provide a detailed description of the dissection procedures and of the enzymatic dissociation required to maximize the yield of mononucleated cells for subsequent FACS-based purification. The procedure takes ~6–7 h to complete and allows for the isolation and the subsequent molecular and phenotypic characterization of developmental myogenic progenitors. PMID:29674978

Tgf-beta induced Erk phosphorylation of smad linker region regulates smad signaling.

PubMed

Hough, Chris; Radu, Maria; Doré, Jules J E

2012-01-01

The Transforming Growth Factor-Beta (TGF-β) family is involved in regulating a variety of cellular processes such as apoptosis, differentiation, and proliferation. TGF-β binding to a Serine/Threonine kinase receptor complex causes the recruitment and subsequent activation of transcription factors known as smad2 and smad3. These proteins subsequently translocate into the nucleus to negatively or positively regulate gene expression. In this study, we define a second signaling pathway leading to TGF-β receptor activation of Extracellular Signal Regulated Kinase (Erk) in a cell-type dependent manner. TGF-β induced Erk activation was found in phenotypically normal mesenchymal cells, but not normal epithelial cells. By activating phosphotidylinositol 3-kinase (PI3K), TGF-β stimulates p21-activated kinase2 (Pak2) to phosphorylate c-Raf, ultimately resulting in Erk activation. Activation of Erk was necessary for TGF-β induced fibroblast replication. In addition, Erk phosphorylated the linker region of nuclear localized smads, resulting in increased half-life of C-terminal phospho-smad 2 and 3 and increased duration of smad target gene transcription. Together, these data show that in mesenchymal cell types the TGF-β/PI3K/Pak2/Raf/MEK/Erk pathway regulates smad signaling, is critical for TGF-β-induced growth and is part of an integrated signaling web containing multiple interacting pathways rather than discrete smad/non-smad pathways.

Intratumoral delivery of low doses of anti-CD40 mAb combined with monophosphoryl lipid A induces local and systemic antitumor effects in immunocompetent and T cell-deficient mice

PubMed Central

Van De Voort, Tyler J.; Felder, Mildred A. R.; Yang, Richard K.; Sondel, Paul M.; Rakhmilevich, Alexander L.

2012-01-01

In this study, an agonistic anti-CD40 monoclonal antibody was combined with monophosphoryl lipid A (MPL), a nontoxic derivative of LPS and agonist of toll-like receptor 4, to assess the immunomodulatory and antitumor synergy between the two agents in mice. Anti-CD40 was capable of priming macrophages to subsequent ex vivo activation by MPL in immunocompetent and T cell-depleted mice. Intraperitoneal injections of anti-CD40+MPL induced additive to synergistic suppression of poorly immunogenic B16-F10 melanoma growing subcutaneously in syngeneic mice. When anti-CD40+MPL were injected directly into the subcutaneous tumor, the combination treatment was more effective, even with a 25-fold reduction in dose. Low-dose intratumoral treatment also slowed the growth of a secondary tumor growing simultaneously at a distant, untreated site. Antitumor effects were also induced in immunodeficient SCID mice and in T cell-depleted C57BL/6 mice. Taken together, our results show that the antitumor effects of anti-CD40 are enhanced by subsequent treatment with MPL, even in T cell-deficient hosts. These preclinical data suggest that an anti-CD40+MPL combined regimen is appropriate for clinical testing in human patients, including cancer patients that may be immunosuppressed from prior chemotherapy. PMID:23211623

Clinical heterogeneity of diffuse large B cell lymphoma following failure of front-line immunochemotherapy.

PubMed

Farooq, Umar; Maurer, Matthew J; Thompson, Carrie A; Thanarajasingam, Gita; Inwards, David J; Micallef, Ivana; Macon, William; Syrbu, Sergei; Lin, Tasha; Lin, Yi; Ansell, Stephen M; Nowakowski, Grzegorz S; Habermann, Thomas M; Cerhan, James R; Link, Brian K

2017-10-01

This study aimed to describe the patterns of care and outcomes of diffuse large B cell lymphoma (DLBCL) after failure of front line anthracycline-based immunochemotherapy (IC). Patients with newly diagnosed lymphoma were prospectively enrolled in Molecular Epidemiology Resource (MER) of the University of Iowa/Mayo Clinic Lymphoma Specialized Program of Research Excellzence. All DLBCL and primary mediastinal B-cell lymphoma (PMBL) patients treated with front-line anthracycline-based IC were followed for relapse. Patients with relapse on follow-up and subsequently retreated were included in this analysis. 1039 patients received anthracycline-based IC between 2002 and 2012, of which 244 relapsed and were subsequently retreated. Across all therapies, overall survival at 4 years (OS4) from relapse was 28% and 103 patients ultimately underwent autologous haematopoietic cell transplant (autoHCT) with OS4 from autoHCT of 51%. Patients relapsing after 12 months from initial diagnosis had OS4 of 47% but those with a transient or no response to initial therapy had OS4 of only 13%. Outcomes of relapsed or refractory DLBCL differ substantially when categorized by response to initial therapy, timing of relapse and opportunity to undergo autoHCT. The design and interpretation of uncontrolled trials should account for this heterogeneity in patients with relapsed DLBCL. © 2017 John Wiley & Sons Ltd.

Molecular profiling of tumor progression in head and neck cancer.

PubMed

Belbin, Thomas J; Singh, Bhuvanesh; Smith, Richard V; Socci, Nicholas D; Wreesmann, Volkert B; Sanchez-Carbayo, Marta; Masterson, Jessica; Patel, Snehal; Cordon-Cardo, Carlos; Prystowsky, Michael B; Childs, Geoffrey

2005-01-01

To assess gene expression changes associated with tumor progression in patients with squamous cell carcinoma of the oral cavity. A microarray containing 17 840 complementary DNA clones was used to measure gene expression changes associated with tumor progression in 9 patients with squamous cell carcinoma of the oral cavity. Samples were taken for analysis from the primary tumor, nodal metastasis, and "normal" mucosa from the patients' oral cavity. Tertiary care facility. Patients Nine patients with stage III or stage IV untreated oral cavity squamous cell carcinoma. Our analysis to categorize genes based on their expression patterns has identified 140 genes that consistently increased in expression during progression from normal tissue to invasive tumor and subsequently to metastatic node (in at least 4 of the 9 cases studied). A similar list of 94 genes has been identified that decreased in expression during tumor progression and metastasis. We validated this gene discovery approach by selecting moesin (a member of the ezrin/radixin/moesin [ERM] family of cytoskeletal proteins) and one of the genes that consistently increased in expression during tumor progression for subsequent immunohistochemical analysis using a head and neck squamous cell carcinoma tissue array. A distinct pattern of gene expression, with progressive up- or down-regulation of expression, is found during the progression from histologically normal tissue to primary carcinoma and to nodal metastasis.

Induction of keratinocyte migration by ECa 233 is mediated through FAK/Akt, ERK, and p38 MAPK signaling.

PubMed

Singkhorn, Sawana; Tantisira, Mayuree H; Tanasawet, Supita; Hutamekalin, Pilaiwanwadee; Wongtawatchai, Tulaporn; Sukketsiri, Wanida

2018-03-13

Centella asiatica is widely considered the most important medicinal plant for treating and relieving skin diseases. Recently developed standardized extract of Centella asiatica ECa 233 has demonstrated positive effects on wound healing of incision and burn wound in rats. However, knowledge associated with wound healing mechanism of ECa 233 was scare. Therefore, this study aimed to investigate the effect and underlying molecular mechanisms of ECa 233 on the migration of a human keratinocyte cell line (HaCaT) using scratch wound healing assay. Formation of filopodia, a key protein in cell migration as well as signaling pathways possibly involved were subsequently assessed. It was found that HaCaT cell migration was significantly enhanced by ECa 233 in a concentration- and time-dependent manner. The filopodia formations were accordingly increased in exposure to ECa 233 at concentrations of 0.1-100 μg/ml. Furthermore, ECa 233 was found to significantly upregulate the expression of Rac1 and RhoA and to induce phosphorylation of FAK and Akt as well as ERK and p38 MAPK. Taken all together, it is suggestive that ECa 233 induces cell migration and subsequently promotes wound healing activity, through the activation of FAK, Akt, and MAPK signaling pathways thereby supporting the role of ECa 233 to be further developed for the clinical treatment of wound. Copyright © 2018 John Wiley & Sons, Ltd.

Culture of preimplantation mouse embryos affects fetal development and the expression of imprinted genes.

PubMed

Khosla, S; Dean, W; Brown, D; Reik, W; Feil, R

2001-03-01

Culture of preimplantation mammalian embryos and cells can influence their subsequent growth and differentiation. Previously, we reported that culture of mouse embryonic stem cells is associated with deregulation of genomic imprinting and affects the potential for these cells to develop into normal fetuses. The purpose of our current study was to determine whether culture of preimplantation mouse embryos in a chemically defined medium (M16) with or without fetal calf serum (FCS) can affect their subsequent development and imprinted gene expression. Only one third of the blastocysts that had been cultured from two-cell embryos in M16 medium complemented with FCS developed into viable Day 14 fetuses after transfer into recipients. These M16 + FCS fetuses were reduced in weight as compared with controls and M16 fetuses and had decreased expression of the imprinted H19 and insulin-like growth factor 2 genes associated with a gain of DNA methylation at an imprinting control region upstream of H19. They also displayed increased expression of the imprinted gene Grb10. The growth factor receptor binding gene Grb7, in contrast, was strongly reduced in its expression in most of the M16 + FCS fetuses. No alterations were detected for the imprinted gene MEST: Preimplantation culture in the presence of serum can influence the regulation of multiple growth-related imprinted genes, thus leading to aberrant fetal growth and development.

A New View of Radiation-Induced Cancer: Integrating Short-and Long-Term Processes. Part I: Approach

NASA Technical Reports Server (NTRS)

Shuryak, Igor; Hahnfeldt, Philip; Hlatky, Lynn; Sachs, Rainer K.; Brenner, David J.

2009-01-01

Mathematical models of radiation carcinogenesis are important for understanding mechanisms and for interpreting or extrapolating risk. There are two classes of such models: (1) long-term formalisms that track premalignant cell numbers throughout an entire lifetime but treat initial radiation dose-response simplistically and (2) short-term formalisms that provide a detailed initial dose-response even for complicated radiation protocols, but address its modulation during the subsequent cancer latency period only indirectly. We argue that integrating short- and long-term models is needed. As an example of this novel approach, we integrate a stochastic short-term initiation/ inactivation/repopulation model with a deterministic two-stage long-term model. Within this new formalism, the following assumptions are implemented: radiation initiates, promotes, or kills pre-malignant cells; a pre-malignant cell generates a clone, which, if it survives, quickly reaches a size limitation; the clone subsequently grows more slowly and can eventually generate a malignant cell; the carcinogenic potential of pre-malignant cells decreases with age.

Isolation and mutational analysis of circulating tumor cells from lung cancer patients with magnetic sifters and biochips†

PubMed Central

Earhart, Christopher M.; Hughes, Casey E.; Gaster, Richard S.; Ooi, Chin Chun; Wilson, Robert J.; Zhou, Lisa Y.; Humke, Eric W.; Xu, Lingyun; Wong, Dawson J.; Willingham, Stephen B.; Schwartz, Erich J.; Weissman, Irving L.; Jeffrey, Stefanie S.; Neal, Joel W.; Rohatgi, Rajat; Wakelee, Heather A.; Wang, Shan X.

2014-01-01

Detection and characterization of circulating tumor cells (CTCs) may reveal insights into the diagnosis and treatment of malignant disease. Technologies for isolating CTCs developed thus far suffer from one or more limitations, such as low throughput, inability to release captured cells, and reliance on expensive instrumentation for enrichment or subsequent characterization. We report a continuing development of a magnetic separation device, the magnetic sifter, which is a miniature microfluidic chip with a dense array of magnetic pores. It offers high efficiency capture of tumor cells, labeled with magnetic nanoparticles, from whole blood with high throughput and efficient release of captured cells. For subsequent characterization of CTCs, an assay, using a protein chip with giant magnetoresistive nanosensors, has been implemented for mutational analysis of CTCs enriched with the magnetic sifter. The use of these magnetic technologies, which are separate devices, may lead the way to routine preparation and characterization of “liquid biopsies” from cancer patients. PMID:23969419

Circulating erythroblasts in maternal blood are not elevated before onset of preterm labor.

PubMed

Hoesli, Irene; Danek, Milan; Lin, Dexin; Li, Ying; Hahn, Sinuhe; Holzgreve, Wolfgang

2002-11-01

Preterm labor has recently been reported to be associated with an increased release of cell free fetal deoxyribonucleic acid (DNA) into the maternal circulation. We have previously observed increases in both fetal cell traffic and cell free fetal DNA in preeclamptic pregnancies. In this study, we investigated whether fetal cell traffic is also disturbed in pregnancies with preterm labor. In a case-control study, we examined 47 pregnancies complicated by preterm contractions that occurred between 20 and 34 weeks' gestation and an equal number of matched controls. Erythroblasts were enriched for by magnetic cell sorting and enumerated. These values were then correlated with subsequent pregnancy outcome. In the study group 16 patients delivered prematurely (subgroup A). The other 31 (subgroup B) delivered at term, as did all those in the control group. No significant difference was noted in erythroblast numbers between either one of the subgroups and the controls. Contrary to the reported increased levels of free fetal DNA in maternal serum, erythroblasts in maternal blood are not elevated significantly in pregnancies with threatened premature labor or in those that deliver preterm.

Effects of hydrogen peroxide on vestibular hair cells in the guinea pig: importance of cell membrane impairment preceding cell death.

PubMed

Tanigawa, Tohru; Tanaka, Hirokazu; Hayashi, Ken; Nakayama, Meiho; Iwasaki, Satoshi; Banno, Shinya; Takumida, Masaya; Brodie, Hirally; Inafuku, Shigeru

2008-11-01

Our findings indicate that oxidative stress induces morphological changes in vestibular hair cells and subsequently leads to cell death after 2.5 h. The aim of this study was to confirm the direct effects of oxidative stress on vestibular hair cells. Vestibular hair cells isolated from guinea pigs were loaded with 1 or 10 mM H2O2, and morphological changes were observed. In addition, in a viability/cytotoxicity assay system, the numbers of dead cells in isolated cristae ampullares were counted 1, 3, and 5 h after loading with H2O2 or artificial perilymph (control). Reactive oxygen, in the form of H2O2, directly affects the cell membrane of isolated vestibular hair cells and causes swelling of the cell body, bleb formation, and shortening of the neck region. Morphological changes occur within 30 min after loading with H2O2, but a significant increase in the number of dead cells is noted only after 3 h.

Structural optimization of diphenylpyrimidine derivatives (DPPYs) as potent Bruton's tyrosine kinase (BTK) inhibitors with improved activity toward B leukemia cell lines.

PubMed

Zhao, Dan; Huang, Shanshan; Qu, Menghua; Wang, Changyuan; Liu, Zhihao; Li, Zhen; Peng, Jinyong; Liu, Kexin; Li, Yanxia; Ma, Xiaodong; Shu, Xiaohong

2017-01-27

A new series of diphenylpyrimidine derivatives (DPPYs) bearing various aniline side chains at the C-2 position of pyrimidine core were synthesized as potent BTK inhibitors. Most of these inhibitors displayed improved activity against B leukemia cell lines compared with lead compound spebrutinib. Subsequent studies showed that the peculiar inhibitor 7j, with IC 50 values of 10.5 μM against Ramos cells and 19.1 μM against Raji cells, also displayed slightly higher inhibitory ability than the novel agent ibrutinib. Moreover, compound 7j is not sensitive to normal cells PBMC, indicating low cell cytotoxicity. In addition, flow cytometry analysis indicated that 7j significantly induced the apoptosis of Ramos cells, and arrested the cell cycle at the G0/G1 phase. These explorations provided new clues to discover pyrimidine scaffold as more effective BTK inhibitors. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Metastatic potential of tumor-initiating cells in solid tumors.

PubMed

Adhikari, Amit S; Agarwal, Neeraj; Iwakuma, Tomoo

2011-01-01

The lethality of cancer is mainly caused by its properties of metastasis, drug resistance, and subsequent recurrence. Understanding the mechanisms governing these properties and developing novel strategies to overcome them will greatly improve the survival of cancer patients. Recent findings suggest that tumors are comprised of heterogeneous cell populations, and only a small fraction of these are tumorigenic with the ability to self-renew and produce phenotypically diverse tumor cell populations. Cells in this fraction are called tumor-initiating cells (TICs) or cancer stem cells (CSCs). TICs have been identified from many types of cancer. They share several similarities with normal adult stem cells including sphere-forming ability, self-renewability, and expression of stem cell surface markers and transcription factors. TICs have also been proposed to be responsible for cancer metastasis, however, scarce evidence for their metastatic potential has been provided. In this review article, we have attempted to summarize the studies which have examined the metastatic potential of TICs in solid tumors.

Radiation damage in lithium-counterdoped n/p silicon solar cells

NASA Technical Reports Server (NTRS)

Hermann, A. M.; Swartz, C. K.; Brandhorst, H. W., Jr.; Weinberg, I.

1980-01-01

Lithium counterdoped n+/p silicon solar cells were irradiated with 1 MV electrons and their post irradiation performance and low temperature annealing properties were compared to that of the 0.35 ohm cm control cells. Cells fabricated from float zone and Czochralski grown silicon were investigated. It was found that the float zone cells exhibited superior radiation resistance compared to the control cells, while no improvement was noted for the Czochralski grown cells. Room temperature and 60 C annealing studies were conducted. The annealing was found to be a combination of first and second order kinetics for short times. It was suggested that the principal annealing mechanism was migration of lithium to a radiation induced defect with subsequent neutralization of the defect by combination with lithium. The effects of base lithium gradient were investigated. It was found that cells with negative base lithium gradients exhibited poor radiation resistance and performance compared to those with positive or no lithium gradients; the latter being preferred for overall performance and radiation resistance.

Resveratrol promotes regression of renal carcinoma cells via a renin-angiotensin system suppression-dependent mechanism.

PubMed

Li, Jianchang; Qiu, Mingning; Chen, Lieqian; Liu, Lei; Tan, Guobin; Liu, Jianjun

2017-02-01

The aim of the present study was to investigate the effect of resveratrol on renal carcinoma cells and explore possible renin-angiotensin system-associated mechanisms. Subsequent to resveratrol treatment, the cell viability, apoptosis rate, cytotoxicity levels, caspase 3/7 activity and the levels of angiotensin II (AngII), AngII type 1 receptor (AT1R), vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) were evaluated in renal carcinoma cells. The effects of AngII, AT1R, VEGF and COX-2 on resveratrol-induced cell growth inhibition and apoptosis were also examined. The results indicated that resveratrol treatment may suppress growth, induce apoptosis, and decrease AngII, AT1R, VEGF and COX-2 levels in renal carcinoma ACHN and A498 cells. In addition, resveratrol-induced cell growth suppression and apoptosis were reversed when co-culturing with AT1R or VEGF. Thus, resveratrol may suppress renal carcinoma cell proliferation and induce apoptosis via an AT1R/VEGF pathway.

A Microfluidic Technique to Probe Cell Deformability

PubMed Central

Hoelzle, David J.; Varghese, Bino A.; Chan, Clara K.; Rowat, Amy C.

2014-01-01

Here we detail the design, fabrication, and use of a microfluidic device to evaluate the deformability of a large number of individual cells in an efficient manner. Typically, data for ~102 cells can be acquired within a 1 hr experiment. An automated image analysis program enables efficient post-experiment analysis of image data, enabling processing to be complete within a few hours. Our device geometry is unique in that cells must deform through a series of micron-scale constrictions, thereby enabling the initial deformation and time-dependent relaxation of individual cells to be assayed. The applicability of this method to human promyelocytic leukemia (HL-60) cells is demonstrated. Driving cells to deform through micron-scale constrictions using pressure-driven flow, we observe that human promyelocytic (HL-60) cells momentarily occlude the first constriction for a median time of 9.3 msec before passaging more quickly through the subsequent constrictions with a median transit time of 4.0 msec per constriction. By contrast, all-trans retinoic acid-treated (neutrophil-type) HL-60 cells occlude the first constriction for only 4.3 msec before passaging through the subsequent constrictions with a median transit time of 3.3 msec. This method can provide insight into the viscoelastic nature of cells, and ultimately reveal the molecular origins of this behavior. PMID:25226269

Comparative study of photothermolysis of cancer cells with nuclear-targeted or cytoplasm-targeted gold nanospheres: continuous wave or pulsed lasers

NASA Astrophysics Data System (ADS)

Huang, Xiaohua; Kang, Bin; Qian, Wei; Mackey, Megan A.; Chen, Po C.; Oyelere, Adegboyega K.; El-Sayed, Ivan H.; El-Sayed, Mostafa A.

2010-09-01

We conduct a comparative study on the efficiency and cell death pathways of continuous wave (cw) and nanosecond pulsed laser photothermal cancer therapy using gold nanospheres delivered to either the cytoplasm or nucleus of cancer cells. Cytoplasm localization is achieved using arginine-glycine-aspartate peptide modified gold nanospheres, which target integrin receptors on the cell surface and are subsequently internalized by the cells. Nuclear delivery is achieved by conjugating the gold nanospheres with nuclear localization sequence peptides originating from the simian virus. Photothermal experiments show that cell death can be induced with a single pulse of a nanosecond laser more efficiently than with a cw laser. When the cw laser is applied, gold nanospheres localized in the cytoplasm are more effective in inducing cell destruction than gold nanospheres localized at the nucleus. The opposite effect is observed when the nanosecond pulsed laser is used, suggesting that plasmonic field enhancement of the nonlinear absorption processes occurs at high localization of gold nanospheres at the nucleus. Cell death pathways are further investigated via a standard apoptosis kit to show that the cell death mechanisms depend on the type of laser used. While the cw laser induces cell death via apoptosis, the nanosecond pulsed laser leads to cell necrosis. These studies add mechanistic insight to gold nanoparticle-based photothermal therapy of cancer.

Morphological and Structural Aspects of the Extremely Halophilic Archaeon Haloquadratum walsbyi

PubMed Central

Sublimi Saponetti, Matilde; Bobba, Fabrizio; Salerno, Grazia; Scarfato, Alessandro; Corcelli, Angela; Cucolo, Annamaria

2011-01-01

Ultrathin square cell Haloquadratum walsbyi from the Archaea domain are the most abundant microorganisms in the hypersaline water of coastal salterns and continental salt lakes. In this work, we explore the cell surface of these microorganisms using amplitude-modulation atomic-force microscopy in nearly physiological conditions. We demonstrate the presence of a regular corrugation with a periodicity of 16–20 nm attributed to the surface layer (S-layer) protein lattice, striped domains asymmetrically distributed on the cell faces and peculiar bulges correlated with the presence of intracellular granules. Besides, subsequent images of cell evolution during the drying process indicate the presence of an external capsule that might correspond to the giant protein halomucin, predicted by the genome but never before observed by other microscopy studies. PMID:21559517

Morphological and structural aspects of the extremely halophilic archaeon Haloquadratum walsbyi.

PubMed

Sublimi Saponetti, Matilde; Bobba, Fabrizio; Salerno, Grazia; Scarfato, Alessandro; Corcelli, Angela; Cucolo, Annamaria

2011-04-29

Ultrathin square cell Haloquadratum walsbyi from the Archaea domain are the most abundant microorganisms in the hypersaline water of coastal salterns and continental salt lakes. In this work, we explore the cell surface of these microorganisms using amplitude-modulation atomic-force microscopy in nearly physiological conditions. We demonstrate the presence of a regular corrugation with a periodicity of 16-20 nm attributed to the surface layer (S-layer) protein lattice, striped domains asymmetrically distributed on the cell faces and peculiar bulges correlated with the presence of intracellular granules. Besides, subsequent images of cell evolution during the drying process indicate the presence of an external capsule that might correspond to the giant protein halomucin, predicted by the genome but never before observed by other microscopy studies.

Recent insights into the biology of Hodgkin lymphoma: unraveling the mysteries of the Reed-Sternberg cell.

PubMed

Roullet, Michele R; Bagg, Adam

2007-11-01

The microscopic pathology of Hodgkin lymphoma has been recognized for well over a century; however, only in the past 15 years has the enigmatic nature of this peculiar neoplasm been somewhat unraveled. This has been accomplished via a combination of the acquisition, via microdissection, of the prototypically rare malignant cells and their subsequent analysis via a variety of modalities, including genomic studies and expression profiling. This has facilitated the elucidation of the surreptitiously concealed B-cell origin of the cells, their complex but vital relationships with the surrounding micro- and macroenvironment, as well as multiple pathways involved in the pathobiology of this lymphoma. Understanding the intricacies of these intra- and extracellular pathways should allow for the development of less-toxic targeted therapies.

Transfer the multiscale texture of crystalline Si onto thin-film micromorph cell by UV nanoimprint for light trapping

NASA Astrophysics Data System (ADS)

Liu, Daiming; Wang, Qingkang; Wang, Qing

2018-05-01

Surface texturing is of great significance in light trapping for solar cells. Herein, the multiscale texture, consisting of microscale pyramids and nanoscale porous arrangement, was fabricated on crystalline Si by KOH etching and Ag-assisted HF etching processes and subsequently replicated onto glass with high fidelity by UV nanoimprint method. Light trapping of the multiscale texture was studied by spectral (reflectance, haze ratio) characterizations. Results reveal the multiscale texture provides the broadband reflection reducing, the highlighted light scattering and the additional self-cleaning behaviors. Compared with bare cell, the multiscale textured micromorph cell achieves a 4% relative increase in power conversion efficiency. This surface texturing route paves a promising way for developing low-cost, large-scale and high-efficiency solar applications.

Triptolide suppresses paraquat induced idiopathic pulmonary fibrosis by inhibiting TGFB1-dependent epithelial mesenchymal transition.

PubMed

Chen, Hong; Chen, Qun; Jiang, Chun-Ming; Shi, Guang-Yue; Sui, Bo-Wen; Zhang, Wei; Yang, Li-Zhen; Li, Zhu-Ying; Liu, Li; Su, Yu-Ming; Zhao, Wen-Cheng; Sun, Hong-Qiang; Li, Zhen-Zi; Fu, Zhou

2018-03-01

Idiopathic pulmonary fibrosis (IPF) and tumor are highly similar to abnormal cell proliferation that damages the body. This malignant cell evolution in a stressful environment closely resembles that of epithelial-mesenchymal transition (EMT). As a popular EMT-inducing factor, TGFβ plays an important role in the progression of multiple diseases. However, the drugs that target TGFB1 are limited. In this study, we found that triptolide (TPL), a Chinese medicine extract, exerts an anti-lung fibrosis effect by inhibiting the EMT of lung epithelial cells. In addition, triptolide directly binds to TGFβ and subsequently increase E-cadherin expression and decrease vimentin expression. In in vivo studies, TPL improves the survival state and inhibits lung fibrosis in mice. In summary, this study revealed the potential therapeutic effect of paraquat induced TPL in lung fibrosis by regulating TGFβ-dependent EMT progression. Copyright © 2017 Elsevier B.V. All rights reserved.

Synthesis, molecular docking and anticancer studies of peptides and iso-peptides.

PubMed

Jabeen, Farukh; Panda, Siva S; Kondratyuk, Tamara P; Park, Eun-Jung; Pezzuto, John M; Ihsan-ul-Haq; Hall, C Dennis; Katritzky, Alan R

2015-08-01

Chiral peptides and iso-peptides were synthesized in excellent yield by using benzotriazole mediated solution phase synthesis. Benzotriazole acted both as activating and leaving group, eliminating frequent use of protection and subsequent deprotection. The procedure was based on the hypothesis that epimerization should be suppressed in solution due to a faster coupling rate than SPPS. All the synthesized peptides complied with Lipinski's Ro5 except for the rotatable bonds. Inhibition of cell proliferation of cancer cell lines is one of the most commonly used methods to study the effectiveness of any anticancer agents. Synthesized peptides and iso-peptides were tested against three cancer cell lines (MCF-7, MDA-MB 231) to determine their anti-proliferative potential. NFkB was also determined. Molecular docking studies were also carried out to complement the experimental results. Copyright © 2015 Elsevier Ltd. All rights reserved.

Treatment with acetyl-l-carnitine during in vitro maturation of buffalo oocytes improves oocyte quality and subsequent embryonic development.

PubMed

Xu, Hui-Yan; Yang, Xiao-Gan; Lu, Sheng-Sheng; Liang, Xing-Wei; Lu, Yang-Qing; Zhang, Ming; Lu, Ke-Huan

2018-06-01

Oocyte quality is one of the important factors in female fertility, in vitro maturation (IVM), and subsequent embryonic development. In the present study, we assessed whether acetyl-l-carnitine (ALC) supplementation during in vitro maturation of buffalo oocytes could improve oocyte quality and subsequent embryonic development. To determine the optimal level of ALC supplementation, we matured cumulus-oocyte complexes in maturation medium supplemented with 0, 2.5, and 5 mM ALC. The oocytes with a polar body were selected for parthenogenetic activation (PA) and in vitro fertilization (IVF). We found that oocytes matured in 2.5 mM ALC had significantly higher PA blastocyst rate (P < 0.05) and blastocyst cell number than those of unsupplemented oocytes (P < 0.05) and a significantly higher IVF blastocyst rate than that of oocytes matured in 5 mM ALC (P < 0.05). In all further experiments, we supplemented the maturation medium with 2.5 mM ALC. We then tested whether ALC supplementation could improve various markers of oocytes and cumulus cells. We compared cell proliferation; concentrations of reactive oxygen species (ROS), intracellular ATP, estradiol, and progesterone; mitochondrial distribution; mitochondrial DNA copy number (mtDNA); and expression levels of four genes encoding oocyte-derived factors (GDF9, BMP15) and steroid hormones (StAR, P450scc) between the supplemented and unsupplemented oocytes and cumulus cells. Cumulus cells matured with ALC supplementation were more prolific than those matured without ALC supplementation (P < 0.05). Oocytes treated with ALC had lower concentrations of intracellular ROS (P < 0.05) and a higher rate of diffuse mitochondrial distributions (P < 0.05) than those of untreated oocytes. Additionally, the mtDNA was higher in the ALC-treated oocytes (P < 0.05) and cumulus cells (P < 0.05) than that in the untreated cells. The ALC-treated maturation medium had a higher postmaturation concentration of estradiol than that of the untreated medium (P < 0.05). Finally, the gene expression levels of P450scc and GDF9 were greater in ALC-treated oocytes and cumulus cells than those in untreated cells (P < 0.05). Therefore, in buffalo, our results suggest that ALC affects mitochondrial function, regulates oocyte-derived paracrine factors, and increases the production of steroid hormones, leading to increased quality of matured oocytes and improved embryonic development in vitro. Copyright © 2018 Elsevier Inc. All rights reserved.

Systems Modelling and the Development of Coherent Understanding of Cell Biology

ERIC Educational Resources Information Center

Verhoeff, Roald P.; Waarlo, Arend Jan; Boersma, Kerst Th.

2008-01-01

This article reports on educational design research concerning a learning and teaching strategy for cell biology in upper-secondary education introducing "systems modelling" as a key competence. The strategy consists of four modelling phases in which students subsequently develop models of free-living cells, a general two-dimensional model of…

21 CFR 864.9145 - Processing system for frozen blood.

Code of Federal Regulations, 2012 CFR

2012-04-01

... system for frozen blood is a device used to glycerolize red blood cells prior to freezing to minimize... thawing of red blood cells and to deglycerolize and wash thawed cells for subsequent reinfusion. (b... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Processing system for frozen blood. 864.9145...

21 CFR 864.9145 - Processing system for frozen blood.

Code of Federal Regulations, 2014 CFR

2014-04-01

... system for frozen blood is a device used to glycerolize red blood cells prior to freezing to minimize... thawing of red blood cells and to deglycerolize and wash thawed cells for subsequent reinfusion. (b... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Processing system for frozen blood. 864.9145...

21 CFR 864.9145 - Processing system for frozen blood.

Code of Federal Regulations, 2010 CFR

2010-04-01

... system for frozen blood is a device used to glycerolize red blood cells prior to freezing to minimize... thawing of red blood cells and to deglycerolize and wash thawed cells for subsequent reinfusion. (b... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Processing system for frozen blood. 864.9145...

21 CFR 864.9145 - Processing system for frozen blood.

Code of Federal Regulations, 2013 CFR

2013-04-01

... system for frozen blood is a device used to glycerolize red blood cells prior to freezing to minimize... thawing of red blood cells and to deglycerolize and wash thawed cells for subsequent reinfusion. (b... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Processing system for frozen blood. 864.9145...

21 CFR 864.9145 - Processing system for frozen blood.

Code of Federal Regulations, 2011 CFR

2011-04-01

... system for frozen blood is a device used to glycerolize red blood cells prior to freezing to minimize... thawing of red blood cells and to deglycerolize and wash thawed cells for subsequent reinfusion. (b... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Processing system for frozen blood. 864.9145...

A distinct first replication cycle of DNA introduced in mammalian cells

PubMed Central

Chandok, Gurangad S.; Kapoor, Kalvin K.; Brick, Rachel M.; Sidorova, Julia M.; Krasilnikova, Maria M.

2011-01-01

Many mutation events in microsatellite DNA sequences were traced to the first embryonic divisions. It was not known what makes the first replication cycles of embryonic DNA different from subsequent replication cycles. Here we demonstrate that an unusual replication mode is involved in the first cycle of replication of DNA introduced in mammalian cells. This alternative replication starts at random positions, and occurs before the chromatin is fully assembled. It is detected in various cell lines and primary cells. The presence of single-stranded regions increases the efficiency of this alternative replication mode. The alternative replication cannot progress through the A/T-rich FRA16B fragile site, while the regular replication mode is not affected by it. A/T-rich microsatellites are associated with the majority of chromosomal breakpoints in cancer. We suggest that the alternative replication mode may be initiated at the regions with immature chromatin structure in embryonic and cancer cells resulting in increased genomic instability. This work demonstrates, for the first time, differences in the replication progression during the first and subsequent replication cycles in mammalian cells. PMID:21062817

Intestinal Decontamination of Multidrug-resistant Klebsiella pneumoniae After Recurrent Infections in an Immunocompromised Host

PubMed Central

Kronman, Matthew P.; Zerr, Danielle M.; Qin, Xuan; Englund, Janet; Cornell, Cathy; Sanders, Jean E.; Myers, Jeffrey; Rayar, Jaipreet; Berry, Jessica E.; Adler, Amanda L.; Weissman, Scott J.

2014-01-01

Multidrug-resistant (MDR) Enterobacteriaceae infections are associated with increased morbidity. We describe a 20-year-old hematopoietic cell transplantation recipient with recurrent MDR Klebsiella pneumoniae infection, prolonged intestinal colonization, and subsequent intestinal decontamination. Further study should evaluate stool surveillance, molecular typing, and fecal microbiota transplantation for patients with intestinal MDR Enterobacteriaceae carriage. PMID:25041704

Comparison of Dilute Acid and Sulfite Pretreatment for enzymatic Saccharification of Earlywood and Latewood of Douglas Fir

Treesearch

Chao Zhang; Xiaochun Lei; C. Tim Scott; J.Y. Zhu; Kecheng Li

2014-01-01

This study applied dilute acid (DA) and sulfite pretreatment to overcome the recalcitrance of lignocelluloses (SPORL) to deconstruct earlywood and latewood cell walls of Douglas fir for fermentable sugars production through subsequent enzymatic hydrolysis. DA pretreatment removed almost all the hemicelluloses, while SPORL at initial pH=4.5 (SP-B) removed significant...

Dictyostelium cell death: early emergence and demise of highly polarized paddle cells.

PubMed

Levraud, Jean-Pierre; Adam, Myriam; Luciani, Marie-Françoise; de Chastellier, Chantal; Blanton, Richard L; Golstein, Pierre

2003-03-31

Cell death in the stalk of Dictyostelium discoideum, a prototypic vacuolar cell death, can be studied in vitro using cells differentiating as a monolayer. To identify early events, we examined potentially dying cells at a time when the classical signs of Dictyostelium cell death, such as heavy vacuolization and membrane lesions, were not yet apparent. We observed that most cells proceeded through a stereotyped series of differentiation stages, including the emergence of "paddle" cells showing high motility and strikingly marked subcellular compartmentalization with actin segregation. Paddle cell emergence and subsequent demise with paddle-to-round cell transition may be critical to the cell death process, as they were contemporary with irreversibility assessed through time-lapse videos and clonogenicity tests. Paddle cell demise was not related to formation of the cellulose shell because cells where the cellulose-synthase gene had been inactivated underwent death indistinguishable from that of parental cells. A major subcellular alteration at the paddle-to-round cell transition was the disappearance of F-actin. The Dictyostelium vacuolar cell death pathway thus does not require cellulose synthesis and includes early actin rearrangements (F-actin segregation, then depolymerization), contemporary with irreversibility, corresponding to the emergence and demise of highly polarized paddle cells.

Automated tumor analysis for molecular profiling in lung cancer

PubMed Central

Boyd, Clinton; James, Jacqueline A.; Loughrey, Maurice B.; Hougton, Joseph P.; Boyle, David P.; Kelly, Paul; Maxwell, Perry; McCleary, David; Diamond, James; McArt, Darragh G.; Tunstall, Jonathon; Bankhead, Peter; Salto-Tellez, Manuel

2015-01-01

The discovery and clinical application of molecular biomarkers in solid tumors, increasingly relies on nucleic acid extraction from FFPE tissue sections and subsequent molecular profiling. This in turn requires the pathological review of haematoxylin & eosin (H&E) stained slides, to ensure sample quality, tumor DNA sufficiency by visually estimating the percentage tumor nuclei and tumor annotation for manual macrodissection. In this study on NSCLC, we demonstrate considerable variation in tumor nuclei percentage between pathologists, potentially undermining the precision of NSCLC molecular evaluation and emphasising the need for quantitative tumor evaluation. We subsequently describe the development and validation of a system called TissueMark for automated tumor annotation and percentage tumor nuclei measurement in NSCLC using computerized image analysis. Evaluation of 245 NSCLC slides showed precise automated tumor annotation of cases using Tissuemark, strong concordance with manually drawn boundaries and identical EGFR mutational status, following manual macrodissection from the image analysis generated tumor boundaries. Automated analysis of cell counts for % tumor measurements by Tissuemark showed reduced variability and significant correlation (p < 0.001) with benchmark tumor cell counts. This study demonstrates a robust image analysis technology that can facilitate the automated quantitative analysis of tissue samples for molecular profiling in discovery and diagnostics. PMID:26317646

Neuron-like PC12 cell patterning on a photoactive self-assembled monolayer.

PubMed

Cheng, Nan; Cao, Xudong

2013-11-01

A new approach to pattern cells using photochemistry and self-assembled monolayer (SAM) was described in this study. Photocleavable 4,5-dimethoxy-2-nitrobenzyl chloroformate (NVOC) protected amine on an alkanethiol-gold SAM was developed for cell patterning. The cleavage of NVOC and the deprotection of amines on the SAM were controlled spatially by two sequential UV exposures with a photomask. Biomolecule patterning was achieved by introducing cell nonadhesive poly(ethylene glycol) after the first exposure and subsequently cell adhesive protein laminin after the second exposure to create surface cell adhesiveness differential for cell patterning. UV-Vis spectrophotometry was used to determine the photolysis of caged self-assembled molecules; in addition, water contact angle, atomic force microscopy, cyclic voltammetry, and X-ray photoelectron spectroscopy were used to characterize properties of different surfaces. To test the efficacy of resulting surfaces in patterning cells, a neuron-like cell line, PC12 cell line, was used. The in vitro cell studies showed successful PC12 cell patterns on the photoactive SAM surfaces. This patterning technique is unique in that it does not rely on cell adhesive or nonadhesive properties of the starting base material as both cell adhesive and cell nonadhesive molecules were individually introduced onto the base material surface through photo-uncaging at preselected regions for the ultimate cell patterning. Copyright © 2013 Wiley Periodicals, Inc.

SOX4 inhibits GBM cell growth and induces G0/G1 cell cycle arrest through Akt-p53 axis.

PubMed

Zhang, Jing; Jiang, Huawei; Shao, Jiaofang; Mao, Ruifang; Liu, Jie; Ma, Yingying; Fang, Xuefeng; Zhao, Na; Zheng, Shu; Lin, Biaoyang

2014-11-01

SOX4 is a transcription factor required for tissue development and differentiation in vertebrates. Overexpression of SOX4 has been reported in many cancers including glioblastoma multiforme (GBM), however, the underlying mechanism of actions has not been studied. In this study, we investigated the role of SOX4 in GBM. Kaplan-Meier analysis was performed to assess the association between SOX4 expression levels and survival times in primary GBM samples. Cre/lox P system was used to generate gain or loss of SOX4 in GBM cells, and microarray analysis uncovered the regulation network of SOX4 in GBM cells. High SOX4 expression was significantly associated with good prognosis of primary GBMs. SOX4 inhibited the growth of GBM cell line LN229, A172G and U87MG, partly via the activation of p53-p21 signaling and down-regulation of phosphorylated AKT1. Gene expression profiling and subsequent gene ontology analysis showed that SOX4 influenced several key pathways including the Wnt/ beta-catenin and TGF-beta signaling pathways. Our study found that SOX4 acts as a tumor suppressor in GBM cells by induce cell cycle arrest and inhibiting cell growth.

Aurora B inhibitor barasertib and cytarabine exert a greater-than-additive cytotoxicity in acute myeloid leukemia cells.

PubMed

Yamauchi, Takahiro; Uzui, Kanako; Shigemi, Hiroko; Negoro, Eiju; Yoshida, Akira; Ueda, Takanori

2013-07-01

Barasertib, an aurora B inhibitor, terminates cell division, introduces polyploidy, and consequently causes apoptosis. In the present study, we evaluated the effect of the combination of barasertib and cytarabine (ara-C), a key agent for leukemia chemotherapy, on leukemic cells in vitro. Human leukemia HL-60 cells and HL-60/ara-C20 cells, a 20-fold ara-C-resistant variant, were used. The 50% growth inhibitory concentrations of an active metabolite of barasertib, barasertib-hydroxyquinazoline-pyrazol-aniline (Barasertib-HQPA), and ara-C were 51 nM and 300 nM for HL-60 cells and 70 nM and 5300 nM for HL-60/ara-C20 cells, respectively. Barasertib-HQPA induced polyploidy with a subsequent induction of sub-G1 phase apoptosis, indicating the M-phase specific cytotoxicity. Cells treated with the S-phase specific ara-C accumulated in S phase and subsequently died through apoptosis. When HL-60 cells were treated with barasertib-HQPA and ara-C in combination, a greater-than-additive apoptosis was induced. This enhancement was obtained when the cells were treated with barasertib-HQPA prior to ara-C (37.9% sub-G1) or with both concurrently (31.2% sub-G1), but not with ara-C prior to barasertib-HQPA (17.8% sub-G1). The combination effects were similarly obtained in HL-60/ara-C20 cells with 19.7% sub-G1 for barasertib-HQPA→ara-C, 18.4% sub-G1 for both concurrently, and 13.8% sub-G1 for ara-C→barasertib-HQPA, and another leukemic U937 cells with 25.4% sub-G1 for barasertib-HQPA→ara-C, 28.2% sub-G1 for both concurrently, and 16.0% sub-G1 for ara-C→barasertib-HQPA. Barasertib-HQPA inhibited aurora B autophosphorylation and histone H3 phosphorylation in all the cell lines. Barasertib-HQPA did not inhibit DNA synthesis, allowing ara-C incorporation into DNA for its cytotoxicity. Thus, barasertib-HQPA and ara-C provided a greater-than-additive cytotoxicity in leukemic cells in vitro. © 2013 Japanese Cancer Association.

Newly synthesized bis-benzimidazole compound 8 induces apoptosis, autophagy and reactive oxygen species generation in HeLa cells.

PubMed

Chu, Naying; Yao, Guodong; Liu, Yuan; Cheng, Maosheng; Ikejima, Takashi

2016-09-01

Compound 8 (C8) is a newly synthesized bis-benzimidazole derivative and exerts significant anti-tumor activity in vitro. Previous studies demonstrated that C8 induced apoptosis and autophagy in human promyelocytic leukemia HL60 cells. However, cytotoxicity study on human peripheral blood mononuclear cells (hPBMC) showed that C8 exhibited less toxicity in normal cells. In this study, the molecular mechanism of C8 on human cervical carcinoma HeLa cells was investigated. The results showed that C8 inhibited the growth of HeLa cells and triggered both apoptotic and autophagic cell death. Subsequent experiment also indicated that reactive oxygen species (ROS) generation was induced in C8-treated HeLa cells. Since ROS scavenger decreased the ratio of apoptotic and autophagic cells, ROS generation contributed to C8-induced apoptosis and autophagy. Furthermore, inhibitors of apoptosis and autophagy also reduced ROS generation, respectively. Autophagy inhibition increased cell growth compared to C8-treated group and attenuated apoptotic cell death, indicating that C8-induced autophagy promoted apoptosis for cell death. However, the percentage of autophagic cells was enhanced when limiting apoptosis process. Taken together, C8 induced ROS-mediated apoptosis and autophagy in HeLa cells, autophagy promoted apoptosis but the former was antagonized by the latter. The data also gave us a new perspective on the anti-tumor effect of C8. Copyright © 2016 Elsevier Ltd. All rights reserved.

Targeted sonocatalytic cancer cell injury using avidin-conjugated titanium dioxide nanoparticles.

PubMed

Ninomiya, Kazuaki; Fukuda, Aya; Ogino, Chiaki; Shimizu, Nobuaki

2014-09-01

In this study, we applied sonodynamic therapy to cancer cells based on the delivery of titanium dioxide (TiO2) nanoparticles (NPs) modified with avidin protein, which preferentially discriminated cancerous cells from healthy cells. Subsequently, hydroxyl radicals were generated from the TiO2 NPs after activation by external ultrasound irradiation (TiO2/US treatment). Although 30% of the normal breast cells (human mammary epithelial cells) exhibited the uptake of avidin-modified TiO2 NPs, over 80% of the breast cancer cells (MCF-7) exhibited the uptake of avidin-TiO2 NPs. Next the effect of the TiO2/US treatment on MCF-7 cell growth was examined for up to 96 h after 1-MHz ultrasound was applied (0.1 W/cm(2), 30 s) to cells that incorporated the TiO2 NPs. No apparent cell injury was observed until 24h after the treatment, but the viable cell concentration declined to 68% compared with the control at 96 h. Copyright © 2014 Elsevier B.V. All rights reserved.

Perspectives for induced pluripotent stem cell technology: new insights into human physiology involved in somatic mosaicism.

PubMed

Nagata, Naoki; Yamanaka, Shinya

2014-01-31

Induced pluripotent stem cell technology makes in vitro reprogramming of somatic cells from individuals with various genetic backgrounds possible. By applying this technology, it is possible to produce pluripotent stem cells from biopsy samples of arbitrarily selected individuals with various genetic backgrounds and to subsequently maintain, expand, and stock these cells. From these induced pluripotent stem cells, target cells and tissues can be generated after certain differentiation processes. These target cells/tissues are expected to be useful in regenerative medicine, disease modeling, drug screening, toxicology testing, and proof-of-concept studies in drug development. Therefore, the number of publications concerning induced pluripotent stem cells has recently been increasing rapidly, demonstrating that this technology has begun to infiltrate many aspects of stem cell biology and medical applications. In this review, we discuss the perspectives of induced pluripotent stem cell technology for modeling human diseases. In particular, we focus on the cloning event occurring through the reprogramming process and its ability to let us analyze the development of complex disease-harboring somatic mosaicism.

Engineering cell-compatible paper chips for cell culturing, drug screening, and mass spectrometric sensing.

PubMed

Chen, Qiushui; He, Ziyi; Liu, Wu; Lin, Xuexia; Wu, Jing; Li, Haifang; Lin, Jin-Ming

2015-10-28

Paper-supported cell culture is an unprecedented development for advanced bioassays. This study reports a strategy for in vitro engineering of cell-compatible paper chips that allow for adherent cell culture, quantitative assessment of drug efficiency, and label-free sensing of intracellular molecules via paper spray mass spectrometry. The polycarbonate paper is employed as an excellent alternative bioscaffold for cell distribution, adhesion, and growth, as well as allowing for fluorescence imaging without light scattering. The cell-cultured paper chips are thus amenable to fabricate 3D tissue construction and cocultures by flexible deformation, stacks and assembly by layers of cells. As a result, the successful development of cell-compatible paper chips subsequently offers a uniquely flexible approach for in situ sensing of live cell components by paper spray mass spectrometry, allowing profiling the cellular lipids and quantitative measurement of drug metabolism with minimum sample pretreatment. Consequently, the developed paper chips for adherent cell culture are inexpensive for one-time use, compatible with high throughputs, and amenable to label-free and rapid analysis. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Automatic microscopy for mitotic cell location.

NASA Technical Reports Server (NTRS)

Herron, J.; Ranshaw, R.; Castle, J.; Wald, N.

1972-01-01

Advances are reported in the development of an automatic microscope with which to locate hematologic or other cells in mitosis for subsequent chromosome analysis. The system under development is designed to perform the functions of: slide scanning to locate metaphase cells; conversion of images of selected cells into binary form; and on-line computer analysis of the digitized image for significant cytogenetic data. Cell detection criteria are evaluated using a test sample of 100 mitotic cells and 100 artifacts.

In awe of subcellular complexity: 50 years of trespassing boundaries within the cell.

PubMed

Sabatini, David D

2005-01-01

In this review I describe the several stages of my research career, all of which were driven by a desire to understand the basic mechanisms responsible for the complex and beautiful organization of the eukaryotic cell. I was originally trained as an electron microscopist in Argentina, and my first major contribution was the introduction of glutaraldehyde as a fixative that preserved the fine structure of cells, which opened the way for cytochemical studies at the EM level. My subsequent work on membrane-bound ribosomes illuminated the process of cotranslational translocation of polypeptides across the ER membrane and led to the formulation, with Gunter Blobel, of the signal hypothesis. My later studies with many talented colleagues contributed to an understanding of ER structure and function and aspects of the mechanisms that generate and maintain the polarity of epithelial cells. For this work my laboratory introduced the now widely adopted Madin-Darby canine kidney (MDCK) cell line, and demonstrated the polarized budding of envelope viruses from those cells, providing a powerful new system that further advanced the field of protein traffic.

The Scaffold Immune Microenvironment: Biomaterial-Mediated Immune Polarization in Traumatic and Nontraumatic Applications.

PubMed

Sadtler, Kaitlyn; Allen, Brian W; Estrellas, Kenneth; Housseau, Franck; Pardoll, Drew M; Elisseeff, Jennifer H

2017-10-01

The immune system mediates tissue growth and homeostasis and is the first responder to injury or biomaterial implantation. Recently, it has been appreciated that immune cells play a critical role in wound healing and tissue repair and should thus be considered potentially beneficial, particularly in the context of scaffolds for regenerative medicine. In this study, we present a flow cytometric analysis of cellular recruitment to tissue-derived extracellular matrix scaffolds, where we quantitatively describe the infiltration and polarization of several immune subtypes, including macrophages, dendritic cells, neutrophils, monocytes, T cells, and B cells. We define a specific scaffold-associated macrophage (SAM) that expresses CD11b + F4/80 + CD11c +/- CD206 hi CD86 + MHCII + that are characteristic of an M2-like cell (CD206 hi ) with high antigen presentation capabilities (MHCII + ). Adaptive immune cells tightly regulate the phenotype of a mature SAM. These studies provide a foundation for detailed characterization of the scaffold immune microenvironment of a given biomaterial scaffold to determine the effect of scaffold changes on immune response and subsequent therapeutic outcome of that material.

Human Bone Marrow-Derived Mesenchymal Cell Reactions to 316L Stainless Steel: An in Vitro Study on Cell Viability and Interleukin-6 Expression.

PubMed

Anwar, Iwan Budiwan; Santoso, Asep; Saputra, Eko; Ismail, Rifky; Jamari, J; Van der Heide, Emile

2017-06-01

Purpose: Human bone marrow-derived mesenchymal cell (hBMC) reactions to 316L stainless steel (316L-SS) have never been evaluated. The objective of this study was to assess cell viability and interleukin-6 expression of hBMC cultures upon treatment with a 316L-SS implant. Methods: A cytotoxicity analysis was conducted with a 3-(4,5-dimethylthiazol 2-yl)-2,5-diphenyltetrazolium (MTT) assay after a period of 24, 48 and 72 hours of incubation. Expression of interleukin-6 was measured using enzyme-linked immunosorbent assay (ELISA). Results: Cell viability measurement was performed via IC50 formula. All treatment group showed a > 50 % cell viability with a range of 56,5 - 96,9 % at 24 hours, 51,8-77,3% at 48 hours and 70,1- 120 % at 72 hours. Interleukin-6 expression was downregulated subsequent to treatment with 316L-SS compared to the control group. Conclusion: We found that 316L-SS did not exhibit toxicity towards hBMC culture.

Human Bone Marrow-Derived Mesenchymal Cell Reactions to 316L Stainless Steel: An in Vitro Study on Cell Viability and Interleukin-6 Expression

PubMed Central

Anwar, Iwan Budiwan; Santoso, Asep; Saputra, Eko; Ismail, Rifky; Jamari, J.; Van der Heide, Emile

2017-01-01

Purpose: Human bone marrow-derived mesenchymal cell (hBMC) reactions to 316L stainless steel (316L-SS) have never been evaluated. The objective of this study was to assess cell viability and interleukin-6 expression of hBMC cultures upon treatment with a 316L-SS implant. Methods: A cytotoxicity analysis was conducted with a 3-(4,5-dimethylthiazol 2-yl)-2,5-diphenyltetrazolium (MTT) assay after a period of 24, 48 and 72 hours of incubation. Expression of interleukin-6 was measured using enzyme-linked immunosorbent assay (ELISA). Results: Cell viability measurement was performed via IC50 formula. All treatment group showed a > 50 % cell viability with a range of 56,5 - 96,9 % at 24 hours, 51,8-77,3% at 48 hours and 70,1- 120 % at 72 hours. Interleukin-6 expression was downregulated subsequent to treatment with 316L-SS compared to the control group. Conclusion: We found that 316L-SS did not exhibit toxicity towards hBMC culture. PMID:28761837

E-cadherin expression increases cell proliferation by regulating energy metabolism through nuclear factor-κB in AGS cells.

PubMed

Park, Song Yi; Shin, Jee-Hye; Kee, Sun-Ho

2017-09-01

β-Catenin is a central player in Wnt signaling, and activation of Wnt signaling is associated with cancer development. E-cadherin in complex with β-catenin mediates cell-cell adhesion, which suppresses β-catenin-dependent Wnt signaling. Recently, a tumor-suppressive role for E-cadherin has been reconsidered, as re-expression of E-cadherin was reported to enhance the metastatic potential of malignant tumors. To explore the role of E-cadherin, we established an E-cadherin-expressing cell line, EC96, from AGS cells that featured undetectable E-cadherin expression and a high level of Wnt signaling. In EC96 cells, E-cadherin re-expression enhanced cell proliferation, although Wnt signaling activity was reduced. Subsequent analysis revealed that nuclear factor-κB (NF-κB) activation and consequent c-myc expression might be involved in E-cadherin expression-mediated cell proliferation. To facilitate rapid proliferation, EC96 cells enhance glucose uptake and produce ATP using both mitochondria oxidative phosphorylation and glycolysis, whereas AGS cells use these mechanisms less efficiently. These events appeared to be mediated by NF-κB activation. Therefore, E-cadherin re-expression and subsequent induction of NF-κB signaling likely enhance energy production and cell proliferation. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Anti-cancer activity of withaferin A in B-cell lymphoma

PubMed Central

McKenna, MK; Gachuki, BW; Alhakeem, SS; Oben, KN; Rangnekar, VM; Gupta, RC; Bondada, S

2015-01-01

Withaferin A (WA), a withanolide from the plant, Ashwagandha (Withania somnifera) used in Ayurvedic medicine, has been found to be valuable in the treatment of several medical ailments. WA has been found to have anticancer activity against various solid tumors, but its effects on hematological malignancies have not been studied in detail. WA strongly inhibited the survival of several human and murine B cell lymphoma cell lines. Additionally, in vivo studies with syngeneic-graft lymphoma cells suggest that WA inhibits the growth of tumor but does not affect other proliferative tissues. We demonstrate that WA inhibits the efficiency of NF-κB nuclear translocation in diffuse large B cell lymphomas and found that WA treatment resulted in a significant decrease in protein levels involved in B cell receptor signaling and cell cycle regulation. WA inhibited the activity of heat shock protein (Hsp) 90 as reflected by a sharp increase in Hsp70 expression levels. Hence, we propose that the anti-cancer effects of WA in lymphomas are likely due to its ability to inhibit Hsp90 function and subsequent reduction of critical kinases and cell cycle regulators that are clients of Hsp90. PMID:26020511

Anti-cancer activity of withaferin A in B-cell lymphoma.

PubMed

McKenna, M K; Gachuki, B W; Alhakeem, S S; Oben, K N; Rangnekar, V M; Gupta, R C; Bondada, S

2015-01-01

Withaferin A (WA), a withanolide from the plant, Ashwagandha (Withania somnifera) used in Ayurvedic medicine, has been found to be valuable in the treatment of several medical ailments. WA has been found to have anticancer activity against various solid tumors, but its effects on hematological malignancies have not been studied in detail. WA strongly inhibited the survival of several human and murine B cell lymphoma cell lines. Additionally, in vivo studies with syngeneic-graft lymphoma cells suggest that WA inhibits the growth of tumor but does not affect other proliferative tissues. We demonstrate that WA inhibits the efficiency of NF-κB nuclear translocation in diffuse large B cell lymphomas and found that WA treatment resulted in a significant decrease in protein levels involved in B cell receptor signaling and cell cycle regulation. WA inhibited the activity of heat shock protein (Hsp) 90 as reflected by a sharp increase in Hsp70 expression levels. Hence, we propose that the anti-cancer effects of WA in lymphomas are likely due to its ability to inhibit Hsp90 function and subsequent reduction of critical kinases and cell cycle regulators that are clients of Hsp90.

Nucleosome architecture throughout the cell cycle

PubMed Central

Deniz, Özgen; Flores, Oscar; Aldea, Martí; Soler-López, Montserrat; Orozco, Modesto

2016-01-01

Nucleosomes provide additional regulatory mechanisms to transcription and DNA replication by mediating the access of proteins to DNA. During the cell cycle chromatin undergoes several conformational changes, however the functional significance of these changes to cellular processes are largely unexplored. Here, we present the first comprehensive genome-wide study of nucleosome plasticity at single base-pair resolution along the cell cycle in Saccharomyces cerevisiae. We determined nucleosome organization with a specific focus on two regulatory regions: transcription start sites (TSSs) and replication origins (ORIs). During the cell cycle, nucleosomes around TSSs display rearrangements in a cyclic manner. In contrast to gap (G1 and G2) phases, nucleosomes have a fuzzier organization during S and M phases, Moreover, the choreography of nucleosome rearrangements correlate with changes in gene expression during the cell cycle, indicating a strong association between nucleosomes and cell cycle-dependent gene functionality. On the other hand, nucleosomes are more dynamic around ORIs along the cell cycle, albeit with tighter regulation in early firing origins, implying the functional role of nucleosomes on replication origins. Our study provides a dynamic picture of nucleosome organization throughout the cell cycle and highlights the subsequent impact on transcription and replication activity. PMID:26818620

Synergistic antibacterial and antibiofilm efficacy of nisin in combination with p-coumaric acid against food-borne bacteria Bacillus cereus and Salmonella typhimurium.

PubMed

Bag, A; Chattopadhyay, R R

2017-11-01

The aim of the study was to evaluate possible antibacterial and antibiofilm efficacy of a bacteriocin, nisin with two essential oil components linalool and p-coumaric acid in combination against food-borne bacteria Bacillus cereus and Salmonella typhimurium. Their inhibition effects on planktonic cells and preformed biofilms were evaluated using microbroth dilution and checkerboard titration methods. Nisin/p-coumaric acid combination showed synergistic effects against planktonic cells of both the studied bacteria, whereas nisin/linalool combination showed synergistic activity against B. cereus and additive effect against S. typhimurium. In preformed biofilms, nisin by itself failed to show >50% antibiofilm efficacy against both the studied bacteria, but in combination with linalool and p-coumaric acid, it exerted >50% antibiofilm efficacy. On the basis of fractional inhibitory concentration indices values, nisin/p-coumaric acid combination exhibited synergistic antibiofilm activity, whereas nisin/linalool combination showed additive effects against preformed biofilms of studied bacteria. The results provide evidence that p-coumaric acid due to its synergistic interactions with nisin against planktonic cells and biofilms of both Gram-positive and Gram-negative food-borne bacteria enhanced the antibacterial spectrum of nisin, which subsequently may facilitate their use in the food industry. In the present work, synergistic interactions between a bacteriocin, nisin and essential oil component p-coumaric acid on planktonic cells as well as on biofilms of Gram-positive and Gram-negative food-borne bacteria have been reported. The results of this study provide evidence that nisin/p-coumaric acid combination can be considered as a promising source for development of more potent broad spectrum antimicrobial blend for food preservation, which subsequently may facilitate their use in the food industry. To the best of our knowledge, this is the first report of the antibacterial and antibiofilm efficacy of nisin in combination with essential oil components against food-borne bacteria. © 2017 The Society for Applied Microbiology.

Dictyostelium cell death

PubMed Central

Levraud, Jean-Pierre; Adam, Myriam; Luciani, Marie-Françoise; de Chastellier, Chantal; Blanton, Richard L.; Golstein, Pierre

2003-01-01

Cell death in the stalk of Dictyostelium discoideum, a prototypic vacuolar cell death, can be studied in vitro using cells differentiating as a monolayer. To identify early events, we examined potentially dying cells at a time when the classical signs of Dictyostelium cell death, such as heavy vacuolization and membrane lesions, were not yet apparent. We observed that most cells proceeded through a stereotyped series of differentiation stages, including the emergence of “paddle” cells showing high motility and strikingly marked subcellular compartmentalization with actin segregation. Paddle cell emergence and subsequent demise with paddle-to-round cell transition may be critical to the cell death process, as they were contemporary with irreversibility assessed through time-lapse videos and clonogenicity tests. Paddle cell demise was not related to formation of the cellulose shell because cells where the cellulose-synthase gene had been inactivated underwent death indistinguishable from that of parental cells. A major subcellular alteration at the paddle-to-round cell transition was the disappearance of F-actin. The Dictyostelium vacuolar cell death pathway thus does not require cellulose synthesis and includes early actin rearrangements (F-actin segregation, then depolymerization), contemporary with irreversibility, corresponding to the emergence and demise of highly polarized paddle cells. PMID:12654899

Colloidal crystal based plasma polymer patterning to control Pseudomonas aeruginosa attachment to surfaces.

PubMed

Pingle, Hitesh; Wang, Peng-Yuan; Thissen, Helmut; McArthur, Sally; Kingshott, Peter

2015-12-02

Biofilm formation on medical implants and subsequent infections are a global problem. A great deal of effort has focused on developing chemical contrasts based on micro- and nanopatterning for studying and controlling cells and bacteria at surfaces. It has been known that micro- and nanopatterns on surfaces can influence biomolecule adsorption, and subsequent cell and bacterial adhesion. However, less focus has been on precisely controlling patterns to study the initial bacterial attachment mechanisms and subsequently how the patterning influences the role played by biomolecular adsorption on biofilm formation. In this work, the authors have used colloidal self-assembly in a confined area to pattern surfaces with colloidal crystals and used them as masks during allylamine plasma polymer (AAMpp) deposition to generate highly ordered patterns from the micro- to the nanoscale. Polyethylene glycol (PEG)-aldehyde was grafted to the plasma regions via "cloud point" grafting to prevent the attachment of bacteria on the plasma patterned surface regions, thereby controlling the adhesive sites by choice of the colloidal crystal morphology. Pseudomonas aeruginosa was chosen to study the bacterial interactions with these chemically patterned surfaces. Scanning electron microscope, x-ray photoelectron spectroscopy (XPS), atomic force microscopy, and epifluorescence microscopy were used for pattern characterization, surface chemical analysis, and imaging of attached bacteria. The AAMpp influenced bacterial attachment because of the amine groups displaying a positive charge. XPS results confirm the successful grafting of PEG on the AAMpp surfaces. The results showed that PEG patterns can be used as a surface for bacterial patterning including investigating the role of biomolecular patterning on bacterial attachment. These types of patterns are easy to fabricate and could be useful in further applications in biomedical research.

Basal cell skin cancer and the risk of second primary cancers: a cancer registry-based study in Lithuania.

PubMed

Krilaviciute, Agne; Vincerzevskiene, Ieva; Smailyte, Giedre

2016-07-01

The aim of this population-based cohort study was to determine the risk of second primary cancer in basal cell carcinoma (BCC) patients in Lithuania. This analysis was based on patients diagnosed with BCC in Lithuania between 1998 and 2007 and followed until 2011. Standardized incidence ratios for subsequent cancers as a ratio of observed number of cancer cases in people with previous BCC diagnosis to the expected number of cancer cases in the underlying general population were calculated. After diagnosis of BCC, 1442 new cases of selected cancers were diagnosed. Compared with the general population, the incidence of all new primaries combined after BCC was very close to expected. Statistically meaningful increase in developing subsequent cancer was obtained for Hodgkin's lymphoma, prostate cancer, and leukemia in men, and for cancers of the lip, lung, and breast in women. Risk of melanoma and thyroid cancer was significantly elevated in both sexes. Relative risk of cancer of the eye was increased although not significant. In our study, we found increased cancer risk for cancers related to sun exposure. In addition, increased risks were identified for Hodgkin's lymphoma, thyroid cancer, leukemia, prostate, and breast cancer in BCC patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Targeting dendritic cells through gold nanoparticles: A review on the cellular uptake and subsequent immunological properties.

PubMed

Ahmad, Suhana; Zamry, Anes Ateqah; Tan, Hern-Tze Tina; Wong, Kah Keng; Lim, JitKang; Mohamud, Rohimah

2017-11-01

Gold nanoparticles (NPs) have been proposed as a highly potential tool in immunotherapies due to its advantageous properties including customizable size and shapes, surface functionality and biocompatibility. Dendritic cells (DCs), the sentinels of immune response, have been of interest to be manipulated by using gold NPs for targeted delivery of immunotherapeutic agent. Researches done especially in human DCs showed a variation of gold NPs effects on cellular uptake and internalization, DC maturation and subsequent T cells priming as well as cytotoxicity. In this review, we describe the synthesis and physiochemical properties of gold NPs as well as the importance of gold NPs in immunotherapies through their actions on human DCs. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Studies of teratomas in mice: possibilities for the future production of animal models.

PubMed Central

Lehman, J. M.

1980-01-01

The murine teratoma-teratocarcinoma has become an interesting model for the study of neoplastic transformation, developmental biology, and possibly a useful system for genetic studies. These tumors arise spontaneously in 129 strain mice and can be induced in other strains by transplanting early embryos or portions of embryos into extrauterine sites. The majority of these tumors are benign, but some are capable of transplantation due to the presence of the stem cell, embryonal carcinoma, which is a multipotential cell able to proliferate and also differentiate into tissues and cell types representative of all the embryonic germ layers. It has been elegantly shown by transplantation of embryonal carcinoma cells into blastocysts which are then placed into a pseudopregnant mouse that a normal mouse is obtained composed of cells from the host blastocyst and also cells from the malignant embryonal carcinoma. Therefore, under this set of circumstances, embryonal carcinoma cells are induced to functionally differentiate into multiple cell and tissue types which are benign and able to contribute to the development of a mouse. The adaptation of the embryonal carcinoma cell to tissue culture has allowed the manipulation of these cells with subsequent selection of mutant cells which can be further transplanted into blastocysts to obtain a mouse which contains these mutant cells. If the mutant cells have populated the germ line, it may be possible to obtain a stock of mice with the lesion present in all cells. This system may be exploitable for studies in neoplasia, developmental biology, and with proper selection procedures, allow the development of new genetic strains of mice. PMID:7457573

The effects of dynamic loading on the intervertebral disc.

PubMed

Chan, Samantha C W; Ferguson, Stephen J; Gantenbein-Ritter, Benjamin

2011-11-01

Loading is important to maintain the balance of matrix turnover in the intervertebral disc (IVD). Daily cyclic diurnal assists in the transport of large soluble factors across the IVD and its surrounding circulation and applies direct and indirect stimulus to disc cells. Acute mechanical injury and accumulated overloading, however, could induce disc degeneration. Recently, there is more information available on how cyclic loading, especially axial compression and hydrostatic pressure, affects IVD cell biology. This review summarises recent studies on the response of the IVD and stem cells to applied cyclic compression and hydrostatic pressure. These studies investigate the possible role of loading in the initiation and progression of disc degeneration as well as quantifying a physiological loading condition for the study of disc degeneration biological therapy. Subsequently, a possible physiological/beneficial loading range is proposed. This physiological/beneficial loading could provide insight into how to design loading regimes in specific system for the testing of various biological therapies such as cell therapy, chemical therapy or tissue engineering constructs to achieve a better final outcome. In addition, the parameter space of 'physiological' loading may also be an important factor for the differentiation of stem cells towards most ideally 'discogenic' cells for tissue engineering purpose.

Vascular endothelial growth factor-A enhances indoleamine 2,3-dioxygenase expression by dendritic cells and subsequently impacts lymphocyte proliferation

PubMed Central

Marti, Luciana Cavalheiro; Pavon, Lorena; Severino, Patricia; Sibov, Tatiana; Guilhen, Daiane; Moreira-Filho, Carlos Alberto

2013-01-01

Dendritic cells (DCs) are antigen (Ag)-presenting cells that activate and stimulate effective immune responses by T cells, but can also act as negative regulators of these responses and thus play important roles in immune regulation. Pro-angiogenic vascular endothelial growth factor (VEGF) has been shown to cause defective DC differentiation and maturation. Previous studies have demonstrated that the addition of VEGF to DC cultures renders these cells weak stimulators of Ag-specific T cells due to the inhibitory effects mediated by VEGF receptor 1 (VEGFR1) and/or VEGFR2 signalling. As the enzyme indoleamine 2,3-dioxygenase (IDO) is recognised as an important negative regulator of immune responses, this study aimed to investigate whether VEGF affects the expression of IDO by DCs and whether VEGF-matured DCs acquire a suppressor phenotype. Our results are the first to demonstrate that VEGF increases the expression and activity of IDO in DCs, which has a suppressive effect on Ag-specific and mitogen-stimulated lymphocyte proliferation. These mechanisms have broad implications for the study of immunological responses and tolerance under conditions as diverse as cancer, graft rejection and autoimmunity. PMID:24141959

Targeting innate immunity to downmodulate adaptive immunity and reverse type 1 diabetes

PubMed Central

Itoh, Arata; Ridgway, William M

2017-01-01

Type 1 diabetes (T1D) is characterized by specific destruction of pancreatic insulin-producing beta cells accompanied by evidence of beta-cell-directed autoimmunity such as autoreactive T cells and islet autoantibodies (IAAs). Currently, T1D cannot be prevented or reversed in humans. T1D is easy to prevent in the nonobese diabetic (NOD) spontaneous mouse model but reversing new-onset T1D in mice is more difficult. Since the discovery of the T-cell receptor in the 1980s and the subsequent identification of autoreactive T cells directed toward beta-cell antigens (eg, insulin, glutamic acid decarboxylase), the dream of antigen-specific immunotherapy has dominated the field with its promise of specificity and limited side effects. While such approaches have worked in the NOD mouse, however, dozens of human trials have failed. Broader immunosuppressive approaches (originally cyclosporine, subsequently anti-CD3 antibody) have shown partial successes (e.g., prolonged C peptide preservation) but no major therapeutic efficacy or disease reversal. Human prevention trials have failed, despite the ease of such approaches in the NOD mouse. In the past 50 years, the incidence of T1D has increased dramatically, and one explanation is the “hygiene hypothesis”, which suggests that decreased exposure of the innate immune system to environmental immune stimulants (e.g., bacterial products such as Toll-like receptor (TLR) 4-stimulating lipopolysaccharide [LPS]) dramatically affects the adaptive immune system and increases subsequent autoimmunity. We have tested the role of innate immunity in autoimmune T1D by treating acute-onset T1D in NOD mice with anti-TLR4/MD-2 agonistic antibodies and have shown a high rate of disease reversal. The TLR4 antibodies do not directly stimulate T cells but induce tolerogenic antigen-presenting cells (APCs) that mediate decreased adaptive T-cell responses. Here, we review our current knowledge and suggest future prospects for targeting innate immunity in T1D immunotherapy. PMID:28580341