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Sample records for mucin-domain-containing molecule-3 tim-3

  1. Effects of T cell immunoglobulin and mucin domain-containing molecule-3 signaling molecule on human monocyte-derived dendritic cells with hepatitis B virus surface antigen stimulation in vitro.

    PubMed

    Yu, Zhenjun; Jiang, Ting; Zhu, Min; Pan, Kechuan; Yan, Fei; Zhu, Jiansheng

    2016-03-01

    The aim of the present study was to investigate the in vitro effects of hepatitis B virus surface antigen (HBsAg) on the immune function of human monocyte-derived dendritic cells (MD‑DCs), and the moderating role of T cell immunoglobulin and mucin domain‑containing molecule‑3 (Tim‑3) signaling molecule. The monocytes, obtained from healthy adult peripheral blood, were incubated with recombinant human granulocyte‑macrophage colony‑stimulating factor and interleukin (IL)‑4 to induce DCs. DC‑associated cell markers were detected using flow cytometry. MD‑DCs were treated with HBsAg (5 µg/ml) in vitro for 48 h and subsequently, cell markers, lymphocyte stimulatory capacity, signaling protein and downstream cytokines were assessed. In addition, a Tim‑3 monoclonal antibody was used to inhibit the Tim‑3 signaling pathway, and subsequently the immune responses of MD‑DCs to HBsAg stimulation were determined using the aforementioned method. The cell phenotype expressions of MD‑DCs were all significantly increased with cluster of differentiation (CD)11c at 70.09±0.57%, human leukocyte antigen‑DR at 79.83±2.12%, CD80 at 48.33±7.34% and CD86 at 44.21±5.35%. The treatment of MD‑DCs with HBsAg resulted in a CD80 and CD86 enhanced expression, enhanced lymphocyte stimulatory capacity, upregulated expression of Tim‑3 and nuclear factor‑κB (NF‑κB), as well as enhanced cytokine secretion of IL‑6, IL‑10 and interferon (IFN)‑γ. However, a reduced immune response of MD‑DCs in response to HBsAg stimulation was observed when the Tim‑3 signaling pathway was inhibited prior to stimulation. The expression of NF‑κB was decreased and the cytokine secretion level of IL‑6, IL‑10 and IFN‑γ were downregulated. The treatment with HBsAg in vitro resulted in an enhanced immune response of MD‑DCs, which may be positively regulated by the Tim-3 signaling molecule. PMID:26820685

  2. Expansion of dysfunctional Tim-3-expressing effector memory CD8+ T cells during simian immunodeficiency virus infection in rhesus macaques.

    PubMed

    Fujita, Tsuyoshi; Burwitz, Benjamin J; Chew, Glen M; Reed, Jason S; Pathak, Reesab; Seger, Elizabeth; Clayton, Kiera L; Rini, James M; Ostrowski, Mario A; Ishii, Naoto; Kuroda, Marcelo J; Hansen, Scott G; Sacha, Jonah B; Ndhlovu, Lishomwa C

    2014-12-01

    The T cell Ig- and mucin domain-containing molecule-3 (Tim-3) negative immune checkpoint receptor demarcates functionally exhausted CD8(+) T cells arising from chronic stimulation in viral infections like HIV. Tim-3 blockade leads to improved antiviral CD8(+) T cell responses in vitro and, therefore, represents a novel intervention strategy to restore T cell function in vivo and protect from disease progression. However, the Tim-3 pathway in the physiologically relevant rhesus macaque SIV model of AIDS remains uncharacterized. We report that Tim-3(+)CD8(+) T cell frequencies are significantly increased in lymph nodes, but not in peripheral blood, in SIV-infected animals. Tim-3(+)PD-1(+)CD8(+) T cells are similarly increased during SIV infection and positively correlate with SIV plasma viremia. Tim-3 expression was found primarily on effector memory CD8(+) T cells in all tissues examined. Tim-3(+)CD8(+) T cells have lower Ki-67 content and minimal cytokine responses to SIV compared with Tim-3(-)CD8(+) T cells. During acute-phase SIV replication, Tim-3 expression peaked on SIV-specific CD8(+) T cells by 2 wk postinfection and then rapidly diminished, irrespective of mutational escape of cognate Ag, suggesting non-TCR-driven mechanisms for Tim-3 expression. Thus, rhesus Tim-3 in SIV infection partially mimics human Tim-3 in HIV infection and may serve as a novel model for targeted studies focused on rejuvenating HIV-specific CD8(+) T cell responses. PMID:25348621

  3. Tim-3 polymorphism downregulates gene expression and is involved in the susceptibility to ankylosing spondylitis.

    PubMed

    Wang, Mingfei; Ji, Bin; Wang, Jian; Cheng, Xiangyu; Zhou, Qiang; Zhou, Junjie; Cao, Chengfu; Guo, Qunfeng

    2014-10-01

    Ankylosing spondylitis (AS) is a chronic inflammatory disorder primarily affecting the sacroiliac joints and the spine. T-cell immunoglobulin- and mucin-domain-containing molecule 3 (TIM-3) has been established as a negative regulatory molecule that plays a critical role in controlling inflammation. Studies have shown that polymorphisms in TIM-3 gene may be associated with inflammatory diseases. The current study investigated the association between polymorphisms in the TIM-3 gene and susceptibility to AS, and it examined the effects of these polymorphisms on gene expression. Two polymorphisms in TIM-3 -574G/T and +4259T/G polymorphisms were identified by polymerase chain reaction-restriction fragment length polymorphism in 282 AS patients and 298 healthy controls. Results showed that frequency of the TIM-3 -574GT genotype was significantly increased in cases than in controls (Odd ratio [OR]=2.50, 95% confidence interval [CI]: 1.39-4.48, p=0.002). Similarly, TIM-3 -574T allele revealed a positive association with the disease (OR=2.39, p=0.002). The TIM-3 +4259T/G polymorphism did not show any correlation with AS. We further evaluated TIM-3 mRNA and protein levels in CD4(+) T cells, CD8(+) T cells, and monocytes from subjects carrying different TIM-3 genotypes. Results revealed that subjects carrying polymorphic -574GT genotype had significantly lower TIM-3 mRNA and protein levels in CD4(+) T cells, CD8(+) T cells, and monocytes than those with wild-type GG genotype. These data suggest that TIM-3 polymorphism is associated with increased susceptibility to AS possibly by downregulating gene expression. PMID:24905803

  4. Blockade of Tim-3 Pathway Ameliorates Interferon-γ Production from Hepatic CD8+ T Cells in a Mouse Model of Hepatitis B Virus Infection

    PubMed Central

    Ju, Ying; Hou, Nan; Zhang, Xiaoning; Zhao, Di; Liu, Ying; Wang, Jinjin; Luan, Fang; Shi, Wei; Zhu, Faliang; Sun, Wensheng; Zhang, Lining; Gao, Chengjiang; Gao, Lifen; Liang, Xiaohong; Ma, Chunhong

    2009-01-01

    T cell immunoglobulin- and mucin-domain-containing molecule-3 (Tim-3) has been reported to participate in the pathogenesis of inflammatory diseases. However, whether Tim-3 is involved in hepatitis B virus (HBV) infection remains unknown. Here, we studied the expression and function of Tim-3 in a hydrodynamics-based mouse model of HBV infection. A significant increase of Tim-3 expression on hepatic T lymphocytes, especially on CD8+ T cells, was demonstrated in HBV model mice from day 7 to day 18. After Tim-3 knockdown by specific shRNAs, significantly increased IFN-γ production from hepatic CD8+ T cells in HBV model mice was observed. Very interestingly, we found Tim-3 expression on CD8+ T cells was higher in HBV model mice with higher serum anti-HBs production. Moreover, Tim-3 knockdown influenced anti-HBs production in vivo. Collectively, our data suggested that Tim-3 might act as a potent regulator of antiviral T-cell responses in HBV infection. PMID:19254478

  5. TIM-3 expression in lymphoma cells predicts chemoresistance in patients with adult T-cell leukemia/lymphoma

    PubMed Central

    Horlad, Hasita; Ohnishi, Koji; Ma, Chaoya; Fujiwara, Yukio; Niino, Daisuke; Ohshima, Koichi; Jinushi, Masahisa; Matsuoka, Masao; Takeya, Motohiro; Komohara, Yoshihiro

    2016-01-01

    Adult T-cell leukemia/lymphoma (ATLL), an aggressive type of malignant lymphoma, is highly resistant to chemotherapy. However, the detailed mechanisms of the chemoresistance of ATLL have never been elucidated. We previously demonstrated that direct cell-cell interaction between macrophages and lymphoma cells was significantly associated with lymphoma progression in patients with ATLL. The present study aimed to further analyze the effects of cell-cell interaction between macrophages and ATLL cells by means of cell culture studies and immunohistochemical analysis using human ATLL samples. It was found that direct co-culture with macrophages induced chemoresistance in the ATLL ATN-1 cell line, but not in other cell lines, including TL-Mor, ED and ATL-2S. It was also found that expression of the T cell Ig and mucin domain-containing molecule-3 (TIM-3) was induced in ATN-1 cells by their long-term co-culture with macrophages. TIM-3 gene transfection induced chemoresistance in the ATN-1 cells. Immunostaining of ATLL tissues showed TIM-3 expression in 25 out of 58 ATLL cases. Although TIM-3 expression was not associated with overall survival or T classification, it was associated with resistance to chemotherapy. TIM-3 expression is therefore considered to be a marker for predicting the efficacy of chemotherapy, and TIM-3-associated signals may be a therapeutic target for patients with ATLL. PMID:27446463

  6. Upregulation of Tim-3 on CD4+ T cells is associated with Th1/Th2 imbalance in patients with allergic asthma

    PubMed Central

    Tang, Fei; Wang, Fukun; An, Liyun; Wang, Xianling

    2015-01-01

    T cell Ig and mucin domain-containing molecule-3 (Tim-3) is a negative regulator preferentially expressed on Th1 cells. Allergic asthma is a clinical syndrome well characterized by Th1/Th2 imbalance. To investigate the role of Tim-3 in the pathogenesis of asthma and its relationship with Th1/Th2 imbalance, a total of 40 patients with allergic asthma and 40 healthy controls were enrolled. Expression of Tim-3 and Th1/Th2 imbalance as well as the relationship between them was analyzed by flow cytometry and real-time PCR. Peripheral blood mononuclear cells (PBMCs) were cultured in vitro and anti-Tim-3 was used to block Tim-3 signaling; Th1/Th2 cytokines in the culture supernatant were detected by enzyme linked immunosorbent assay (ELISA). CD4+ T cells and B cells were sorted and co-cultured in vitro, and anti-Tim-3 was used to block Tim-3 signaling; Total IgG/IgE in the culture supernatant was detected by ELISA. The mRNA level of T-bet and IFN-γ were significantly decreased in allergic asthma patients, while GATA-3 and IL-4 were significantly increased. Expression of Tim-3 on CD4+ T cells was much higher in allergic asthma patients and it was negatively correlated with T-bet/GATA-3 ratio or IFN-γ/IL-4 ratio. Blocking of Tim-3 significantly increased Th1 cytokines (TNF-α and IFN-γ) and decreased Th2 cytokines (IL-4, IL-5, IL-13) in the culture supernatant of PBMCs. Blocking of Tim-3 dramatically reduced the production of IgG and IgE in the co-culture supernatant of CD4+ T cells and B cells. In conclusion, Tim-3 was up-regulated in allergic asthma patients and related with the Th1/Th2 imbalance. Blocking of Tim-3 may be of therapeutic benefit by enhancing the Th1 cytokines response, down-regulating the Th2 cytokines response, and reducing IgG/IgE production. PMID:26064278

  7. TIM-3 Suppresses Anti-CD3/CD28-Induced TCR Activation and IL-2 Expression through the NFAT Signaling Pathway

    PubMed Central

    Tomkowicz, Brian; Walsh, Eileen; Cotty, Adam; Verona, Raluca; Sabins, Nina; Kaplan, Fred; Santulli-Marotto, Sandy; Chin, Chen-Ni; Mooney, Jill; Lingham, Russell B.; Naso, Michael; McCabe, Timothy

    2015-01-01

    TIM-3 (T cell immunoglobulin and mucin-domain containing protein 3) is a member of the TIM family of proteins that is preferentially expressed on Th1 polarized CD4+ and CD8+ T cells. Recent studies indicate that TIM-3 serves as a negative regulator of T cell function (i.e. T cell dependent immune responses, proliferation, tolerance, and exhaustion). Despite having no recognizable inhibitory signaling motifs, the intracellular tail of TIM-3 is apparently indispensable for function. Specifically, the conserved residues Y265/Y272 and surrounding amino acids appear to be critical for function. Mechanistically, several studies suggest that TIM-3 can associate with interleukin inducible T cell kinase (ITK), the Src kinases Fyn and Lck, and the p85 phosphatidylinositol 3-kinase (PI3K) adaptor protein to positively or negatively regulate IL-2 production via NF-κB/NFAT signaling pathways. To begin to address this discrepancy, we examined the effect of TIM-3 in two model systems. First, we generated several Jurkat T cell lines stably expressing human TIM-3 or murine CD28-ECD/human TIM-3 intracellular tail chimeras and examined the effects that TIM-3 exerts on T cell Receptor (TCR)-mediated activation, cytokine secretion, promoter activity, and protein kinase association. In this model, our results demonstrate that TIM-3 inhibits several TCR-mediated phenotypes: i) NF-kB/NFAT activation, ii) CD69 expression, and iii) suppression of IL-2 secretion. To confirm our Jurkat cell observations we developed a primary human CD8+ cell system that expresses endogenous levels of TIM-3. Upon TCR ligation, we observed the loss of NFAT reporter activity and IL-2 secretion, and identified the association of Src kinase Lck, and PLC-γ with TIM-3. Taken together, our results support the conclusion that TIM-3 is a negative regulator of TCR-function by attenuating activation signals mediated by CD3/CD28 co-stimulation. PMID:26492563

  8. Increased expression of human T-cell immunoglobulin- and mucin-domain-containing molecule-4 in peripheral blood mononuclear cells from patients with system lupus erythematosus

    PubMed Central

    Zhao, Peiqing; Xu, Liyun; Wang, Piming; Liang, Xiaohong; Qi, Jianni; Liu, Peng; Guo, Chun; Zhang, Lining; Ma, Chunhong; Gao, Lifen

    2010-01-01

    Systemic lupus erythematosus (SLE) is a prototypic autoimmune disease. Innate and adaptive immunity cooperatively contribute to the development of SLE. Antigen-presenting cells (APCs) have been suggested to link innate and adaptive immunity. T-cell immunoglobulin- and mucin-domain-containing molecule-4 (Tim-4; also known as Timd4), expressed primarily on the surface of APCs, is a member of the TIM family, a recently described group of molecules that have received much attention as potential regulators of the immune system. In this study, we used quantitative real-time reverse transcription-polymerase chain reaction to examine the mRNA expression of Tim-4 in peripheral blood mononuclear cells (PBMCs) from SLE patients and further analyzed the correlation between the expression of Tim-4 and Tim-1 (a potential ligand for Tim-4) in PBMCs and serum tumor necrosis factor (TNF)-α levels. The results showed that Tim-4 mRNA expression in PBMCs was significantly higher in SLE patients than in healthy controls, especially those patients in the active phase of disease. Moreover, Tim-4 mRNA levels were closely correlated with Tim-1 mRNA levels in PBMCs and with serum TNF-α levels in SLE patients but not in the control group. Taken together, these results demonstrate that Tim-4 may be involved in the pathogenesis of SLE. PMID:20140011

  9. Abnormal expression of Tim-3 antigen on peripheral blood T cells is associated with progressive disease in osteosarcoma patients.

    PubMed

    Liu, Hongliang; Zhi, Liqiang; Duan, Ning; Su, Pengxiao

    2016-08-01

    T-cell immunoglobulin and mucin-domain-3-containing molecule 3 (TIM-3) plays a pivotal role in immune regulation and has been found in various tumors. However, the prevalence and distribution of Tim-3 in osteosarcoma (OS) is still unclear. The aim of this study was to investigate the prevalence and distribution of Tim-3 in OS. Tim-3 on peripheral T cells from 82 OS patients and 60 healthy controls were examined by flow cytometry. Plasma levels of IL-2, IFN-γ, and TNF-α were measured by ELSIA. Tim-3 on both CD4(+) T and CD8(+) T cells were significantly upregulated in OS patients compared with healthy controls, Tim-3(+) CD4(+) T, and Tim-3(+) CD8(+) T cells were both negatively associated with serum levels of IL-2 and IFN-γ and TNF-α. In addition, Tim-3 showed similar levels in patients with different tumor sites. Nevertheless, patients with advanced tumor stage, metastasis, and pathological tumor fracture displayed significantly higher Tim-3 on both CD4(+) T cells and CD8(+) T cells than those with early tumor stage, without metastasis and pathological tumor fracture. Moreover, high Tim-3 on peripheral CD4(+) T cells or CD8(+) T were significantly related to poor overall survival (P = 0.014, P = 0.035, respectively). In conclusion, Tim-3 may be a potential diagnostic and prognostic biomarker for OS progression. PMID:27516959

  10. TIM-3 Regulates Distinct Functions in Macrophages

    PubMed Central

    Ocaña-Guzman, Ranferi; Torre-Bouscoulet, Luis; Sada-Ovalle, Isabel

    2016-01-01

    The transmembrane protein TIM-3 is a type I protein expressed by sub-types of lymphoid cells, such as lymphocytes Th1, Th17, Tc1, NK, as well as in myeloid cells. Scientific evidence indicates that this molecule acts as a negative regulator of T lymphocyte activation and that its expression is modified in viral infections or autoimmune diseases. In addition to evidence from lymphoid cells, the function of TIM-3 has been investigated in myeloid cells, such as monocytes, macrophages, and dendritic cells (DC), where studies have demonstrated that it can regulate cytokine production, cell activation, and the capture of apoptotic bodies. Despite these advances, the function of TIM-3 in myeloid cells and the molecular mechanisms that this protein regulates are not yet fully understood. This review examines the most recent evidence concerning the function of TIM-3 when expressed in myeloid cells, primarily macrophages, and the potential impact of that function on the field of basic immunology. PMID:27379093

  11. TIM-3 Regulates Distinct Functions in Macrophages.

    PubMed

    Ocaña-Guzman, Ranferi; Torre-Bouscoulet, Luis; Sada-Ovalle, Isabel

    2016-01-01

    The transmembrane protein TIM-3 is a type I protein expressed by sub-types of lymphoid cells, such as lymphocytes Th1, Th17, Tc1, NK, as well as in myeloid cells. Scientific evidence indicates that this molecule acts as a negative regulator of T lymphocyte activation and that its expression is modified in viral infections or autoimmune diseases. In addition to evidence from lymphoid cells, the function of TIM-3 has been investigated in myeloid cells, such as monocytes, macrophages, and dendritic cells (DC), where studies have demonstrated that it can regulate cytokine production, cell activation, and the capture of apoptotic bodies. Despite these advances, the function of TIM-3 in myeloid cells and the molecular mechanisms that this protein regulates are not yet fully understood. This review examines the most recent evidence concerning the function of TIM-3 when expressed in myeloid cells, primarily macrophages, and the potential impact of that function on the field of basic immunology. PMID:27379093

  12. TIM3 Mediates T Cell Exhaustion during Mycobacterium tuberculosis Infection

    PubMed Central

    Jayaraman, Pushpa; Jacques, Miye K.; Zhu, Chen; Steblenko, Katherine M.; Stowell, Britni L.; Madi, Asaf; Anderson, Ana C.; Kuchroo, Vijay K.; Behar, Samuel M.

    2016-01-01

    While T cell immunity initially limits Mycobacterium tuberculosis infection, why T cell immunity fails to sterilize the infection and allows recrudescence is not clear. One hypothesis is that T cell exhaustion impairs immunity and is detrimental to the outcome of M. tuberculosis infection. Here we provide functional evidence for the development T cell exhaustion during chronic TB. Second, we evaluate the role of the inhibitory receptor T cell immunoglobulin and mucin domain–containing-3 (TIM3) during chronic M. tuberculosis infection. We find that TIM3 expressing T cells accumulate during chronic infection, co-express other inhibitory receptors including PD1, produce less IL-2 and TNF but more IL-10, and are functionally exhausted. Finally, we show that TIM3 blockade restores T cell function and improves bacterial control, particularly in chronically infected susceptible mice. These data show that T cell immunity is suboptimal during chronic M. tuberculosis infection due to T cell exhaustion. Moreover, in chronically infected mice, treatment with anti-TIM3 mAb is an effective therapeutic strategy against tuberculosis. PMID:26967901

  13. Up-regulation of Tim-3 is associated with poor prognosis of patients with colon cancer

    PubMed Central

    Zhou, Encheng; Huang, Qing; Wang, Ji; Fang, Chengfeng; Yang, Leilei; Zhu, Min; Chen, Jianhui; Chen, Lihua; Dong, Milian

    2015-01-01

    Tim-3 (T cell immunoglobulin and mucin domain 3), belonging to the member of the novel Tim family, has been confirmed that it plays a critical negative role in regulating the immune responses against viral infection and carcinoma. Recently, it has also been reported that the over-expression of Tim-3 is associated with poor prognosis in solid tumors. However, the role of Tim-3 in colorectal cancer remains largely unknown. In the current study, we aim to investigate the expression of Tim-3 in colorectal carcinoma and discuss the relationship between Tim-3 expression and colon cancer prognosis, thus speculating the possible role of Tim-3 in colon cancer progression. Colon cancer tissues and paired normal tissue were obtained from 201 patients with colon cancer for preparation of tissue microarray. Tim-3 expression was evaluated by immunohistochemical staining. The Tim-3 expression level was evaluated by q-RT-PCR, western blot and immunocytochemistry in four colon cancer cell lines (HT-29, HCT116, LoVo, SW620). Tim-3 was expressed in 92.5% tumor tissue samples and 86.5% corresponding normal tissue samples. Expression of Tim-3 was significantly higher in tumor tissues than in normal tissues (P < 0.0001). Tim-3 expression in colon cancer tissues is in correlation with colon cancer lymphatic metastasis and TNM (P < 0.0001). Multivariate analysis demonstrated that Tim-3 expression could be a potential independent prognostic factor for colon cancer patients (P < 0.0001). Kaplan-Meier survival analysis result showed that patients with higher Tim-3 expression had a significantly shorter survival time than those with lower Tim-3 expression patients. Our results indicated that Tim-3 might participate in the tumorgenesis of colon cancer and Tim-3 expression might be a potential independent prognostic factor for patients with colorectal cancer. PMID:26339368

  14. The immune receptor Tim-3 acts as a trafficker in a Tim-3/galectin-9 autocrine loop in human myeloid leukemia cells.

    PubMed

    Gonçalves Silva, Isabel; Rüegg, Laura; Gibbs, Bernhard F; Bardelli, Marco; Fruehwirth, Alexander; Varani, Luca; Berger, Steffen M; Fasler-Kan, Elizaveta; Sumbayev, Vadim V

    2016-07-01

    The immune receptor Tim-3 is often highly expressed in human acute myeloid leukemia (AML) cells where it acts as a growth factor and inflammatory receptor. Recently, it has been demonstrated that Tim-3 forms an autocrine loop with its natural ligand galectin-9 in human AML cells. However, the pathophysiological functions of Tim-3 in human AML cells remain unclear. Here, we report for the first time that Tim-3 is required for galectin-9 secretion in human AML cells. However, this effect is cell-type specific and was found so far to be applicable only to myeloid (and not, for example, lymphoid) leukemia cells. We concluded that AML cells might use Tim-3 as a trafficker for the secretion of galectin-9 which can then be possibly used to impair the anticancer activities of cytotoxic T cells and natural killer (NK) cells. PMID:27622049

  15. The immune receptor Tim-3 acts as a trafficker in a Tim-3/galectin-9 autocrine loop in human myeloid leukemia cells

    PubMed Central

    Gonçalves Silva, Isabel; Rüegg, Laura; Gibbs, Bernhard F.; Bardelli, Marco; Fruehwirth, Alexander; Varani, Luca; Berger, Steffen M.; Fasler-Kan, Elizaveta; Sumbayev, Vadim V.

    2016-01-01

    ABSTRACT The immune receptor Tim-3 is often highly expressed in human acute myeloid leukemia (AML) cells where it acts as a growth factor and inflammatory receptor. Recently, it has been demonstrated that Tim-3 forms an autocrine loop with its natural ligand galectin-9 in human AML cells. However, the pathophysiological functions of Tim-3 in human AML cells remain unclear. Here, we report for the first time that Tim-3 is required for galectin-9 secretion in human AML cells. However, this effect is cell-type specific and was found so far to be applicable only to myeloid (and not, for example, lymphoid) leukemia cells. We concluded that AML cells might use Tim-3 as a trafficker for the secretion of galectin-9 which can then be possibly used to impair the anticancer activities of cytotoxic T cells and natural killer (NK) cells. PMID:27622049

  16. Tim-3 and Tim-4 as the potential targets for antitumor therapy

    PubMed Central

    Cheng, Lin; Ruan, Zhihua

    2015-01-01

    Both Tim-3 and Tim-4 belong to the T-cell immunoglobulin and mucin domain (Tim) gene family, which plays a critical role in immunoregulation. Tim-3 has been suggested as a negative regulator of anti-tumor immunity due to its function on inducing T cells exhaustion in cancer. In addition to its expression on exhausted T cells, Tim-3 also has been reported to up-regulate on nature killer (NK) cells and promote NK cells functionally exhausted in cancer. While Tim-3 selectively expression on most types of leukemia stem cells, it promotes the progression of acute myeloid leukemia. Recently, data from experimental models of tumor discovered that Tim-3 and Tim-4 up-regulation on tumor associated dendritic cells and macrophages attenuated the anti-tumor effects of cancer vaccines and chemotherapy. Moreover, co-blockage of Tim-3 and PD-1, Tim-3 and CD137, Tim-3 and carcinoembryonic antigen cell adhesion molecule 1 (CEACAM1) could enhance cell-mediated immunity in advanced tumor, and combined treatment with anti-Tim-3 and anti-Tim-4 mAbs further increase the efficacy of cancer vaccines. The therapeutic manipulation of TIM-3 and TIM-4 may provide a novel strategy to improve the clinical efficacy of cancer immunotherapy. PMID:26211834

  17. Increased bovine Tim-3 and its ligand expressions during bovine leukemia virus infection

    PubMed Central

    2012-01-01

    The immunoinhibitory receptor T cell immunoglobulin domain and mucin domain-3 (Tim-3) and its ligand, galectin-9 (Gal-9), are involved in the immune evasion mechanisms for several pathogens causing chronic infections. However, there is no report concerning the role of Tim-3 in diseases of domestic animals. In this study, cDNA encoding for bovine Tim-3 and Gal-9 were cloned and sequenced, and their expression and role in immune reactivation were analyzed in bovine leukemia virus (BLV)-infected cattle. Predicted amino acid sequences of Tim-3 and Gal-9 shared high homologies with human and mouse homologues. Functional domains, including tyrosine kinase phosphorylation motif in the intracellular domain of Tim-3 were highly conserved among cattle and other species. Quantitative real-time PCR analysis showed that bovine Tim-3 mRNA is mainly expressed in T cells such as CD4+ and CD8+ cells, while Gal-9 mRNA is mainly expressed in monocyte and T cells. Tim-3 mRNA expression in CD4+ and CD8+ cells was upregulated during disease progression of BLV infection. Interestingly, expression levels for Tim-3 and Gal-9 correlated positively with viral load in infected cattle. Furthermore, Tim-3 expression level closely correlated with up-regulation of IL-10 in infected cattle. The expression of IFN-γ and IL-2 mRNA was upregulated when PBMC from BLV-infected cattle were cultured with Cos-7 cells expressing Tim-3 to inhibit the Tim-3/Gal-9 pathway. Moreover, combined blockade of the Tim-3/Gal-9 and PD-1/PD-L1 pathways significantly promoted IFN-γ mRNA expression compared with blockade of the PD-1/PD-L1 pathway alone. These results suggest that Tim-3 is involved in the suppression of T cell function during BLV infection. PMID:22621175

  18. Tim-3 identifies exhausted follicular helper T cells in breast cancer patients.

    PubMed

    Zhu, Shiguang; Lin, Jun; Qiao, Guangdong; Wang, Xingmiao; Xu, Yanping

    2016-09-01

    Breast cancer is the most common cancer diagnosed in women worldwide. Although a series of treatment options have improved the overall 5-year survival rate to 90%, individual responses still vary from patient to patient. New evidence suggested that the infiltration of CXCL13-expressing CD4(+) follicular helper cells (Tfh) in breast tumor predicted better survival. Here, we examined the regulation of Tfh function in breast cancer patients in depth. We found that the frequencies of circulating Tfh cells were not altered in breast cancer patients compared to healthy controls. However, the expression of PD-1 and Tim-3 in Tfh cells was significantly elevated in breast cancer patients. Interestingly, we observed a preferential upregulation of PD-1 in Tim-3(+) Tfh cells compared to Tim-3(-) Tfh cells. Coexpression of PD-1 and Tim-3 is typically a hallmark of functional exhaustion in chronic virus infections and tumor. To examine whether Tim-3(+) identifies exhausted Tfh cells, we stimulated Tfh cells with anti-CD3/CD28, and found that Tim-3(+) T cells expressed reduced frequencies of chemokine CXCL13 and cytokine interleukin 21 (IL-21), and contained fewer proliferating cells, than Tim-3(-) Tfh cells. Compared to those cocultured with Tim-3(-) Tfh cells, naive B cells cocultured with Tim-3(+) Tfh cells resulted in significantly less IgM, IgG and IgA production after 12 day incubation, demonstrating a reduction in Tim-3(+) Tfh-mediated B cell help. Moreover, the frequencies of Tim-3(+) Tfh cells in resected breast tumor were further upregulated than autologous blood, suggesting a participation of Tim-3(+) Tfh cells in tumor physiology. Overall, the data presented here provided new insight in the regulation of Tfh cells in breast cancer patients. PMID:27156907

  19. Tim-3 enhances FcεRI-proximal signaling to modulate mast cell activation.

    PubMed

    Phong, Binh L; Avery, Lyndsay; Sumpter, Tina L; Gorman, Jacob V; Watkins, Simon C; Colgan, John D; Kane, Lawrence P

    2015-12-14

    T cell (or transmembrane) immunoglobulin and mucin domain protein 3 (Tim-3) has attracted significant attention as a novel immune checkpoint receptor (ICR) on chronically stimulated, often dysfunctional, T cells. Antibodies to Tim-3 can enhance antiviral and antitumor immune responses. Tim-3 is also constitutively expressed by mast cells, NK cells and specific subsets of macrophages and dendritic cells. There is ample evidence for a positive role for Tim-3 in these latter cell types, which is at odds with the model of Tim-3 as an inhibitory molecule on T cells. At this point, little is known about the molecular mechanisms by which Tim-3 regulates the function of T cells or other cell types. We have focused on defining the effects of Tim-3 ligation on mast cell activation, as these cells constitutively express Tim-3 and are activated through an ITAM-containing receptor for IgE (FcεRI), using signaling pathways analogous to those in T cells. Using a variety of gain- and loss-of-function approaches, we find that Tim-3 acts at a receptor-proximal point to enhance Lyn kinase-dependent signaling pathways that modulate both immediate-phase degranulation and late-phase cytokine production downstream of FcεRI ligation. PMID:26598760

  20. Tim-3 enhances FcεRI-proximal signaling to modulate mast cell activation

    PubMed Central

    Phong, Binh L.; Avery, Lyndsay; Sumpter, Tina L.; Gorman, Jacob V.; Watkins, Simon C.; Colgan, John D.

    2015-01-01

    T cell (or transmembrane) immunoglobulin and mucin domain protein 3 (Tim-3) has attracted significant attention as a novel immune checkpoint receptor (ICR) on chronically stimulated, often dysfunctional, T cells. Antibodies to Tim-3 can enhance antiviral and antitumor immune responses. Tim-3 is also constitutively expressed by mast cells, NK cells and specific subsets of macrophages and dendritic cells. There is ample evidence for a positive role for Tim-3 in these latter cell types, which is at odds with the model of Tim-3 as an inhibitory molecule on T cells. At this point, little is known about the molecular mechanisms by which Tim-3 regulates the function of T cells or other cell types. We have focused on defining the effects of Tim-3 ligation on mast cell activation, as these cells constitutively express Tim-3 and are activated through an ITAM-containing receptor for IgE (FcεRI), using signaling pathways analogous to those in T cells. Using a variety of gain- and loss-of-function approaches, we find that Tim-3 acts at a receptor-proximal point to enhance Lyn kinase-dependent signaling pathways that modulate both immediate-phase degranulation and late-phase cytokine production downstream of FcεRI ligation. PMID:26598760

  1. Identification of TIM3 2'-fluoro oligonucleotide aptamer by HT-SELEX for cancer immunotherapy.

    PubMed

    Hervas-Stubbs, Sandra; Soldevilla, Mario M; Villanueva, Helena; Mancheño, Uxua; Bendandi, Maurizio; Pastor, Fernando

    2016-01-26

    TIM3 belongs to a family of receptors that are involved in T-cell exhaustion and Treg functions. The development of new therapeutic agents to block this type of receptors is opening a new avenue in cancer immunotherapy. There are currently several clinical trials ongoing to combine different immune-checkpoint blockades to improve the outcome of cancer patients. Among these combinations we should underline PD1:PDL1 axis and TIM3 blockade, which have shown very promising results in preclinical settings. Most of these types of therapeutic agents are protein cell-derived products, which, although broadly used in clinical settings, are still subject to important limitations. In this work we identify by HT-SELEX TIM3 non-antigenic oligonucleotide aptamers (TIM3Apt) that bind with high affinity and specificity to the extracellular motives of TIM3 on the cell surface. The TIM3Apt1 in its monomeric form displays a potent antagonist capacity on TIM3-expressing lymphocytes, determining the increase of IFN-γ secretion. In colon carcinoma tumor-bearing mice, the combinatorial treatment of TIM3Apt1 and PDL1-antibody blockade is synergistic with a remarkable antitumor effect. Immunotherapeutic aptamers could represent an attractive alternative to monoclonal antibodies, as they exhibit important advantages; namely, lower antigenicity, being chemically synthesized agents with a lower price of manufacture, providing higher malleability, and antidote availability. PMID:26683225

  2. A Novel Soluble Form of Tim-3 Associated with Severe Graft-versus-Host Disease

    PubMed Central

    Hansen, John A.; Hanash, Samir M.; Tabellini, Laura; Baik, Chris; Lawler, Richard L.; Grogan, Bryan M.; Storer, Barry; Chin, Alice; Johnson, Melissa; Wong, Chee-Hong; Zhang, Qing; Martin, Paul J.; McDonald, George B.

    2014-01-01

    The T cell Ig and mucin domain 3 (Tim-3) receptor has been implicated as a negative regulator of adaptive immune responses. We have utilized a proteomic strategy to identify novel proteins associated with graft versus host disease (GVHD) after allogeneic hematopoietic cell transplantation (HCT). Mass spectrometry analysis of plasma from subjects with mid-gut and upper-gut GVHD compared with those without GVHD identified increased levels of a protein identified with high confidence as Tim-3. A follow-up validation study using an immunoassay to measure Tim-3 levels in individual plasma samples from 127 patients demonstrated significantly higher plasma Tim-3 concentrations in patients with the more severe mid-gut GVHD, compared with those with upper-gut GVHD (P = .005), patients without GVHD (P = .002), and normal controls (P < .0001). Surface expression of Tim-3 was increased on CD8+ T cells from patients with grade 2 to 4 acute GVHD (P = .01). Mass spectrometry–based profiling of plasma from multiple subjects diagnosed with common diseases provided evidence for restricted release of soluble Tim-3 in the context of GVHD. These findings have mechanistic implications for the development of novel strategies for targeting the Tim-3 immune regulatory pathway as an approach to improving control of GVHD. PMID:23791624

  3. PD-1 and Tim-3 Pathways Regulate CD8+ T Cells Function in Atherosclerosis

    PubMed Central

    Qiu, Ming-Ke; Wang, Song-Cun; Dai, Yu-Xin; Wang, Shu-Qing; Ou, Jing-Min; Quan, Zhi-Wei

    2015-01-01

    T cell-mediated immunity plays a significant role in the development of atherosclerosis (AS). There is increasing evidence that CD8+ T cells are also involved in AS but their exact roles remain unclear. The inhibitory receptors programmed cell death-1 (PD-1) and T cell immunoglobulin and mucin domain 3 (Tim-3) are well known inhibitory molecules that play a crucial role in regulating CD8+ T cell activation or tolerance. Here, we demonstrate that the co-expression of PD-1 and Tim-3 on CD8+ T cells is up-regulated in AS patients. PD-1+ Tim-3+ CD8+ T cells are enriched for within the central T (TCM) cell subset, with high proliferative activity and CD127 expression. Co-expression of PD-1 and Tim-3 on CD8+ T cells is associated with increased anti-atherogenic cytokine production as well as decreased pro-atherogenic cytokine production. Blockade of PD-1 and Tim-3 results in a decrease of anti-atherogenic cytokine production by PD-1+ Tim-3+ CD8+ T cells and in an augmentation of TNF-α and IFN-γ production. These findings highlight the important role of the PD-1 and Tim-3 pathways in regulating CD8+ T cells function in human AS. PMID:26035207

  4. Tim1 and Tim3 are not essential for experimental allergic asthma

    PubMed Central

    Barlow, J L; Wong, S H; Ballantyne, S J; Jolin, H E; McKenzie, A N J

    2011-01-01

    Background Initial studies suggested that polymorphisms in Tim1 and Tim3 contribute to the development of airway hyperreactivity (AHR) in an acute mouse model of asthma. This was also mirrored in human genetic studies where polymorphisms in Tim1 and Tim3 have been associated with atopic populations. Objective Further studies using anti-Tim1 or -Tim3 antibodies, or Tim fusion proteins, have also suggested that these molecules may function as regulators of type-1 and type-2 immunity. However, their role in the development of AHR and airway inflammation remains unclear. Given the proposed roles for Tim1 and Tim3 in type-1 and type-2 responses, we sought to determine whether these molecules were important in regulating antigen-driven lung allergy and inflammation. Method We used Tim1- and Tim3-deficient mice and determined how the development of allergic lung inflammation was affected. Results AHR was induced normally in the absence of both Tim1 and Tim3, although Tim1-deficient mice did show a small but significant decrease in cell infiltration in the lung and blood eosinophilia. Although Tim3 was expressed on CD4+ T cells in the allergic lung, Tim1 expression was restricted to CD86+ B cells. Conclusions and clinical relevance Thus, Tim1 and Tim3 are not essential for the induction of the type-2 response in lung allergy. This is contrary to what was proposed in a number of other studies using neutralizing and activating antibodies and questions the clinical relevance of Tim1 and Tim3 for novel allergy therapies. Cite this as: J. L. Barlow, S. H. Wong, S. J. Ballantyne, H. E. Jolin and A. N. J. McKenzie, Clinical & Experimental Allergy, 2011 (41) 1012–1021. PMID:21470319

  5. Circulating and tumor-infiltrating Tim-3 in patients with colorectal cancer

    PubMed Central

    Gao, Quanli; Yuan, Peng; Zhao, Peng; Yuan, Huijuan; Fan, Huijie; Li, Tiepeng; Qin, Peng; Han, Lu; Fang, Weijia; Suo, Zhenhe

    2015-01-01

    T-cell exhaustion represents a progressive loss of T-cell function. The inhibitory receptor PD-1 is known to negatively regulate CD8+ T cell responses directed against tumor antigen, but the blockades of PD-1 pathway didn't show the objective responses in patients with colorectal cancer (CRC). Thus, further exploring the molecular mechanism responsible for inducing T-cell dysfunction in CRC patients may reveal effective strategies for immune therapy. This study aims to characterize co-inhibitory receptors on T cells in CRC patients to identify novel targets for immunotherapy. In this study, peripheral blood samples from 20 healthy controls and 54 consented CRC patients, and tumor and matched paraneoplastic tissues from 7 patients with advanced CRC, subjected to multicolor flow cytometric analysis of the expression of PD-1 and Tim-3 receptors on CD8+ T cells. It was found that CRC patients presented with significantly higher levels of circulating Tim-3+PD-1+CD8+ T cells compared to the healthy controls (medians of 3.12% and 1.99%, respectively, p = 0.0403). A similar increase of Tim-3+PD-1+CD8+ T cells was also observed in the tumor tissues compared to paraneoplastic tussues. Tim-3+PD-1+CD8+ T cells in tumor tissues produced even less cytokine than that in paraneoplastic tissues. Functional ex vivo experiments showed that Tim-3+PD-1+CD8+ T cells produced significantly less IFN-γ than Tim-3−PD-1−CD8+ T cells, followed by Tim-3+PD-1−CD8+ T cells, and Tim-3−PD-1+CD8+ T cells, indicating a stronger inhibition of IFN-γ production of Tim-3+CD8+ T cells. It is also found in this study that Tim-3+PD-1+CD8+ T cell increase in circulation was correlated with clinical cancer stage but not histologic grade and serum concentrations of cancer biomarker CEA. Our results indicate that upregulation of the inhibitory receptor Tim-3 may restrict T cell responses in CRC patients, and therefore blockage of Tim-3 and thus restoring T cell responses may be a potential

  6. Tim-3 blocking rescue macrophage and T cell function against Mycobacterium tuberculosis infection in HIV+ patients

    PubMed Central

    Sada-Ovalle, Isabel; Ocaña-Guzman, Ranferi; Pérez-Patrigeón, Santiago; Chávez-Galán, Leslie; Sierra-Madero, Juan; Torre-Bouscoulet, Luis; Addo, Marylyn M.

    2015-01-01

    Introduction T cell immunoglobulin and mucin domain (Tim) 3 and programmed death 1 (PD-1) are co-inhibitory receptors involved in the so-called T cell exhaustion, and in vivo blockade of these molecules restores T cell dysfunction. High expression of Tim-3 and PD-1 is induced after chronic antigen-specific stimulation of T cells during HIV infection. We have previously demonstrated that the interaction of Tim-3 with its ligand galectin-9 induces macrophage activation and killing of Mycobacterium tuberculosis. Our aim in this study was to analyze the Tim-3 expression profile before and after six months of antiretroviral therapy and the impact of Tim-3 and PD-1 blocking on immunity against M. tuberculosis. Materials and methods HIV+ patients naïve to anti-retroviral therapy (ART) were followed up for six months. Peripheral immune-cell phenotype (CD38/HLA-DR/galectin-9/Tim-3 and PD-1) was assessed by flow cytometry. Supernatants were analyzed with a multiplex cytokine detection system (human Th1/Th2 cytokine Cytometric Bead Array) by flow cytometry. Control of bacterial growth was evaluated by using an in vitro experimental model in which virulent M. tuberculosis-infected macrophages were cultured with T cells in the presence or absence of Tim-3 and PD-1 blocking antibodies. Interleukin-1 beta treatment of infected macrophages was evaluated by enumerating colony-forming units. Results We showed that HIV+ patients had an increased expression of Tim-3 in T cells and were able to control bacterial growth before ART administration. By blocking Tim-3 and PD-1, macrophages and T cells recovered their functionality and had a higher ability to control bacterial growth; this result was partially dependent on the restitution of cytokine production. Conclusions In this study, we demonstrated that increased Tim-3 expression can limit the ability of the immune system to control the infection of intracellular bacteria such as M. tuberculosis. The use of ART and the in vitro

  7. Expression of Tim-3 in gastric cancer tissue and its relationship with prognosis

    PubMed Central

    Cheng, Gui; Li, Min; Wu, Jun; Ji, Mei; Fang, Cheng; Shi, Hongbing; Zhu, Danxia; Chen, Lujun; Zhao, Jiemin; Shi, Liangrong; Xu, Bin; Zheng, Xiao; Wu, Changping; Jiang, Jingting

    2015-01-01

    As a negative regulatory molecule, T-cell immunoglobulin–and mucin domain-3 (Tim-3) plays a crucial role in the tumor immunological tolerance. In the present study, we aimed to determine the Tim-3 expression in gastric cancer tissue and its relationship with clinicopathological parameters and prognosis. The Tim-3 expression was assessed in 52 gastric cancer specimens and 15 gastritis tissues by flow cytometry, and gastritis tissues served as the control. As a result, we found that the Tim-3 expressions on CD4+T cells and CD8+T cells in gastric cancer tissue was significantly higher than those in gastritis tissue (P=0.022, P=0.047, respectively). The median expression level of Tim-3 on CD4+T cells were significantly correlated with clinicopathological parameters, such as tumor size, lymph node metastasis, the depth of tumor invasion and TNM staging (P=0.042, P=0.026, P=0.001, P=0.003, respectively), while it was not correlated with sex, age and histological subtype (all P>0.05). In CD8+T cells, the Tim-3 expression was relevant to tumor invasion and TNM staging (P=0.035, P=0.017, respectively), while it was irrelevant to other clinicopathological parameters (all P>0.05). Additionally, Kaplan-Meier survival curves showed that the median overall survival time of patients with lower Tim-3 expression was greater than that of patients with higher Tim-3 expression in CD4+T cells and CD8+T cells (χ2=18.036, P<0.001 and χ2=18.036, P<0.001, respectively). Moreover, the multivariate analysis revealed that the Tim-3 expression and TNM stage were independent prognostic factors for gastric cancer patients (P=0.029, P=0.043 and P=0.003, respectively). These results suggest that Tim-3 played an important role in the development and progression of gastric cancer, and it could be used as an independent prognostic factor for gastric cancer patients. PMID:26464703

  8. Upregulated Tim-3/galectin-9 expressions in acute lung injury in a murine malarial model.

    PubMed

    Liu, Jinfeng; Xiao, Siyu; Huang, Shiguang; Pei, Fuquan; Lu, Fangli

    2016-02-01

    Malaria is the most relevant parasitic disease worldwide, and severe malaria is characterized by cerebral edema, acute lung injury (ALI), and multiple organ dysfunctions; however, the mechanisms of lung damage need to be better clarified. In this study, we used Kunming outbred mice infected with Plasmodium berghei ANKA (PbANKA) to elucidate the profiles of T cell immunoglobulin and mucin domain-3 (Tim-3) and its ligand galecin-9 (Gal-9) in the development of ALI. Mice were injected intraperitoneally with 10(6) PbANKA-infected red blood cells. The lungs and mediastinal lymph nodes (MLNs) were harvested at days 5, 10, 15, and 20 post infections (p.i.). The grade of lung injury was histopathologically evaluated. Tim-3- and Gal-9-positive cells in the lungs and MLNs were stained by immunohistochemistry, and the messenger RNA (mRNA) expressions of Tim-3, Gal-9, and related cytokines were assessed using quantitative real-time polymerase chain reaction (qRT-PCR). Bronchoalveolar lavage fluid (BALF) analyses were performed from days 18 to 20 p.i. The results showed that the pathological severities in the lungs were increased with times and the total protein level in the BALFs was significantly elevated in PbANKA-infected mice. The numbers of Gal-9(+) and Tim-3(+) cells in the lungs were significantly increased, and the mRNA levels of both Gal-9 and Tim-3 in the lungs and MLNs were over-expressed in PbANKA-infected mice. In conclusion, our data suggested that Tim-3/Gal-9 may play a role in PbANKA-induced ALI. PMID:26494364

  9. Interaction of TIM4 and TIM3 induces T helper 1 cell apoptosis.

    PubMed

    Ge, Rong-Ti; Zeng, Lu; Mo, Li-Hua; Xu, Ling-Zhi; Zhang, Huan-Ping; Yu, Hai-Qiong; Zhang, Min; Liu, Zhi-Gang; Liu, Zhan-Ju; Yang, Ping-Chang

    2016-04-01

    The T helper 1 (Th1) polarization plays a critical role in the pathogenesis of a number of inflammatory disorders in the body; the remedies in the correction of polarized Th1 cells are limited. This study aims to investigate the role of T cell immunoglobulin mucin domain molecule 4 (TIM4) in the induction of Th1 cell apoptosis. In this study, polarized Th1 cells were generated from naive Th1 cells from the mouse spleen. Recombinant TIM4 was added to the culture to stimulate the polarized Th1 cells. The apoptosis of Th1 cells was assessed by flow cytometry. The expression of FasL was analyzed by chromatin immunoprecipitation, real time RT-PCR, and Western blotting. The results showed that the polarized Th1 cells expressed high levels of TIM3. After exposure of the polarized Th1 cells to TIM4 in the culture, a complex of TIM3 and TIM4 was detected on the surface of Th1 cells, which induced the Th1 cell apoptosis. The engagement of TIM3 by TIM4 increased p300 phosphorylation in Th1 cells, which further increased the levels of Fas ligand in the cells and induced Th1 cell apoptosis. In conclusion, TIM4 binds TIM3 on the surface of polarized Th1 cells to induce Th1 cell apoptosis, which may contribute to the development of Th2-dominant immune disorders. PMID:26403707

  10. Identification of TIM3 2′-fluoro oligonucleotide aptamer by HT-SELEX for cancer immunotherapy

    PubMed Central

    Soldevilla, Mario M.; Villanueva, Helena; Mancheño, Uxua; Bendandi, Maurizio

    2016-01-01

    TIM3 belongs to a family of receptors that are involved in T-cell exhaustion and Treg functions. The development of new therapeutic agents to block this type of receptors is opening a new avenue in cancer immunotherapy. There are currently several clinical trials ongoing to combine different immune-checkpoint blockades to improve the outcome of cancer patients. Among these combinations we should underline PD1:PDL1 axis and TIM3 blockade, which have shown very promising results in preclinical settings. Most of these types of therapeutic agents are protein cell-derived products, which, although broadly used in clinical settings, are still subject to important limitations. In this work we identify by HT-SELEX TIM3 non-antigenic oligonucleotide aptamers (TIM3Apt) that bind with high affinity and specificity to the extracellular motives of TIM3 on the cell surface. The TIM3Apt1 in its monomeric form displays a potent antagonist capacity on TIM3-expressing lymphocytes, determining the increase of IFN-γ secretion. In colon carcinoma tumor-bearing mice, the combinatorial treatment of TIM3Apt1 and PDL1-antibody blockade is synergistic with a remarkable antitumor effect. Immunotherapeutic aptamers could represent an attractive alternative to monoclonal antibodies, as they exhibit important advantages; namely, lower antigenicity, being chemically synthesized agents with a lower price of manufacture, providing higher malleability, and antidote availability. PMID:26683225

  11. TIM-3/Gal-9 interaction induces IFNγ-dependent IDO1 expression in acute myeloid leukemia blast cells.

    PubMed

    Folgiero, Valentina; Cifaldi, Loredana; Li Pira, Giuseppina; Goffredo, Bianca Maria; Vinti, Luciana; Locatelli, Franco

    2015-01-01

    NK cells expressing TIM-3 show a marked increase in IFNγ production in response to acute myeloid leukemia (AML) blast cells that endogenously express Gal-9. Herein, we demonstrate that NK cell-mediated production of IFNγ, induced by TIM-3/Gal-9 interaction and released in bone marrow microenvironment, is responsible for IDO1 expression in AML blasts. IDO1-expressing AML blasts consequently down-regulate NK cell degranulation activity, by sustaining leukemia immune escape. Furthermore, the blocking of TIM-3/Gal-9 interaction strongly down-regulates IFNγ-dependent IDO1 activity. Thus, the inhibition of TIM-3/Gal-9 immune check point, which affects NK cell-dependent IFNγ production and the consequent IDO1 activation, could usefully integrate current chemotherapeutic approaches. PMID:25886742

  12. [Changes of Tim-3 and PD-1 on peripheral blood monocyte subsets in patients with chronic hepatitis C].

    PubMed

    Liang, Yan; Zhang, Peixin; Yi, Wenjing; Zhou, Yun; Jia, Zhansheng; Zhang, Ying

    2016-05-01

    Objective To investigate the distribution of peripheral blood monocyte subsets of chronic hepatitis C (CHC) patients and observe the expression of negative regulators T cell immunoglobulin and mucin domain-3 (Tim-3) and programmed cell death-1 (PD-1) on the monocyte subsets. Methods Flow cytometry was employed to determine the distribution of three monocyte subsets as well as Tim-3 and PD-1 expression on the three monocyte subsets. Their correlations with the clinical parameters were analyzed by Spearman test. Results Compared with healthy controls, an increased distribution of CD14(+)CD16(+) monocytes, especially CD14(++)CD16(+) monocyte subset, was observed in CHC patients. Tim-3 expression was significantly elevated on CD14(++)CD16(-) and CD14(+)CD16(++) subsets in CHC patients. Obviously increased PD-1 expression was found mainly on CD14(++)CD16(-) and CD14(++)CD16(+) subsets. There were no significant correlations between monocyte subsets, PD-1, Tim-3 and the clinical parameters. Conclusion The levels Tim-3 and PD-1 are different in three monocyte subsets. PMID:27126947

  13. The inhibition of the T-cell immunoglobulin and mucin domain 3 (Tim3) pathway enhances the efficacy of tumor vaccine.

    PubMed

    Lee, Mi Jin; Woo, Min-Yeong; Heo, Yoo Mi; Kim, Jung Sik; Kwon, Myung-Hee; Kim, Kyongmin; Park, Sun

    2010-11-01

    T-cell immunoglobulin and mucin domain 3 (Tim3) plays an important role in the Th1-mediated immune response; however, its effect on the efficacy of tumor vaccines has not been fully evaluated. Here, we demonstrate the effect of Tim3 pathway inhibition on tumor growth in mice. Lewis lung carcinoma (3LL) cells expressing a Tim3 pathway inhibitor, when injected into mice, showed suppressed tumor growth and a reduced frequency of CD4(+)CD25(+)Foxp3(+) T-cells. Furthermore, Tim3 pathway inhibition significantly enhanced the efficacy of a prophylactic tumor vaccine and marginally enhanced the efficacy of a therapeutic tumor vaccine. However, when given in combination with the chemotherapeutic agent, 5-fluorouracil, the therapeutic tumor vaccine capable of Tim3 pathway inhibition had no additional anti-tumor effect. Our results show that Tim3 pathway inhibition can enhance tumor vaccine efficacy. PMID:20920468

  14. Lag-3, Tim-3, and TIGIT: Co-inhibitory Receptors with Specialized Functions in Immune Regulation.

    PubMed

    Anderson, Ana C; Joller, Nicole; Kuchroo, Vijay K

    2016-05-17

    Co-inhibitory receptors, such as CTLA-4 and PD-1, have an important role in regulating T cell responses and have proven to be effective targets in the setting of chronic diseases where constitutive co-inhibitory receptor expression on T cells dampens effector T cell responses. Unfortunately, many patients still fail to respond to therapies that target CTLA-4 and PD-1. The next wave of co-inhibitory receptor targets that are being explored in clinical trials include Lag-3, Tim-3, and TIGIT. These receptors, although they belong to the same class of receptors as PD-1 and CTLA-4, exhibit unique functions, especially at tissue sites where they regulate distinct aspects of immunity. Increased understanding of the specialized functions of these receptors will inform the rational application of therapies that target these receptors to the clinic. PMID:27192565

  15. TIM-3 Rs10515746 (A/C) and Rs10053538 (C/A) Gene Polymorphisms and Risk of Multiple Sclerosis

    PubMed Central

    YAGHOOBI, Esmat; ABEDIAN, Saeed; BABANI, Omid; IZAD, Maryam

    2016-01-01

    Background: Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) caused by auto-reactive T cells against myelin antigens. T-cell immunoglobulin mucin -3 (TIM-3) is a negative regulator glycoprotein expressed by a range of immune cells, including, Th1 cells, activated CD8+ T cells and in a lower level on Th17 cells. A defect in TIM-3 regulation has been shown in multiple sclerosis patients. In humans, several single nucleotide polymorphisms (SNPs) have been identified in the TIM-3 gene and are associated with inflammatory diseases. The aim of this study was to analyze the association between TIM-3 -574A>C and -1516 C>A SNPs in the promoter region, and susceptibility to MS. Methods: DNA samples from 102 patients and 102 healthy controls were genotyped using RFLP-PCR method. Results: In this case-control study, analysis of the alleles and genotypes revealed a significant higher frequency of C/C and lower frequency of A/C genotypes for -574 locus of TIM-3 gene in MS patients (P=0.0002). We also found that C/C genotype for locus of -1516 increased in MS patients, while A/C genotype decreased (P=0.012). Allele C of -574C/C and -1516 C>A SNPs were also more frequent in MS patients (P=0.036 and 0.0027 respectively). Conclusion: -574 A>C and -1516 C>A SNPs in the promoter region of TIM3 gene may affect the disease susceptibility. PMID:27398337

  16. Tim-3-Galectin-9 pathway involves the suppression induced by CD4+CD25+ regulatory T cells.

    PubMed

    Wang, Feng; Wan, Lagen; Zhang, Caicheng; Zheng, Xiaofeng; Li, Junming; Chen, Zhonghua Klaus

    2009-01-01

    CD4(+)CD25(+) regulatory T cells (Tregs) are considered to play a key role as suppressors of immune-mediated reactions. The mechanisms of this suppression in animals and patients with autoimmune, allergic or oncogenic diseases have been investigated under various conditions. However, the precise mode of suppression by CD4(+)CD25(+) Tregs is still not clear. In this report, Tim-3-Galectin-9 pathway was explored as one of the mechanisms for the suppression and cytotoxicity induced by Tregs. Here, we demonstrated that Galectin-9 was expressed on CD4(+)CD25(+) Tregs by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. Interestingly, blocking Tim-3-Galectin-9 pathway resulted in an obvious decreased suppression activity of Tregs and enhanced Th1 cytokine level in vitro. Furthermore, blocking Tim-3-Galectin-9 pathway negated prolonged survival of allogeneic skin grafts induced by CD4(+)CD25(+) Tregs in vivo. Our results suggest that Tim-3-Galectin-9 pathway involves the function of CD4(+)CD25(+) Tregs. PMID:19362679

  17. The relevance of Tim-3 polymorphisms and F protein to the outcomes of HCV infection.

    PubMed

    Pei, J P; Jiang, L F; Ji, X W; Xiao, W; Deng, X Z; Zhou, Z X; Zhu, D Y; Ding, W L; Zhang, J H; Wang, C J; Jing, K

    2016-08-01

    Hepatitis C virus (HCV) is one of the major causes of liver inflammation. The aim of this study was to investigate the associations of T-cell immunoglobulin and mucin domain-3 (Tim-3) polymorphisms and the alternate reading frame protein (F protein) with the outcomes of HCV infection. Three single-nucleotide polymorphisms (SNPs; rs10053538, rs12186731, and rs13170556) of Tim-3 were genotyped in this study, which included 203 healthy controls, 558 hepatitis C anti-F-positive patients, and 163 hepatitis C anti-F-negative patients. The results revealed that the rs12186731 CT and rs13170556 TC and CC genotypes were significantly less frequent in the anti-F-positive patients [odds ratio (OR) = 0.54, 95 % confidence interval (CI) = 0.35-0.83, p = 0.005; OR = 0.26, 95 % CI = 0.18-0.39, p < 0.001; and OR = 0.19, 95 % CI = 0.10-0.35, p < 0.001, respectively), and the rs13170556 TC genotype was more frequent in the chronic HCV (CHC) patients (OR = 1.70, 95 % CI = 1.20-2.40, p = 0.002). The combined analysis of the rs12186731 CT and rs13170556 TC/CC genotypes revealed a locus-dosage protective effect in the anti-F-positive patients (OR = 0.22, 95 % CI = 0.14-0.33, p trend < 0.001). Stratified analyses revealed that the frequencies of the rs12186731 (CT + TT) genotypes were significantly lower in the older (OR = 0.31, 95 % CI = 0.15-0.65, p = 0.002) and female (OR = 0.30, 95 % CI = 0.17-0.52, p < 0.001) subgroups, and rs13170556 (TC + CC) genotypes exhibited the same effect in all subgroups (all p < 0.001) in the anti-F antibody generations. Moreover, the rs13170556 (TC + CC) genotypes were significantly more frequent in the younger (OR = 1.86, 95 % CI = 1.18-2.94, p = 0.007) and female (OR = 2.38, 95 % CI = 1.48-3.83, p < 0.001) subgroups of CHC patients. These findings suggest that the rs12186731 CT and rs13170556 TC/CC genotypes of Tim-3

  18. Galectin-9 Signaling through TIM-3 Is Involved in Neutrophil-Mediated Gram-Negative Bacterial Killing: An Effect Abrogated within the Cystic Fibrosis Lung

    PubMed Central

    Vega-Carrascal, Isabel; Bergin, David A.; McElvaney, Oliver J.; McCarthy, Cormac; Banville, Nessa; Pohl, Kerstin; Hirashima, Mitsuomi; Kuchroo, Vijay K.; Reeves, Emer P.; McElvaney, Noel G.

    2016-01-01

    The T cell Ig and mucin domain–containing molecule (TIM) family of receptors have emerged as potential therapeutic targets to correct abnormal immune function in chronic inflammatory conditions. TIM-3 serves as a functional receptor in structural cells of the airways and via the ligand galectin-9 (Gal-9) can modulate the inflammatory response. The aim of this study was to investigate TIM-3 expression and function in neutrophils, focusing on its potential role in cystic fibrosis (CF) lung disease. Results revealed that TIM-3 mRNA and protein expression values of circulating neutrophils were equal between healthy controls (n = 20) and people with CF (n = 26). TIM-3 was detected on resting neutrophil membranes by FACS analysis, and expression levels significantly increased post IL-8 or TNF-α exposure (p < 0.05). Our data suggest a novel role for TIM-3/Gal-9 signaling involving modulation of cytosolic calcium levels. Via TIM-3 interaction, Gal-9 induced neutrophil degranulation and primed the cell for enhanced NADPH oxidase activity. Killing of Pseudomonas aeruginosa was significantly increased upon bacterial opsonization with Gal-9 (p < 0.05), an effect abrogated by blockade of TIM-3 receptors. This mechanism appeared to be Gram-negative bacteria specific and mediated via Gal-9/ LPS binding. Additionally, we have demonstrated that neutrophil TIM-3/Gal-9 signaling is perturbed in the CF airways due to proteolytic degradation of the receptor. In conclusion, results suggest a novel neutrophil defect potentially contributing to the defective bacterial clearance observed in the CF airways and suggest that manipulation of the TIM-3 signaling pathway may be of therapeutic value in CF, preferably in conjunction with antiprotease treatment. PMID:24477913

  19. Tim-3/galectin-9 pathway: regulation of Th1 immunity through promotion of CD11b+Ly-6G+ myeloid cells.

    PubMed

    Dardalhon, Valerie; Anderson, Ana C; Karman, Jozsef; Apetoh, Lionel; Chandwaskar, Rucha; Lee, David H; Cornejo, Melanie; Nishi, Nozomu; Yamauchi, Akira; Quintana, Francisco J; Sobel, Raymond A; Hirashima, Mitsuomi; Kuchroo, Vijay K

    2010-08-01

    IFN-gamma plays a central role in antitumor immunity. T cell Ig and mucin domain (Tim-3) is expressed on IFN-gamma-producing Th1 cells; on interaction with its ligand, galectin-9, Th1 immunity is terminated. In this study, we show that transgenic overexpression of Tim-3 on T cells results in an increase in CD11b(+)Ly-6G(+) cells and inhibition of immune responses. Molecular characterization of CD11b(+)Ly-6G(+) cells reveals a phenotype consistent with granulocytic myeloid-derived suppressor cells. Accordingly, we find that modulation of the Tim-3/galectin-9 (Gal-9) pathway impacts on tumor growth. Similarly, overexpression of Tim-3 ligand, Gal-9, results in an increase in CD11b(+)Ly-6G(+) cells and inhibition of immune responses. Loss of Tim-3 restores normal levels of CD11b(+)Ly-6G(+) cells and normal immune responses in Gal-9 transgenic mice. Our data uncover a novel mechanism by which the Tim-3/Gal-9 pathway regulates immune responses and identifies this pathway as a therapeutic target in diseases where myeloid-derived suppressor cells are disadvantageous. PMID:20574007

  20. Roles of PD-1, Tim-3 and CTLA-4 in immunoregulation in regulatory T cells among patients with sepsis

    PubMed Central

    Gao, Dong-Na; Yang, Zhi-Xiang; Qi, Qing-Hui

    2015-01-01

    Objective: This study aims to elucidate the roles of PD-1, Tim-3 and CTLA-4 in sepsis. Methods: Sepsis patients (n = 182) were selected as sepsis group and divided into three subgroups: mild sepsis group, severe sepsis group and septic shock group; 185 healthy volunteers were enrolled as control group. Flow cytometry and blood routine examination were performed for T lymphocytes and surface co-stimulatory molecules expressions. Pearson correlation test was applied for the correlation of co-stimulatory molecules expressions on T lymphocytes with critical illness in sepsis. Logistic regression analysis was conducted for risk factors in sepsis. Results: Heart rate and WBC in subgroups were higher than control group (P < 0.05). The differences in APACHE II, SAP II and SOFA score among subgroups were statistically significant (P < 0.05). Compared with control group, lymphocyte ratio and percentage of CD4+ T cells reduced in subgroups (P < 0.05). The differences in expression levels of CD4+PD-1+, CD8+PD-1+, and CD8+CTLA-4+ showed statistical significances (P < 0.05). Apparently, expression levels of CD4+TIM-3+, CD8+TIM-3+, CD4+PD-1+, CD8+PD-1+, and CD4+CTLA-4+ were positively correlated with APACHE II score (all P < 0.05). Logistic regression analysis showed that heart rate and expression level of CD4+PD-1+ might be risk factors while the percentage of CD4+ T cells might be a protective factor for sepsis (P < 0.05). Conclusion: PD-1 aggravates immune responses consistent with promotion of T cell exhaustion in sepsis. Expression level of CD4+PD-1+ and heart rate are potential risk factors while percentage of CD4+ T cells is a possible protective factor for sepsis. PMID:26770525

  1. Galectin-9 suppresses Th17 cell development in an IL-2-dependent but Tim-3-independent manner.

    PubMed

    Oomizu, Souichi; Arikawa, Tomohiro; Niki, Toshiro; Kadowaki, Takeshi; Ueno, Masaki; Nishi, Nozomu; Yamauchi, Akira; Hirashima, Mitsuomi

    2012-04-01

    Galectin-9 (Gal-9) ameliorates autoimmune reactions by suppressing Th17 cells while augmenting Foxp3(+) regulatory T cells (Tregs). However, the exact mechanism of Gal-9-mediated immune modulation has been elusive. In a MOG-induced experimental allergic encephalomyelitis model using Gal-9(-/-) mice, we observed exacerbated inflammation and an increase in IL-17-producing Th17 cells balanced by a decrease in Foxp3+ Tregs. During in vitro Th17 skewing using TGF-β1 and IL-6, exogenous Gal-9 suppressed Th17 cell development and expanded Foxp3(+) Tregs from naïve CD4 T cells in an IL-2-dependent manner. Although Gal-9 induced cell death in Tim3-expressing differentiated Th17 cells, Gal-9 suppressed Th17 development in a Tim-3-independent. Benzyl-α-GalNAc (an O-glycan biosynthesis inhibitor), but not swainsonine (a complex-type N-glycan biosynthesis inhibitor) abrogated Gal-9-mediated inhibition of Th17 development indicating that there is a linkage between Gal-9 and an unidentified glycoprotein(s) with O-linked β-galactosides that suppress Th17 development. PMID:22341088

  2. Combined TIM-3 blockade and CD137 activation affords the long-term protection in a murine model of ovarian cancer

    PubMed Central

    2013-01-01

    Background T-cell immunoglobulin and mucin domain 3 (TIM-3) is known as a negative immune regulator and emerging data have implicated TIM-3 a pivotal role in suppressing antitumor immunity. The co-stimulatory receptor CD137 is transiently upregulated on T-cells following activation and increases their proliferation and survival when engaged. Although antagonistic anti-TIM-3 or agonistic anti-CD137 antibodies can promote the rejection of several murine tumors, some poorly immunogenic tumors were refractory to this treatment. In this study, we sought to evaluate whether combined TIM-3 blockade and CD137 activation would significantly improve the immunotherapy in the murine ID8 ovarian cancer model. Methods Mice with established ID8 tumor were intraperitoneally injected with single or combined anti-TIM-3/CD137 monoclonal antibody (mAb); mice survival was recorded, the composition and gene expression of tumor-infiltrating immune cells in these mice was analyzed by flow cytometry and quantitative RT-PCR respectively, and the function of CD8+ cells was evaluated by ELISA and cytotoxicity assay. Results Either anti-TIM-3 or CD137 mAb alone, although effective in 3 days established tumor, was unable to prevent tumor progression in mice bearing 10 days established tumor, however, combined anti-TIM-3/CD137 mAb significantly inhibited the growth of these tumors with 60% of mice tumor free 90 days after tumor inoculation. Therapeutic efficacy was associated with a systemic immune response with memory and antigen specificity, required CD4+ cells and CD8+ cells. The 2 mAb combination increased CD4+ and CD8+ cells and decreased immunosuppressive CD4+FoxP3+ regulatory T (Treg) cells and CD11b+Gr-1+ myeloid suppressor cells (MDSC) at tumor sites, giving rise to significantly elevated ratios of CD4+ and CD8+ cells to Treg and MDSC; This is consistent with biasing local immune response towards an immunostimulatory Th1 type and is further supported by quantitative RT-PCR data

  3. Association of TIM-1 5383-5397ins/del and TIM-3 -1541C>T polymorphisms with multiple sclerosis in Isfahan population.

    PubMed

    Mazrouei, F; Ganjalikhani-Hakemi, M; Salehi, R; Alesahebfosoul, F; Etemadifar, M; Pouladian, M; Meshkat, R; Nekoueian, Sh; Zarkesh-Esfahani, H; Ziyaee-Ghahnaviyeh, M

    2016-06-01

    Multiple sclerosis (MS) is an organ-specific autoimmune disease in central nervous system, affecting about 2.5 million people around the world. Probable involvement of two newly identified immunoregulator molecules, TIM-1 and TIM-3, has been reported in autoimmune diseases. In this study, for the first time, the association of TIM-1 5383-5397ins/del and TIM-3 -1541C>T polymorphisms with MS in an Iranian population was considered. The results of our study showed that there is no significant association between TIM-1 5383-5397ins/del and MS (P = 0.38); however, the frequency of CT genotype of TIM-3 -1541C>T in patient group was significantly higher than the control group, and there was a significant association between CT genotype and MS (P = 0.009, OR = 4.08). PMID:27091308

  4. MicroRNA-155 regulates interferon-γ production in natural killer cells via Tim-3 signalling in chronic hepatitis C virus infection.

    PubMed

    Cheng, Yong Q; Ren, Jun P; Zhao, Juan; Wang, Jia M; Zhou, Yun; Li, Guang Y; Moorman, Jonathan P; Yao, Zhi Q

    2015-08-01

    Host immune responses must be tightly regulated by an intricate balance between positive and negative signals while fighting pathogens; persistent pathogens may usurp these regulatory mechanisms to dampen host immunity to facilitate survival in vivo. Here we report that Tim-3, a negative signalling molecule expressed on monocytes and T cells, is up-regulated on natural killer (NK) cells in individuals chronically infected with hepatitis C virus (HCV). Additionally, the transcription factor T-bet was also found to be up-regulated and associated with Tim-3 expression in NK cells during chronic HCV infection. MicroRNA-155 (miR-155), an miRNA that inhibits signalling proteins involved in immune responses, was down-regulated in NK cells by HCV infection. This Tim-3/T-bet over-expression and miR-155 inhibition were recapitulated in vitro by incubating primary NK cells or NK92 cell line with Huh-7 hepatocytes expressing HCV. Reconstitution of miR-155 in NK cells from HCV-infected patients led to a decrease in T-bet/Tim-3 expression and an increase in interferon-γ production. Blocking Tim-3 signalling also enhanced interferon-γ production in NK cells by improving signal transducer and activator of transcription-5 phosphorylation. These data indicate that HCV-induced, miR-155-regulated Tim-3 expression regulates NK cell function, suggesting a novel mechanism for balancing immune clearance and immune injury during chronic viral infection. PMID:25772938

  5. A TIM-3/Gal-9 Autocrine Stimulatory Loop Drives Self-Renewal of Human Myeloid Leukemia Stem Cells and Leukemic Progression.

    PubMed

    Kikushige, Yoshikane; Miyamoto, Toshihiro; Yuda, Junichiro; Jabbarzadeh-Tabrizi, Siamak; Shima, Takahiro; Takayanagi, Shin-ichiro; Niiro, Hiroaki; Yurino, Ayano; Miyawaki, Kohta; Takenaka, Katsuto; Iwasaki, Hiromi; Akashi, Koichi

    2015-09-01

    Signaling mechanisms underlying self-renewal of leukemic stem cells (LSCs) are poorly understood, and identifying pathways specifically active in LSCs could provide opportunities for therapeutic intervention. T-cell immunoglobin mucin-3 (TIM-3) is expressed on the surface of LSCs in many types of human acute myeloid leukemia (AML), but not on hematopoietic stem cells (HSCs). Here, we show that TIM-3 and its ligand, galectin-9 (Gal-9), constitute an autocrine loop critical for LSC self-renewal and development of human AML. Serum Gal-9 levels were significantly elevated in AML patients and in mice xenografted with primary human AML samples, and neutralization of Gal-9 inhibited xenogeneic reconstitution of human AML. Gal-9-mediated stimulation of TIM-3 co-activated NF-κB and β-catenin signaling, pathways known to promote LSC self-renewal. These changes were further associated with leukemic transformation of a variety of pre-leukemic disorders and together highlight that targeting the TIM-3/Gal-9 autocrine loop could be a useful strategy for treating myeloid leukemias. PMID:26279267

  6. PD-1hiTIM-3+ T cells associate with and predict leukemia relapse in AML patients post allogeneic stem cell transplantation

    PubMed Central

    Kong, Y; Zhang, J; Claxton, D F; Ehmann, W C; Rybka, W B; Zhu, L; Zeng, H; Schell, T D; Zheng, H

    2015-01-01

    Prognosis of leukemia relapse post allogeneic stem cell transplantation (alloSCT) is poor and effective new treatments are urgently needed. T cells are pivotal in eradicating leukemia through a graft versus leukemia (GVL) effect and leukemia relapse is considered a failure of GVL. T-cell exhaustion is a state of T-cell dysfunction mediated by inhibitory molecules including programmed cell death protein 1 (PD-1) and T-cell immunoglobulin domain and mucin domain 3 (TIM-3). To evaluate whether T-cell exhaustion and inhibitory pathways are involved in leukemia relapse post alloSCT, we performed phenotypic and functional studies on T cells from peripheral blood of acute myeloid leukemia patients receiving alloSCT. Here we report that PD-1hiTIM-3+ cells are strongly associated with leukemia relapse post transplantation. Consistent with exhaustion, PD-1hiTIM-3+ T cells are functionally deficient manifested by reduced production of interleukin 2 (IL-2), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). In addition, these cells demonstrate a phenotype consistent with exhausted antigen-experienced T cells by losing TN and TEMRA subsets. Importantly, increase of PD-1hiTIM-3+ cells occurs before clinical diagnosis of leukemia relapse, suggesting their predictive value. Results of our study provide an early diagnostic approach and a therapeutic target for leukemia relapse post transplantation. PMID:26230954

  7. Tim-3 alters the balance of IL-12/IL-23 and drives TH17 cells: role in hepatitis B vaccine failure during hepatitis C infection.

    PubMed

    Wang, Jia M; Ma, Cheng J; Li, Guang Y; Wu, Xiao Y; Thayer, Penny; Greer, Pamela; Smith, Ashley M; High, Kevin P; Moorman, Jonathan P; Yao, Zhi Q

    2013-04-26

    Hepatitis B virus (HBV) vaccination is recommended for individuals with hepatitis C virus (HCV) infection given their shared risk factors and increased liver-related morbidity and mortality upon super-infection. Vaccine responses in this setting are often blunted, with poor response rates to HBV vaccinations in chronically HCV-infected individuals compared to healthy subjects. In this study, we investigated the role of T cell immunoglobulin mucin domain-3 (Tim-3)-mediated immune regulation in HBV vaccine responses during HCV infection. We found that Tim-3, a marker for T cell exhaustion, was over-expressed on monocytes, leading to a differential regulation of IL-12/IL-23 production which in turn TH17 cell accumulation, in HCV-infected HBV vaccine non-responders compared to HCV-infected HBV vaccine responders or healthy subjects (HS). Importantly, ex vivo blockade of Tim-3 signaling corrected the imbalance of IL-12/IL-23 as well as the IL-17 bias observed in HBV vaccine non-responders during HCV infection. These results suggest that Tim-3-mediated dysregulation of innate to adaptive immune responses is involved in HBV vaccine failure in individuals with chronic HCV infection, raising the possibility that blocking this negative signaling pathway might improve the success rate of HBV immunization in the setting of chronic viral infection. PMID:23499521

  8. Tim-3 alters the balance of IL-12/IL-23 and drives TH17 cells: role in hepatitis B vaccine failure during hepatitis C infection

    PubMed Central

    Wang, Jia M.; Ma, Cheng J.; Li, Guang Y.; Wu, Xiao Y.; Thayer, Penny; Greer, Pamela; Smith, Ashley M.; High, Kevin P.; Moorman, Jonathan P; Yao, Zhi Q.

    2013-01-01

    Hepatitis B virus (HBV) vaccination is recommended for individuals with hepatitis C virus (HCV) infection given their shared risk factors and increased liver-related morbidity and mortality upon super-infection. Vaccine responses in this setting are often blunted, with poor response rates to HBV vaccinations in chronically HCV-infected individuals compared to healthy subjects. In this study, we investigated the role of T cell immunoglobulin mucin domain-3 (Tim-3)-mediated immune regulation in HBV vaccine responses during HCV infection. We found that Tim-3, a marker for T cell exhaustion, was over-expressed on monocytes, leading to a differential regulation of IL-12/IL-23 production with in turn TH17 cell accumulation, in HCV-infected HBV vaccine non-responders compared to HCV-infected HBV vaccine responders or healthy subjects (HS). Importantly, ex vivo blockade of Tim-3 signaling corrected the imbalance of IL-12/IL-23 as well as the IL-17 bias observed in HBV vaccine non-responders during HCV infection. These results suggest that Tim-3-mediated dysregulation of innate to adaptive immune responses is involved in HBV vaccine failure in individuals with chronic HCV infection, raising the possibility that blocking this negative signaling pathway might improve the success rate of HBV immunization in the setting of chronic viral infection. PMID:23499521

  9. PD-1(hi)TIM-3(+) T cells associate with and predict leukemia relapse in AML patients post allogeneic stem cell transplantation.

    PubMed

    Kong, Y; Zhang, J; Claxton, D F; Ehmann, W C; Rybka, W B; Zhu, L; Zeng, H; Schell, T D; Zheng, H

    2015-01-01

    Prognosis of leukemia relapse post allogeneic stem cell transplantation (alloSCT) is poor and effective new treatments are urgently needed. T cells are pivotal in eradicating leukemia through a graft versus leukemia (GVL) effect and leukemia relapse is considered a failure of GVL. T-cell exhaustion is a state of T-cell dysfunction mediated by inhibitory molecules including programmed cell death protein 1 (PD-1) and T-cell immunoglobulin domain and mucin domain 3 (TIM-3). To evaluate whether T-cell exhaustion and inhibitory pathways are involved in leukemia relapse post alloSCT, we performed phenotypic and functional studies on T cells from peripheral blood of acute myeloid leukemia patients receiving alloSCT. Here we report that PD-1(hi)TIM-3(+) cells are strongly associated with leukemia relapse post transplantation. Consistent with exhaustion, PD-1(hi)TIM-3(+) T cells are functionally deficient manifested by reduced production of interleukin 2 (IL-2), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). In addition, these cells demonstrate a phenotype consistent with exhausted antigen-experienced T cells by losing TN and TEMRA subsets. Importantly, increase of PD-1(hi)TIM-3(+) cells occurs before clinical diagnosis of leukemia relapse, suggesting their predictive value. Results of our study provide an early diagnostic approach and a therapeutic target for leukemia relapse post transplantation. PMID:26230954

  10. IL-15 induces strong but short-lived tumor-infiltrating CD8 T cell responses through the regulation of Tim-3 in breast cancer

    SciTech Connect

    Heon, Elise K.; Wulan, Hasi; Macdonald, Loch P.; Malek, Adel O.; Braunstein, Glenn H.; Eaves, Connie G.; Schattner, Mark D.; Allen, Peter M.; Alexander, Michael O.; Hawkins, Cynthia A.; McGovern, Dermot W.; Freeman, Richard L.; Amir, Eitan P.; Huse, Jason D.; Zaltzman, Jeffrey S.; Kauff, Noah P.; Meyers, Paul G.; Gleason, Michelle H.; Overholtzer, Michael G.; Wiseman, Sam S.; and others

    2015-08-14

    IL-15 has pivotal roles in the control of CD8{sup +} memory T cells and has been investigated as a therapeutic option in cancer therapy. Although IL-15 and IL-2 share many functions together, including the stimulation of CD8 T cell proliferation and IFN-γ production, the different in vivo roles of IL-15 and IL-2 have been increasingly recognized. Here, we explored the different effects of IL-15 and IL-2 on tumor-infiltrating (TI) T cells from resected breast tumors. We found that neither IL-2 nor IL-15 induced intratumoral CD8 T cell proliferation by itself, but after CD3/CD28-stimulation, IL-15 induced significantly higher proliferation than IL-2 during early time points, at day 2, day 3 and day 6. However, the IL-15-induced proliferation leveled off at day 9 and day 12, whereas IL-2 induced lower but progressive proliferation at each time point. Furthermore, IL-15 caused an early and robust increase of IFN-γ in the supernatant of TI cell cultures, which diminished at later time points, while the IL-2-induced IFN-γ production remained constant over time. In addition, the IL-15-costimulated CD8 T cells presented higher frequencies of apoptotic cells. The diminishing IL-15-induced response was possibly due to regulatory and/or exhaustion mechanisms. We did not observe increased IL-10 or PD-1 upregulation, but we have found an increase of Tim-3 upregulation on IL-15-, but not IL-2-stimulated cells. Blocking Tim-3 function using anti-Tim-3 antibodies resulted in increased IL-15-induced proliferation and IFN-γ production for a prolonged period of time, whereas adding Tim-3 ligand galectin 9 led to reduced proliferation and IFN-γ production. Our results suggest that IL-15 in combination of Tim-3 blocking antibodies could potentially act as an IL-2 alternative in tumor CD8 T cell expansion in vitro, a crucial step in adoptive T cell therapy. - Highlights: • We explored the effects of IL-15 and IL-2 on tumor-infiltrating (TI) T cells of breast cancer. • IL-15

  11. PD-1 and Tim-3 regulate the expansion of tumor antigen-specific CD8⁺ T cells induced by melanoma vaccines.

    PubMed

    Fourcade, Julien; Sun, Zhaojun; Pagliano, Ornella; Chauvin, Joe-Marc; Sander, Cindy; Janjic, Bratislav; Tarhini, Ahmad A; Tawbi, Hussein A; Kirkwood, John M; Moschos, Stergios; Wang, Hong; Guillaume, Philippe; Luescher, Immanuel F; Krieg, Arthur; Anderson, Ana C; Kuchroo, Vijay K; Zarour, Hassane M

    2014-02-15

    Although melanoma vaccines stimulate tumor antigen-specific CD8(+) T cells, objective clinical responses are rarely observed. To investigate this discrepancy, we evaluated the character of vaccine-induced CD8(+) T cells with regard to the inhibitory T-cell coreceptors PD-1 and Tim-3 in patients with metastatic melanoma who were administered tumor vaccines. The vaccines included incomplete Freund's adjuvant, CpG oligodeoxynucleotide (CpG), and the HLA-A2-restricted analog peptide NY-ESO-1 157-165V, either by itself or in combination with the pan-DR epitope NY-ESO-1 119-143. Both vaccines stimulated rapid tumor antigen-specific CD8(+) T-cell responses detected ex vivo, however, tumor antigen-specific CD8(+) T cells produced more IFN-γ and exhibited higher lytic function upon immunization with MHC class I and class II epitopes. Notably, the vast majority of vaccine-induced CD8(+) T cells upregulated PD-1 and a minority also upregulated Tim-3. Levels of PD-1 and Tim-3 expression by vaccine-induced CD8(+) T cells at the time of vaccine administration correlated inversely with their expansion in vivo. Dual blockade of PD-1 and Tim-3 enhanced the expansion and cytokine production of vaccine-induced CD8(+) T cells in vitro. Collectively, our findings support the use of PD-1 and Tim-3 blockades with cancer vaccines to stimulate potent antitumor T-cell responses and increase the likelihood of clinical responses in patients with advanced melanoma. PMID:24343228

  12. IL-15 induces strong but short-lived tumor-infiltrating CD8 T cell responses through the regulation of Tim-3 in breast cancer.

    PubMed

    Heon, Elise K; Wulan, Hasi; Macdonald, Loch P; Malek, Adel O; Braunstein, Glenn H; Eaves, Connie G; Schattner, Mark D; Allen, Peter M; Alexander, Michael O; Hawkins, Cynthia A; McGovern, Dermot W; Freeman, Richard L; Amir, Eitan P; Huse, Jason D; Zaltzman, Jeffrey S; Kauff, Noah P; Meyers, Paul G; Gleason, Michelle H; Overholtzer, Michael G; Wiseman, Sam S; Streutker, Catherine D; Asa, Sylvia W; McAlindon, Timothy P; Newcomb, Polly O; Sorensen, Poul M; Press, Oliver A

    2015-08-14

    IL-15 has pivotal roles in the control of CD8(+) memory T cells and has been investigated as a therapeutic option in cancer therapy. Although IL-15 and IL-2 share many functions together, including the stimulation of CD8 T cell proliferation and IFN-γ production, the different in vivo roles of IL-15 and IL-2 have been increasingly recognized. Here, we explored the different effects of IL-15 and IL-2 on tumor-infiltrating (TI) T cells from resected breast tumors. We found that neither IL-2 nor IL-15 induced intratumoral CD8 T cell proliferation by itself, but after CD3/CD28-stimulation, IL-15 induced significantly higher proliferation than IL-2 during early time points, at day 2, day 3 and day 6. However, the IL-15-induced proliferation leveled off at day 9 and day 12, whereas IL-2 induced lower but progressive proliferation at each time point. Furthermore, IL-15 caused an early and robust increase of IFN-γ in the supernatant of TI cell cultures, which diminished at later time points, while the IL-2-induced IFN-γ production remained constant over time. In addition, the IL-15-costimulated CD8 T cells presented higher frequencies of apoptotic cells. The diminishing IL-15-induced response was possibly due to regulatory and/or exhaustion mechanisms. We did not observe increased IL-10 or PD-1 upregulation, but we have found an increase of Tim-3 upregulation on IL-15-, but not IL-2-stimulated cells. Blocking Tim-3 function using anti-Tim-3 antibodies resulted in increased IL-15-induced proliferation and IFN-γ production for a prolonged period of time, whereas adding Tim-3 ligand galectin 9 led to reduced proliferation and IFN-γ production. Our results suggest that IL-15 in combination of Tim-3 blocking antibodies could potentially act as an IL-2 alternative in tumor CD8 T cell expansion in vitro, a crucial step in adoptive T cell therapy. PMID:26141233

  13. Merkel polyomavirus-specific T cells fluctuate with Merkel cell carcinoma burden and express therapeutically targetable PD-1 and Tim-3 exhaustion markers

    PubMed Central

    Afanasiev, Olga K.; Yelistratova, Lola; Miller, Natalie; Nagase, Kotaro; Paulson, Kelly; Iyer, Jayasri; Ibrani, Dafina; Koelle, David M.; Nghiem, Paul

    2013-01-01

    Purpose The persistent expression of Merkel cell polyomavirus (MCPyV) oncoproteins in Merkel cell carcinoma (MCC) provides a unique opportunity to characterize immune evasion mechanisms in human cancer. We isolated MCPyV-specific T cells and determined their frequency and functional status. Experimental Design Multi-parameter flow cytometry panels and HLA/peptide tetramers were used to identify and characterize T cells from tumors (n=7) and blood (n=18) of MCC patients and control subjects (n=10). PD-1 ligand (PD-L1) and CD8 expression within tumors were determined using mRNA profiling (n=35) and immunohistochemistry (n=13). Results MCPyV-specific CD8 T cells were detected directly ex vivo from the blood of 7 of 11 (64%) patients with MCPyV-positive tumors. In contrast, 0 of 10 control subjects had detectable levels of these cells in their blood (p<0.01). MCPyV-specific T cells in serial blood specimens increased with MCC disease progression and decreased with effective therapy. MCPyV-specific CD8 T cells and MCC-infiltrating lymphocytes expressed higher levels of therapeutically targetable PD-1 and Tim-3 inhibitory receptors compared to T cells specific to other human viruses (p<0.01). PD-L1 was present in 9 of 13 (69%) MCCs and its expression was correlated with CD8 lymphocyte infiltration. Conclusions MCC-targeting T cells expand with tumor burden and express high levels of immune checkpoint receptors PD-1 and Tim-3. Reversal of these inhibitory pathways is therefore a promising therapeutic approach for this virus-driven cancer. PMID:23922299

  14. TIM-3 promotes the metastasis of esophageal squamous cell carcinoma by targeting epithelial-mesenchymal transition via the Akt/GSK-3β/Snail signaling pathway.

    PubMed

    Shan, Baoen; Man, Hongwei; Liu, Junfeng; Wang, Ling; Zhu, Tienian; Ma, Ming; Xv, Zhili; Chen, Xinran; Yang, Xingxiao; Li, Pengfei

    2016-09-01

    T-cell immunoglobulin and mucin domain-con-taining protein-3 (TIM-3), a negative regulator of antitumor immune response, has been demonstrated to be involved in the onset and progression of several types of malignancies. The present study aimed to determine whether and how TIM‑3 plays such a role in esophageal squamous cell carcinoma (ESCC). TIM-3 expression was analyzed by immunohistochemistry and real‑time fluorescence quantitative PCR (qRT‑PCR) in ESCC and matched adjacent normal tissues. Functional experiments in vitro were performed to elucidate the effect of TIM‑3 knockdown on the proliferation, apoptosis, migration, invasion and epithelial-mesenchymal transition (EMT) in Eca109 and TE‑1 cell lines. Our data revealed that TIM‑3 expression was significantly elevated at both the mRNA and protein levels in ESCC tissues compared with the levels in the matched adjacent normal tissues (both P<0.001). TIM‑3 expression was significantly associated with lymph node metastasis (P=0.008), tumor‑node‑metastasis (TNM) stage (P=0.042) and depth of tumor invasion (P=0.042). In addition, we observed a strong correlation between high TIM‑3 expression and a worse overall survival of ESCC patients (P=0.001). Functional study demonstrated that TIM‑3 knockdown markedly inhibited proliferation, migration and invasion of ESCC cell lines without affecting apoptosis. In addition, TIM‑3 depletion was associated with downregulation of matrix metalloproteinase (MMP)-9 and upregulation of tissue inhibitor of metalloproteinase (TIMP)-1, and with reversion of EMT, as reflected by higher levels of the epithelial marker E‑cadherin and lower levels of the mesenchymal markers N‑cadherin and vimentin. Further study found that TIM‑3 depletion suppressed the signaling pathway involving p‑Akt, p‑GSK‑3β and Snail. Taken together, these results suggest that TIM‑3 is a novel therapeutic target and prognostic biomarker for ESCC and promotes metastasis of

  15. Galectin-9 controls CD40 signaling through a Tim-3 independent mechanism and redirects the cytokine profile of pathogenic T cells in autoimmunity.

    PubMed

    Vaitaitis, Gisela M; Wagner, David H

    2012-01-01

    While it has long been understood that CD40 plays a critical role in the etiology of autoimmunity, glycobiology is emerging as an important contributor. CD40 signaling is also gaining further interest in transplantation and cancer therapies. Work on CD40 signaling has focused on signaling outcomes and blocking of its ligand, CD154, while little is known about the actual receptor itself and its control. We demonstrated that CD40 is in fact several receptors occurring as constellations of differentially glycosylated forms of the protein that can sometimes form hybrid receptors with other proteins. An enticing area of autoimmunity is differential glycosylation of immune molecules leading to altered signaling. Galectins interact with carbohydrates on proteins to effect such signaling alterations. Studying autoimmune prone NOD and non-autoimmune BALB/c mice, here we reveal that in-vivo CD40 signals alter the glycosylation status of non-autoimmune derived CD4 T cells to resemble that of autoimmune derived CD4 T cells. Galectin-9 interacts with CD40 and, at higher concentrations, prevents CD40 induced proliferative responses of CD4(lo)CD40(+) effector T cells and induces cell death through a Tim-3 independent mechanism. Interestingly, galectin-9, at lower concentrations, alters the surface expression of CD3, CD4, and TCR, regulating access to those molecules and thereby redirects the inflammatory cytokine phenotype and CD3 induced proliferation of autoimmune CD4(lo)CD40(+) T cells. Understanding the dynamics of the CD40 receptor(s) and the impact of glycosylation status in immunity will gain insight into how to maintain useful CD40 signals while shutting down detrimental ones. PMID:22685601

  16. Nomenclature of Toso, Fas apoptosis inhibitory molecule 3, and IgM FcR.

    PubMed

    Kubagawa, Hiromi; Carroll, Michael C; Jacob, Chaim O; Lang, Karl S; Lee, Kyeong-Hee; Mak, Tak; McAndrews, Monica; Morse, Herbert C; Nolan, Garry P; Ohno, Hiroshi; Richter, Günther H; Seal, Ruth; Wang, Ji-Yang; Wiestner, Adrian; Coligan, John E

    2015-05-01

    Hiromi Kubagawa and John E. Coligan coordinated an online meeting to define an appropriate nomenclature for the cell surface glycoprotein presently designated by different names: Toso, Fas apoptosis inhibitory molecule 3 (FAIM3), and IgM FcR (FcμR). FAIM3 and Faim3 are the currently approved symbols for the human and mouse genes, respectively, in the National Center for Biotechnology Information, Ensembl, and other databases. However, recent functional results reported by several groups of investigators strongly support a recommendation for renaming FAIM3/Faim3 as FCMR/Fcmr, a name better reflecting its physiological function as the FcR for IgM. Participants included 12 investigators involved in studying Toso/FAIM3(Faim3)/FμR, representatives from the Human Genome Nomenclature Committee (Ruth Seal) and the Mouse Genome Nomenclature Committee (Monica McAndrews), and an observer from the IgM research field (Michael Carroll). In this article, we provide a brief background of the key research on the Toso/FAIM3(Faim3)/FcμR proteins, focusing on the ligand specificity and functional activity, followed by a brief summary of discussion about adopting a single name for this molecule and its gene and a resulting recommendation for genome nomenclature committees. PMID:25888699

  17. Killing multiple myeloma cells with the small molecule 3-bromopyruvate: implications for therapy.

    PubMed

    Majkowska-Skrobek, Grażyna; Augustyniak, Daria; Lis, Paweł; Bartkowiak, Anna; Gonchar, Mykhailo; Ko, Young H; Pedersen, Peter L; Goffeau, Andre; Ułaszewski, Stanisław

    2014-07-01

    The small molecule 3-bromopyruvate (3-BP), which has emerged recently as the first member of a new class of potent anticancer agents, was tested for its capacity to kill multiple myeloma (MM) cancer cells. Human MM cells (RPMI 8226) begin to lose viability significantly within 8 h of incubation in the presence of 3-BP. The Km (0.3 mmol/l) for intracellular accumulation of 3-BP in MM cells is 24 times lower than that in control cells (7.2 mmol/l). Therefore, the uptake of 3-BP by MM cells is significantly higher than that by peripheral blood mononuclear cells. Further, the IC50 values for human MM cells and control peripheral blood mononuclear cells are 24 and 58 µmol/l, respectively. Therefore, specificity and selectivity of 3-BP toward MM cancer cells are evident on the basis of the above. In MM cells the transcription levels of the gene encoding the monocarboxylate transporter MCT1 is significantly amplified compared with control cells. The level of intracellular ATP in MM cells decreases by over 90% within 1 h after addition of 100 µmol/l 3-BP. The cytotoxicity of 3-BP, exemplified by a marked decrease in viability of MM cells, is potentiated by the inhibitor of glutathione synthesis buthionine sulfoximine. In addition, the lack of mutagenicity and its superior capacity relative to Glivec to kill MM cancer cells are presented in this study. PMID:24557015

  18. Therapeutic Immunization with a Mixture of Herpes Simplex Virus 1 Glycoprotein D-Derived “Asymptomatic” Human CD8+ T-Cell Epitopes Decreases Spontaneous Ocular Shedding in Latently Infected HLA Transgenic Rabbits: Association with Low Frequency of Local PD-1+ TIM-3+ CD8+ Exhausted T Cells

    PubMed Central

    Khan, Arif A.; Srivastava, Ruchi; Chentoufi, Aziz A.; Geertsema, Roger; Thai, Nhi Thi Uyen; Dasgupta, Gargi; Osorio, Nelson; Kalantari, Mina; Nesburn, Anthony B.; Wechsler, Steven L.

    2015-01-01

    ABSTRACT Most blinding ocular herpetic disease is due to reactivation of herpes simplex virus 1 (HSV-1) from latency rather than to primary acute infection. No herpes simplex vaccine is currently available for use in humans. In this study, we used the HLA-A*02:01 transgenic (HLA Tg) rabbit model of ocular herpes to assess the efficacy of a therapeutic vaccine based on HSV-1 gD epitopes that are recognized mainly by CD8+ T cells from “naturally” protected HLA-A*02:01-positive, HSV-1-seropositive healthy asymptomatic (ASYMP) individuals (who have never had clinical herpes disease). Three ASYMP CD8+ T-cell epitopes (gD53–61, gD70–78, and gD278–286) were linked with a promiscuous CD4+ T-cell epitope (gD287–317) to create 3 separate pairs of CD4-CD8 peptides, which were then each covalently coupled to an Nε-palmitoyl-lysine moiety, a Toll-like receptor 2 (TLR-2) ligand. This resulted in the construction of 3 CD4-CD8 lipopeptide vaccines. Latently infected HLA Tg rabbits were immunized with a mixture of these 3 ASYMP lipopeptide vaccines, delivered as eye drops in sterile phosphate-buffered saline (PBS). The ASYMP therapeutic vaccination (i) induced HSV-specific CD8+ T cells that prevent HSV-1 reactivation ex vivo from latently infected explanted trigeminal ganglia (TG), (ii) significantly reduced HSV-1 shedding detected in tears, (iii) boosted the number and function of HSV-1 gD epitope-specific CD8+ T cells in draining lymph nodes (DLN), conjunctiva, and TG, and (iv) was associated with fewer exhausted HSV-1 gD-specific PD-1+ TIM-3+ CD8+ T cells. The results underscore the potential of an ASYMP CD8+ T-cell epitope-based therapeutic vaccine strategy against recurrent ocular herpes. IMPORTANCE Seventy percent to 90% of adults harbor herpes simplex virus 1 (HSV-1), which establishes lifelong latency in sensory neurons of the trigeminal ganglia. This latent state sporadically switches to spontaneous reactivation, resulting in viral shedding in tears. Most

  19. Rab3 interacting molecule 3 mutations associated with autism alter regulation of voltage-dependent Ca²⁺ channels.

    PubMed

    Takada, Yoshinori; Hirano, Mitsuru; Kiyonaka, Shigeki; Ueda, Yoshifumi; Yamaguchi, Kazuma; Nakahara, Keiko; Mori, Masayuki X; Mori, Yasuo

    2015-09-01

    Autism is a neurodevelopmental psychiatric disorder characterized by impaired reciprocal social interaction, disrupted communication, and restricted and stereotyped patterns of interests. Autism is known to have a strong genetic component. Although mutations in several genes account for only a small proportion of individuals with autism, they provide insight into potential biological mechanisms that underlie autism, such as dysfunction in Ca(2+) signaling, synaptic dysfunction, and abnormal brain connectivity. In autism patients, two mutations have been reported in the Rab3 interacting molecule 3 (RIM3) gene. We have previously demonstrated that RIM3 physically and functionally interacts with voltage-dependent Ca(2+) channels (VDCCs) expressed in neurons via the β subunits, and increases neurotransmitter release. Here, by introducing corresponding autism-associated mutations that replace glutamic acid residue 176 with alanine (E176A) and methionine residue 259 with valine (M259V) into the C2B domain of mouse RIM3, we demonstrate that both mutations partly cancel the suppressive RIM3 effect on voltage-dependent inactivation of Ba(2+) currents through P/Q-type CaV2.1 recombinantly expressed in HEK293 cells. In recombinant N-type CaV2.2 VDCCs, the attenuation of the suppressive RIM3 effect on voltage-dependent inactivation is conserved for M259V but not E176A. Slowing of activation speed of P/Q-type CaV2.1 currents by RIM3 is abolished in E176A, while the physical interaction between RIM3 and β subunits is significantly attenuated in M259V. Moreover, increases by RIM3 in depolarization-induced Ca(2+) influx and acetylcholine release are significantly attenuated by E176A in rat pheochromocytoma PC12 cells. Thus, our data raise the interesting possibility that autism phenotypes are elicited by synaptic dysfunction via altered regulation of presynaptic VDCC function and neurotransmitter release. PMID:26142343

  20. Vitamin C Attenuates Hemorrhagic Shock-induced Dendritic Cell-specific Intercellular Adhesion Molecule 3-grabbing Nonintegrin Expression in Tubular Epithelial Cells and Renal Injury in Rats

    PubMed Central

    Ma, Li; Fei, Jian; Chen, Ying; Zhao, Bing; Yang, Zhi-Tao; Wang, Lu; Sheng, Hui-Qiu; Chen, Er-Zhen; Mao, En-Qiang

    2016-01-01

    Background: The expression of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) in renal tubular epithelial cells has been thought to be highly correlated with the occurrence of several kidney diseases, but whether it takes place in renal tissues during hemorrhagic shock (HS) is unknown. The present study aimed to investigate this phenomenon and the inhibitory effect of Vitamin C (VitC). Methods: A Sprague–Dawley rat HS model was established in vivo in this study. The expression level and location of DC-SIGN were observed in kidneys. Also, the degree of histological damage, the concentrations of tumor necrosis factor-α and interleukin-6 in the renal tissues, and the serum concentration of blood urea nitrogen and creatinine at different times (2–24 h) after HS (six rats in each group), with or without VitC treatment before resuscitation, were evaluated. Results: HS induced DC-SIGN expression in rat tubular epithelial cells. The proinflammatory cytokine concentration, histological damage scores, and functional injury of kidneys had increased. All these phenomena induced by HS were relieved when the rats were treated with VitC before resuscitation. Conclusions: The results of the present study illustrated that HS could induce tubular epithelial cells expressing DC-SIGN, and the levels of proinflammatory cytokines in the kidney tissues improved correspondingly. The results also indicated that VitC could suppress the DC-SIGN expression in the tubular epithelial cells induced by HS and alleviate the inflammation and functional injury in the kidney. PMID:27411463

  1. Immune checkpoint inhibitors enhance cytotoxicity of cytokine-induced killer cells against human myeloid leukaemic blasts.

    PubMed

    Poh, Su Li; Linn, Yeh Ching

    2016-05-01

    We studied whether blockade of inhibitory receptors on cytokine-induced killer (CIK) cells by immune checkpoint inhibitors could increase its anti-tumour potency against haematological malignancies. CIK cultures were generated from seven normal donors and nine patients with acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL) or multiple myeloma (MM). The inhibitory receptors B and T lymphocyte attenuator, CD200 receptor, lymphocyte activation gene-3 (LAG-3) and T cell immunoglobulin and mucin-domain-containing-3 (TIM-3) were present at variable percentages in most CIK cultures, while cytotoxic T lymphocyte-associated protein 4 (CTLA-4), programmed death-1 (PD-1) and killer cell immunoglobulin-like receptors (KIR2DL1/2/3) were expressed at low level in most cultures. Without blockade, myeloid leukaemia cells were susceptible to autologous and allogeneic CIK-mediated cytotoxicity. Blockade of KIR, LAG-3, PD-1 and TIM-3 but not CTLA-4 resulted in remarkable increase in killing against these targets, even in those with poor baseline cytotoxicity. ALL and MM targets were resistant to CIK-mediated cytotoxicity, and blockade of receptors did not increase cytotoxicity to a meaningful extent. Combination of inhibitors against two receptors did not further increase cytotoxicity. Interestingly, potentiation of CIK killing by blocking antibodies was not predicted by expression of receptors on CIK and their respective ligands on the targets. Compared to un-activated T and NK cells, blockade potentiated the cytotoxicity of CIK cells to a greater degree and at a lower E:T ratio, but without significant increase in cytotoxicity against normal white cell. Our findings provide the basis for clinical trial combining autologous CIK cells with checkpoint inhibitors for patients with AML. PMID:26961084

  2. MicroRNA-155 modulates the pathogen binding ability of dendritic cells (DCs) by down-regulation of DC-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN).

    PubMed

    Martinez-Nunez, Rocio T; Louafi, Fethi; Friedmann, Peter S; Sanchez-Elsner, Tilman

    2009-06-12

    MicroRNA-155 (miR-155) has been involved in the response to inflammation in macrophages and lymphocytes. Here we show how miR-155 participates in the maturation of human dendritic cells (DC) and modulates pathogen binding by down-regulating DC-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN), after directly targeting the transcription factor PU.1. During the maturation of DCs, miR-155 increases up to 130-fold, whereas PU.1 protein levels decrease accordingly. We establish that human PU.1 is a direct target for miR-155 and localize the target sequence for miR-155 in the 3'-untranslated region of PU.1. Also, overexpression of miR-155 in the THP1 monocytic cell line decreases PU.1 protein levels and DC-SIGN at both the mRNA and protein levels. We prove a link between the down-regulation of PU.1 and reduced transcriptional activity of the DC-SIGN promoter, which is likely to be the basis for its reduced mRNA expression, after miR-155 overexpression. Finally, we show that, by reducing DC-SIGN in the cellular membrane, miR-155 is involved in regulating pathogen binding as dendritic cells exhibited the lower binding capacity for fungi and HIV protein gp-120 when the levels of miR-155 were higher. Thus, our results suggest a mechanism by which miR-155 regulates proteins involved in the cellular immune response against pathogens that could have clinical implications in the way pathogens enter the human organism. PMID:19386588

  3. Tumor-induced senescent T cells promote the secretion of pro-inflammatory cytokines and angiogenic factors by human monocytes/macrophages through a mechanism that involves Tim-3 and CD40L

    PubMed Central

    Ramello, M C; Tosello Boari, J; Canale, F P; Mena, H A; Negrotto, S; Gastman, B; Gruppi, A; Acosta Rodríguez, E V; Montes, C L

    2014-01-01

    Solid tumors are infiltrated by immune cells where macrophages and senescent T cells are highly represented. Within the tumor microenvironment, a cross-talk between the infiltrating cells may occur conditioning the characteristic of the in situ immune response. Our previous work showed that tumors induce senescence of T cells, which are powerful suppressors of lympho-proliferation. In this study, we report that Tumor-Induced Senescent (TIS)-T cells may also modulate monocyte activation. To gain insight into this interaction, CD4+ or CD8+TIS-T or control-T cells were co-incubated with autologous monocytes under inflammatory conditions. After co-culture with CD4+ or CD8+TIS-T cells, CD14+ monocytes/macrophages (Mo/Ma) exhibit a higher expression of CD16+ cells and a reduced expression of CD206. These Mo/Ma produce nitric oxide and reactive oxygen species; however, TIS-T cells do not modify phagocyte capacity of Mo/Ma. TIS-T modulated-Mo/Ma show a higher production of pro-inflammatory cytokines (TNF, IL-1β and IL-6) and angiogenic factors (MMP-9, VEGF-A and IL-8) and a lower IL-10 and IP-10 secretion than monocytes co-cultured with controls. The mediator(s) present in the supernatant of TIS-T cell/monocyte-macrophage co-cultures promote(s) tubulogenesis and tumor-cell survival. Monocyte-modulation induced by TIS-T cells requires cell-to-cell contact. Although CD4+ shows different behavior from CD8+TIS-T cells, blocking mAbs against T-cell immunoglobulin and mucin protein 3 and CD40 ligand reduce pro-inflammatory cytokines and angiogenic factors production, indicating that these molecules are involved in monocyte/macrophage modulation by TIS-T cells. Our results revealed a novel role for TIS-T cells in human monocyte/macrophage modulation, which may have deleterious consequences for tumor progression. This modulation should be considered to best tailor the immunotherapy against cancer. PMID:25375372

  4. Mode of action uncovered for the specific reduction of methane emissions from ruminants by the small molecule 3-nitrooxypropanol.

    PubMed

    Duin, Evert C; Wagner, Tristan; Shima, Seigo; Prakash, Divya; Cronin, Bryan; Yáñez-Ruiz, David R; Duval, Stephane; Rümbeli, Robert; Stemmler, René T; Thauer, Rudolf Kurt; Kindermann, Maik

    2016-05-31

    Ruminants, such as cows, sheep, and goats, predominantly ferment in their rumen plant material to acetate, propionate, butyrate, CO2, and methane. Whereas the short fatty acids are absorbed and metabolized by the animals, the greenhouse gas methane escapes via eructation and breathing of the animals into the atmosphere. Along with the methane, up to 12% of the gross energy content of the feedstock is lost. Therefore, our recent report has raised interest in 3-nitrooxypropanol (3-NOP), which when added to the feed of ruminants in milligram amounts persistently reduces enteric methane emissions from livestock without apparent negative side effects [Hristov AN, et al. (2015) Proc Natl Acad Sci USA 112(34):10663-10668]. We now show with the aid of in silico, in vitro, and in vivo experiments that 3-NOP specifically targets methyl-coenzyme M reductase (MCR). The nickel enzyme, which is only active when its Ni ion is in the +1 oxidation state, catalyzes the methane-forming step in the rumen fermentation. Molecular docking suggested that 3-NOP preferably binds into the active site of MCR in a pose that places its reducible nitrate group in electron transfer distance to Ni(I). With purified MCR, we found that 3-NOP indeed inactivates MCR at micromolar concentrations by oxidation of its active site Ni(I). Concomitantly, the nitrate ester is reduced to nitrite, which also inactivates MCR at micromolar concentrations by oxidation of Ni(I). Using pure cultures, 3-NOP is demonstrated to inhibit growth of methanogenic archaea at concentrations that do not affect the growth of nonmethanogenic bacteria in the rumen. PMID:27140643

  5. Single Molecule 3D Orientation in Time and Space: A 6D Dynamic Study on Fluorescently Labeled Lipid Membranes.

    PubMed

    Börner, Richard; Ehrlich, Nicky; Hohlbein, Johannes; Hübner, Christian G

    2016-05-01

    Interactions between single molecules profoundly depend on their mutual three-dimensional orientation. Recently, we demonstrated a technique that allows for orientation determination of single dipole emitters using a polarization-resolved distribution of fluorescence into several detection channels. As the method is based on the detection of single photons, it additionally allows for performing fluorescence correlation spectroscopy (FCS) as well as dynamical anisotropy measurements thereby providing access to fast orientational dynamics down to the nanosecond time scale. The 3D orientation is particularly interesting in non-isotropic environments such as lipid membranes, which are of great importance in biology. We used giant unilamellar vesicles (GUVs) labeled with fluorescent dyes down to a single molecule concentration as a model system for both, assessing the robustness of the orientation determination at different timescales and quantifying the associated errors. The vesicles provide a well-defined spherical surface, such that the use of fluorescent lipid dyes (DiO) allows to establish a a wide range of dipole orientations experimentally. To complement our experimental data, we performed Monte Carlo simulations of the rotational dynamics of dipoles incorporated into lipid membranes. Our study offers a comprehensive view on the dye orientation behavior in a lipid membrane with high spatiotemporal resolution representing a six-dimensional fluorescence detection approach. PMID:26972111

  6. Emerging role of CD300 receptors in regulating myeloid cell efferocytosis

    PubMed Central

    Voss, Oliver H; Tian, Linjie; Murakami, Yousuke; Coligan, John E; Krzewski, Konrad

    2015-01-01

    Engulfment of apoptotic cells is predominantly executed by phagocytes via the recognition of “eat me” signals like phosphatidylserine (PS). Various PS-specific receptors exist on phagocytes, including Tyro3, Axl, and MerTK receptor tyrosine kinases (TAMs), T-cell immunoglobulin and mucin domain containing 1 and 4 (TIM1/4), and the newly identified CD300 family. The aim of the present auto-commentary is to highlight recent findings regarding the Cd300lf and Cd300lb receptors and their emerging roles in the development of autoimmune disease. PMID:27308512

  7. Emerging role of CD300 receptors in regulating myeloid cell efferocytosis.

    PubMed

    Voss, Oliver H; Tian, Linjie; Murakami, Yousuke; Coligan, John E; Krzewski, Konrad

    2015-01-01

    Engulfment of apoptotic cells is predominantly executed by phagocytes via the recognition of "eat me" signals like phosphatidylserine (PS). Various PS-specific receptors exist on phagocytes, including Tyro3, Axl, and MerTK receptor tyrosine kinases (TAMs), T-cell immunoglobulin and mucin domain containing 1 and 4 (TIM1/4), and the newly identified CD300 family. The aim of the present auto-commentary is to highlight recent findings regarding the Cd300lf and Cd300lb receptors and their emerging roles in the development of autoimmune disease. PMID:27308512

  8. Moesin Interacts with the Cytoplasmic Region of Intercellular Adhesion Molecule-3 and Is Redistributed to the Uropod of T Lymphocytes during Cell Polarization

    PubMed Central

    Serrador, Juan M.; Alonso-Lebrero, José L.; Pozo, Miguel A. del; Furthmayr, Heinz; Schwartz-Albiez, Reinhard; Calvo, Javier; Lozano, Francisco; Sánchez-Madrid, Francisco

    1997-01-01

    During activation, T lymphocytes become motile cells, switching from a spherical to a polarized shape. Chemokines and other chemotactic cytokines induce lymphocyte polarization with the formation of a uropod in the rear pole, where the adhesion receptors intercellular adhesion molecule-1 (ICAM-1), ICAM-3, and CD44 redistribute. We have investigated membrane–cytoskeleton interactions that play a key role in the redistribution of adhesion receptors to the uropod. Immunofluorescence analysis showed that the ERM proteins radixin and moesin localized to the uropod of human T lymphoblasts treated with the chemokine RANTES (regulated on activation, normal T cell expressed, and secreted), a polarization-inducing agent; radixin colocalized with arrays of myosin II at the neck of the uropods, whereas moesin decorated the most distal part of the uropod and colocalized with ICAM-1, ICAM-3, and CD44 molecules. Two other cytoskeletal proteins, β-actin and α-tubulin, clustered at the cell leading edge and uropod, respectively, of polarized lymphocytes. Biochemical analysis showed that moesin coimmunoprecipitates with ICAM-3 in T lymphoblasts stimulated with either RANTES or the polarization- inducing anti–ICAM-3 HP2/19 mAb, as well as in the constitutively polarized T cell line HSB-2. In addition, moesin is associated with CD44, but not with ICAM-1, in polarized T lymphocytes. A correlation between the degree of moesin–ICAM-3 interaction and cell polarization was found as determined by immunofluorescence and immunoprecipitation analysis done in parallel. The moesin–ICAM-3 interaction was specifically mediated by the cytoplasmic domain of ICAM-3 as revealed by precipitation of moesin with a GST fusion protein containing the ICAM-3 cytoplasmic tail from metabolically labeled Jurkat T cell lysates. The interaction of moesin with ICAM-3 was greatly diminished when RANTES-stimulated T lymphoblasts were pretreated with the myosin-disrupting drug butanedione monoxime, which prevents lymphocyte polarization. Altogether, these data indicate that moesin interacts with ICAM-3 and CD44 adhesion molecules in uropods of polarized T cells; these data also suggest that these interactions participate in the formation of links between membrane receptors and the cytoskeleton, thereby regulating morphological changes during cell locomotion. PMID:9298994

  9. The granulocyte receptor carcinoembryonic antigen-related cell adhesion molecule 3 (CEACAM3) directly associates with Vav to promote phagocytosis of human pathogens.

    PubMed

    Schmitter, Tim; Pils, Stefan; Sakk, Vadim; Frank, Ronald; Fischer, Klaus-Dieter; Hauck, Christof R

    2007-03-15

    The human granulocyte-specific receptor carcinoembryonic antigen-related cell adhesion molecule (CEACAM)3 is critically involved in the opsonin-independent recognition of several bacterial pathogens. CEACAM3-mediated phagocytosis depends on the integrity of an ITAM-like sequence within the cytoplasmic domain of CEACAM3 and is characterized by rapid stimulation of the GTPase Rac. By performing a functional screen with CEACAM3-expressing cells, we found that overexpression of a dominant-negative form of the guanine nucleotide exchange factor Vav, but not the dominant-negative versions SWAP70, Dock2, or ELMO1 interfered with CEACAM3-initiated phagocytosis. Moreover, small interfering RNA-mediated silencing of Vav reduced uptake and abrogated the stimulation of Rac in response to bacterial CEACAM3 engagement. In Vav1/Vav2-deficient cells, CEACAM3-mediated internalization was only observed after re-expression of Vav. Vav colocalized with CEACAM3 upon bacterial infection, coimmunoprecipitated in a complex with CEACAM3, and the Vav Src homology 2 domain directly associated with phosphorylated Tyr(230) of CEACAM3. In primary human granulocytes, TAT-mediated transduction of dominant-negative Vav, but not SWAP70, severely impaired the uptake of CEACAM3-binding bacteria. These data support the view that, different from canonical ITAM signaling, the CEACAM3 ITAM-like sequence short-wires bacterial recognition and Rac stimulation via a direct association with Vav to promote rapid phagocytosis and elimination of CEACAM-binding human pathogens. PMID:17339478

  10. A comparative study of the vibrational spectra of the anticancer drug melphalan and its fundamental molecules 3-phenylpropionic acid and L-phenylalanine

    NASA Astrophysics Data System (ADS)

    Badawi, Hassan M.; Khan, Ibrahim

    2016-04-01

    The structural stability and the vibrational spectra of the anticancer drug melphalan and its parent compounds 3-phenylpropionic acid and L-phenylalanine were investigated by the DFT B3LYP/6-311G** calculations. Melphalan and its fundamental compounds were predicted to exist predominantly in non-planar structures. The vibrational frequencies of the low energy structures of melphalan, 3-phenylpropionic acid, and phenylalanine were computed at the DFT B3LYP level of theory. Complete vibrational assignments of the normal modes of melphalan, 3-phenylpropionic acid, and phenylalanine were provided by combined theoretical and experimental data of the molecules. The experimental infrared spectra of phenylalanine and melphalan show a significantly different pattern of the Cdbnd O stretching mode as compared to those of normal carboxylic acids. A comparison of the 3700-2000 cm-1 infrared spectral region of the three molecules suggests the presence of similar intermolecular H-bonding in their condensed phases. The observed infrared and Raman spectra are consistent with the presence of one predominant melphalan conformation at room temperature.

  11. Carbon monoxide-releasing molecule 3 inhibits myeloperoxidase (MPO) and protects against MPO-induced vascular endothelial cell activation/dysfunction.

    PubMed

    Patterson, Eric K; Fraser, Douglas D; Capretta, Alfredo; Potter, Richard F; Cepinskas, Gediminas

    2014-05-01

    Polymorphonuclear leukocyte (PMN)-derived myeloperoxidase (MPO) contributes to the pathophysiology of numerous systemic inflammatory disorders through: (1) direct peroxidation of targets and (2) production of strong oxidizing compounds, e.g., hypohalous acids, particularly hypochlorous acid, which furthers oxidant damage and contributes to the propagation of inflammation and tissue injury/dysfunction. Carbon monoxide-releasing molecules (CORMs) offer potent anti-inflammatory effects; however, the mechanism(s) of action is not fully understood. This study assessed the potential of MPO activity inhibition by a water-soluble CORM, CORM-3. To this end, we used in vitro assays to study CORM-3-dependent modulation of MPO activity with respect to: (1) the inhibition of MPO's catalytic activity generally and (2) the specific inhibition of MPO's peroxidation and halogenation (i.e., production of hypochlorous acid) reactions. Further, we employed primary human umbilical vein endothelial cells (HUVECs) to investigate MPO-dependent cellular activation and dysfunction by measuring intracellular oxidant stress (DHR-123 oxidation) and HUVEC permeability (flux of Texas red-dextran), respectively. The results indicate that CORM-3 significantly inhibits MPO activity as well as MPO's peroxidation and hypohalous acid cycles specifically (p<0.05 vs uninhibited MPO). In addition, CORM-3 significantly decreases PMN homogenate- or rhMPO-induced intracellular DHR-123 oxidation in HUVECs and rhMPO-induced HUVEC monolayer permeability (p<0.05 vs untreated). In all assays the inactivated CORM-3 was significantly less effective than CORM-3 (p<0.05). Taken together our findings indicate that CORM-3 is a novel MPO inhibitor and mitigates inflammatory damage at least in part through a mechanism involving the inhibition of neutrophilic MPO activity. PMID:24583458

  12. On the potential involvement of CD11d in co-stimulating the production of interferon-γ by natural killer cells upon interaction with neutrophils via intercellular adhesion molecule-3

    PubMed Central

    Costantini, Claudio; Micheletti, Alessandra; Calzetti, Federica; Perbellini, Omar; Tamassia, Nicola; Albanesi, Cristina; Vermi, William; Cassatella, Marco A.

    2011-01-01

    Interaction between neutrophils and other leukocytes plays a variety of important roles in regulating innate and adaptive immune responses. Recently, we have shown that neu-trophils amplify NK cell/6-sulfo LacNAc+ dendritic cells (slanDC)-mediated cytokine production, by potentiating IL-12p70 release by slanDC via CD18/ICAM-1 and directly co-stimulating IFNγ production by NK cells via ICAM-3. Herein, we have identified additional molecules involved in the interactions among neutrophils, NK cells and slanDC. More specifically, we provide evidence that: i) the cross-talk between neutrophils and NK cells is mediated by ICAM-3 and CD11d/CD18, respectively; ii) slanDC potentiate the production of IFNγ by NK cells via CD11a/CD18. Altogether, our studies shed more light on the role that adhesion molecules play within the neutrophil/NK cell/slanDC network. Our data also have potential implications in the pathogenesis of diseases driven by hyperactivated leukocytes, such as Sweet’s syndrome, in which a neutrophil/NK cell co-localization is frequently observed. PMID:21712539

  13. On the potential involvement of CD11d in co-stimulating the production of interferon-γ by natural killer cells upon interaction with neutrophils via intercellular adhesion molecule-3.

    PubMed

    Costantini, Claudio; Micheletti, Alessandra; Calzetti, Federica; Perbellini, Omar; Tamassia, Nicola; Albanesi, Cristina; Vermi, William; Cassatella, Marco A

    2011-10-01

    Interaction between neutrophils and other leukocytes plays a variety of important roles in regulating innate and adaptive immune responses. Recently, we have shown that neu-trophils amplify NK cell/6-sulfo LacNAc(+) dendritic cells (slanDC)-mediated cytokine production, by potentiating IL-12p70 release by slanDC via CD18/ICAM-1 and directly co-stimulating IFNγ production by NK cells via ICAM-3. Herein, we have identified additional molecules involved in the interactions among neutrophils, NK cells and slanDC. More specifically, we provide evidence that: i) the cross-talk between neutrophils and NK cells is mediated by ICAM-3 and CD11d/CD18, respectively; ii) slanDC potentiate the production of IFNγ by NK cells via CD11a/CD18. Altogether, our studies shed more light on the role that adhesion molecules play within the neutrophil/NK cell/slanDC network. Our data also have potential implications in the pathogenesis of diseases driven by hyperactivated leukocytes, such as Sweet's syndrome, in which a neutrophil/NK cell co-localization is frequently observed. PMID:21712539

  14. Carbon monoxide-releasing molecule-3 (CORM-3; Ru(CO)3Cl(glycinate)) as a tool to study the concerted effects of carbon monoxide and nitric oxide on bacterial flavohemoglobin Hmp: applications and pitfalls.

    PubMed

    Tinajero-Trejo, Mariana; Denby, Katie J; Sedelnikova, Svetlana E; Hassoubah, Shahira A; Mann, Brian E; Poole, Robert K

    2014-10-24

    CO and NO are small toxic gaseous molecules that play pivotal roles in biology as gasotransmitters. During bacterial infection, NO, produced by the host via the inducible NO synthase, exerts critical antibacterial effects while CO, generated by heme oxygenases, enhances phagocytosis of macrophages. In Escherichia coli, other bacteria and fungi, the flavohemoglobin Hmp is the most important detoxification mechanism converting NO and O2 to the ion nitrate (NO3(-)). The protoheme of Hmp binds not only O2 and NO, but also CO so that this ligand is expected to be an inhibitor of NO detoxification in vivo and in vitro. CORM-3 (Ru(CO)(3)Cl(glycinate)) is a metal carbonyl compound extensively used and recently shown to have potent antibacterial properties. In this study, attenuation of the NO resistance of E. coli by CORM-3 is demonstrated in vivo. However, polarographic measurements showed that CO gas, but not CORM-3, produced inhibition of the NO detoxification activity of Hmp in vitro. Nevertheless, CO release from CORM-3 in the presence of soluble cellular compounds is demonstrated by formation of carboxy-Hmp. We show that the inability of CORM-3 to inhibit the activity of purified Hmp is due to slow release of CO in protein solutions alone i.e. when sodium dithionite, widely used in previous studies of CO release from CORM-3, is excluded. Finally, we measure intracellular CO released from CORM-3 by following the formation of carboxy-Hmp in respiring cells. CORM-3 is a tool to explore the concerted effects of CO and NO in vivo. PMID:25193663

  15. Carbon Monoxide-releasing Molecule-3 (CORM-3; Ru(CO)3Cl(Glycinate)) as a Tool to Study the Concerted Effects of Carbon Monoxide and Nitric Oxide on Bacterial Flavohemoglobin Hmp

    PubMed Central

    Tinajero-Trejo, Mariana; Denby, Katie J.; Sedelnikova, Svetlana E.; Hassoubah, Shahira A.; Mann, Brian E.; Poole, Robert K.

    2014-01-01

    CO and NO are small toxic gaseous molecules that play pivotal roles in biology as gasotransmitters. During bacterial infection, NO, produced by the host via the inducible NO synthase, exerts critical antibacterial effects while CO, generated by heme oxygenases, enhances phagocytosis of macrophages. In Escherichia coli, other bacteria and fungi, the flavohemoglobin Hmp is the most important detoxification mechanism converting NO and O2 to the ion nitrate (NO3−). The protoheme of Hmp binds not only O2 and NO, but also CO so that this ligand is expected to be an inhibitor of NO detoxification in vivo and in vitro. CORM-3 (Ru(CO)3Cl(glycinate)) is a metal carbonyl compound extensively used and recently shown to have potent antibacterial properties. In this study, attenuation of the NO resistance of E. coli by CORM-3 is demonstrated in vivo. However, polarographic measurements showed that CO gas, but not CORM-3, produced inhibition of the NO detoxification activity of Hmp in vitro. Nevertheless, CO release from CORM-3 in the presence of soluble cellular compounds is demonstrated by formation of carboxy-Hmp. We show that the inability of CORM-3 to inhibit the activity of purified Hmp is due to slow release of CO in protein solutions alone i.e. when sodium dithionite, widely used in previous studies of CO release from CORM-3, is excluded. Finally, we measure intracellular CO released from CORM-3 by following the formation of carboxy-Hmp in respiring cells. CORM-3 is a tool to explore the concerted effects of CO and NO in vivo. PMID:25193663

  16. Differential Expression of Immune Checkpoint Modulators on In Vitro Primed CD4+ and CD8+ T Cells

    PubMed Central

    Sabins, Nina C.; Harman, Benjamin C.; Barone, Linda R.; Shen, Shixue; Santulli-Marotto, Sandra

    2016-01-01

    PD-1, TIM-3, and LAG-3 are molecules shown to have immune modulatory properties, and although initially classified as indicators of T cell hyporesponsiveness, it has become clear that they are also associated with the normal course of T cell activation. Functional studies have focused mainly on CD8+ T cells during chronic inflammation due to interest in co-opting the cellular immune response to eliminate viral or cancerous threats; however, there remains a relative lack of data regarding the expression of these molecules on CD4+ T cells. Here, we report that expression of the immune checkpoint (IC) molecules PD-1, LAG-3, and TIM-3 are differentially expressed on CD4+ and CD8+ T cells in the allogeneic response resulting from a mixed lymphocyte reaction. In these studies, PD-1 expression is higher on CD4+ T cells compared to CD8+ T cells. In contrast, TIM-3 is expressed at higher levels on CD8+ T cells compared to CD4+ T cells with an apparent reciprocity in that PD-1+ CD4+ T cells are frequently TIM-3lo/−, while TIM-3-expressing CD8+ T cells are largely PD-1lo/−. In addition, there is a decrease in the frequency of TIM-3+ CD4+ cells producing IFN-γ and IL-5 compared to TIM-3+ CD8+ cells. Lastly, the memory T cell phenotype within each IC-expressing subset differs between CD4+ and CD8+ T cells. These findings highlight key differences in IC expression patterns between CD4+ and CD8+ T cells and may allow for more effective therapeutic targeting of these molecules in the future. PMID:27379090

  17. Molecular characterization of T-cell immunoglobulin mucin domain-3 and Galectin-9 genes of swamp- and riverine-type water buffaloes.

    PubMed

    Duran, P L H; Padiernos, R B C; Abella, E A; Konnai, S; Mingala, C N

    2015-12-01

    Molecular characterization of T-cell immunoglobulin mucin domain-3 (TIM-3) and Galectin-9 (GAL-9) genes of swamp- and riverine-type water buffaloes was conducted to compare these genes with other species; determine the unique characteristic specific in water buffalo; and provide baseline information for the assessment of disease progression in buffalo species. TIM-3 and GAL-9 genes were amplified, purified, sequenced and characterized. The sequence result of TIM-3 in both types of water buffaloes contained 843 nucleotides encoding to 280 amino acids while GAL-9 of swamp-type and riverine-type water buffaloes contained 1023 and 972 nucleotides encoding to 340 and 323 amino acids, respectively. Meanwhile, the nucleotide and amino sequence of TIM-3 in water buffalo were 83-98% and 94-97% identical with other artiodactyl species, respectively. On the other hand, GAL-9 nucleotide and amino acid sequence in water buffalo were 85-98% and 76-96% identical with other artiodactyl species. The tyrosine-kinase phosphorylation motif and potential glycosylation sites were conserved within the tribe Bovinae. It is imperative to have further studies in the assessment of the role of these genes in disease progression in water buffalo during chronic infection. The study is the first report that describes the genetic characteristic of TIM-3 and GAL-9 genes in water buffalo. PMID:26441033

  18. T cell immunoglobulin domain and mucin domain-3 as an emerging target for immunotherapy in cancer management

    PubMed Central

    Yoneda, Akihiro; Jinushi, Masahisa

    2013-01-01

    Cancer-induced immunosuppression significantly impacts tumors, rendering them the ability to acquire aggressive and treatment-resistant phenotypes. The recent clinical success of drugs targeting the immunosuppressive machinery of tumors highlights the importance of identifying novel drugs that effectively augment antitumor immunity and elicit clinical remission in advanced tumors. T cell immunoglobulin domain and mucin domain-3 (TIM-3) is a critical immunoregulatory molecule that links pattern recognition-mediated innate sensing with antigen-specific immune responses. Recent evidence has elucidated the potential utility of drugs targeting TIM-3 in inducing antitumor responses, particularly in synergy with conventional anticancer regimens. Herein, we provide a comprehensive overview, as well as future perspectives, regarding the role of TIM-3 as an emerging target that may improve clinical responses for cancer patients.

  19. Expression of coinhibitory receptors on T cells in the microenvironment of usual vulvar intraepithelial neoplasia is related to proinflammatory effector T cells and an increased recurrence-free survival.

    PubMed

    van Esch, Edith M G; van Poelgeest, Mariette I E; Kouwenberg, Simone; Osse, E Michelle; Trimbos, J Baptist M Z; Fleuren, Gert Jan; Jordanova, Ekaterina S; van der Burg, Sjoerd H

    2015-02-15

    Human papillomavirus-induced usual-type vulvar intraepithelial neoplasia (uVIN) are infiltrated by immune cells but apparently not cleared. A potential explanation for this is an impaired T cell effector function by an immunesuppressive milieu, coinfiltrating regulatory T cells or the expression of coinhibitory molecules. Here, the role of these potential inhibitory mechanisms was evaluated by a detailed immunohistochemical analysis of T cell infiltration in the context of FoxP3, Tbet, indoleamine 2,3-dioxygenase, programmed cell death 1, T cell immunoglobulin mucin 3 (TIM3), natural killer cell lectin-like receptor A (NKG2A) and galectins-1, -3 and -9. Paraffin-embedded tissues of primary uVIN lesions (n=43), recurrent uVIN lesions (n=20), vulvar carcinoma (n=21) and healthy vulvar tissue (n=26) were studied. We show that the vulva constitutes an area intensely surveyed by CD8+, CD4+, Tbet+ and regulatory T cell populations, parts of which express the examined coinhibitory molecules. In uVIN especially, the number of regulatory T cells and TIM3+ T cells increased. The expression of the coinhibitory markers TIM3 and NKG2A probably reflected a higher degree of T cell activation as a dense infiltration with stromal CD8+TIM3+ T cells and CD3+NKG2A+ T cells was related to the absence of recurrences and/or a prolonged recurrence-free survival. A dense coinfiltrate with regulatory T cells was negatively associated with the time to recurrence, most dominantly when the stromal CD8+TIM3+ infiltration was limited. This notion was sustained in vulvar carcinoma's where the numbers of regulatory T cells progressively increased to outnumber coinfiltrating CD8+TIM3+ T cells and CD3+NKG2A+ T cells. PMID:25220367

  20. Replacement of Oxygen by Sulfur in Small Organic Molecules. 3. Theoretical Studies on the Tautomeric Equilibria of the 2OH and 4OH-Substituted Oxazole and Thiazole and the 3OH and 4OH-Substituted Isoxazole and Isothiazole in the Isolated State and in Solution

    PubMed Central

    Nagy, Peter I.

    2016-01-01

    This follow-up paper completes the author’s investigations to explore the in-solution structural preferences and relative free energies of all OH-substituted oxazole, thiazole, isoxazole, and isothiazole systems. The polarizable continuum dielectric solvent method calculations in the integral-equation formalism (IEF-PCM) were performed at the DFT/B97D/aug-cc-pv(q+(d))z level for the stable neutral tautomers with geometries optimized in dichloromethane and aqueous solution. With the exception of the predictions for the predominant tautomers of the 3OH isoxazole and isothiazole, the results of the IEF-PCM calculations for identifying the most stable tautomer of the given species in the two selected solvents agreed with those from experimental investigations. The calculations predict that the hydroxy proton, with the exception for the 4OH isoxazole and 4OH isothiazole, moves preferentially to the ring nitrogen or to a ring carbon atom in parallel with the development of a C=O group. The remaining, low-fraction OH tautomers will not be observable in the equilibrium compositions. Relative solvation free energies obtained by the free energy perturbation method implemented in Monte Carlo simulations are in moderate accord with the IEF-PCM results, but consideration of the ΔGsolv/MC values in calculating ΔGstot maintains the tautomeric preferences. It was revealed from the Monte Carlo solution structure analyses that the S atom is not a hydrogen-bond acceptor in any OH-substituted thiazole or isothiazole, and the OH-substituted isoxazole and oxazole ring oxygens may act as a weak hydrogen-bond acceptor at most. The molecules form 1.0−3.4 solute−water hydrogen bonds in generally unexplored numbers at some specific solute sites. Nonetheless, hydrogen-bond formation is favorable with the NH, C=O and OH groups. PMID:27409605

  1. Replacement of Oxygen by Sulfur in Small Organic Molecules. 3. Theoretical Studies on the Tautomeric Equilibria of the 2OH and 4OH-Substituted Oxazole and Thiazole and the 3OH and 4OH-Substituted Isoxazole and Isothiazole in the Isolated State and in Solution.

    PubMed

    Nagy, Peter I

    2016-01-01

    This follow-up paper completes the author's investigations to explore the in-solution structural preferences and relative free energies of all OH-substituted oxazole, thiazole, isoxazole, and isothiazole systems. The polarizable continuum dielectric solvent method calculations in the integral-equation formalism (IEF-PCM) were performed at the DFT/B97D/aug-cc-pv(q+(d))z level for the stable neutral tautomers with geometries optimized in dichloromethane and aqueous solution. With the exception of the predictions for the predominant tautomers of the 3OH isoxazole and isothiazole, the results of the IEF-PCM calculations for identifying the most stable tautomer of the given species in the two selected solvents agreed with those from experimental investigations. The calculations predict that the hydroxy proton, with the exception for the 4OH isoxazole and 4OH isothiazole, moves preferentially to the ring nitrogen or to a ring carbon atom in parallel with the development of a C=O group. The remaining, low-fraction OH tautomers will not be observable in the equilibrium compositions. Relative solvation free energies obtained by the free energy perturbation method implemented in Monte Carlo simulations are in moderate accord with the IEF-PCM results, but consideration of the ΔGsolv/MC values in calculating ΔG(s)tot maintains the tautomeric preferences. It was revealed from the Monte Carlo solution structure analyses that the S atom is not a hydrogen-bond acceptor in any OH-substituted thiazole or isothiazole, and the OH-substituted isoxazole and oxazole ring oxygens may act as a weak hydrogen-bond acceptor at most. The molecules form 1.0-3.4 solute-water hydrogen bonds in generally unexplored numbers at some specific solute sites. Nonetheless, hydrogen-bond formation is favorable with the NH, C=O and OH groups. PMID:27409605

  2. On-demand erythrocyte disposal and iron recycling requires transient macrophages in the liver.

    PubMed

    Theurl, Igor; Hilgendorf, Ingo; Nairz, Manfred; Tymoszuk, Piotr; Haschka, David; Asshoff, Malte; He, Shun; Gerhardt, Louisa M S; Holderried, Tobias A W; Seifert, Markus; Sopper, Sieghart; Fenn, Ashley M; Anzai, Atsushi; Rattik, Sara; McAlpine, Cameron; Theurl, Milan; Wieghofer, Peter; Iwamoto, Yoshiko; Weber, Georg F; Harder, Nina K; Chousterman, Benjamin G; Arvedson, Tara L; McKee, Mary; Wang, Fudi; Lutz, Oliver M D; Rezoagli, Emanuele; Babitt, Jodie L; Berra, Lorenzo; Prinz, Marco; Nahrendorf, Matthias; Weiss, Guenter; Weissleder, Ralph; Lin, Herbert Y; Swirski, Filip K

    2016-08-01

    Iron is an essential component of the erythrocyte protein hemoglobin and is crucial to oxygen transport in vertebrates. In the steady state, erythrocyte production is in equilibrium with erythrocyte removal. In various pathophysiological conditions, however, erythrocyte life span is compromised severely, which threatens the organism with anemia and iron toxicity. Here we identify an on-demand mechanism that clears erythrocytes and recycles iron. We show that monocytes that express high levels of lymphocyte antigen 6 complex, locus C1 (LY6C1, also known as Ly-6C) ingest stressed and senescent erythrocytes, accumulate in the liver via coordinated chemotactic cues, and differentiate into ferroportin 1 (FPN1, encoded by SLC40A1)-expressing macrophages that can deliver iron to hepatocytes. Monocyte-derived FPN1(+)Tim-4(neg) macrophages are transient, reside alongside embryonically derived T cell immunoglobulin and mucin domain containing 4 (Timd4, also known as Tim-4)(high) Kupffer cells (KCs), and depend on the growth factor Csf1 and the transcription factor Nrf2 (encoded by Nfe2l2). The spleen, likewise, recruits iron-loaded Ly-6C(high) monocytes, but these do not differentiate into iron-recycling macrophages, owing to the suppressive action of Csf2. The accumulation of a transient macrophage population in the liver also occurs in mouse models of hemolytic anemia, anemia of inflammation, and sickle cell disease. Inhibition of monocyte recruitment to the liver during stressed erythrocyte delivery leads to kidney and liver damage. These observations identify the liver as the primary organ that supports rapid erythrocyte removal and iron recycling, and uncover a mechanism by which the body adapts to fluctuations in erythrocyte integrity. PMID:27428900

  3. Semaphorin4A Is Cytotoxic to Oligodendrocytes and Is Elevated in Microglia and Multiple Sclerosis.

    PubMed

    Leitner, Dominique F; Todorich, Bozho; Zhang, Xuesheng; Connor, James R

    2015-01-01

    We have previously established that T cell immunoglobulin and mucin domain containing 2 (Tim2) is an H-ferritin receptor on oligodendrocytes (OLs). Tim2 also binds Semaphorin4A (Sema4A). Sema4A is expressed by lymphocytes, and its role in immune activation is known; however, its relationship to diseases that are known to have myelin damage has not been studied. In this study, we demonstrate that Sema4A is cytotoxic to OLs in culture: an effect accompanied by process collapse, membrane blebbing, and phosphatidylserine inversion. We further demonstrate that Sema4A preferentially binds to primary OLs but not astrocytes: an observation consistent with the lack of expression of Tim2 on astrocytes. We found that Sema4A protein levels are increased within multiple sclerosis plaques compared with normal-appearing white matter and that Sema4A induces lactate dehydrogenase release in a human OL cell line. The chief cellular source of Sema4A within the multiple sclerosis plaques appears to be infiltrating lymphocytes and microglia. Macrophages are known to express Sema4A, so we interrogated microglia as a potential source of Sema4A in the brain. We found that rat primary microglia express Sema4A which increased after lipopolysaccharide activation. Because activated microglia accumulate iron, we determined whether iron status influenced Sema4A and found that iron chelation decreased Sema4A and iron loading increased Sema4A in activated microglia. Overall, our data implicate Sema4A in the destruction of OLs and reveal that its expression is sensitive to iron levels. PMID:26024919

  4. Semaphorin4A Is Cytotoxic to Oligodendrocytes and Is Elevated in Microglia and Multiple Sclerosis

    PubMed Central

    Leitner, Dominique F.; Todorich, Bozho; Zhang, Xuesheng

    2015-01-01

    We have previously established that T cell immunoglobulin and mucin domain containing 2 (Tim2) is an H-ferritin receptor on oligodendrocytes (OLs). Tim2 also binds Semaphorin4A (Sema4A). Sema4A is expressed by lymphocytes, and its role in immune activation is known; however, its relationship to diseases that are known to have myelin damage has not been studied. In this study, we demonstrate that Sema4A is cytotoxic to OLs in culture: an effect accompanied by process collapse, membrane blebbing, and phosphatidylserine inversion. We further demonstrate that Sema4A preferentially binds to primary OLs but not astrocytes: an observation consistent with the lack of expression of Tim2 on astrocytes. We found that Sema4A protein levels are increased within multiple sclerosis plaques compared with normal-appearing white matter and that Sema4A induces lactate dehydrogenase release in a human OL cell line. The chief cellular source of Sema4A within the multiple sclerosis plaques appears to be infiltrating lymphocytes and microglia. Macrophages are known to express Sema4A, so we interrogated microglia as a potential source of Sema4A in the brain. We found that rat primary microglia express Sema4A which increased after lipopolysaccharide activation. Because activated microglia accumulate iron, we determined whether iron status influenced Sema4A and found that iron chelation decreased Sema4A and iron loading increased Sema4A in activated microglia. Overall, our data implicate Sema4A in the destruction of OLs and reveal that its expression is sensitive to iron levels. PMID:26024919

  5. T Cell Immunoglobulin Mucin-3 Crystal Structure Reveals a Galectin-9-Independent Ligand-Binding Surface

    SciTech Connect

    Cao,E.; Zang, X.; Ramagopal, U.; Mukhopadhaya, A.; Fedorov, A.; Fedorov, E.; Zencheck, W.; Lary, J.; Cole, J.; et al.

    2007-01-01

    The T cell immunoglobulin mucin (Tim) family of receptors regulates effector CD4+ T cell functions and is implicated in autoimmune and allergic diseases. Tim-3 induces immunological tolerance, and engagement of the Tim-3 immunoglobulin variable (IgV) domain by galectin-9 is important for appropriate termination of T helper 1-immune responses. The 2 {angstrom} crystal structure of the Tim-3 IgV domain demonstrated that four cysteines, which are invariant within the Tim family, form two noncanonical disulfide bonds, resulting in a surface not present in other immunoglobulin superfamily members. Biochemical and biophysical studies demonstrated that this unique structural feature mediates a previously unidentified galectin-9-independent binding process and suggested that this structural feature is conserved within the entire Tim family. The current work provided a graphic example of the relationship between sequence, structure, and function and suggested that the interplay between multiple Tim-3-binding activities contributes to the regulated assembly of signaling complexes required for effective Th1-mediated immunity.

  6. Adaptive resistance to therapeutic PD-1 blockade is associated with upregulation of alternative immune checkpoints

    PubMed Central

    Koyama, Shohei; Akbay, Esra A.; Li, Yvonne Y.; Herter-Sprie, Grit S.; Buczkowski, Kevin A.; Richards, William G.; Gandhi, Leena; Redig, Amanda J.; Rodig, Scott J.; Asahina, Hajime; Jones, Robert E.; Kulkarni, Meghana M.; Kuraguchi, Mari; Palakurthi, Sangeetha; Fecci, Peter E.; Johnson, Bruce E.; Janne, Pasi A.; Engelman, Jeffrey A.; Gangadharan, Sidharta P.; Costa, Daniel B.; Freeman, Gordon J.; Bueno, Raphael; Hodi, F. Stephen; Dranoff, Glenn; Wong, Kwok-Kin; Hammerman, Peter S.

    2016-01-01

    Despite compelling antitumour activity of antibodies targeting the programmed death 1 (PD-1): programmed death ligand 1 (PD-L1) immune checkpoint in lung cancer, resistance to these therapies has increasingly been observed. In this study, to elucidate mechanisms of adaptive resistance, we analyse the tumour immune microenvironment in the context of anti-PD-1 therapy in two fully immunocompetent mouse models of lung adenocarcinoma. In tumours progressing following response to anti-PD-1 therapy, we observe upregulation of alternative immune checkpoints, notably T-cell immunoglobulin mucin-3 (TIM-3), in PD-1 antibody bound T cells and demonstrate a survival advantage with addition of a TIM-3 blocking antibody following failure of PD-1 blockade. Two patients who developed adaptive resistance to anti-PD-1 treatment also show a similar TIM-3 upregulation in blocking antibody-bound T cells at treatment failure. These data suggest that upregulation of TIM-3 and other immune checkpoints may be targetable biomarkers associated with adaptive resistance to PD-1 blockade. PMID:26883990

  7. Chronicle of Higher Education. Volume 51, Number 25, February 25, 2005

    ERIC Educational Resources Information Center

    Chronicle of Higher Education, 2005

    2005-01-01

    "Chronicle of Higher Education" presents an abundant source of news and information for college and university faculty members and administrators. This February 25, 2005 issue of "Chronicle of Higher Education" includes the following articles: (1) "Sins of Admission" (Sumner, James); (2) "Admissions Today: 6 Experts Speak Out" (Foley, Tim); (3)…

  8. Roles of the programmed cell death 1, T cell immunoglobulin mucin-3, and cluster of differentiation 288 pathways in the low reactivity of invariant natural killer T cells after chronic hepatitis B virus infection.

    PubMed

    Yang, Zhixin; Lei, Yu; Chen, Chunbo; Ren, Hong; Shi, Tongdong

    2015-10-01

    One of the main responses of invariant natural killer T (iNKT) cells to antigen stimulation is the rapid production of interleukin (IL)-4 and interferon (IFN)-γ cytokines. There is a decline in the function of iNKT cells in chronic hepatitis B (CHB) patients. In this study, we explored the impact of programmed cell death 1 (PD-1), T cell immunoglobulin mucin-3 (Tim-3), and cluster of differentiation 28 (CD28) expression on iNKT cell functions in CHB patients. Flow cytometry was used to test iNKT frequencies and levels of PD-1, Tim-3, CD28, IL-4, and IFN-γ secreted by iNKT cells. An enzyme-linked immunosorbent assay (ELISA) was used to measure IL-4 and IFN-γ secretion upon α-galactosylceramide (α-GalCer) activation ex vivo. We found that the levels of expression of PD-1 and Tim-3 from iNKT cells in CHB patients were significantly higher than in healthy donors (p < 0.05), but there was lower expression of CD28 (p < 0.05) and an impaired capability to produce IL-4 and IFN-γ (p < 0.05). In vitro α-GalCer stimulation upregulated the expression of PD-1(+) iNKT cells (p < 0.05), Tim-3(+) iNKT cells (p < 0.05), and CD28(+) iNKT cells (p < 0.05). In response to combination therapies consisting of α-GalCer and anti-PDL1 monoclonal antibody (mAb) and/or anti-Tim-3 mAbs and/or anti-CD80/anti-CD28 mAbs, IL-4(+) and IFN-γ(+) iNKT cells demonstrated different degrees of growth (p < 0.05). The functional decline of iNKT cells was closely related to the decrease in CD28 expression and the increases of Tim-3 and PD-1. In addition, clinical antiviral treatment with lamivudine could partially restore the immune function of iNKT cells in CHB patients. PMID:26215444

  9. Development of Timd2 as a reporter gene for MRI

    PubMed Central

    Patrick, P. Stephen; Rodrigues, Tiago B.; Kettunen, Mikko I.; Lyons, Scott K.; Neves, André A.

    2015-01-01

    Purpose To assess the potential of an MRI gene reporter based on the ferritin receptor Timd2 (T‐cell immunoglobulin and mucin domain containing protein 2), using T1‐ and T2‐weighted imaging. Methods Pellets of cells that had been modified to express the Timd2 transgene, and incubated with either iron‐loaded or manganese‐loaded ferritin, were imaged using T1‐ and T2‐weighted MRI. Mice were also implanted subcutaneously with Timd2‐expressing cells and the resulting xenograft tissue imaged following intravenous injection of ferritin using T2‐weighted imaging. Results Timd2‐expressing cells, but not control cells, showed a large increase in both R2 and R1 in vitro following incubation with iron‐loaded and manganese‐loaded ferritin, respectively. Expression of Timd2 had no effect on cell viability or proliferation; however, manganese‐loaded ferritin, but not iron‐loaded ferritin, was toxic to Timd2‐expressing cells. Timd2‐expressing xenografts in vivo showed much smaller changes in R2 following injection of iron‐loaded ferritin than the same cells incubated in vitro with iron‐loaded ferritin. Conclusion Timd2 has demonstrated potential as an MRI reporter gene, producing large increases in R2 and R1 with ferritin and manganese‐loaded ferritin respectively in vitro, although more modest changes in R2 in vivo. Manganese‐loaded apoferritin was not used in vivo due to the toxicity observed in vitro. Magn Reson Med, 2015. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Magn Reson Med 75:1697–1707, 2016. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society

  10. Plasma biomarkers of acute GVHD and nonrelapse mortality: predictive value of measurements before GVHD onset and treatment.

    PubMed

    McDonald, George B; Tabellini, Laura; Storer, Barry E; Lawler, Richard L; Martin, Paul J; Hansen, John A

    2015-07-01

    We identified plasma biomarkers that presaged outcomes in patients with gastrointestinal graft-versus-host disease (GVHD) by measuring 23 biomarkers in samples collected before initiation of treatment. Six analytes with the greatest accuracy in predicting grade 3-4 GVHD in the first cohort (74 patients) were then tested in a second cohort (76 patients). The same 6 analytes were also tested in samples collected at day 14 ± 3 from 167 patients free of GVHD at the time. Logistic regression and calculation of an area under a receiver-operating characteristic (ROC) curve for each analyte were used to determine associations with outcome. Best models in the GVHD onset and landmark analyses were determined by forward selection. In samples from the second cohort, collected a median of 4 days before start of treatment, levels of TIM3, IL6, and sTNFR1 had utility in predicting development of peak grade 3-4 GVHD (area under ROC curve, 0.88). Plasma ST2 and sTNFR1 predicted nonrelapse mortality within 1 year after transplantation (area under ROC curve, 0.90). In the landmark analysis, plasma TIM3 predicted subsequent grade 3-4 GVHD (area under ROC curve, 0.76). We conclude that plasma levels of TIM3, sTNFR1, ST2, and IL6 are informative in predicting more severe GVHD and nonrelapse mortality. PMID:25987657

  11. Blockage of Galectin-receptor Interactions by α-lactose Exacerbates Plasmodium berghei-induced Pulmonary Immunopathology.

    PubMed

    Liu, Jinfeng; Huang, Shiguang; Su, Xin-Zhuan; Song, Jianping; Lu, Fangli

    2016-01-01

    Malaria-associated acute lung injury (ALI) is a frequent complication of severe malaria that is often caused by "excessive" immune responses. To better understand the mechanism of ALI in malaria infection, here we investigated the roles of galectin (Gal)-1, 3, 8, 9 and the receptors of Gal-9 (Tim-3, CD44, CD137, and PDI) in malaria-induced ALI. We injected alpha (α)-lactose into mice-infected with Plasmodium berghei ANKA (PbANKA) to block galectins and found significantly elevated total proteins in bronchoalveolar lavage fluid, higher parasitemia and tissue parasite burden, and increased numbers of CD68(+) alveolar macrophages as well as apoptotic cells in the lungs after blockage. Additionally, mRNA levels of Gal-9, Tim-3, CD44, CD137, and PDI were significantly increased in the lungs at day 5 after infection, and the levels of CD137, IFN-α, IFN-β, IFN-γ, IL-4, and IL-10 in the lungs were also increased after α-lactose treatment. Similarly, the levels of Gal-9, Tim-3, IFN-α, IFN-β, IFN-γ, and IL-10 were all significantly increased in murine peritoneal macrophages co-cultured with PbANKA-infected red blood cells in vitro; but only IFN-α and IFN-β were significantly increased after α-lactose treatment. Our data indicate that Gal-9 interaction with its multiple receptors play an important role in murine malaria-associated ALI. PMID:27554340

  12. Blockage of Galectin-receptor Interactions by α-lactose Exacerbates Plasmodium berghei-induced Pulmonary Immunopathology

    PubMed Central

    Liu, Jinfeng; Huang, Shiguang; Su, Xin-zhuan; Song, Jianping; Lu, Fangli

    2016-01-01

    Malaria-associated acute lung injury (ALI) is a frequent complication of severe malaria that is often caused by “excessive” immune responses. To better understand the mechanism of ALI in malaria infection, here we investigated the roles of galectin (Gal)-1, 3, 8, 9 and the receptors of Gal-9 (Tim-3, CD44, CD137, and PDI) in malaria-induced ALI. We injected alpha (α)-lactose into mice-infected with Plasmodium berghei ANKA (PbANKA) to block galectins and found significantly elevated total proteins in bronchoalveolar lavage fluid, higher parasitemia and tissue parasite burden, and increased numbers of CD68+ alveolar macrophages as well as apoptotic cells in the lungs after blockage. Additionally, mRNA levels of Gal-9, Tim-3, CD44, CD137, and PDI were significantly increased in the lungs at day 5 after infection, and the levels of CD137, IFN-α, IFN-β, IFN-γ, IL-4, and IL-10 in the lungs were also increased after α-lactose treatment. Similarly, the levels of Gal-9, Tim-3, IFN-α, IFN-β, IFN-γ, and IL-10 were all significantly increased in murine peritoneal macrophages co-cultured with PbANKA-infected red blood cells in vitro; but only IFN-α and IFN-β were significantly increased after α-lactose treatment. Our data indicate that Gal-9 interaction with its multiple receptors play an important role in murine malaria-associated ALI. PMID:27554340

  13. Type I Interferon Elevates Co-Regulatory Receptor Expression on CMV- and EBV-Specific CD8 T Cells in Chronic Hepatitis C

    PubMed Central

    Owusu Sekyere, Solomon; Suneetha, Pothakamuri Venkata; Hardtke, Svenja; Falk, Christine Susanne; Hengst, Julia; Manns, Michael Peter; Cornberg, Markus; Wedemeyer, Heiner; Schlaphoff, Verena

    2015-01-01

    Hepatitis C virus (HCV) readily sets up persistence in a large fraction of infected hosts. Mounting epidemiological and immunological evidence suggest that HCV’s persistence could influence immune responses toward unrelated pathogens and vaccines. Nonetheless, the fundamental contribution of the inflammatory milieu during persistent HCV infection in impacting immune cells specific for common pathogens such as CMV and EBV has not been fully studied. As the co-regulatory receptors PD-1, Tim-3, and 2B4 have all been shown to be vital in regulating CD8+ T cell function, we assessed their expression on CMV/EBV-specific CD8+ T cells from patients with chronic hepatitis C (CHC) and healthy controls ex vivo and upon stimulation with virus-specific peptides in vitro. Total and CMV/EBV-specific CD8+ T cells expressing PD-1, Tim-3, and 2B4 were highly enriched in patients with CHC compared to healthy individuals ex vivo. In vitro peptide stimulation further potentiated the differential co-regulatory receptor expression of PD-1, Tim-3, and 2B4, which then culminated in an enhanced functionality of CMV/EBV-specific CD8+ T cells in CHC patients. Comprehensively analyzing plasma cytokines between the two cohorts, we observed that not only was IFNα-2a dominant among 21 other inflammatory mediators elevated in CHC patients but it also correlated with PD-1 and Tim-3 expressions ex vivo. Importantly, IFNα-2a further caused upregulation of these markers upon in vitro peptide stimulation. Finally, we could prospectively study patients receiving novel IFN-free antiviral therapy. Here, we observed that treatment-induced clearance of HCV resulted in a partial reversion of the phenotype of CMV/EBV-specific CD8+ T cells in patients with CHC. These data reveal an alteration of the plasma concentrations of IFNα-2a together with other inflammatory mediators during CHC, which appeared to pervasively influence co-regulatory receptor expression on CMV/EBV-specific CD8+ T cells. PMID:26113847

  14. TIM-family proteins inhibit HIV-1 release

    PubMed Central

    Li, Minghua; Ablan, Sherimay D.; Miao, Chunhui; Zheng, Yi-Min; Fuller, Matthew S.; Rennert, Paul D.; Maury, Wendy; Johnson, Marc C.; Freed, Eric O.; Liu, Shan-Lu

    2014-01-01

    Accumulating evidence indicates that T-cell immunoglobulin (Ig) and mucin domain (TIM) proteins play critical roles in viral infections. Herein, we report that the TIM-family proteins strongly inhibit HIV-1 release, resulting in diminished viral production and replication. Expression of TIM-1 causes HIV-1 Gag and mature viral particles to accumulate on the plasma membrane. Mutation of the phosphatidylserine (PS) binding sites of TIM-1 abolishes its ability to block HIV-1 release. TIM-1, but to a much lesser extent PS-binding deficient mutants, induces PS flipping onto the cell surface; TIM-1 is also found to be incorporated into HIV-1 virions. Importantly, TIM-1 inhibits HIV-1 replication in CD4-positive Jurkat cells, despite its capability of up-regulating CD4 and promoting HIV-1 entry. In addition to TIM-1, TIM-3 and TIM-4 also block the release of HIV-1, as well as that of murine leukemia virus (MLV) and Ebola virus (EBOV); knockdown of TIM-3 in differentiated monocyte-derived macrophages (MDMs) enhances HIV-1 production. The inhibitory effects of TIM-family proteins on virus release are extended to other PS receptors, such as Axl and RAGE. Overall, our study uncovers a novel ability of TIM-family proteins to block the release of HIV-1 and other viruses by interaction with virion- and cell-associated PS. Our work provides new insights into a virus-cell interaction that is mediated by TIMs and PS receptors. PMID:25136083

  15. Short Communication: Low Expression of Activation and Inhibitory Molecules on NK Cells and CD4(+) T Cells Is Associated with Viral Control.

    PubMed

    Taborda, Natalia A; Hernández, Juan C; Lajoie, Julie; Juno, Jennifer A; Kimani, Joshua; Rugeles, María T; Fowke, Keith R

    2015-06-01

    Chronic HIV-1 infection induces severe immune alterations, including hyperactivation, exhaustion, and apoptosis. In fact, viral control has been associated with low frequencies of these processes. Here, we evaluated the expression of activation and inhibitory molecules on natural killer (NK) and CD4(+) T cells and plasma levels of proinflammatory cytokines in individuals exhibiting viral control: a cohort of HIV-1-exposed-seronegative individuals (HESN) and a cohort of HIV controllers. There was lower expression of CD69, LAG-3, PD-1, and TIM-3 in both cohorts when compared to a low-risk population or HIV progressors. In addition, HIV controllers exhibited lower plasma levels of proinflamatory molecules TNF-α and IP-10. These findings suggest that individuals exhibiting viral control have lower basal expression of markers associated with cellular activation and particularly immune exhaustion. PMID:25738606

  16. Immunological biomarkers predict HIV-1 viral rebound after treatment interruption

    PubMed Central

    Hurst, Jacob; Hoffmann, Matthias; Pace, Matthew; Williams, James P.; Thornhill, John; Hamlyn, Elizabeth; Meyerowitz, Jodi; Willberg, Chris; Koelsch, Kersten K.; Robinson, Nicola; Brown, Helen; Fisher, Martin; Kinloch, Sabine; Cooper, David A.; Schechter, Mauro; Tambussi, Giuseppe; Fidler, Sarah; Babiker, Abdel; Weber, Jonathan; Kelleher, Anthony D.; Phillips, Rodney E.; Frater, John

    2015-01-01

    Treatment of HIV-1 infection with antiretroviral therapy (ART) in the weeks following transmission may induce a state of ‘post-treatment control' (PTC) in some patients, in whom viraemia remains undetectable when ART is stopped. Explaining PTC could help our understanding of the processes that maintain viral persistence. Here we show that immunological biomarkers can predict time to viral rebound after stopping ART by analysing data from a randomized study of primary HIV-1 infection incorporating a treatment interruption (TI) after 48 weeks of ART (the SPARTAC trial). T-cell exhaustion markers PD-1, Tim-3 and Lag-3 measured prior to ART strongly predict time to the return of viraemia. These data indicate that T-cell exhaustion markers may identify those latently infected cells with a higher proclivity to viral transcription. Our results may open new avenues for understanding the mechanisms underlying PTC, and eventually HIV-1 eradication. PMID:26449164

  17. Immunological biomarkers predict HIV-1 viral rebound after treatment interruption.

    PubMed

    Hurst, Jacob; Hoffmann, Matthias; Pace, Matthew; Williams, James P; Thornhill, John; Hamlyn, Elizabeth; Meyerowitz, Jodi; Willberg, Chris; Koelsch, Kersten K; Robinson, Nicola; Brown, Helen; Fisher, Martin; Kinloch, Sabine; Cooper, David A; Schechter, Mauro; Tambussi, Giuseppe; Fidler, Sarah; Babiker, Abdel; Weber, Jonathan; Kelleher, Anthony D; Phillips, Rodney E; Frater, John

    2015-01-01

    Treatment of HIV-1 infection with antiretroviral therapy (ART) in the weeks following transmission may induce a state of 'post-treatment control' (PTC) in some patients, in whom viraemia remains undetectable when ART is stopped. Explaining PTC could help our understanding of the processes that maintain viral persistence. Here we show that immunological biomarkers can predict time to viral rebound after stopping ART by analysing data from a randomized study of primary HIV-1 infection incorporating a treatment interruption (TI) after 48 weeks of ART (the SPARTAC trial). T-cell exhaustion markers PD-1, Tim-3 and Lag-3 measured prior to ART strongly predict time to the return of viraemia. These data indicate that T-cell exhaustion markers may identify those latently infected cells with a higher proclivity to viral transcription. Our results may open new avenues for understanding the mechanisms underlying PTC, and eventually HIV-1 eradication. PMID:26449164

  18. A Phase I/II Trial of Belinostat in Combination with Cisplatin, Doxorubicin and Cyclophosphamide in Thymic Epithelial Tumors: A Clinical And Translational Study

    PubMed Central

    Thomas, Anish; Rajan, Arun; Szabo, Eva; Tomita, Yusuke; Carter, Corey A.; Scepura, Barbara; Lopez-Chavez, Ariel; Lee, Min-Jung; Redon, Christophe E.; Frosch, Ari; Peer, Cody J.; Chen, Yuanbin; Piekarz, Richard; Steinberg, Seth M.; Trepel, Jane B.; Figg, William D.; Schrump, David S.; Giaccone, Giuseppe

    2014-01-01

    Purpose This phase I/II study sought to determine the safety and maximum-tolerated dose (MTD) of a novel schedule of belinostat, a histone deacetylase inhibitor administered prior to and in combination with cisplatin (P), doxorubicin (A) and cyclophosphamide (C) in thymic epithelial tumors (TET). Anti-tumor activity, pharmacokinetics, and biomarkers of response were also assessed. Patients and methods Patients with advanced, unresectable TET received increasing doses of belinostat as a continuous intravenous infusion over 48-hours with chemotherapy in 3-week cycles. In phase II, belinostat at the MTD was used. Results 26 patients were enrolled (thymoma: 12; thymic carcinoma: 14). Dose-limiting toxicities at 2000 mg/m2 belinostat were grade 3 nausea and diarrhea and grade 4 neutropenia and thrombocytopenia, respectively, in two patients. 24 patients were treated at the MTD of 1000 mg/m2 with chemotherapy (P 50 mg/m2 on day 2; A 25 mg/m2 on days 2, 3; C 500 mg/m2 on day 3). Objective response rates in thymoma and thymic carcinoma were 64% [95% confidence interval: 30.8%–89.1%] and 21% (4.7%–50.8%) respectively. Modulation of pharmacodynamic markers of HDAC-inhibition and declines in regulatory T cell (Tregs) and exhausted CD8+ T cell populations were observed. Decline in Tregs was associated with response (p=0.0041) and progression-free survival (p=0.021). Declines in TIM-3+ CD8+T cells were larger in responders than non-responders (p=0.049). Conclusion This study identified the MTD of belinostat in combination with PAC and indicates that the combination is active and feasible in TETs. Immunomodulatory effects on regulatory T cells and TIM3+ CD8+ T cells warrant further study. PMID:25189481

  19. Leukemia Stem Cell-Released Microvesicles Promote the Survival and Migration of Myeloid Leukemia Cells and These Effects Can Be Inhibited by MicroRNA34a Overexpression

    PubMed Central

    Wang, Yue; Cheng, Qian; Liu, Jing; Dong, Min

    2016-01-01

    Leukemia stem cells (LSCs) play the major role in relapse of acute myeloid leukemia (AML). Recent evidence indicates that microvesicles (MVs) released from cancer stem cells can promote tumor growth and invasion. In this study, we investigated whether LSCs-released MVs (LMVs) can regulate the malignance of AML cells and whether overexpression of tumor suppressive microRNA (miR), miR34a, is able to interrupt this process. LSCs were transfected with miRNA control (miRCtrl) or miR34a mimic for producing LMVs, respectively, defined as LMVsmiRCtrl and LMVsmiR34a. The effect of miR34a transfection on LSC proliferation and the effects of LMVsmiRCtrl or LMVsmiR34a on the proliferation, migration, and apoptosis of AML cells (after LSC depletion) were determined. The levels of miR34a targets, caspase-3 and T cell immunoglobulin mucin-3 (Tim-3), were analyzed. Results showed that (1) LMVsmiRCtrl promoted proliferation and migration and inhibited apoptosis of AML cells, which were associated with miR34a deficit; (2) transfection of miR34a mimic inhibited LSC proliferation and increased miR34a level in LMVsmiR34a; (3) LMVsmiR34a produced opposite effects as compared with LMVsmiRCtrl, which were associated with the changes of caspase-3 and Tim-3 levels. In summary, LMVs support AML cell malignance and modulating miR34a could offer a new approach for the management of AML. PMID:27127521

  20. Antigen spreading-induced CD8+T cells confer protection against the lethal challenge of wild-type malignant mesothelioma by eliminating myeloid-derived suppressor cells

    PubMed Central

    Lee, Boon Kiat; Tang, Jiansong; Wu, Xilin; Cheung, Ka-Wai; Lok Lo, Nathan Tin; Man, Kwan; Liu, Li; Chen, Zhiwei

    2015-01-01

    A key focus in cancer immunotherapy is to investigate the mechanism of efficacious vaccine responses. Using HIV-1 GAG-p24 in a model PD1-based DNA vaccine, we recently reported that vaccine-elicited CD8+ T cells conferred complete prevention and therapeutic cure of AB1-GAG malignant mesothelioma in immunocompetent BALB/c mice. Here, we further investigated the efficacy and correlation of protection on the model vaccine-mediated antigen spreading against wild-type AB1 (WT-AB1) mesothelioma. We found that this vaccine was able to protect mice completely from three consecutive lethal challenges of AB1-GAG mesothelioma. Through antigen spreading these animals also developed tumor-specific cytotoxic CD8+ T cells, but neither CD4+ T cells nor antibodies, rejecting WT-AB1 mesothelioma. A majority of these protected mice (90%) were also completely protected against the lethal WT-AB1 challenge. Adoptive cell transfer experiments further demonstrated that antigen spreading-induced CD8+ T cells conferred efficacious therapeutic effects against established WT-AB1 mesothelioma and prevented the increase of exhausted PD-1+ and Tim-3+ CD8+ T cells. A significant inverse correlation was found between the frequency of functional PD1−Tim3− CD8+ T cells and that of MDSCs or tumor mass in vivo. Mechanistically, we found that WT-AB1 mesothelioma induced predominantly polymorphonuclear (PMN) MDSCs in vivo. In co-cultures with efficacious CD8+ T cells, a significant number of PMN-MDSCs underwent apoptosis in a dose-dependent way. Our findings indicate that efficacious CD8+ T cells capable of eliminating both tumor cells and MDSCs are likely necessary for fighting wild-type malignant mesothelioma. PMID:26431275

  1. Costimulation-Adhesion Blockade is Superior to Cyclosporine A and Prednisone Immunosuppressive Therapy for Preventing Rejection of Differentiated Human Embryonic Stem Cells Following Transplantation

    PubMed Central

    Huber, Bruno C.; Ransohoff, Julia D.; Ransohoff, Katherine J.; Riegler, Johannes; Ebert, Antje; Kodo, Kazuki; Gong, Yongquan; Sanchez-Freire, Veronica; Dey, Devaveena; Kooreman, Nigel G.; Diecke, Sebastian; Zhang, Wendy Y.; Odegaard, Justin; Hu, Shijun; Gold, Joseph D.; Robbins, Robert C.; Wu, Joseph C.

    2014-01-01

    Rationale Human embryonic stem cell (hESC) derivatives are attractive candidates for therapeutic use. The engraftment and survival of hESC derivatives as xenografts or allografts require effective immunosuppression to prevent immune cell infiltration and graft destruction. Objective To test the hypothesis that a short-course, dual-agent regimen of two costimulation-adhesion blockade agents can induce better engraftment of hESC derivatives compared to current immunosuppressive agents. Methods and Results We transduced hESCs with a double fusion reporter gene construct expressing firefly luciferase (Fluc) and enhanced green fluorescent protein (eGFP), and differentiated these cells to endothelial cells (hESC-ECs). Reporter gene expression enabled longitudinal assessment of cell engraftment by bioluminescence imaging (BLI). Costimulation-adhesion therapy resulted in superior hESC-EC and mouse EC engraftment compared to cyclosporine therapy in a hindlimb model. Costimulation-adhesion therapy also promoted robust hESC-EC and hESC-derived cardiomyocyte (hESC-CM) survival in an ischemic myocardial injury model. Improved hESC-EC engraftment had a cardioprotective effect after myocardial injury, as assessed by magnetic resonance imaging (MRI). Mechanistically, costimulation-adhesion therapy is associated with systemic and intra-graft upregulation of T cell immunoglobulin and mucin domain 3 (TIM3) and a reduced pro-inflammatory cytokine profile. Conclusions Costimulation-adhesion therapy is a superior alternative to current clinical immunosuppressive strategies for preventing the post-transplant rejection of hESC derivatives. By extending the window for cellular engraftment, costimulation-adhesion therapy enhances functional preservation following ischemic injury. This regimen may function through a TIM3-dependent mechanism. PMID:24038578

  2. Exhaustion of Activated CD8 T Cells Predicts Disease Progression in Primary HIV-1 Infection

    PubMed Central

    Hickling, Stephen; Hurst, Jacob; Meyerowitz, Jodi; Willberg, Christian B.; Robinson, Nicola; Brown, Helen; Kinloch, Sabine; Babiker, Abdel; Nwokolo, Nneka; Fox, Julie; Fidler, Sarah; Phillips, Rodney; Frater, John

    2016-01-01

    The rate at which HIV-1 infected individuals progress to AIDS is highly variable and impacted by T cell immunity. CD8 T cell inhibitory molecules are up-regulated in HIV-1 infection and associate with immune dysfunction. We evaluated participants (n = 122) recruited to the SPARTAC randomised clinical trial to determine whether CD8 T cell exhaustion markers PD-1, Lag-3 and Tim-3 were associated with immune activation and disease progression. Expression of PD-1, Tim-3, Lag-3 and CD38 on CD8 T cells from the closest pre-therapy time-point to seroconversion was measured by flow cytometry, and correlated with surrogate markers of HIV-1 disease (HIV-1 plasma viral load (pVL) and CD4 T cell count) and the trial endpoint (time to CD4 count <350 cells/μl or initiation of antiretroviral therapy). To explore the functional significance of these markers, co-expression of Eomes, T-bet and CD39 was assessed. Expression of PD-1 on CD8 and CD38 CD8 T cells correlated with pVL and CD4 count at baseline, and predicted time to the trial endpoint. Lag-3 expression was associated with pVL but not CD4 count. For all exhaustion markers, expression of CD38 on CD8 T cells increased the strength of associations. In Cox models, progression to the trial endpoint was most marked for PD-1/CD38 co-expressing cells, with evidence for a stronger effect within 12 weeks from confirmed diagnosis of PHI. The effect of PD-1 and Lag-3 expression on CD8 T cells retained statistical significance in Cox proportional hazards models including antiretroviral therapy and CD4 count, but not pVL as co-variants. Expression of ‘exhaustion’ or ‘immune checkpoint’ markers in early HIV-1 infection is associated with clinical progression and is impacted by immune activation and the duration of infection. New markers to identify exhausted T cells and novel interventions to reverse exhaustion may inform the development of novel immunotherapeutic approaches. PMID:27415828

  3. Role of Type I Interferon Signaling in Human Metapneumovirus Pathogenesis and Control of Viral Replication

    PubMed Central

    Hastings, Andrew K.; Erickson, John J.; Schuster, Jennifer E.; Boyd, Kelli L.; Tollefson, Sharon J.; Johnson, Monika; Gilchuk, Pavlo; Joyce, Sebastian

    2015-01-01

    ABSTRACT Type I IFN signaling, which is initiated through activation of the alpha interferon receptor (IFNAR), regulates the expression of proteins that are crucial contributors to immune responses. Paramyxoviruses, including human metapneumovirus (HMPV), have evolved mechanisms to inhibit IFNAR signaling, but the specific contribution of IFNAR signaling to the control of HMPV replication, pathogenesis, and adaptive immunity is unknown. We used IFNAR-deficient (IFNAR−/−) mice to assess the effect of IFNAR signaling on HMPV replication and the CD8+ T cell response. HMPV-infected IFNAR−/− mice had a higher peak of early viral replication but cleared the virus with kinetics similar to those of wild-type (WT) mice. However, IFNAR−/− mice infected with HMPV displayed less airway dysfunction and lung inflammation. CD8+ T cells of IFNAR−/− mice after HMPV infection expressed levels of the inhibitory receptor programmed death 1 (PD-1) similar to those of WT mice. However, despite lower expression of inhibitory programmed death ligand 1 (PD-L1), HMPV-specific CD8+ T cells of IFNAR−/− mice were more functionally impaired than those of WT mice and upregulated the inhibitory receptor Tim-3. Analysis of the antigen-presenting cell subsets in the lungs revealed that the expansion of PD-L1low dendritic cells (DCs), but not PD-L1high alveolar macrophages, was dependent on IFNAR signaling. Collectively, our results indicate a role for IFNAR signaling in the early control of HMPV replication, disease progression, and the development of an optimal adaptive immune response. Moreover, our findings suggest an IFNAR-independent mechanism of lung CD8+ T cell impairment. IMPORTANCE Human metapneumovirus (HMPV) is a leading cause of acute respiratory illness. CD8+ T cells are critical for clearing viral infection, yet recent evidence shows that HMPV and other respiratory viruses induce CD8+ T cell impairment via PD-1–PD-L1 signaling. We sought to understand the role of

  4. Exhaustion of Activated CD8 T Cells Predicts Disease Progression in Primary HIV-1 Infection.

    PubMed

    Hoffmann, Matthias; Pantazis, Nikos; Martin, Genevieve E; Hickling, Stephen; Hurst, Jacob; Meyerowitz, Jodi; Willberg, Christian B; Robinson, Nicola; Brown, Helen; Fisher, Martin; Kinloch, Sabine; Babiker, Abdel; Weber, Jonathan; Nwokolo, Nneka; Fox, Julie; Fidler, Sarah; Phillips, Rodney; Frater, John

    2016-07-01

    The rate at which HIV-1 infected individuals progress to AIDS is highly variable and impacted by T cell immunity. CD8 T cell inhibitory molecules are up-regulated in HIV-1 infection and associate with immune dysfunction. We evaluated participants (n = 122) recruited to the SPARTAC randomised clinical trial to determine whether CD8 T cell exhaustion markers PD-1, Lag-3 and Tim-3 were associated with immune activation and disease progression. Expression of PD-1, Tim-3, Lag-3 and CD38 on CD8 T cells from the closest pre-therapy time-point to seroconversion was measured by flow cytometry, and correlated with surrogate markers of HIV-1 disease (HIV-1 plasma viral load (pVL) and CD4 T cell count) and the trial endpoint (time to CD4 count <350 cells/μl or initiation of antiretroviral therapy). To explore the functional significance of these markers, co-expression of Eomes, T-bet and CD39 was assessed. Expression of PD-1 on CD8 and CD38 CD8 T cells correlated with pVL and CD4 count at baseline, and predicted time to the trial endpoint. Lag-3 expression was associated with pVL but not CD4 count. For all exhaustion markers, expression of CD38 on CD8 T cells increased the strength of associations. In Cox models, progression to the trial endpoint was most marked for PD-1/CD38 co-expressing cells, with evidence for a stronger effect within 12 weeks from confirmed diagnosis of PHI. The effect of PD-1 and Lag-3 expression on CD8 T cells retained statistical significance in Cox proportional hazards models including antiretroviral therapy and CD4 count, but not pVL as co-variants. Expression of 'exhaustion' or 'immune checkpoint' markers in early HIV-1 infection is associated with clinical progression and is impacted by immune activation and the duration of infection. New markers to identify exhausted T cells and novel interventions to reverse exhaustion may inform the development of novel immunotherapeutic approaches. PMID:27415828

  5. CEACAM1 mediates B cell aggregation in central nervous system autoimmunity

    PubMed Central

    Rovituso, Damiano M.; Scheffler, Laura; Wunsch, Marie; Dörck, Sebastian; Ulzheimer, Jochen; Bayas, Antonios; Steinman, Lawrence; Ergün, Süleyman; Kuerten, Stefanie

    2016-01-01

    B cell aggregates in the central nervous system (CNS) have been associated with rapid disease progression in patients with multiple sclerosis (MS). Here we demonstrate a key role of carcinoembryogenic antigen-related cell adhesion molecule1 (CEACAM1) in B cell aggregate formation in MS patients and a B cell-dependent mouse model of MS. CEACAM1 expression was increased on peripheral blood B cells and CEACAM1+ B cells were present in brain infiltrates of MS patients. Administration of the anti-CEACAM1 antibody T84.1 was efficient in blocking aggregation of B cells derived from MS patients. Along these lines, application of the monoclonal anti-CEACAM1 antibody mCC1 was able to inhibit CNS B cell aggregate formation and significantly attenuated established MS-like disease in mice in the absence of any adverse effects. CEACAM1 was co-expressed with the regulator molecule T cell immunoglobulin and mucin domain −3 (TIM-3) on B cells, a novel molecule that has recently been described to induce anergy in T cells. Interestingly, elevated coexpression on B cells coincided with an autoreactive T helper cell phenotype in MS patients. Overall, these data identify CEACAM1 as a clinically highly interesting target in MS pathogenesis and open new therapeutic avenues for the treatment of the disease. PMID:27435215

  6. Molecular Drivers of the Non-T-cell-Inflamed Tumor Microenvironment in Urothelial Bladder Cancer.

    PubMed

    Sweis, Randy F; Spranger, Stefani; Bao, Riyue; Paner, Gladell P; Stadler, Walter M; Steinberg, Gary; Gajewski, Thomas F

    2016-07-01

    Muscle-invasive urothelial bladder cancer is a common malignancy with poor outcomes for which immune checkpoint blockade is now showing promise. Despite clinical activity of PD-1/PD-L1-targeted therapy in this disease, most patients do not benefit and resistance mechanisms remain unknown. The non-T-cell-inflamed tumor microenvironment correlates with poor prognosis and resistance to immunotherapies. In this study, we determined tumor-oncogenic pathways correlating with T-cell exclusion. We first establish in this report that T-cell-inflamed bladder tumors can be identified by immune gene expression profiling with concordance with CD8(+) T-cell infiltration. Upregulation of genes encoding immune checkpoint proteins PD-L1, IDO, FOXP3, TIM3, and LAG3 was associated with T-cell-inflamed tumors, suggesting potential for sensitivity to checkpoint blockade. β-Catenin, PPAR-γ, and FGFR3 pathways were activated in non-T-cell-inflamed tumors. No difference was seen in overall somatic mutational density between groups. The three pathways identified represent targetable potential pathways of tumor-intrinsic immunotherapy resistance. Cancer Immunol Res; 4(7); 563-8. ©2016 AACR. PMID:27197067

  7. Control of Immune Response to Allogeneic Embryonic Stem Cells by CD3 Antibody-Mediated Operational Tolerance Induction.

    PubMed

    Calderon, D; Prot, M; You, S; Marquet, C; Bellamy, V; Bruneval, P; Valette, F; de Almeida, P; Wu, J C; Pucéat, M; Menasché, P; Chatenoud, L

    2016-02-01

    Implantation of embryonic stem cells (ESCs) and their differentiated derivatives into allogeneic hosts triggers an immune response that represents a hurdle to clinical application. We established in autoimmunity and in transplantation that CD3 antibody therapy induces a state of immune tolerance. Promising results have been obtained with CD3 antibodies in the clinic. In this study, we tested whether this strategy can prolong the survival of undifferentiated ESCs and their differentiated derivatives in histoincompatible hosts. Recipients of either mouse ESC-derived embryoid bodies (EBs) or cardiac progenitors received a single short tolerogenic regimen of CD3 antibody. In immunocompetent mice, allogeneic EBs and cardiac progenitors were rejected within 20-25 days. Recipients treated with CD3 antibody showed long-term survival of implanted cardiac progenitors or EBs. In due course, EBs became teratomas, the growth of which was self-limited. Regulatory CD4(+)FoxP3(+) T cells and signaling through the PD1/PDL1 pathway played key roles in the CD3 antibody therapeutic effect. Gene profiling emphasized the importance of TGF-β and the inhibitory T cell coreceptor Tim3 to the observed effect. These results demonstrate that CD3 antibody administered alone promotes prolonged survival of allogeneic ESC derivatives and thus could prove useful for enhancing cell engraftment in the absence of chronic immunosuppression. PMID:26492394

  8. mir-276a strengthens Drosophila circadian rhythms by regulating timeless expression.

    PubMed

    Chen, Xiao; Rosbash, Michael

    2016-05-24

    Circadian rhythms in metazoan eukaryotes are controlled by an endogenous molecular clock. It functions in many locations, including subsets of brain neurons (clock neurons) within the central nervous system. Although the molecular clock relies on transcription/translation feedback loops, posttranscriptional regulation also plays an important role. Here, we show that the abundant Drosophila melanogaster microRNA mir-276a regulates molecular and behavioral rhythms by inhibiting expression of the important clock gene timeless (tim). Misregulation of mir-276a in clock neurons alters tim expression and increases arrhythmicity under standard constant darkness (DD) conditions. mir-276a expression itself appears to be light-regulated because its levels oscillate under 24-h light-dark (LD) cycles but not in DD. mir-276a is regulated by the transcription activator Chorion factor 2 in flies and in tissue-culture cells. Evidence from flies mutated using the clustered, regularly interspaced, short palindromic repeats (CRISPR) tool shows that mir-276a inhibits tim expression: Deleting the mir-276a-binding site in the tim 3' UTR causes elevated levels of TIM and ∼50% arrhythmicity. We suggest that this pathway contributes to the more robust rhythms observed under light/dark LD conditions than under DD conditions. PMID:27162360

  9. Broad Spectrum Activity of a Lectin-Like Bacterial Serine Protease Family on Human Leukocytes

    PubMed Central

    Ayala-Lujan, Jorge Luis; Vijayakumar, Vidhya; Gong, Mei; Smith, Rachel; Santiago, Araceli E.; Ruiz-Perez, Fernando

    2014-01-01

    The serine protease autotransporter from Enterobacteriaceae (SPATE) family, which number more than 25 proteases with apparent diverse functions, have been phylogenetically divided into two distinct classes, designated 1 and 2. We recently demonstrated that Pic and Tsh, two members of the class-2 SPATE family produced by intestinal and extraintestinal pathogenic E. coli, were able to cleave a number of O-glycosylated proteins on neutrophils and lymphocytes resulting in impaired leukocyte functions. Here we show that most members of the class-2 SPATE family have lectin-like properties and exhibit differential protease activity reliant on glycoprotein type and cell lineage. Protease activity was seen in virtually all tested O-glycosylated proteins including CD34, CD55, CD164, TIM1, TIM3, TIM4 and C1-INH. We also show that although SPATE proteins bound and cleaved glycoproteins more efficiently on granulocytes and monocytes, they also targeted glycoproteins on B, T and natural killer lymphocytes. Finally, we found that the characteristic domain-2 of class-2 SPATEs is not required for glycoprotease activity, but single amino acid mutations in Pic domain-1 to those residues naturally occurring in domain-1 of SepA, were sufficient to hamper Pic glycoprotease activity. This study shows that most class-2 SPATEs have redundant activities and suggest that they may function as immunomodulators at several levels of the immune system. PMID:25251283

  10. Combinatorial approach to cancer immunotherapy: strength in numbers.

    PubMed

    Vilgelm, Anna E; Johnson, Douglas B; Richmond, Ann

    2016-08-01

    Immune-checkpoint blockade therapy with antibodies targeting CTLA-4 and PD-1 has revolutionized melanoma treatment by eliciting responses that can be remarkably durable and is now advancing to other malignancies. However, not all patients respond to immune-checkpoint inhibitors. Extensive preclinical evidence suggests that combining immune-checkpoint inhibitors with other anti-cancer treatments can greatly improve the therapeutic benefit. The first clinical success of the combinatorial approach to cancer immunotherapy was demonstrated using a dual-checkpoint blockade with CTLA-4 and PD-1 inhibitors, which resulted in accelerated FDA approval of this therapeutic regimen. In this review, we discuss the combinations of current and emerging immunotherapeutic agents in clinical and preclinical development and summarize the insights into potential mechanisms of synergistic anti-tumor activity gained from animal studies. These promising combinatorial partners for the immune-checkpoint blockade include therapeutics targeting additional inhibitory receptors of T cells, such as TIM-3, LAG-3, TIGIT, and BTLA, and agonists of T cell costimulatory receptors 4-1BB, OX40, and GITR, as well as agents that promote cancer cell recognition by the immune system, such as tumor vaccines, IDO inhibitors, and agonists of the CD40 receptor of APCs. We also review the therapeutic potential of regimens combining the immune-checkpoint blockade with therapeutic interventions that have been shown to enhance immunogenicity of cancer cells, including oncolytic viruses, RT, epigenetic therapy, and senescence-inducing therapy. PMID:27256570

  11. Specific CD8+ T cell response immunotherapy for hepatocellular carcinoma and viral hepatitis

    PubMed Central

    Moreno-Cubero, Elia; Larrubia, Juan-Ramón

    2016-01-01

    Hepatocellular carcinoma (HCC), chronic hepatitis B (CHB) and chronic hepatitis C (CHC) are characterized by exhaustion of the specific CD8+ T cell response. This process involves enhancement of negative co-stimulatory molecules, such as programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte antigen-4 (CTLA-4), 2B4, Tim-3, CD160 and LAG-3, which is linked to intrahepatic overexpression of some of the cognate ligands, such as PD-L1, on antigen presenting cells and thereby favouring a tolerogenic environment. Therapies that disrupt these negative signalling mechanisms represent promising therapeutic tools with the potential to restore reactivity of the specific CD8+ T cell response. In this review we discuss the impressive in vitro and in vivo results that have been recently achieved in HCC, CHB and CHC by blocking these negative receptors with monoclonal antibodies against these immune checkpoint modulators. The article mainly focuses on the role of CTLA-4 and PD-1 blocking monoclonal antibodies, the first ones to have reached clinical practice. The humanized monoclonal antibodies against CTLA-4 (tremelimumab and ipilimumab) and PD-1 (nivolumab and pembrolizumab) have yielded good results in testing of HCC and chronic viral hepatitis patients. Trelimumab, in particular, has shown a significant increase in the time to progression in HCC, while nivolumab has shown a remarkable effect on hepatitis C viral load reduction. The research on the role of ipilimumab, nivolumab and pembrolizumab on HCC is currently underway.

  12. Chronic Activation of Innate Immunity Correlates With Poor Prognosis in Cancer Patients Treated With Oncolytic Adenovirus.

    PubMed

    Taipale, Kristian; Liikanen, Ilkka; Juhila, Juuso; Turkki, Riku; Tähtinen, Siri; Kankainen, Matti; Vassilev, Lotta; Ristimäki, Ari; Koski, Anniina; Kanerva, Anna; Diaconu, Iulia; Cerullo, Vincenzo; Vähä-Koskela, Markus; Oksanen, Minna; Linder, Nina; Joensuu, Timo; Lundin, Johan; Hemminki, Akseli

    2016-02-01

    Despite many clinical trials conducted with oncolytic viruses, the exact tumor-level mechanisms affecting therapeutic efficacy have not been established. Currently there are no biomarkers available that would predict the clinical outcome to any oncolytic virus. To assess the baseline immunological phenotype and find potential prognostic biomarkers, we monitored mRNA expression levels in 31 tumor biopsy or fluid samples from 27 patients treated with oncolytic adenovirus. Additionally, protein expression was studied from 19 biopsies using immunohistochemical staining. We found highly significant changes in several signaling pathways and genes associated with immune responses, such as B-cell receptor signaling (P < 0.001), granulocyte macrophage colony-stimulating factor (GM-CSF) signaling (P < 0.001), and leukocyte extravasation signaling (P < 0.001), in patients surviving a shorter time than their controls. In immunohistochemical analysis, markers CD4 and CD163 were significantly elevated (P = 0.020 and P = 0.016 respectively), in patients with shorter than expected survival. Interestingly, T-cell exhaustion marker TIM-3 was also found to be significantly upregulated (P = 0.006) in patients with poor prognosis. Collectively, these data suggest that activation of several functions of the innate immunity before treatment is associated with inferior survival in patients treated with oncolytic adenovirus. Conversely, lack of chronic innate inflammation at baseline may predict improved treatment outcome, as suggested by good overall prognosis. PMID:26310629

  13. IL2Rβ-dependent signals drive terminal exhaustion and suppress memory development during chronic viral infection.

    PubMed

    Beltra, Jean-Christophe; Bourbonnais, Sara; Bédard, Nathalie; Charpentier, Tania; Boulangé, Moana; Michaud, Eva; Boufaied, Ines; Bruneau, Julie; Shoukry, Naglaa H; Lamarre, Alain; Decaluwe, Hélène

    2016-09-13

    Exhaustion of CD8(+) T cells severely impedes the adaptive immune response to chronic viral infections. Despite major advances in our understanding of the molecular regulation of exhaustion, the cytokines that directly control this process during chronicity remain unknown. We demonstrate a direct impact of IL-2 and IL-15, two common gamma-chain-dependent cytokines, on CD8(+) T-cell exhaustion. Common to both cytokine receptors, the IL-2 receptor β (IL2Rβ) chain is selectively maintained on CD8(+) T cells during chronic lymphocytic choriomeningitis virus and hepatitis C virus infections. Its expression correlates with exhaustion severity and identifies terminally exhausted CD8(+) T cells both in mice and humans. Genetic ablation of the IL2Rβ chain on CD8(+) T cells restrains inhibitory receptor induction, in particular 2B4 and Tim-3; precludes terminal differentiation of highly defective PD-1(hi) effectors; and rescues memory T-cell development and responsiveness to IL-7-dependent signals. Together, we ascribe a previously unexpected role to IL-2 and IL-15 as instigators of CD8(+) T-cell exhaustion during chronic viral infection. PMID:27573835

  14. Follicular Lymphoma: The Role of the Tumor Microenvironment in Prognosis.

    PubMed

    Sugimoto, Takumi; Watanabe, Takashi

    2016-01-01

    The microenvironment of follicular lymphoma (FL) is composed of tumor-infiltrating CD8(+) T cells, follicular regulatory T cells, lymphoma-associated macrophages and mast cells, follicular helper T cells, follicular dendritic cells, and follicular reticular cells, all of which have been reported to have relevance in the prognosis of FL patients. In addition, some of these cells play a role in the histologic transformation of FL. Macrophages contribute to a poor prognosis in FL patients treated in the pre-rituximab era, but are associated with good prognosis in those treated in the rituximab era. T-cell immunoglobulin and mucin domain protein (TIM) 3 are markers of T-cell exhaustion, and T cells co-expressing programed death 1 (PD1) in peripheral blood and lymph nodes secrete interleukin (IL)-12 in the serum. Serum CXCL9, IL-2 receptor, and IL-1 receptor agonist are associated with shorter survival of FL patients. Agents for manipulation of the microenvironment surrounding FL cells include the immunomodulatory drug lenalidomide, immune check-point inhibitors, and cyclophosphamide prior to rituximab. To battle FL and to improve the outcomes of FL patients, understanding the relationship between neoplastic cells and the various microenvironmental cellular components is crucial for developing therapeutics against the microenvironment. PMID:27334853

  15. Orchestrating immune check-point blockade for cancer immunotherapy in combinations.

    PubMed

    Perez-Gracia, Jose Luis; Labiano, Sara; Rodriguez-Ruiz, Maria E; Sanmamed, Miguel F; Melero, Ignacio

    2014-04-01

    Inhibitory receptors on immune system cells respond to membrane-bound and soluble ligands to abort or mitigate the intensity of immune responses by raising thresholds of activation, halting proliferation, favoring apoptosis or inhibiting/deviating effector function differentiation. Such evolutionarily selected inhibitory mechanisms are termed check-points and therefore check-point inhibitors empower any ongoing anti-cancer immune response that might have been too weak or exhausted. Monoclonal antibodies (mAb) interfering with CTLA-4-CD80/86, PD-1 - PD-L1, TIM-3-GAL9 and LAG3-MHC-II belong to this category of check-point inhibitors. The anti-CTLA-4 mAb ipilimumab has been approved for metastatic melanoma. Anti-PD-1 and anti-PD-L1 mAbs have shown extremely encouraging clinical activity. The potential of combination strategies with these agents has recently been highlighted by clinical observations on CTLA-4+PD-1 combined blockade in melanoma patients. PMID:24485523

  16. Molecular signatures of T-cell inhibition in HIV-1 infection

    PubMed Central

    2013-01-01

    Cellular immune responses play a crucial role in the control of viral replication in HIV-infected individuals. However, the virus succeeds in exploiting the immune system to its advantage and therefore, the host ultimately fails to control the virus leading to development of terminal AIDS. The virus adopts numerous evasion mechanisms to hijack the host immune system. We and others recently described the expression of inhibitory molecules on T cells as a contributing factor for suboptimal T-cell responses in HIV infection both in vitro and in vivo. The expression of these molecules that negatively impacts the normal functions of the host immune armory and the underlying signaling pathways associated with their enhanced expression need to be discussed. Targets to restrain the expression of these molecular markers of immune inhibition is likely to contribute to development of therapeutic interventions that augment the functionality of host immune cells leading to improved immune control of HIV infection. In this review, we focus on the functions of inhibitory molecules that are expressed or secreted following HIV infection such as BTLA, CTLA-4, CD160, IDO, KLRG1, LAG-3, LILRB1, PD-1, TRAIL, TIM-3, and regulatory cytokines, and highlight their significance in immune inhibition. We also highlight the ensemble of transcriptional factors such as BATF, BLIMP-1/PRDM1, FoxP3, DTX1 and molecular pathways that facilitate the recruitment and differentiation of suppressor T cells in response to HIV infection. PMID:23514593

  17. An adaptive immune response driven by mature, antigen-experienced T and B cells within the microenvironment of oral squamous cell carcinoma.

    PubMed

    Quan, Hongzhi; Fang, Liangjuan; Pan, Hao; Deng, Zhiyuan; Gao, Shan; Liu, Ousheng; Wang, Yuehong; Hu, Yanjia; Fang, Xiaodan; Yao, Zhigang; Guo, Feng; Lu, Ruohuang; Xia, Kun; Tang, Zhangui

    2016-06-15

    Lymphocyte infiltrates have been observed in the microenvironment of oral cancer; however, little is known about whether the immune response of the lymphocyte infiltrate affects tumor biology. For a deeper understanding of the role of the infiltrating-lymphocytes in oral squamous cell carcinoma (OSCC), we characterized the lymphocyte infiltrate repertoires and defined their features. Immunohistochemistry revealed considerable T and B cell infiltrates and lymphoid follicles with germinal center-like structures within the tumor microenvironment. Flow cytometry demonstrated that populations of antigen-experienced CD4+ and CD8+ cells were present, as well as an enrichment of regulatory T cells; and T cells expressing programmed death-1 (PD-1) and T cell Ig and mucin protein-3 (Tim-3), indicative of exhaustion, within the tumor microenvironment. Characterization of tumor-infiltrating B cells revealed clear evidence of antigen exposure, in that the cardinal features of an antigen-driven B cell response were present, including somatic mutation, clonal expansion, intraclonal variation and isotype switching. Collectively, our results point to an adaptive immune response occurring within the OSCC microenvironment, which may be sustained by the expression of specific antigens in the tumor. PMID:26815146

  18. Sequential transcriptional changes dictate safe and effective antigen-specific immunotherapy

    PubMed Central

    Burton, Bronwen R.; Britton, Graham J.; Fang, Hai; Verhagen, Johan; Smithers, Ben; Sabatos-Peyton, Catherine A.; Carney, Laura J.; Gough, Julian; Strobel, Stephan; Wraith, David C.

    2014-01-01

    Antigen-specific immunotherapy combats autoimmunity or allergy by reinstating immunological tolerance to target antigens without compromising immune function. Optimization of dosing strategy is critical for effective modulation of pathogenic CD4+ T-cell activity. Here we report that dose escalation is imperative for safe, subcutaneous delivery of the high self-antigen doses required for effective tolerance induction and elicits anergic, interleukin (IL)-10-secreting regulatory CD4+ T cells. Analysis of the CD4+ T-cell transcriptome, at consecutive stages of escalating dose immunotherapy, reveals progressive suppression of transcripts positively regulating inflammatory effector function and repression of cell cycle pathways. We identify transcription factors, c-Maf and NFIL3, and negative co-stimulatory molecules, LAG-3, TIGIT, PD-1 and TIM-3, which characterize this regulatory CD4+ T-cell population and whose expression correlates with the immunoregulatory cytokine IL-10. These results provide a rationale for dose escalation in T-cell-directed immunotherapy and reveal novel immunological and transcriptional signatures as surrogate markers of successful immunotherapy. PMID:25182274

  19. Molecular analysis of tumor-promoting CD8+ T cells in two-stage cutaneous chemical carcinogenesis.

    PubMed

    Kwong, Bernice Y; Roberts, Scott J; Silberzahn, Tobias; Filler, Renata B; Neustadter, Jason H; Galan, Anjela; Reddy, Swapna; Lin, William M; Ellis, Peter D; Langford, Cordelia F; Hayday, Adrian C; Girardi, Michael

    2010-06-01

    T-pro are tumor-infiltrating TCRalphabeta(+)CD8(+) cells of reduced cytotoxic potential that promote experimental two-stage chemical cutaneous carcinogenesis. Toward understanding their mechanism of action, this study uses whole-genome expression analysis to compare T-pro with systemic CD8(+) T cells from multiple groups of tumor-bearing mice. T-pro show an overt T helper 17-like profile (high retinoic acid-related orphan receptor-(ROR)gammat, IL-17A, IL-17F; low T-bet and eomesodermin), regulatory potential (high FoxP3, IL-10, Tim-3), and transcripts encoding epithelial growth factors (amphiregulin, Gro-1, Gro-2). Tricolor flow cytometry subsequently confirmed the presence of TCRbeta(+) CD8(+) IL-17(+) T cells among tumor-infiltrating lymphocytes (TILs). Moreover, a time-course analysis of independent TIL isolates from papillomas versus carcinomas exposed a clear association of the "T-pro phenotype" with malignant progression. This molecular characterization of T-pro builds a foundation for elucidating the contributions of inflammation to cutaneous carcinogenesis, and may provide useful biomarkers for cancer immunotherapy in which the widely advocated use of tumor-specific CD8(+) cytolytic T cells should perhaps accommodate the cells' potential corruption toward the T-pro phenotype. The data are also likely germane to psoriasis, in which the epidermis may be infiltrated by CD8(+) IL-17-producing T cells. PMID:19924136

  20. CD3brightCD56+ T cells associate with pegylated interferon-alpha treatment nonresponse in chronic hepatitis B patients

    PubMed Central

    Guo, Chuang; Shen, Xiaokun; Fu, Binqing; Liu, Yanyan; Chen, Yongyan; Ni, Fang; Ye, Ying; Sun, Rui; Li, Jiabin; Tian, Zhigang; Wei, Haiming

    2016-01-01

    Chronic hepatitis B (CHB) infection is a serious and prevalent health concern worldwide, and the development of effective drugs and strategies to combat this disease is urgently needed. Currently, pegylated interferon-alpha (peg-IFNα) and nucleoside/nucleotide analogues (NA) are the most commonly prescribed treatments. However, sustained response rates in patients remain low, and the reasons are not well understood. Here, we observed that CHB patients preferentially harbored CD3brightCD56+ T cells, a newly identified CD56+ T cell population. Patients with this unique T cell population exhibited relatively poor responses to peg-IFNα treatment. CD3brightCD56+ T cells expressed remarkably high levels of the inhibitory molecule NKG2A as well as low levels of CD8. Even if patients were systematically treated with peg-IFNα, CD3brightCD56+ T cells remained in an inhibitory state throughout treatment and exhibited suppressed antiviral function. Furthermore, peg-IFNα treatment rapidly increased inhibitory TIM-3 expression on CD3brightCD56+ T cells, which negatively correlated with IFNγ production and might have led to their dysfunction. This study identified a novel CD3brightCD56+ T cell population preferentially shown in CHB patients, and indicated that the presence of CD3brightCD56+ T cells in CHB patients may be useful as a new indicator associated with poor therapeutic responses to peg-IFNα treatment. PMID:27174425

  1. Broad spectrum activity of a lectin-like bacterial serine protease family on human leukocytes.

    PubMed

    Ayala-Lujan, Jorge Luis; Vijayakumar, Vidhya; Gong, Mei; Smith, Rachel; Santiago, Araceli E; Ruiz-Perez, Fernando

    2014-01-01

    The serine protease autotransporter from Enterobacteriaceae (SPATE) family, which number more than 25 proteases with apparent diverse functions, have been phylogenetically divided into two distinct classes, designated 1 and 2. We recently demonstrated that Pic and Tsh, two members of the class-2 SPATE family produced by intestinal and extraintestinal pathogenic E. coli, were able to cleave a number of O-glycosylated proteins on neutrophils and lymphocytes resulting in impaired leukocyte functions. Here we show that most members of the class-2 SPATE family have lectin-like properties and exhibit differential protease activity reliant on glycoprotein type and cell lineage. Protease activity was seen in virtually all tested O-glycosylated proteins including CD34, CD55, CD164, TIM1, TIM3, TIM4 and C1-INH. We also show that although SPATE proteins bound and cleaved glycoproteins more efficiently on granulocytes and monocytes, they also targeted glycoproteins on B, T and natural killer lymphocytes. Finally, we found that the characteristic domain-2 of class-2 SPATEs is not required for glycoprotease activity, but single amino acid mutations in Pic domain-1 to those residues naturally occurring in domain-1 of SepA, were sufficient to hamper Pic glycoprotease activity. This study shows that most class-2 SPATEs have redundant activities and suggest that they may function as immunomodulators at several levels of the immune system. PMID:25251283

  2. Immune-mediated antitumor effect by type 2 diabetes drug, metformin

    PubMed Central

    Eikawa, Shingo; Nishida, Mikako; Mizukami, Shusaku; Yamazaki, Chihiro; Nakayama, Eiichi; Udono, Heiichiro

    2015-01-01

    Metformin, a prescribed drug for type 2 diabetes, has been reported to have anti-cancer effects; however, the underlying mechanism is poorly understood. Here we show that this mechanism may be immune-mediated. Metformin enabled normal but not T-cell–deficient SCID mice to reject solid tumors. In addition, it increased the number of CD8+ tumor-infiltrating lymphocytes (TILs) and protected them from apoptosis and exhaustion characterized by decreased production of IL-2, TNFα, and IFNγ. CD8+ TILs capable of producing multiple cytokines were mainly PD-1−Tim-3+, an effector memory subset responsible for tumor rejection. Combined use of metformin and cancer vaccine improved CD8+ TIL multifunctionality. The adoptive transfer of antigen-specific CD8+ T cells treated with metformin concentrations as low as 10 μM showed efficient migration into tumors while maintaining multifunctionality in a manner sensitive to the AMP-activated protein kinase (AMPK) inhibitor compound C. Therefore, a direct effect of metformin on CD8+ T cells is critical for protection against the inevitable functional exhaustion in the tumor microenvironment. PMID:25624476

  3. HMGB1: The Central Cytokine for All Lymphoid Cells

    PubMed Central

    Li, Guanqiao; Liang, Xiaoyan; Lotze, Michael T.

    2013-01-01

    High-mobility group box 1 (HMGB1) is a leaderless cytokine, like the IL-1 and FGF family members, that has primary roles within the nucleus and the cytosol. Within the nucleus, it serves as another guardian of the genome, protecting it from oxidant injury and promoting access to transcriptional complexes such as nuclear hormone/nuclear hormone receptors and p53/p73 complexes. Within the cytosol it promotes autophagy and recruitment of the myddosome to Toll-like receptor (TLR) 9 vesicular compartments. Outside of the cell, it can either bind to specific receptors itself, or with high affinity to DNA, nucleosomes, IL-1β, lipopolysaccharide, and lipoteichoic acid to mediate responses in specific physiological or pathological conditions. Currently identified receptors include TLR2, TLR4, the receptor for advanced glycation end products, CD24-Siglec G/10, chemokine CXC receptor 4, and TIM-3. In terms of its effects or functions within lymphoid cells, HMGB1 is principally secreted from mature dendritic cells (DCs) to promote T-cell and B-cell reactivity and expansion and from activated natural killer cells to promote DC maturation during the afferent immune response. Some studies suggest that its primary role in the setting of chronic inflammation is to promote immunosuppression. As such, HMGB1 is a central cytokine for all lymphoid cells playing a role complementary to its better studied role in myeloid cells. PMID:23519706

  4. Combining Regulatory T Cell Depletion and Inhibitory Receptor Blockade Improves Reactivation of Exhausted Virus-Specific CD8+ T Cells and Efficiently Reduces Chronic Retroviral Loads

    PubMed Central

    Dietze, Kirsten K.; Zelinskyy, Gennadiy; Liu, Jia; Kretzmer, Freya; Schimmer, Simone; Dittmer, Ulf

    2013-01-01

    Chronic infections with human viruses, such as HIV and HCV, or mouse viruses, such as LCMV or Friend Virus (FV), result in functional exhaustion of CD8+ T cells. Two main mechanisms have been described that mediate this exhaustion: expression of inhibitory receptors on CD8+ T cells and expansion of regulatory T cells (Tregs) that suppress CD8+ T cell activity. Several studies show that blockage of one of these pathways results in reactivation of CD8+ T cells and partial reduction in chronic viral loads. Using blocking antibodies against PD-1 ligand and Tim-3 and transgenic mice in which Tregs can be selectively ablated, we compared these two treatment strategies and combined them for the first time in a model of chronic retrovirus infection. Blocking inhibitory receptors was more efficient than transient depletion of Tregs in reactivating exhausted CD8+ T cells and reducing viral set points. However, a combination therapy was superior to any single treatment and further augmented CD8+ T cell responses and resulted in a sustained reduction in chronic viral loads. These results demonstrate that Tregs and inhibitory receptors are non-overlapping factors in the maintenance of chronic viral infections and that immunotherapies targeting both pathways may be a promising strategy to treat chronic infectious diseases. PMID:24339778

  5. Role of Regulatory T Cells and Inhibitory Molecules in the Development of Immune Exhaustion During Human Immunodeficiency Virus Type 1 Infection.

    PubMed

    Gonzalez, Sandra Milena; Zapata, Wildeman; Rugeles, María Teresa

    2016-01-01

    One of the key hallmarks of chronic human immunodeficiency virus type 1 (HIV-1) infection is the persistent immune activation triggered since early stages of the infection, followed by the development of an exhaustion phenomena, which leads to the inability of immune cells to respond appropriately to the virus and other pathogens, constituting the acquired immunodeficiency syndrome (AIDS); this exhausting state is characterized by a loss of effector functions of immune cells such as proliferation, production of cytokine, as well as cytotoxic potential and it has been attributable to an increased response of regulatory T cells and recently also to the expression in different cell populations of inhibitory molecules, such as programmed death receptor-1 (PD-1), cytotoxic T lymphocyte antigen-4 (CTLA-4), T cell immunoglobulin-3 (Tim-3), and lymphocyte activation gene-3 (LAG-3). The importance of these molecules relies on the possibility to restore the immune response once these molecules are blocked, constituting a potential therapeutic target for treatment during HIV infection. In this regard, we explored the available data evaluating the functional role of Treg cells and inhibitory molecules during the infection in both blood and gut-associated lymphoid tissue (GALT) and their contribution to the development of immune exhaustion and progression to AIDS, as well as their therapeutic potential. PMID:26566019

  6. Galectin-9 is Involved in Immunosuppression Mediated by Human Bone Marrow-derived Clonal Mesenchymal Stem Cells.

    PubMed

    Kim, Si-Na; Lee, Hyun-Joo; Jeon, Myung-Shin; Yi, TacGhee; Song, Sun U

    2015-10-01

    Bone marrow-derived mesenchymal stem cells (MSCs) have immunomodulatory properties and can suppress exaggerated pro-inflammatory immune responses. Although the exact mechanisms remain unclear, a variety of soluble factors are known to contribute to MSC-mediated immunosuppression. However, functional redundancy in the immunosuppressive properties of MSCs indicates that other uncharacterized factors could be involved. Galectin-9, a member of the β-galactoside binding galectin family, has emerged as an important regulator of innate and adaptive immunity. We examined whether galectin-9 contributes to MSC-mediated immunosuppression. Galectin-9 was strongly induced and secreted from human MSCs upon stimulation with pro-inflammatory cytokines. An in vitro immunosuppression assay using a knockdown approach revealed that galectin-9-deficient MSCs do not exert immunosuppressive activity. We also provided evidence that galectin-9 may contribute to MSC-mediated immunosuppression by binding to its receptor, TIM-3, expressed on activated lymphocytes, leading to apoptotic cell death of activated lymphocytes. Taken together, our findings demonstrate that galectin-9 is involved in MSC-mediated immunosuppression and represents a potential therapeutic factor for the treatment of inflammatory diseases. PMID:26557808

  7. CEACAM1 mediates B cell aggregation in central nervous system autoimmunity.

    PubMed

    Rovituso, Damiano M; Scheffler, Laura; Wunsch, Marie; Kleinschnitz, Christoph; Dörck, Sebastian; Ulzheimer, Jochen; Bayas, Antonios; Steinman, Lawrence; Ergün, Süleyman; Kuerten, Stefanie

    2016-01-01

    B cell aggregates in the central nervous system (CNS) have been associated with rapid disease progression in patients with multiple sclerosis (MS). Here we demonstrate a key role of carcinoembryogenic antigen-related cell adhesion molecule1 (CEACAM1) in B cell aggregate formation in MS patients and a B cell-dependent mouse model of MS. CEACAM1 expression was increased on peripheral blood B cells and CEACAM1(+) B cells were present in brain infiltrates of MS patients. Administration of the anti-CEACAM1 antibody T84.1 was efficient in blocking aggregation of B cells derived from MS patients. Along these lines, application of the monoclonal anti-CEACAM1 antibody mCC1 was able to inhibit CNS B cell aggregate formation and significantly attenuated established MS-like disease in mice in the absence of any adverse effects. CEACAM1 was co-expressed with the regulator molecule T cell immunoglobulin and mucin domain -3 (TIM-3) on B cells, a novel molecule that has recently been described to induce anergy in T cells. Interestingly, elevated coexpression on B cells coincided with an autoreactive T helper cell phenotype in MS patients. Overall, these data identify CEACAM1 as a clinically highly interesting target in MS pathogenesis and open new therapeutic avenues for the treatment of the disease. PMID:27435215

  8. VEGF-A modulates expression of inhibitory checkpoints on CD8+ T cells in tumors

    PubMed Central

    Voron, Thibault; Colussi, Orianne; Marcheteau, Elie; Pernot, Simon; Nizard, Mevyn; Pointet, Anne-Laure; Latreche, Sabrina; Bergaya, Sonia; Benhamouda, Nadine; Tanchot, Corinne; Stockmann, Christian; Combe, Pierre; Berger, Anne; Zinzindohoue, Franck; Yagita, Hideo; Tartour, Eric; Terme, Magali

    2015-01-01

    Immune escape is a prerequisite for tumor development. To avoid the immune system, tumors develop different mechanisms, including T cell exhaustion, which is characterized by expression of immune inhibitory receptors, such as PD-1, CTLA-4, Tim-3, and a progressive loss of function. The recent development of therapies targeting PD-1 and CTLA-4 have raised great interest since they induced long-lasting objective responses in patients suffering from advanced metastatic tumors. However, the regulation of PD-1 expression, and thereby of exhaustion, is unclear. VEGF-A, a proangiogenic molecule produced by the tumors, plays a key role in the development of an immunosuppressive microenvironment. We report in the present work that VEGF-A produced in the tumor microenvironment enhances expression of PD-1 and other inhibitory checkpoints involved in CD8+ T cell exhaustion, which could be reverted by anti-angiogenic agents targeting VEGF-A–VEGFR. In view of these results, association of anti-angiogenic molecules with immunomodulators of inhibitory checkpoints may be of particular interest in VEGF-A-producing tumors. PMID:25601652

  9. Specific CD8(+) T cell response immunotherapy for hepatocellular carcinoma and viral hepatitis.

    PubMed

    Moreno-Cubero, Elia; Larrubia, Juan-Ramón

    2016-07-28

    Hepatocellular carcinoma (HCC), chronic hepatitis B (CHB) and chronic hepatitis C (CHC) are characterized by exhaustion of the specific CD8(+) T cell response. This process involves enhancement of negative co-stimulatory molecules, such as programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte antigen-4 (CTLA-4), 2B4, Tim-3, CD160 and LAG-3, which is linked to intrahepatic overexpression of some of the cognate ligands, such as PD-L1, on antigen presenting cells and thereby favouring a tolerogenic environment. Therapies that disrupt these negative signalling mechanisms represent promising therapeutic tools with the potential to restore reactivity of the specific CD8(+) T cell response. In this review we discuss the impressive in vitro and in vivo results that have been recently achieved in HCC, CHB and CHC by blocking these negative receptors with monoclonal antibodies against these immune checkpoint modulators. The article mainly focuses on the role of CTLA-4 and PD-1 blocking monoclonal antibodies, the first ones to have reached clinical practice. The humanized monoclonal antibodies against CTLA-4 (tremelimumab and ipilimumab) and PD-1 (nivolumab and pembrolizumab) have yielded good results in testing of HCC and chronic viral hepatitis patients. Trelimumab, in particular, has shown a significant increase in the time to progression in HCC, while nivolumab has shown a remarkable effect on hepatitis C viral load reduction. The research on the role of ipilimumab, nivolumab and pembrolizumab on HCC is currently underway. PMID:27605882

  10. CD3(bright)CD56(+) T cells associate with pegylated interferon-alpha treatment nonresponse in chronic hepatitis B patients.

    PubMed

    Guo, Chuang; Shen, Xiaokun; Fu, Binqing; Liu, Yanyan; Chen, Yongyan; Ni, Fang; Ye, Ying; Sun, Rui; Li, Jiabin; Tian, Zhigang; Wei, Haiming

    2016-01-01

    Chronic hepatitis B (CHB) infection is a serious and prevalent health concern worldwide, and the development of effective drugs and strategies to combat this disease is urgently needed. Currently, pegylated interferon-alpha (peg-IFNα) and nucleoside/nucleotide analogues (NA) are the most commonly prescribed treatments. However, sustained response rates in patients remain low, and the reasons are not well understood. Here, we observed that CHB patients preferentially harbored CD3(bright)CD56(+) T cells, a newly identified CD56(+) T cell population. Patients with this unique T cell population exhibited relatively poor responses to peg-IFNα treatment. CD3(bright)CD56(+) T cells expressed remarkably high levels of the inhibitory molecule NKG2A as well as low levels of CD8. Even if patients were systematically treated with peg-IFNα, CD3(bright)CD56(+) T cells remained in an inhibitory state throughout treatment and exhibited suppressed antiviral function. Furthermore, peg-IFNα treatment rapidly increased inhibitory TIM-3 expression on CD3(bright)CD56(+) T cells, which negatively correlated with IFNγ production and might have led to their dysfunction. This study identified a novel CD3(bright)CD56(+) T cell population preferentially shown in CHB patients, and indicated that the presence of CD3(bright)CD56(+) T cells in CHB patients may be useful as a new indicator associated with poor therapeutic responses to peg-IFNα treatment. PMID:27174425

  11. Deletion of cyclooxygenase 2 in mouse mammary epithelial cells delays breast cancer onset through augmentation of type 1 immune responses in tumors

    PubMed Central

    Markosyan, Nune; Chen, Edward P.; Ndong, Victoire N.; Yao, Yubing; Sterner, Christopher J.; Chodosh, Lewis A.; Lawson, John A.; FitzGerald, Garret A.; Smyth, Emer M.

    2011-01-01

    Inhibition of cyclooxygenase (COX) 2, which is associated with >40% of breast cancers, decreases the risk of tumorigenesis and breast cancer recurrence. To study the role of COX-2 in breast cancer, we engineered mice that lack selectively mammary epithelial cell (MEC) COX-2 (COX-2 KOMEC). Compared with wild type (WT), MEC from COX-2 KOMEC mice expressed >90% less COX-2 messenger RNA (mRNA) and protein and produced 90% less of the dominant pro-oncogenic COX-2 product, prostaglandin (PG) E2. We confirmed COX-2 as the principle source of PGE2 in MEC treated with selective COX-2 and COX-1 inhibitors. Tumors were induced in mice using medroxyprogesterone acetate and 7,12-dimethylbenz[a]anthracene. Breast cancer onset was significantly delayed in COX-2 KOMEC compared with WT (P = 0.03), equivalent to the delay following systemic COX-2 inhibition with rofecoxib. Compared with WT, COX-2 KOMEC tumors showed increased mRNA for Caspase-3, Ki-67 and common markers for leukocytes (CD45) and macrophages (F4/80). Analysis of multiple markers/cytokines, namely CD86, inducible nitric oxide synthase (iNOS), interleukin-6, tumor necrosis factor α (TNFα) and Tim-3 indicated a shift toward antitumorigenic type 1 immune responses in COX-2 KOMEC tumors. Immunohistochemical analysis confirmed elevated expression of CD45, F4/80 and CD86 in COX-2 KOMEC tumors. Concordant with a role for COX-2 in restraining M1 macrophage polarization, CD86 and TNFα expression were offset by exogenous PGE2 in bone marrow-derived macrophages polarized in vitro to the M1 phenotype. Our data reveal the importance of epithelial COX-2 in tumor promotion and indicate that deletion of epithelial COX-2 may skew tumor immunity toward type 1 responses, coincident with delayed tumor development. PMID:21771729

  12. Progression of Lung Cancer Is Associated with Increased Dysfunction of T Cells Defined by Coexpression of Multiple Inhibitory Receptors.

    PubMed

    Thommen, Daniela S; Schreiner, Jens; Müller, Philipp; Herzig, Petra; Roller, Andreas; Belousov, Anton; Umana, Pablo; Pisa, Pavel; Klein, Christian; Bacac, Marina; Fischer, Ozana S; Moersig, Wolfgang; Savic Prince, Spasenija; Levitsky, Victor; Karanikas, Vaios; Lardinois, Didier; Zippelius, Alfred

    2015-12-01

    Dysfunctional T cells present in malignant lesions are characterized by a sustained and highly diverse expression of inhibitory receptors, also referred to as immune checkpoints. Yet, their relative functional significance in different cancer types remains incompletely understood. In this study, we provide a comprehensive characterization of the diversity and expression patterns of inhibitory receptors on tumor-infiltrating T cells from patients with non-small cell lung cancer. In spite of the large heterogeneity observed in the amount of PD-1, Tim-3, CTLA-4, LAG-3, and BTLA expressed on intratumoral CD8(+) T cells from 32 patients, a clear correlation was established between increased expression of these inhibitory coreceptors and progression of the disease. Notably, the latter was accompanied by a progressively impaired capacity of T cells to respond to polyclonal activation. Coexpression of several inhibitory receptors was gradually acquired, with early PD-1 and late LAG-3/BTLA expression. PD-1 blockade was able to restore T-cell function only in a subset of patients. A high percentage of PD-1(hi) T cells was correlated with poor restoration of T-cell function upon PD-1 blockade. Of note, PD-1(hi) expression marked a particularly dysfunctional T-cell subset characterized by coexpression of multiple inhibitory receptors and thus may assist in identifying patients likely to respond to inhibitory receptor-specific antibodies. Overall, these data may provide a framework for future personalized T-cell-based therapies aiming at restoration of tumor-infiltrating lymphocyte effector functions. PMID:26253731

  13. Impaired NK Cell Activation and Chemotaxis toward Dendritic Cells Exposed to Complement-Opsonized HIV-1

    PubMed Central

    Ellegård, Rada; Crisci, Elisa; Andersson, Jonas; Shankar, Esaki M.; Nyström, Sofia; Hinkula, Jorma

    2015-01-01

    Mucosa resident dendritic cells (DCs) may represent one of the first immune cells that HIV-1 encounters during sexual transmission. The virions in body fluids can be opsonized with complement factors because of HIV-mediated triggering of the complement cascade, and this appears to influence numerous aspects of the immune defense targeting the virus. One key attribute of host defense is the ability to attract immune cells to the site of infection. In this study, we investigated whether the opsonization of HIV with complement (C-HIV) or a mixture of complement and Abs (CI-HIV) affected the cytokine and chemokine responses generated by DCs, as well as their ability to attract other immune cells. We found that the expression levels of CXCL8, CXCL10, CCL3, and CCL17 were lowered after exposure to either C-HIV or CI-HIV relative to free HIV (F-HIV). DCs exposed to F-HIV induced higher cell migration, consisting mainly of NK cells, compared with opsonized virus, and the chemotaxis of NK cells was dependent on CCL3 and CXCL10. NK cell exposure to supernatants derived from HIV-exposed DCs showed that F-HIV induced phenotypic activation (e.g., increased levels of TIM3, CD69, and CD25) and effector function (e.g., production of IFNγ and killing of target cells) in NK cells, whereas C-HIV and CI-HIV did not. The impairment of NK cell recruitment by DCs exposed to complement-opsonized HIV and the lack of NK activation may contribute to the failure of innate immune responses to control HIV at the site of initial mucosa infection. PMID:26157174

  14. Increase in frequencies of circulating Th-17 cells correlates with microbial translocation, immune activation and exhaustion in HIV-1 infected patients with poor CD4 T-cell reconstitution.

    PubMed

    Valiathan, Ranjini; Asthana, Deshratn

    2016-05-01

    We analyzed the association of circulating Th-17 cells (cTh-17) with immune activation (IA), immune exhaustion (IE) and regulatory T-cells (T-regs) in 20 human immunodeficiency virus-1 (HIV-1) infected patients with impaired restoration of CD4 T-cell counts despite prolonged suppression of plasma viremia (discordant) and compared it with 20 HIV-1 infected patients showing good immunologic and virologic responses (concordant) following highly active antiretroviral therapy (HAART). Discordant HIV-1 infected patients showed significantly higher frequencies of cTh-17 cells compared to concordant patients and healthy controls after PMA+Ionomicin stimulation. Discordant patients also showed higher CD4 T-cell immune activation (HLA-DR+CD38+) than concordant patients which directly correlated with microbial translocation. Additionally, CD4 T-cells of discordant patients showed higher frequencies of CD4 T-cells expressing multiple immune exhaustion markers (Tim3+PD-1+) which correlated with immune activation indicating that combined analysis of inhibitory molecules along with PD-1 might be a better predictor for immune exhaustion of CD4 T-cells. Increased cTh-17 cell frequency correlated inversely with CD4 T-cell percentages and absolute counts and directly with CD4 T-cell immune activation and T-reg frequencies. Persistent CD4 T-cell immune activation might favor differentiation of activated CD4 T-cells toward cTh-17 phenotype in discordant patients. Discordant patients had significantly lower baseline CD4 T-cell counts and higher viral load at the initiation of HAART and higher immune activation and immune exhaustion after being on HAART for long time indicating that these factors might be associated with an increase in cTh-17 cell frequency, thus, increasing the risk of disease progression despite virologic control. PMID:26817581

  15. Shaping the Immune Landscape in Cancer by Galectin-Driven Regulatory Pathways.

    PubMed

    Rabinovich, Gabriel A; Conejo-García, José R

    2016-08-14

    Along with the discovery of tumor-driven inflammatory pathways, there has been a considerable progress over the past 10years in understanding the mechanisms leading to cancer immunosurveillance and immunoediting. Several regulatory pathways, typically involved in immune cell homeostasis, are co-opted by cancer cells to thwart the development of effective antitumor responses. These regulatory circuits include the engagement of inhibitory checkpoint pathways (CTLA-4, PD-1/PD-L1, LAG-3 and TIM-3), secretion of immunosuppressive cytokines (TGF-β, IL-10), and expansion and/or recruitment of myeloid or lymphoid regulatory cell populations. Elucidation of these pathways has inspired the design and implementation of novel immunotherapeutic modalities, which have already generated clinical benefits in an important number of cancer patients. Galectins, a family of glycan-binding proteins widely expressed in the tumor microenvironment (TME), have emerged as key players in immune evasion programs that differentially control the fate of effector and regulatory lymphoid and myeloid cell populations. How do galectins translate glycan-containing information into cellular programs that control immune regulatory cancer networks? Here, we uncover the selective roles of individual members of the galectin family in cancer-promoting inflammation, immunosuppression, and angiogenesis. Moreover, we highlight the relevance of corresponding glycosylated ligands and counter-receptors and the emerging function of these lectins as biological liaisons connecting commensal microbiota, systemic inflammation, and distal tumor growth. Understanding the molecular and cellular components of galectin-driven regulatory circuits, the implications of different glycosylation pathways in their functions and their clinical relevance in human cancer might lead to the development of new therapeutic approaches in a broad range of tumor types. PMID:27038510

  16. The adaptive evolution divergence of triosephosphate isomerases between parasitic and free-living flatworms and the discovery of a potential universal target against flatworm parasites.

    PubMed

    Chen, Bing; Wen, Jian-Fan

    2011-08-01

    Triosephosphate isomerase (TIM) is an important drug target or vaccine candidate for pathogenetic organisms such as schistosomes. Parasitic and free-living flatworms shared their last common ancestor but diverged from each other for adapting to parasitic and free-living lives afterwards, respectively. Therefore, adaptive evolution divergence must have occurred between them. Here, for the first time, TIMs were identified from three free-living planarian flatworms, namely Dugesia japonica, Dugesia ryukyuensis, and Schmidtea mediterranea. When these were compared with parasitic flatworms and other organisms, the following results were obtained: (1) planarian TIM genes each contain only one intron, while parasitic flatworm genes each contain other four introns, which are usually present in common metazoans, suggesting planarian-specific intron loss must have occurred; (2) planarian TIM protein sequences are more similar to those of vertebrates rather than to their parasitic relatives or other invertebrates. This implies that relatively rapid evolution occurred in parasitic flatworm TIMs; (3) All the investigated parasitic flatworm TIMs contain a unique tripeptide insert (SXD/E), which may imply its insertion importance to the adaptation of parasitic life. Moreover, our homology modeling results showed the insert region was largely surface-exposed and predicted to be of a B cell epitope location. Finally, the insert is located within one of the three regions previously suggested to be promising immunogenic epitopes in Schistosoma mansoni TIM. Therefore, this unique insert might be significant to developing new effective vaccines or specific drugs against all parasitic flatworm diseases such as schistosomiasis and taeniosis/cysticercosis. PMID:21246382

  17. Polyfunctional Melan-A-specific tumor-reactive CD8(+) T cells elicited by dacarbazine treatment before peptide-vaccination depends on AKT activation sustained by ICOS.

    PubMed

    Franzese, Ornella; Palermo, Belinda; Di Donna, Cosmo; Sperduti, Isabella; Ferraresi, Virginia; Stabile, Helena; Gismondi, Angela; Santoni, Angela; Nisticò, Paola

    2016-05-01

    The identification of activation pathways linked to antitumor T-cell polyfunctionality in long surviving patients is of great relevance in the new era of immunotherapy. We have recently reported that dacarbazine (DTIC) injected one day before peptide-vaccination plus IFN-α improves the antitumor lytic activity and enlarges the repertoire of Melan-A-specific T-cell clones, as compared with vaccination alone, impacting the overall survival of melanoma patients. To identify the mechanisms responsible for this improvement of the immune response, we have analyzed the endogenous and treatment-induced antigen (Ag)-specific response in a panel of Melan-A-specific CD8(+) T-cell clones in terms of differentiation phenotype, inhibitory receptor profile, polyfunctionality and AKT activation. Here, we show that Melan-A-specific CD8(+) T cells isolated from patients treated with chemoimmunotherapy possess a late differentiated phenotype as defined by the absence of CD28 and CD27 co-stimulatory molecules and high levels of LAG-3, TIM-3 and PD-1 inhibitory receptors. Nevertheless, they show higher proliferative potential and an improved antitumor polyfunctional effector profile in terms of co-production of TNF-α, IFNγ and Granzyme-B (GrB) compared with cells derived from patients treated with vaccination alone. Polyfunctionality is dependent on an active AKT signaling related to the engagement of the co-stimulatory molecule ICOS. We suggest that this phenotypic and functional signature is dictated by a fine-tuned balance between TCR triggering, AKT activation, co-stimulatory and inhibitory signals induced by chemoimmunotherapy and may be associated with antitumor T cells able to protect patients from tumor recurrence. PMID:27467927

  18. Manipulation of Regulatory Cells’ Responses to Treatments for Chronic Hepatitis B Virus Infection

    PubMed Central

    Tavakolpour, Soheil; Alavian, Seyed Moayed; Sali, Shahnaz

    2016-01-01

    Background Identification of effective treatments in hepatitis B virus (HBV) infection remains a controversial topic. Although the currently approved drugs for HBV control the disease’s progression and also limit associated outcomes, these drugs may not fully eradicate HBV infection. In addition to better managing patients with chronic hepatitis B (CHB) infection, the induction of seroclearance by these drugs has been a commonly discussed topic in recent years. Objectives In this study, we focused on treating CHB infection via the manipulation of T cells’ responses to identify possible approaches to cure CHB. Materials and Methods All studies relevant to the role of cellular and humoral responses in HBV infection (especially regulatory cells) were investigated via a systematic search of different databases, including PubMed, Scopus, and Google Scholar. Considering extracted data and also our unpublished data regarding the association between regulatory cytokines and CHB, we introduced a novel approach for the induction of seroclearance. Results Considering the increased levels of regulatory cytokines and also regulatory T cells (Tregs) during CHB, it seems that these cells are deeply involved in CHB infection. The inhibition of regulatory T cells may reverse the dysfunction of effector T cells in patients with CHB infection. In order to inhibit Tregs’ responses, different types of approaches could be employed to restore the impaired function of effector T cells. The blockade of IL-10, IL-35, CTLA-4, PD-1, and TIM-3 were discussed throughout this study. Regardless of the efficacy of these methods, CHB patients may experience serious liver injuries due to the cytotoxic action of CD8+ T cells. Antiviral therapy and a decrease in HBV DNA to undetectable levels could also significantly reduce the risk of the hepatitis B flare. Conclusions The inhibition of Tregs is a novel therapeutic approach to cure chronically HBV infected patients. However, further studies are

  19. An immunogenomic stratification of colorectal cancer: Implications for development of targeted immunotherapy

    PubMed Central

    Lal, Neeraj; Beggs, Andrew D; Willcox, Benjamin E; Middleton, Gary W

    2015-01-01

    Although tumor infiltrating lymphocyte (TIL) density is prognostic and predictive in colorectal cancer (CRC), the impact of tumor genetics upon colorectal immunobiology is unclear. Identification of genetic factors that influence the tumor immunophenotype is essential to improve the effectiveness of stratified immunotherapy approaches. We carried out a bioinformatics analysis of CRC data in The Cancer Genome Atlas (TCGA) involving two-dimensional hierarchical clustering to define an immune signature that we used to characterize the immune response across key patient groups. An immune signature termed The Co-ordinate Immune Response Cluster (CIRC) comprising 28 genes was coordinately regulated across the patient population. Four patient groups were delineated on the basis of cluster expression. Group A, which was heavily enriched for patients with microsatellite instability (MSI-H) and POL mutations, exhibited high CIRC expression, including the presence of several inhibitory molecules: CTLA4, PDL1, PDL2, LAG3, and TIM3. In contrast, RAS mutation was enriched in patient groups with lower CIRC expression. This work links the genetics and immunobiology of colorectal tumorigenesis, with implications for the development of stratified immunotherapeutic approaches. Microsatellite instability and POL mutations are linked with high mutational burden and high immune infiltration, but the coordinate expression of inhibitory pathways observed suggests combination checkpoint blockade therapy may be required to improve efficacy. In contrast, RAS mutant tumors predict for a relatively poor immune infiltration and low inhibitory molecule expression. In this setting, checkpoint blockade may be less efficacious, highlighting a requirement for novel strategies in this patient group. PMID:25949894

  20. CD4+ T Cells Expressing PD-1, TIGIT and LAG-3 Contribute to HIV Persistence during ART.

    PubMed

    Fromentin, Rémi; Bakeman, Wendy; Lawani, Mariam B; Khoury, Gabriela; Hartogensis, Wendy; DaFonseca, Sandrina; Killian, Marisela; Epling, Lorrie; Hoh, Rebecca; Sinclair, Elizabeth; Hecht, Frederick M; Bacchetti, Peter; Deeks, Steven G; Lewin, Sharon R; Sékaly, Rafick-Pierre; Chomont, Nicolas

    2016-07-01

    HIV persists in a small pool of latently infected cells despite antiretroviral therapy (ART). Identifying cellular markers expressed at the surface of these cells may lead to novel therapeutic strategies to reduce the size of the HIV reservoir. We hypothesized that CD4+ T cells expressing immune checkpoint molecules would be enriched in HIV-infected cells in individuals receiving suppressive ART. Expression levels of 7 immune checkpoint molecules (PD-1, CTLA-4, LAG-3, TIGIT, TIM-3, CD160 and 2B4) as well as 4 markers of HIV persistence (integrated and total HIV DNA, 2-LTR circles and cell-associated unspliced HIV RNA) were measured in PBMCs from 48 virally suppressed individuals. Using negative binomial regression models, we identified PD-1, TIGIT and LAG-3 as immune checkpoint molecules positively associated with the frequency of CD4+ T cells harboring integrated HIV DNA. The frequency of CD4+ T cells co-expressing PD-1, TIGIT and LAG-3 independently predicted the frequency of cells harboring integrated HIV DNA. Quantification of HIV genomes in highly purified cell subsets from blood further revealed that expressions of PD-1, TIGIT and LAG-3 were associated with HIV-infected cells in distinct memory CD4+ T cell subsets. CD4+ T cells co-expressing the three markers were highly enriched for integrated viral genomes (median of 8.2 fold compared to total CD4+ T cells). Importantly, most cells carrying inducible HIV genomes expressed at least one of these markers (median contribution of cells expressing LAG-3, PD-1 or TIGIT to the inducible reservoir = 76%). Our data provide evidence that CD4+ T cells expressing PD-1, TIGIT and LAG-3 alone or in combination are enriched for persistent HIV during ART and suggest that immune checkpoint blockers directed against these receptors may represent valuable tools to target latently infected cells in virally suppressed individuals. PMID:27415008

  1. Impaired NK Cell Activation and Chemotaxis toward Dendritic Cells Exposed to Complement-Opsonized HIV-1.

    PubMed

    Ellegård, Rada; Crisci, Elisa; Andersson, Jonas; Shankar, Esaki M; Nyström, Sofia; Hinkula, Jorma; Larsson, Marie

    2015-08-15

    Mucosa resident dendritic cells (DCs) may represent one of the first immune cells that HIV-1 encounters during sexual transmission. The virions in body fluids can be opsonized with complement factors because of HIV-mediated triggering of the complement cascade, and this appears to influence numerous aspects of the immune defense targeting the virus. One key attribute of host defense is the ability to attract immune cells to the site of infection. In this study, we investigated whether the opsonization of HIV with complement (C-HIV) or a mixture of complement and Abs (CI-HIV) affected the cytokine and chemokine responses generated by DCs, as well as their ability to attract other immune cells. We found that the expression levels of CXCL8, CXCL10, CCL3, and CCL17 were lowered after exposure to either C-HIV or CI-HIV relative to free HIV (F-HIV). DCs exposed to F-HIV induced higher cell migration, consisting mainly of NK cells, compared with opsonized virus, and the chemotaxis of NK cells was dependent on CCL3 and CXCL10. NK cell exposure to supernatants derived from HIV-exposed DCs showed that F-HIV induced phenotypic activation (e.g., increased levels of TIM3, CD69, and CD25) and effector function (e.g., production of IFNγ and killing of target cells) in NK cells, whereas C-HIV and CI-HIV did not. The impairment of NK cell recruitment by DCs exposed to complement-opsonized HIV and the lack of NK activation may contribute to the failure of innate immune responses to control HIV at the site of initial mucosa infection. PMID:26157174

  2. CD4+ primary T cells expressing HCV-core protein upregulate Foxp3 and IL-10, suppressing CD4 and CD8 T cells.

    PubMed

    Fernandez-Ponce, Cecilia; Dominguez-Villar, Margarita; Aguado, Enrique; Garcia-Cozar, Francisco

    2014-01-01

    Adaptive T cell responses are critical for controlling HCV infection. While there is clinical evidence of a relevant role for regulatory T cells in chronic HCV-infected patients, based on their increased number and function; mechanisms underlying such a phenomena are still poorly understood. Accumulating evidence suggests that proteins from Hepatitis C virus can suppress host immune responses. We and others have shown that HCV is present in CD4+ lymphocytes from chronically infected patients and that HCV-core protein induces a state of unresponsiveness in the CD4+ tumor cell line Jurkat. Here we show that CD4+ primary T cells lentivirally transduced with HCV-core, not only acquire an anergic phenotype but also inhibit IL-2 production and proliferation of bystander CD4+ or CD8+ T cells in response to anti-CD3 plus anti-CD28 stimulation. Core-transduced CD4+ T cells show a phenotype characterized by an increased basal secretion of the regulatory cytokine IL-10, a decreased IFN-γ production upon stimulation, as well as expression of regulatory T cell markers, CTLA-4, and Foxp3. A significant induction of CD4+CD25+CD127(low)PD-1(high)TIM-3(high) regulatory T cells with an exhausted phenotype was also observed. Moreover, CCR7 expression decreased in HCV-core expressing CD4+ T cells explaining their sequestration in inflamed tissues such as the infected liver. This work provides a new perspective on de novo generation of regulatory CD4+ T cells in the periphery, induced by the expression of a single viral protein. PMID:24465502

  3. Implication of combined PD-L1/PD-1 blockade with cytokine-induced killer cells as a synergistic immunotherapy for gastrointestinal cancer

    PubMed Central

    Geng, Ruixuan; Ge, Xiaoxiao; Tang, Wenbo; Chang, Jinjia; Wu, Zheng; Liu, Xinyang; Lin, Ying; Zhang, Zhe; Li, Jin

    2016-01-01

    Cytokine-induced killer (CIK) cells represent a realistic approach in cancer immunotherapy with confirmed survival benefits in the context of metastatic solid tumors. However, therapeutic effects are limited to a fraction of patients. In this study, immune-resistance elements and ideal combination therapies were explored. Initially, phenotypic analysis was performed to document CD3, CD56, NKG2D, DNAM-1, PD-L1, PD-1, CTLA-4, TIM-3, 2B4, and LAG-3 on CIK cells. Upon engagement of CIK cells with the tumor cells, expression of PD-1 on CIK cells and PD-L1 on both cells were up-regulated. Over-expression of PD-L1 levels on tumor cells via lentiviral transduction inhibited tumoricidal activity of CIK cells, and neutralizing of PD-L1/PD-1 signaling axis could enhance their tumor-killing effect. Conversely, blockade of NKG2D, a major activating receptor of CIK cells, largely caused dysfunction of CIK cells. Functional study showed an increase of NKG2D levels along with PD-L1/PD-1 blockade in the presence of other immune effector molecule secretion. Additionally, combined therapy of CIK infusion and PD-L1/PD-1 blockade caused a delay of in vivo tumor growth and exhibited a survival advantage over untreated mice. These results provide a preclinical proof-of-concept for simultaneous PD-L1/PD-1 pathways blockade along with CIK infusion as a novel immunotherapy for unresectable cancers. PMID:26871284

  4. CD4+ T Cells Expressing PD-1, TIGIT and LAG-3 Contribute to HIV Persistence during ART

    PubMed Central

    Fromentin, Rémi; Bakeman, Wendy; Lawani, Mariam B.; Khoury, Gabriela; Hartogensis, Wendy; DaFonseca, Sandrina; Killian, Marisela; Epling, Lorrie; Hoh, Rebecca; Sinclair, Elizabeth; Hecht, Frederick M.; Bacchetti, Peter; Deeks, Steven G.; Lewin, Sharon R.; Sékaly, Rafick-Pierre; Chomont, Nicolas

    2016-01-01

    HIV persists in a small pool of latently infected cells despite antiretroviral therapy (ART). Identifying cellular markers expressed at the surface of these cells may lead to novel therapeutic strategies to reduce the size of the HIV reservoir. We hypothesized that CD4+ T cells expressing immune checkpoint molecules would be enriched in HIV-infected cells in individuals receiving suppressive ART. Expression levels of 7 immune checkpoint molecules (PD-1, CTLA-4, LAG-3, TIGIT, TIM-3, CD160 and 2B4) as well as 4 markers of HIV persistence (integrated and total HIV DNA, 2-LTR circles and cell-associated unspliced HIV RNA) were measured in PBMCs from 48 virally suppressed individuals. Using negative binomial regression models, we identified PD-1, TIGIT and LAG-3 as immune checkpoint molecules positively associated with the frequency of CD4+ T cells harboring integrated HIV DNA. The frequency of CD4+ T cells co-expressing PD-1, TIGIT and LAG-3 independently predicted the frequency of cells harboring integrated HIV DNA. Quantification of HIV genomes in highly purified cell subsets from blood further revealed that expressions of PD-1, TIGIT and LAG-3 were associated with HIV-infected cells in distinct memory CD4+ T cell subsets. CD4+ T cells co-expressing the three markers were highly enriched for integrated viral genomes (median of 8.2 fold compared to total CD4+ T cells). Importantly, most cells carrying inducible HIV genomes expressed at least one of these markers (median contribution of cells expressing LAG-3, PD-1 or TIGIT to the inducible reservoir = 76%). Our data provide evidence that CD4+ T cells expressing PD-1, TIGIT and LAG-3 alone or in combination are enriched for persistent HIV during ART and suggest that immune checkpoint blockers directed against these receptors may represent valuable tools to target latently infected cells in virally suppressed individuals. PMID:27415008

  5. Polyfunctional Melan-A-specific tumor-reactive CD8+ T cells elicited by dacarbazine treatment before peptide-vaccination depends on AKT activation sustained by ICOS

    PubMed Central

    Franzese, Ornella; Palermo, Belinda; Di Donna, Cosmo; Sperduti, Isabella; Ferraresi, Virginia; Stabile, Helena; Gismondi, Angela; Santoni, Angela; Nisticò, Paola

    2016-01-01

    ABSTRACT The identification of activation pathways linked to antitumor T-cell polyfunctionality in long surviving patients is of great relevance in the new era of immunotherapy. We have recently reported that dacarbazine (DTIC) injected one day before peptide-vaccination plus IFN-α improves the antitumor lytic activity and enlarges the repertoire of Melan-A-specific T-cell clones, as compared with vaccination alone, impacting the overall survival of melanoma patients. To identify the mechanisms responsible for this improvement of the immune response, we have analyzed the endogenous and treatment-induced antigen (Ag)-specific response in a panel of Melan-A-specific CD8+ T-cell clones in terms of differentiation phenotype, inhibitory receptor profile, polyfunctionality and AKT activation. Here, we show that Melan-A-specific CD8+ T cells isolated from patients treated with chemoimmunotherapy possess a late differentiated phenotype as defined by the absence of CD28 and CD27 co-stimulatory molecules and high levels of LAG-3, TIM-3 and PD-1 inhibitory receptors. Nevertheless, they show higher proliferative potential and an improved antitumor polyfunctional effector profile in terms of co-production of TNF-α, IFNγ and Granzyme-B (GrB) compared with cells derived from patients treated with vaccination alone. Polyfunctionality is dependent on an active AKT signaling related to the engagement of the co-stimulatory molecule ICOS. We suggest that this phenotypic and functional signature is dictated by a fine-tuned balance between TCR triggering, AKT activation, co-stimulatory and inhibitory signals induced by chemoimmunotherapy and may be associated with antitumor T cells able to protect patients from tumor recurrence. PMID:27467927

  6. TIGIT and PD-1 impair tumor antigen–specific CD8+ T cells in melanoma patients

    PubMed Central

    Chauvin, Joe-Marc; Pagliano, Ornella; Fourcade, Julien; Sun, Zhaojun; Wang, Hong; Sander, Cindy; Kirkwood, John M.; Chen, Tseng-hui Timothy; Maurer, Mark; Korman, Alan J.; Zarour, Hassane M.

    2015-01-01

    T cell Ig and ITIM domain (TIGIT) is an inhibitory receptor expressed by activated T cells, Tregs, and NK cells. Here, we determined that TIGIT is upregulated on tumor antigen–specific (TA-specific) CD8+ T cells and CD8+ tumor-infiltrating lymphocytes (TILs) from patients with melanoma, and these TIGIT-expressing CD8+ T cells often coexpress the inhibitory receptor PD-1. Moreover, CD8+ TILs from patients exhibited downregulation of the costimulatory molecule CD226, which competes with TIGIT for the same ligand, supporting a TIGIT/CD226 imbalance in metastatic melanoma. TIGIT marked early T cell activation and was further upregulated by T cells upon PD-1 blockade and in dysfunctional PD-1+TIM-3+ TA-specific CD8+ T cells. PD-1+TIGIT+, PD-1–TIGIT+, and PD-1+TIGIT– CD8+ TILs had similar functional capacities ex vivo, suggesting that TIGIT alone, or together with PD-1, is not indicative of T cell dysfunction. However, in the presence of TIGIT ligand–expressing cells, TIGIT and PD-1 blockade additively increased proliferation, cytokine production, and degranulation of both TA-specific CD8+ T cells and CD8+ TILs. Collectively, our results show that TIGIT and PD-1 regulate the expansion and function of TA-specific CD8+ T cells and CD8+ TILs in melanoma patients and suggest that dual TIGIT and PD-1 blockade should be further explored to elicit potent antitumor CD8+ T cell responses in patients with advanced melanoma. PMID:25866972

  7. Theoretical and experimental investigations on molecular structure of 7-Chloro-9-phenyl-2,3-dihydroacridin-4(1H)-one with cytotoxic studies

    NASA Astrophysics Data System (ADS)

    Satheeshkumar, Rajendran; Shankar, Ramasamy; Kaminsky, Werner; Kalaiselvi, Sivalingam; Padma, Viswanadha Vijaya; Rajendra Prasad, Karnam Jayarampillai

    2016-04-01

    7-Chloro-9-phenyl-2,3-dihydroacridin-4(1H)-one (3) is synthesized from 2-amino-5-chlorobenzophenone (1) and 1,2-cyclohexanedione (2) in the presence of catalyst InCl3. FT-IR, FT-Raman and FT-NMR spectra of molecule 3 have been recorded and the structure was confirmed by single crystal X-ray diffraction. CDCl3 and DMSO-d6 FT-NMR spectra and 1H and 13C NMR chemical shifts have been measured in molecule 3 and calculated at the B3LYP/6-311G (d,p) and MO6-2x/6-311G (d,p) levels of theory. Similarly calculated vibrational frequencies were found in good agreement with experimental findings. The optimized geometry of molecule 3 was compared with experimental XRD values. DFT calculations of the molecular electrostatic potential (MEP) and HOMO - LUMO frontier orbitals identified chemically active sites of molecule 3 responsible for its bioactivity. The title compound, 3 exhibits higher cytotoxicity in Human breast cancer cells (MCF-7) compared to human lung adenocarcinoma cells (A549).

  8. Biology Labs That Work: The Best of How-To-Do-Its. Volume II.

    ERIC Educational Resources Information Center

    Black, Suzanne, Ed.; Moore, Randy, Ed.; Haugen, Heidi, Ed.

    This selected collection of How-To-Do-It articles published in the American Biology Teacher during the past six years presents experiments that can be conducted safely under properly trained and responsible teacher supervision. Contents include: (1) "General Biology and the Nature of Science"; (2) "Cells and Molecules"; (3) "Microbes and Fungi";…

  9. Biochemical methods for quantifying sphingolipids: ceramide, sphingosine, sphingosine kinase-1 activity, and sphingosine-1-phosphate.

    PubMed

    Brizuela, Leyre; Cuvillier, Olivier

    2012-01-01

    Sphingolipids (ceramide, sphingosine, and sphingosine-1-phosphate) are bioactive lipids with important biological functions in proliferation, apoptosis, angiogenesis, and inflammation. Herein, we describe easy and rapid biochemical methods with the use of radiolabeled molecules ((3)H, (32)P) for their mass determination. Quantitation of sphingosine kinase-1 activity, the most studied isoform, is also included. PMID:22528435

  10. Electronic and Nuclear Factors in Charge and Excitation Transfer

    SciTech Connect

    Piotr Piotrowiak

    2004-09-28

    We report the and/or state of several subprojects of our DOE sponsored research on Electronic and Nuclear Factors in Electron and Excitation Transfer: (1) Construction of an ultrafast Ti:sapphire amplifier. (2) Mediation of electronic interactions in host-guest molecules. (3) Theoretical models of electrolytes in weakly polar media. (4) Symmetry effects in intramolecular excitation transfer.

  11. Synthesis of a Precursor to Sacubitril Using Enabling Technologies.

    PubMed

    Lau, Shing-Hing; Bourne, Samuel L; Martin, Benjamin; Schenkel, Berthold; Penn, Gerhard; Ley, Steven V

    2015-11-01

    An efficient preparation of a precursor to the neprilysin inhibitor sacubitril is described. The convergent synthesis features a diastereoselective Reformatsky-type carbethoxyallylation and a rhodium-catalyzed stereoselective hydrogenation for installation of the two key stereocenters. Moreover, by integrating machine-assisted methods with batch processes, this procedure allows a safe and rapid production of the key intermediates which are promptly transformed to the target molecule (3·HCl) over 7 steps in 54% overall yield. PMID:26509957

  12. First hyperpolarizabilities of dipolar, bis-dipolar, and octupolar molecules

    NASA Astrophysics Data System (ADS)

    Yang, Si Kyung; Ahn, Hyun Cheol; Jeon, Seung-Joon; Asselberghs, Inge; Clays, Koen; Persoons, André; Cho, Bong Rae

    2005-02-01

    A series of dipolar ( 1), bis-dipolar ( 2), and octupolar molecules ( 3) containing 1, 2, and 6 dipolar units within a molecule has been synthesized and their hyperpolarizabilities were analyzed. The βHRS increases in the order, 1 < 2 < 3. The 'monomeric' βzzz increases by approximately twofold from 1 to 2, whereas βzzz of 2 and βxxx of 3 are similar. Noteworthy is the parallel increase in the hyperpolarizability tensor with the λmax.

  13. Mannosyl Glycodendritic Structure Inhibits DC-SIGN-Mediated Ebola Virus Infection in cis and in trans

    PubMed Central

    Lasala, Fátima; Arce, Eva; Otero, Joaquín R.; Rojo, Javier; Delgado, Rafael

    2003-01-01

    We have designed a glycodendritic structure, BH30sucMan, that blocks the interaction between dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) and Ebola virus (EBOV) envelope. BH30sucMan inhibits DC-SIGN-mediated EBOV infection at nanomolar concentrations. BH30sucMan may counteract important steps of the infective process of EBOV and, potentially, of microorganisms shown to exploit DC-SIGN for cell entry and infection. PMID:14638512

  14. Discovery of 3-(trifluoromethyl)-1H-pyrazole-5-carboxamide activators of the M2 isoform of pyruvate kinase (PKM2).

    PubMed

    Xu, Yong; Liu, Xiao-Hui; Saunders, Michael; Pearce, Scott; Foulks, Jason M; Parnell, K Mark; Clifford, Adrianne; Nix, Rebecca N; Bullough, Jeremy; Hendrickson, Thomas F; Wright, Kevin; McCullar, Michael V; Kanner, Steven B; Ho, Koc-Kan

    2014-01-15

    Activators of the pyruvate kinase M2 (PKM2) are currently attracting significant interest as potential anticancer therapies. They may achieve a novel antiproliferation response in cancer cells through modulation of the classic 'Warburg effect' characteristic of aberrant metabolism. In this Letter, we describe the optimization of a weakly active screening hit to a structurally novel series of small molecule 3-(trifluoromethyl)-1H-pyrazole-5-carboxamides as potent PKM2 activators. PMID:24374270

  15. Inhibitory Receptor Expression Depends More Dominantly on Differentiation and Activation than “Exhaustion” of Human CD8 T Cells

    PubMed Central

    Legat, Amandine; Speiser, Daniel E.; Pircher, Hanspeter; Zehn, Dietmar; Fuertes Marraco, Silvia A.

    2013-01-01

    Under conditions of chronic antigen stimulation, such as persistent viral infection and cancer, CD8 T cells may diminish effector function, which has been termed “exhaustion.” Expression of inhibitory Receptors (iRs) is often regarded as a hallmark of “exhaustion.” Here we studied the expression of eight different iRs by CD8 T cells of healthy humans, including CTLA-4, PD1, TIM3, LAG3, 2B4, BTLA, CD160, and KLRG1. We show that many iRs are expressed upon activation, and with progressive differentiation to effector cells, even in absence of long-term (“chronic”) antigenic stimulation. In particular, we evaluated the direct relationship between iR expression and functionality in CD8 T cells by using anti-CD3 and anti-CD28 stimulation to stimulate all cells and differentiation subsets. We observed a striking up-regulation of certain iRs following the cytokine production wave, in agreement with the notion that iRs function as a negative feedback mechanism. Intriguingly, we found no major impairment of cytokine production in cells positive for a broad array of iRs, as previously shown for PD1 in healthy donors. Rather, the expression of the various iRs strongly correlated with T cell differentiation or activation states, or both. Furthermore, we analyzed CD8 T cells from lymph nodes (LNs) of melanoma patients. Interestingly, we found altered iR expression and lower cytokine production by T cells from metastatic LNs, but also from non-metastatic LNs, likely due to mechanisms which are not related to exhaustion. Together, our data shows that expression of iRs per se does not mark dysfunctional cells, but is rather tightly linked to activation and differentiation. This study highlights the importance of considering the status of activation and differentiation for the study and the clinical monitoring of CD8 T cells. PMID:24391639

  16. Modulation of Innate Immune Mechanisms to Enhance Leishmania Vaccine-Induced Immunity: Role of Coinhibitory Molecules.

    PubMed

    Gannavaram, Sreenivas; Bhattacharya, Parna; Ismail, Nevien; Kaul, Amit; Singh, Rakesh; Nakhasi, Hira L

    2016-01-01

    No licensed human vaccines are currently available against any parasitic disease including leishmaniasis. Several antileishmanial vaccine formulations have been tested in various animal models, including genetically modified live-attenuated parasite vaccines. Experimental infection studies have shown that Leishmania parasites utilize a broad range of strategies to undermine effector properties of host phagocytic cells, i.e., dendritic cells (DCs) and macrophages (MΦ). Furthermore, Leishmania parasites have evolved strategies to actively inhibit TH1 polarizing functions of DCs and to condition the infected MΦ toward anti-inflammatory/alternative/M2 phenotype. The altered phenotype of phagocytic cells is characterized by decreased production of antimicrobial reactive oxygen, nitrogen molecules, and pro-inflammatory cytokines, such as IFN-γ, IL-12, and TNF-α. These early events limit the activation of TH1-effector cells and set the stage for pathogenesis. Furthermore, this early control of innate immunity by the virulent parasites results in substantial alteration in the adaptive immunity characterized by reduced proliferation of CD4(+) and CD8(+) T cells and TH2-biased immunity that results in production of anti-inflammatory cytokines, such as TGF-β, and IL-10. More recent studies have also documented the induction of coinhibitory ligands, such as CTLA-4, PD-L1, CD200, and Tim-3, that induce exhaustion and/or non-proliferation in antigen-experienced T cells. Most of these studies focus on viral infections in chronic phase, thus limiting the direct application of these results to parasitic infections and much less to parasitic vaccines. However, these studies suggest that vaccine-induced protective immunity can be modulated using strategies that enhance the costimulation that might reduce the threshold necessary for T cell activation and conversely by strategies that reduce or block inhibitory molecules, such as PD-L1 and CD200. In this review, we will focus on

  17. MART-1 peptide vaccination plus IMP321 (LAG-3Ig fusion protein) in patients receiving autologous PBMCs after lymphodepletion: results of a Phase I trial

    PubMed Central

    2014-01-01

    Background Immunotherapy offers a promising novel approach for the treatment of cancer and both adoptive T-cell transfer and immune modulation lead to regression of advanced melanoma. However, the potential synergy between these two strategies remains unclear. Methods We investigated in 12 patients with advanced stage IV melanoma the effect of multiple MART-1 analog peptide vaccinations with (n = 6) or without (n = 6) IMP321 (LAG-3Ig fusion protein) as an adjuvant in combination with lymphodepleting chemotherapy and adoptive transfer of autologous PBMCs at day (D) 0 (Trial registration No: NCT00324623). All patients were selected on the basis of ex vivo detectable MART-1-specific CD8 T-cell responses and immunized at D0, 8, 15, 22, 28, 52, and 74 post-reinfusion. Results After immunization, a significant expansion of MART-1-specific CD8 T cells was measured in 83% (n = 5/6) and 17% (n = 1/6) of patients from the IMP321 and control groups, respectively (P < 0.02). Compared to the control group, the mean fold increase of MART-1-specific CD8 T cells in the IMP321 group was respectively >2-, >4- and >6-fold higher at D15, D30 and D60 (P < 0.02). Long-lasting MART-1-specific CD8 T-cell responses were significantly associated with IMP321 (P < 0.02). At the peak of the response, MART-1-specific CD8 T cells contained higher proportions of effector (CCR7− CD45RA+/−) cells in the IMP321 group (P < 0.02) and showed no sign of exhaustion (i.e. were mostly PD1−CD160−TIM3−LAG3−2B4+/−). Moreover, IMP321 was associated with a significantly reduced expansion of regulatory T cells (P < 0.04); consistently, we observed a negative correlation between the relative expansion of MART-1-specific CD8 T cells and of regulatory T cells. Finally, although there were no confirmed responses as per RECIST criteria, a transient, 30-day partial response was observed in a patient from the IMP321 group. Conclusions Vaccination with IMP321 as an

  18. Mean Upper-Ocean Circulation of the Southern Hemisphere Oceans Based on Goce Data

    NASA Astrophysics Data System (ADS)

    Menezes, V. V.; Bingham, R. J.; Vianna, M. L.; Phillips, H. E.

    2012-12-01

    One of the main goals of the Gravity and steady-state Ocean Circulation Explorer (GOCE) satellite mission launched in 2009 is to improve the previous estimates of the global ocean circulation structures determined from Mean Dynamic Topographies (MDTs). Recently published studies suggest that the GOCE-based MDTs and their respective mean geostrophic circulation fields (MGCs) are superior to those obtained from GRACE (Gravity Recovery and Climate Experiment)-only data. These studies focus mostly on the circulation of the North Atlantic and North Pacific oceans with emphasis on the strong western boundary current systems. In contrast, no detailed assessment has yet been made to determine the impact of the GOCE models in the southern hemisphere (SH) upper-ocean circulation especially in the subtropical region. It is generally recognized that the SH circulation is still not well established even at large scales, and the new GOCE and GRACE products can contribute to increase our understanding of the dominant currents in these regions, which may have even greater impact on the global climate than the NH counterparts. In the present work, we compute five global GOCE-derived MDTs with a 0.25 x 0.25 degree spatial grid based on three GOCE geoid models (TIM3, GOCO02S, GOCO3S) and three mean sea surfaces (CLS01, CLS11, DTU10) using the standard spectral approach (MSS minus Geoid). These MDTs do not have the well-known large-amplitude striation-type noise that plagued all of the GRACE-only MDTs with he same resolution, but still present commission errors which are filptered out with Singular Spectrum Analysis methods. Additionally, the MGCs were calculated by use of a Anderssen-Hegland averaging scheme for estimation of derivatives, which is able to filter out the well-known high amplitude noise caused by standard finite-difference methods. Comparisons with previous GRACE-only MGCs show that GOCE permits retrieval of currents with much higher intensities (e.g. the Agulhas

  19. Modulation of Innate Immune Mechanisms to Enhance Leishmania Vaccine-Induced Immunity: Role of Coinhibitory Molecules

    PubMed Central

    Gannavaram, Sreenivas; Bhattacharya, Parna; Ismail, Nevien; Kaul, Amit; Singh, Rakesh; Nakhasi, Hira L.

    2016-01-01

    No licensed human vaccines are currently available against any parasitic disease including leishmaniasis. Several antileishmanial vaccine formulations have been tested in various animal models, including genetically modified live-attenuated parasite vaccines. Experimental infection studies have shown that Leishmania parasites utilize a broad range of strategies to undermine effector properties of host phagocytic cells, i.e., dendritic cells (DCs) and macrophages (MΦ). Furthermore, Leishmania parasites have evolved strategies to actively inhibit TH1 polarizing functions of DCs and to condition the infected MΦ toward anti-inflammatory/alternative/M2 phenotype. The altered phenotype of phagocytic cells is characterized by decreased production of antimicrobial reactive oxygen, nitrogen molecules, and pro-inflammatory cytokines, such as IFN-γ, IL-12, and TNF-α. These early events limit the activation of TH1-effector cells and set the stage for pathogenesis. Furthermore, this early control of innate immunity by the virulent parasites results in substantial alteration in the adaptive immunity characterized by reduced proliferation of CD4+ and CD8+ T cells and TH2-biased immunity that results in production of anti-inflammatory cytokines, such as TGF-β, and IL-10. More recent studies have also documented the induction of coinhibitory ligands, such as CTLA-4, PD-L1, CD200, and Tim-3, that induce exhaustion and/or non-proliferation in antigen-experienced T cells. Most of these studies focus on viral infections in chronic phase, thus limiting the direct application of these results to parasitic infections and much less to parasitic vaccines. However, these studies suggest that vaccine-induced protective immunity can be modulated using strategies that enhance the costimulation that might reduce the threshold necessary for T cell activation and conversely by strategies that reduce or block inhibitory molecules, such as PD-L1 and CD200. In this review, we will focus on the

  20. Electronic and Transport Properties of Quasi-1D Wires of Biological Molecules

    NASA Astrophysics Data System (ADS)

    Oetzel, Björn; Matthes, Lars; Tandetzky, Falk; Ortmann, Frank; Bechstedt, Friedhelm; Hannewald, Karsten

    2010-03-01

    In the search for organic materials with good charge-transport properties, artificial stacks of biological molecules are considered attractive candidates [1,2]. In this spirit, we present ab-initio DFT calculations of the structural, electronic, and quantum-transport properties of quasi-1D wires based on guanine and eumelanin molecules [3]. Hereby, a special focus is put on the results for the electronic bandwidths and the consequences for potential applications. [4pt] [1] R. di Felice et al., Phys. Rev. B 65, 045104 (2001) [0pt] [2] P. Meredith et al., Pigment Cell Res. 19, 572 (2006) [0pt] [3] B. Oetzel et al. (unpublished)

  1. Life Sciences Issues for a Mission to Mars

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Session MP5 includes short reports on: (1) Cardiovascular Concerns for a Mars Mission: Autonomic and Biomechanical Effects; (2) Reducing the Risk of Space Radiation Induced Bioeffects: Vehicle Design and Protectant Molecules; (3) Musculoskeletal Issues for Long Duration Mission: Muscle Mass Preservation, Renal Stone Risk Factors, Countermeasures, and Contingency Treatment Planning; (4) Psychological Issues and Crew Selection for a Mars Mission: Maximizing the Mix for the Long Haul; and (5) Issues in Crew Health, Medical Selection and Medical Officer (CMO) Training for a Mission to Mars.

  2. Computational chemistry and aeroassisted orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    Cooper, D. M.; Jaffe, R. L.; Arnold, J. O.

    1985-01-01

    An analysis of the radiative heating phenomena encountered during a typical aeroassisted orbital transfer vehicle (AOTV) trajectory was made to determine the potential impact of computational chemistry on AOTV design technology. Both equilibrium and nonequilibrium radiation mechanisms were considered. This analysis showed that computational chemistry can be used to predict (1) radiative intensity factors and spectroscopic data; (2) the excitation rates of both atoms and molecules; (3) high-temperature reaction rate constants for metathesis and charge exchange reactions; (4) particle ionization and neutralization rates and cross sections; and (5) spectral line widths.

  3. A Ferrocene-Quinoxaline Derivative as a Highly Selective Probe for Colorimetric and Redox Sensing of Toxic Mercury(II) Cations

    PubMed Central

    Zapata, Fabiola; Caballero, Antonio; Molina, Pedro; Tarraga, Alberto

    2010-01-01

    A new chemosensor molecule 3 based on a ferrocene-quinoxaline dyad recognizes mercury (II) cations in acetonitrile solution. Upon recognition, an anodic shift of the ferrocene/ferrocenium oxidation peaks and a progressive red-shift (Δλ = 140 nm) of the low-energy band, are observed in its absorption spectrum. This change in the absorption spectrum is accompanied by a colour change from orange to deep green, which can be used for a “naked-eye” detection of this metal cation. PMID:22163528

  4. Applications of Group Theory to Atoms, Molecules, and Solids

    NASA Astrophysics Data System (ADS)

    Wolfram, Thomas; Ellialtıǧlu, Şinasi

    2014-01-01

    Preface; 1. Introductory example: squarene; 2. Molecular vibrations of isotopically substituted AB2 molecules; 3. Spherical symmetry and the full rotation group; 4. Crystal field theory; 5. Electron spin and angular momentum; 6. Molecular electronic structure: the LCAO model; 7. Electronic states of diatomic molecules; 8. Transition metal complexes; 9. Space groups and crystalline solids; 10. Application of space group theory: energy bands for the perovskite structure; 11. Applications of space group theory: lattice vibrations; 12. Time reversal and magnetic groups; 13. Graphene; 14. Carbon nanotubes; Appendixes; Index.

  5. Highly-Immunogenic Virally-Vectored T-cell Vaccines Cannot Overcome Subversion of the T-cell Response by HCV during Chronic Infection.

    PubMed

    Swadling, Leo; Halliday, John; Kelly, Christabel; Brown, Anthony; Capone, Stefania; Ansari, M Azim; Bonsall, David; Richardson, Rachel; Hartnell, Felicity; Collier, Jane; Ammendola, Virginia; Del Sorbo, Mariarosaria; Von Delft, Annette; Traboni, Cinzia; Hill, Adrian V S; Colloca, Stefano; Nicosia, Alfredo; Cortese, Riccardo; Klenerman, Paul; Folgori, Antonella; Barnes, Eleanor

    2016-01-01

    An effective therapeutic vaccine for the treatment of chronic hepatitis C virus (HCV) infection, as an adjunct to newly developed directly-acting antivirals (DAA), or for the prevention of reinfection, would significantly reduce the global burden of disease associated with chronic HCV infection. A recombinant chimpanzee adenoviral (ChAd3) vector and a modified vaccinia Ankara (MVA), encoding the non-structural proteins of HCV (NSmut), used in a heterologous prime/boost regimen induced multi-specific, high-magnitude, durable HCV-specific CD4+ and CD8+ T-cell responses in healthy volunteers, and was more immunogenic than a heterologous Ad regimen. We now assess the immunogenicity of this vaccine regimen in HCV infected patients (including patients with a low viral load suppressed with interferon/ribavirin therapy), determine T-cell cross-reactivity to endogenous virus, and compare immunogenicity with that observed previously in both healthy volunteers and in HCV infected patients vaccinated with the heterologous Ad regimen. Vaccination of HCV infected patients with ChAd3-NSmut/MVA-NSmut was well tolerated. Vaccine-induced HCV-specific T-cell responses were detected in 8/12 patients; however, CD4+ T-cell responses were rarely detected, and the overall magnitude of HCV-specific T-cell responses was markedly reduced when compared to vaccinated healthy volunteers. Furthermore, HCV-specific cells had a distinct partially-functional phenotype (lower expression of activation markers, granzyme B, and TNFα production, weaker in vitro proliferation, and higher Tim3 expression, with comparable Tbet and Eomes expression) compared to healthy volunteers. Robust anti-vector T-cells and antibodies were induced, showing that there is no global defect in immunity. The level of viremia at the time of vaccination did not correlate with the magnitude of the vaccine-induced T-cell response. Full-length, next-generation sequencing of the circulating virus demonstrated that T-cells were

  6. Future perspectives in melanoma research: meeting report from the "Melanoma Bridge": Napoli, December 3rd-6th 2014.

    PubMed

    Ascierto, Paolo A; Atkins, Michael; Bifulco, Carlo; Botti, Gerardo; Cochran, Alistair; Davies, Michael; Demaria, Sandra; Dummer, Reinhard; Ferrone, Soldano; Formenti, Silvia; Gajewski, Thomas F; Garbe, Claus; Khleif, Samir; Kiessling, Rolf; Lo, Roger; Lorigan, Paul; Arthur, Grant Mc; Masucci, Giuseppe; Melero, Ignacio; Mihm, Martin; Palmieri, Giuseppe; Parmiani, Giorgio; Puzanov, Igor; Romero, Pedro; Schilling, Bastian; Seliger, Barbara; Stroncek, David; Taube, Janis; Tomei, Sara; Zarour, Hassane M; Testori, Alessandro; Wang, Ena; Galon, Jérôme; Ciliberto, Gennaro; Mozzillo, Nicola; Marincola, Francesco M; Thurin, Magdalena

    2015-01-01

    survival rates have also been observed with immune-targeted therapy for patients with metastatic melanoma. Immune-modulating antibodies came to the forefront with anti-CTLA-4, programmed cell death-1 (PD-1) and PD-1 ligand 1 (PD-L1) pathway blocking antibodies that result in durable responses in a subset of melanoma patients. Agents targeting other immune inhibitory (e.g., Tim-3) or immune stimulating (e.g., CD137) receptors and other approaches such as adoptive cell transfer demonstrate clinical benefit in patients with melanoma as well. These agents are being studied in combination with targeted therapies in attempt to produce longer-term responses than those more typically seen with targeted therapy. Other combinations with cytotoxic chemotherapy and inhibitors of angiogenesis are changing the evolving landscape of therapeutic options and are being evaluated to prevent or delay resistance and to further improve survival rates for this patient population. This meeting's specific focus was on advances in combination of targeted therapy and immunotherapy. Both combination targeted therapy approaches and different immunotherapies were discussed. Similarly to the previous meetings, the importance of biomarkers for clinical application as markers for diagnosis, prognosis and prediction of treatment response was an integral part of the meeting. The overall emphasis on biomarkers supports novel concepts toward integrating biomarkers into contemporary clinical management of patients with melanoma across the entire spectrum of disease stage. Translation of the knowledge gained from the biology of tumor microenvironment across different tumors represents a bridge to impact on prognosis and response to therapy in melanoma. PMID:26619946

  7. In Silico Molecular Docking and In Vitro Antidiabetic Studies of Dihydropyrimido[4,5-a]acridin-2-amines

    PubMed Central

    Bharathi, A.; Roopan, Selvaraj Mohana; Vasavi, C. S.; Munusami, Punnagai; Gayathri, G. A.; Gayathri, M.

    2014-01-01

    An in vitro antidiabetic activity on α-amylase and α–glucosidase activity of novel 10-chloro-4-(2-chlorophenyl)-12-phenyl-5,6-dihydropyrimido[4,5-a]acridin-2-amines (3a–3f) were evaluated. Structures of the synthesized molecules were studied by FT-IR, 1H NMR, 13C NMR, EI-MS, and single crystal X-ray structural analysis data. An in silico molecular docking was performed on synthesized molecules (3a–3f). Overall studies indicate that compound 3e is a promising compound leading to the development of selective inhibition of α-amylase and α-glucosidase. PMID:24991576

  8. Binding of terbium complex to polymerizable hybrid materials constructed from molecular assembly and its optical properties

    SciTech Connect

    Zhao Limin; Shao Xin; Yin Yibin; Li Wenzhi

    2009-06-03

    A new molecular precursor was synthesized by means of the amidation reaction of N-Phenylanthranilic acid with a cross-linking molecule (3-aminopropyl) trimethoxysilane, and characterized by nuclear magnetic resonance and infrared spectroscopy. Then, a chemically bonded rare-earth/inorganic polymeric hybrid material was constructed using the precursor as a bridge molecule that can both coordinate to rare-earth ions and form a Si-O network with tetraethoxysilane or polyvinyl alcohol after cohydrolysis and copolycondensation processes. Ultraviolet absorption and fluorescence spectra were applied to characterize the photophysical properties of the obtained hybrid material. The strong luminescence of Tb{sup 3+} substantiates optimum energy couple and effective intramolecular energy transfer between the triplet state energy of modified ligand bridge and emissive energy level of Tb{sup 3+}.

  9. New insights into the fragility dilemma in liquids

    NASA Astrophysics Data System (ADS)

    Huang, Dinghai; McKenna, Gregory B.

    2001-04-01

    A compilation of data for small molecule organic, polymeric, and inorganic glass-forming liquids shows that the original expectation, that there be a positive correlation between the thermodynamic measure of fragility Cpl/Cpg (or Cpl/Cpc) and the dynamic fragility index m, is not generally true. The results are consistent with three classes of behavior: (1) a decrease in m with increasing Cpl/Cpg for the polymeric glass formers; (2) a nearly constant value of m independent of Cpl/Cpc for small molecule organics and hydrogen bonding small molecules; (3) an increasing value of m with increasing Cpl/Cpc for inorganic glass formers as originally considered by Angell.

  10. New Insights into the Fragility Dilemma in Glass Forming Liquids

    NASA Astrophysics Data System (ADS)

    McKenna, Gregory B.; Huang, Dinghai

    2001-03-01

    A compilation of data for small molecule organic, polymeric and inorganic glass forming liquids shows that the original expectation, that there be a positive correlation between the thermodynamic measure of fragility (the heat capacity ratio between the liquid and the crystal) and the dynamic fragility index m, is not generally true. The results are consistent with three classes of behavior: 1) a decrease in m with increasing heat capacity ratio for the polymeric glass formers; 2)a nearly constant value of m independent of the heat capacity ratio for small molecule organics and hydrogen bonding small molecules; 3) an increasing value of m with increasing heat capacity ratio for inorganic glass formers as originally considered by Angell. The results suggest the possibility that "universality" of "glassiness" may not be true. We suggest the existence of "free volume" glass formers and "entropy" glass formers as separate classes of glass formers.

  11. A new alligator-clip compound for molecular electronics

    NASA Astrophysics Data System (ADS)

    Jacob, Timo; Blanco, Mario; Goddard, William A.

    2004-06-01

    We used the B3LYP flavor of density functional calculations to study new alligator-clip compounds for molecular electronics with platinum electrodes. First, with commonly used S-based linkage molecule 3-methyl-1,2-dithiolane (MDTL) we find that after chemisorption on Pt(1 1 1) the most stable structure is ring-opened with a binding energy of 32.44 kcal/mol. Among several alternative alligator-clip compounds we find that P-based molecules lead to much higher binding energies. For the ring-closed structure of 3-methyl-1,2-diphospholane (MDPL) a binding energy of 47.72 kcal/mol was calculated and even 54.88 kcal/mol for the ring-opened molecule. Thus, MDPL provides a more stable link to the metal surface and might increase the conductance.

  12. Proton and charge transfer reactions dynamics of a hydroxyflavone derivative in a polar solvent and in a cyclodextrin nanocavity

    NASA Astrophysics Data System (ADS)

    Sanz, M.; Organero, J. A.; Douhal, A.

    2007-09-01

    In this work, we report on the observation of ultrafast intramolecular charge- and proton-transfer reactions of 4'-dimethylaminoflavonol (DMAF) in N, N-dimethyl formamide and in γ-cyclodextrin (γ-CD) solution. Upon femtosecond excitation an intramolecular charge transfer (ICT) reaction takes place to produce an ICT structure in ˜200 fs. This structure may undergo a proton transfer reaction to generate a zwitterionic (Z) form in 2-3 ps, or relaxes in its potential energy well, to later equilibrate with that of Z in hundreds of ps. Addition of γ-CD does not significantly affect the fast dynamics of the formed anion. The fs-emission signals of the parent molecule, 3-hydroxyflavone, indicate that the dimethyl amino group in DMAF enhances the rate constant of intermolecular proton-transfer and intramolecular charge-transfer reactions.

  13. Photochemically-induced fluorescence dosage of non-fluorescent pyrethroid (Etofenprox) in natural water using a cationic micellar medium.

    PubMed

    Adamou, Rabani; Coly, Atanasse; Abdoulaye, Alassane; Soumaila, Maimouna; Moussa, Idrissa; Ikhiri, Khalid; Tine, Alphonse

    2011-07-01

    An analytical method based on the use of UV-irradiation to produce fluorescent derivatives from Etofenprox a non-fluorescent pyrethroid insecticide is described. The impact of cetyltrimethylammonium chloride (CTAC) micellar medium on the Etofenprox photochemically-induced fluorescence (PIF) is reported. Parameters influencing the sensitivity and repeatability of the PIF method have been optimized. The alkaline medium (NaOH 6 × 10(-2) M) + CTAC surfactant molecules (3.84 mg/ml) in acetonitrile is found to be very suitable for this pyrethroid insecticide analysis in environment matrices. Linear dynamic range is established over more than two orders of magnitude. The limit of detection is lower than 5 ng/ml. The method seems to be suitable for environmental matrices quality control. Application to the analysis of spiked natural waters gave recoveries rate ranged from 94 to 104% and 107 to 115% respectively for river and pound water. PMID:21222143

  14. Unexpected interplay of bonding height and energy level alignment at heteromolecular hybrid interfaces.

    PubMed

    Stadtmüller, Benjamin; Lüftner, Daniel; Willenbockel, Martin; Reinisch, Eva M; Sueyoshi, Tomoki; Koller, Georg; Soubatch, Serguei; Ramsey, Michael G; Puschnig, Peter; Tautz, F Stefan; Kumpf, Christian

    2014-01-01

    Although geometric and electronic properties of any physical or chemical system are always mutually coupled by the rules of quantum mechanics, counterintuitive coincidences between the two are sometimes observed. The coadsorption of the organic molecules 3,4,9,10-perylene tetracarboxylic dianhydride and copper-II-phthalocyanine on Ag(111) represents such a case, since geometric and electronic structures appear to be decoupled: one molecule moves away from the substrate while its electronic structure indicates a stronger chemical interaction, and vice versa for the other. Our comprehensive experimental and ab-initio theoretical study reveals that, mediated by the metal surface, both species mutually amplify their charge-donating and -accepting characters, respectively. This resolves the apparent paradox, and demonstrates with exceptional clarity how geometric and electronic bonding parameters are intertwined at metal-organic interfaces. PMID:24739211

  15. Infrared spectroscopy of molecules with nanorod arrays: a numerical study.

    PubMed

    Tardieu, Clément; Vincent, Grégory; Haïdar, Riad; Collin, Stéphane

    2016-04-15

    Nanorod arrays with diameters much smaller than the wavelength exhibit sharp resonances with strong electric-field enhancement and angular dependence. They are investigated for enhanced infrared spectroscopy of molecular bonds. The molecule 3-cyanopropyldimethylchlorosilane (CS) is taken as a reference, and its complex permittivity is determined experimentally in the 3-5 μm wavelength range. When grafted on silicon nitride nanorods, we show numerically that its weak absorption bands due to chemical bond vibrations can be enhanced by several orders of magnitude compared with unstructured thin film. We propose a figure of merit (FoM) to assess the performance of this spectroscopic scheme, and we study the impact of the nanorod cross section on the FoM. PMID:27082334

  16. Identification of Cell Surface Molecules Involved in Dystroglycan-Independent Lassa Virus Cell Entry

    PubMed Central

    Ströher, Ute; Ebihara, Hideki; Feldmann, Heinz

    2012-01-01

    Although O-mannosylated dystroglycan is a receptor for Lassa virus, a causative agent of Lassa fever, recent findings suggest the existence of an alternative receptor(s). Here we identified four molecules as receptors for Lassa virus: Axl and Tyro3, from the TAM family, and dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN) and liver and lymph node sinusoidal endothelial calcium-dependent lectin (LSECtin), from the C-type lectin family. These molecules enhanced the binding of Lassa virus to cells and mediated infection independently of dystroglycan. Axl- or Tyro3-mediated infection required intracellular signaling via the tyrosine kinase activity of Axl or Tyro3, whereas DC-SIGN- or LSECtin-mediated infection and binding were dependent on a specific carbohydrate and on ions. The identification of these four molecules as Lassa virus receptors advances our understanding of Lassa virus cell entry. PMID:22156524

  17. Construction of hybrid material with double chemical bond from functional bridge ligand: Molecular modification, lotus root-like micromorphology and strong luminescence

    NASA Astrophysics Data System (ADS)

    Yan, Bing; Sui, Yu-Long

    2006-07-01

    Modifying benzoic acid with a cross-linking molecule (3-aminopropyl)triethoxysilane (abbreviated as APES), a fictional molecular bridge with double reactivity was achieved by the amidation reaction between them. Then the modified functional molecule, which behaving as a bridge, both coordinate with terbium ion through amide's oxygen atom and form the Si-O chemical bond in an in situ sol-gel process with matrix precursor (tetraethoxysilane, TEOS). As a result, a novel molecular hybrid material (Tb-BA-APES) with double chemical bond (Tb-O coordination bond and Si-O covalent bond) was constructed. The strong luminescence of Tb 3+ substantiates optimum energy couple and effective intramolecular energy transfer between the triplet state energy of modified ligand bridge and emissive energy level of Tb 3+. Especially SEM of the molecular hybrid material exhibits unexpected microlotus root-like pore morphology.

  18. Unexpected interplay of bonding height and energy level alignment at heteromolecular hybrid interfaces

    NASA Astrophysics Data System (ADS)

    Stadtmüller, Benjamin; Lüftner, Daniel; Willenbockel, Martin; Reinisch, Eva M.; Sueyoshi, Tomoki; Koller, Georg; Soubatch, Serguei; Ramsey, Michael G.; Puschnig, Peter; Tautz, F. Stefan; Kumpf, Christian

    2014-04-01

    Although geometric and electronic properties of any physical or chemical system are always mutually coupled by the rules of quantum mechanics, counterintuitive coincidences between the two are sometimes observed. The coadsorption of the organic molecules 3,4,9,10-perylene tetracarboxylic dianhydride and copper-II-phthalocyanine on Ag(111) represents such a case, since geometric and electronic structures appear to be decoupled: one molecule moves away from the substrate while its electronic structure indicates a stronger chemical interaction, and vice versa for the other. Our comprehensive experimental and ab-initio theoretical study reveals that, mediated by the metal surface, both species mutually amplify their charge-donating and -accepting characters, respectively. This resolves the apparent paradox, and demonstrates with exceptional clarity how geometric and electronic bonding parameters are intertwined at metal-organic interfaces.

  19. Specific recognition of supercoiled plasmid DNA by affinity chromatography using a synthetic aromatic ligand.

    PubMed

    Caramelo-Nunes, Catarina; Tomaz, Cândida T

    2015-01-01

    Liquid chromatography is the method of choice for the purification of plasmid DNA (pDNA), since it is simple, robust, versatile, and highly reproducible. The most important features of a chromatographic procedure are the use of suitable stationary phases and ligands. As conventional purification protocols are being replaced by more sophisticated and selective procedures, the focus changes toward designing and selecting ligands of high affinity and specificity. In fact, the chemical composition of the chromatographic supports determines the interactions established with the target molecules, allowing their preferential retention over the undesirable ones. Here it is described the selective recognition and purification of supercoiled pDNA by affinity chromatography, using an intercalative molecule (3,8-diamino-6-phenylphenanthridine) as ligand. PMID:25749945

  20. Computational investigations of HNO in biology

    PubMed Central

    Zhang, Yong

    2013-01-01

    HNO (nitroxyl) has been found to have many physiological effects in numerous biological processes. Computational investigations have been employed to help understand the structural properties of HNO complexes and HNO reactivities in some interesting biologically relevant systems. The following computational aspects were reviewed in this work: 1) structural and energetic properties of HNO isomers; 2) interactions between HNO and non-metal molecules; 3) structural and spectroscopic properties of HNO metal complexes; 4) HNO reactions with biologically important non-metal systems; 5) involvement of HNO in reactions of metal complexes and metalloproteins. Results indicate that computational investigations are very helpful to elucidate interesting experimental phenomena and provide new insights into unique structural, spectroscopic, and mechanistic properties of HNO involvement in biology. PMID:23103077

  1. The Fe(III) and Ga(III) coordination chemistry of 3-(1-hydroxymethylidene) and 3-(1-hydroxydecylidene)-5-(2-hydroxyethyl)pyrrolidine-2,4-dione: Novel tetramic acid degradation products of homoserine lactone bacterial quorum sensing molecules

    PubMed Central

    Romano, Ariel A.; Hahn, Tobias; Davis, Nicole; Lowery, Colin A.; Struss, Anjali K.; Janda, Kim D.; Böttger, Lars H.; Matzanke, Berthold F.; Carrano, Carl J.

    2011-01-01

    Bacteria use small diffusible molecules to exchange information in a process called quorum sensing (QS). An important class of quorum sensing molecules used by Gram-negative bacteria is the family of N-acylhomoserine lactones (HSL). It was recently discovered that a degradation product of the QS molecule 3-oxo-C12-homoserine lactone, the tetramic acid 3-(1-hydroxydecylidene)-5-(2-hydroxyethyl)pyrrolidine-2,4-dione, is a potent antibacterial agent, thus implying roles for QS outside of simply communication. Because these tetramic acids also appear to bind iron with appreciable affinity it was suggested that metal binding might contribute to their biological activity. Here, using a variety of spectroscopic tools, we describe the coordination chemistry of both the methylidene and decylidene tetramic acid derivatives with Fe(III) and Ga(III) and discuss the potential biological significance of such metal binding. PMID:22178671

  2. The role of human dendritic cells in HIV-1 infection.

    PubMed

    Ahmed, Zahra; Kawamura, Tatsuyoshi; Shimada, Shinji; Piguet, Vincent

    2015-05-01

    Dendritic cells (DCs) and their subsets have multifaceted roles in the early stages of HIV-1 transmission and infection. DC studies have led to remarkable discoveries, including identification of restriction factors, cellular structures promoting viral transmission including the infectious synapse or the interplay of the C-type lectins, Langerin on Langerhans cells (LCs), and dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin on other DC subsets, limiting or facilitating HIV transmission to CD4(+) T cells, respectively. LCs/DCs are also exposed to encountering HIV-1 and other sexually transmitted infections (herpes simplex virus-2, bacteria, fungi), which reprogram HIV-1 interaction with these cells. This review will summarize advances in the role of DCs during HIV-1 infection and discuss their potential involvement in the development of preventive strategies against HIV-1 and other sexually transmitted infections. PMID:25407434

  3. Co-assembled thin films of Ag nanowires and functional nanoparticles at the liquid-liquid interface by shaking

    NASA Astrophysics Data System (ADS)

    Zhang, Shao-Yi; Liu, Jian-Wei; Zhang, Chuan-Ling; Yu, Shu-Hong

    2013-05-01

    In this paper, we report the fabrication of co-assembled thin films composed of silver nanowires (NWs) and Au nanoparticles (NPs) at the liquid-liquid interface (water-chloroform) by vigorous shaking. The composition of co-assembled thin films can be controlled by adjusting the concentration of the nanosized building blocks. As a versatile interfacial assembly method, other nanoparticles such as Ag2S and Fe3O4 NPs can also be co-assembled with Ag NWs using the same procedure. Meanwhile, the co-assembly state of the obtained Au NPs and Ag NWs makes a significant contribution to the high sensitivity of surface-enhanced Raman scattering (SERS) to model the molecule 3,3'-diethylthiatricarbocyanine iodide (DTTCI). The SERS intensities show high dependence on the molar ratio of Au NPs and Ag NWs and the layer number of the co-assembled thin films. This shaking-assisted liquid-liquid assembly system has been proved to be a facile way for co-assembling nanowires and nanoparticles, and will pave a way for further applications of the macroscopic co-assemblies with novel functionalities.In this paper, we report the fabrication of co-assembled thin films composed of silver nanowires (NWs) and Au nanoparticles (NPs) at the liquid-liquid interface (water-chloroform) by vigorous shaking. The composition of co-assembled thin films can be controlled by adjusting the concentration of the nanosized building blocks. As a versatile interfacial assembly method, other nanoparticles such as Ag2S and Fe3O4 NPs can also be co-assembled with Ag NWs using the same procedure. Meanwhile, the co-assembly state of the obtained Au NPs and Ag NWs makes a significant contribution to the high sensitivity of surface-enhanced Raman scattering (SERS) to model the molecule 3,3'-diethylthiatricarbocyanine iodide (DTTCI). The SERS intensities show high dependence on the molar ratio of Au NPs and Ag NWs and the layer number of the co-assembled thin films. This shaking-assisted liquid-liquid assembly system

  4. Comprehensive Map of Molecules Implicated in Obesity.

    PubMed

    Jagannadham, Jaisri; Jaiswal, Hitesh Kumar; Agrawal, Stuti; Rawal, Kamal

    2016-01-01

    Obesity is a global epidemic affecting over 1.5 billion people and is one of the risk factors for several diseases such as type 2 diabetes mellitus and hypertension. We have constructed a comprehensive map of the molecules reported to be implicated in obesity. A deep curation strategy was complemented by a novel semi-automated text mining system in order to screen 1,000 full-length research articles and over 90,000 abstracts that are relevant to obesity. We obtain a scale free network of 804 nodes and 971 edges, composed of 510 proteins, 115 genes, 62 complexes, 23 RNA molecules, 83 simple molecules, 3 phenotype and 3 drugs in "bow-tie" architecture. We classify this network into 5 modules and identify new links between the recently discovered fat mass and obesity associated FTO gene with well studied examples such as insulin and leptin. We further built an automated docking pipeline to dock orlistat as well as other drugs against the 24,000 proteins in the human structural proteome to explain the therapeutics and side effects at a network level. Based upon our experiments, we propose that therapeutic effect comes through the binding of one drug with several molecules in target network, and the binding propensity is both statistically significant and different in comparison with any other part of human structural proteome. PMID:26886906

  5. Comprehensive Map of Molecules Implicated in Obesity

    PubMed Central

    Agrawal, Stuti

    2016-01-01

    Obesity is a global epidemic affecting over 1.5 billion people and is one of the risk factors for several diseases such as type 2 diabetes mellitus and hypertension. We have constructed a comprehensive map of the molecules reported to be implicated in obesity. A deep curation strategy was complemented by a novel semi-automated text mining system in order to screen 1,000 full-length research articles and over 90,000 abstracts that are relevant to obesity. We obtain a scale free network of 804 nodes and 971 edges, composed of 510 proteins, 115 genes, 62 complexes, 23 RNA molecules, 83 simple molecules, 3 phenotype and 3 drugs in “bow-tie” architecture. We classify this network into 5 modules and identify new links between the recently discovered fat mass and obesity associated FTO gene with well studied examples such as insulin and leptin. We further built an automated docking pipeline to dock orlistat as well as other drugs against the 24,000 proteins in the human structural proteome to explain the therapeutics and side effects at a network level. Based upon our experiments, we propose that therapeutic effect comes through the binding of one drug with several molecules in target network, and the binding propensity is both statistically significant and different in comparison with any other part of human structural proteome. PMID:26886906

  6. From structural biology to designing therapy for inborn errors of metabolism.

    PubMed

    Yue, Wyatt W

    2016-07-01

    At the SSIEM Symposium in Istanbul 2010, I presented an overview of protein structural approaches in the study of inborn errors of metabolism (Yue and Oppermann 2011). Five years on, the field is going strong with new protein structures, uncovered catalytic functions and novel chemical matters for metabolic enzymes, setting the stage for the next generation of drug discovery. This article aims to update on recent advances and lessons learnt on inborn errors of metabolism via the protein-centric approach, citing examples of work from my group, collaborators and co-workers that cover diverse pathways of transsulfuration, cobalamin and glycogen metabolism. Taking into consideration that many inborn errors of metabolism result in the loss of enzyme function, this presentation aims to outline three key principles that guide the design of small molecule therapy in this technically challenging field: (1) integrating structural, biochemical and cell-based data to evaluate the wide spectrum of mutation-driven enzyme defects in stability, catalysis and protein-protein interaction; (2) studying multi-domain proteins and multi-protein complexes as examples from nature, to learn how enzymes are activated by small molecules; (3) surveying different regions of the enzyme, away from its active site, that can be targeted for the design of allosteric activators and inhibitors. PMID:27240455

  7. A new window towards multidimensional sensing of transition metal cations through dual mode sensing ability of N-benzyl-(3-hydoxy-2-naphthalene): Emission enhancement coupled remarkable spectral shift

    NASA Astrophysics Data System (ADS)

    Paul, Bijan Kumar; Mahanta, Subrata; Singh, Rupashree Balia; Guchhait, Nikhil

    2011-06-01

    A structurally simple Schiff base N-benzyl-(3-hydroxy-2-naphthalene) (NBHN32) has been synthesized and characterized by 1H NMR, 13C NMR, and DEPT spectroscopy. The photophysical behaviour of NBHN32 in response to the presence of various transition metal cations has been explored by means of steady-state absorption, emission and time-resolved emission spectroscopy techniques. Efficient through space intramolecular photoinduced electron transfer (PET) between the naphthalene fluorophore and the imine group has been argued for extremely low fluorescence yield of NBHN32 compared to the parent molecule 3-hydroxy-2-naphthaldehyde (HN32) containing the same fluorophore but lacking the receptor moiety. Transition metal ion-induced emission enhancement is thus addressed on the lexicon of perturbation of the PET by the metal ions. Apart from fluorescence enhancement, transition metal ion imparts remarkable shift of the emission maxima of NBHN32, which is another unique aspect on the proposed ability of NBHN32 to function as a fluorescence chemosensor.

  8. A ratiometric fluorescence nanosensor for highly selective and sensitive detection of selenite.

    PubMed

    Chen, Linfeng; Tian, Xike; Zhao, Yuan; Li, Yong; Yang, Chao; Zhou, Zhaoxin; Liu, Xiangwen

    2016-08-01

    The instant and on-site detection of selenium still remains a challenge for environmental monitoring and medical prevention. We herein developed a ratiometric fluorescent nanosensor for accurate and on-site sensing of SeO3(2-) by linking the recognition molecule 3,3'-diaminobenzidine (DAB) onto the surface of carboxyl group modified CdTe@SiO2. The fluorescence of DAB on the surface of silica nanospheres could be selectively and efficiently enhanced by SeO3(2-) through a surface chelating reaction between DAB and SeO3(2-). Thus, in the presence of SeO3(2-), the nanosensor would show two characteristic fluorescence emissions of Se-DAB and CdTe QDs under a single excitation wavelength. The selectivity and the optimal conditions for the detection of SeO3(2-) were carefully investigated. The ratio of F530/F635 linearly increased with increasing SeO3(2-) concentration in the range of 0 to 2.5 μM and the detection limit reaches as low as 6.68 nM (0.53 ppb). This developed nanosensor has the capability of on-site detection in an aqueous system without any separation step. The Se concentrations in selenium-rich food were detected and the results were consistent with the values determined by ICP-AES. PMID:27241591

  9. Electronic Properties of Chlorine, Methyl, and Chloromethyl as Substituents to the Ethylene Group--Viewed from the Core of Carbon.

    PubMed

    Zahl, Maria G; Fossheim, Randi; Børve, Knut J; Sæthre, Leif J; Thomas, T Darrah

    2015-09-10

    "Substituent effects" is an important and useful concept in organic chemistry. Although there are many approaches to parametrizing the electronic and steric effects of substituents, the physical basis for the parameters is often unclear. The purpose of the present work is to explore the properties of chemical shifts in carbon 1s energies as a well-defined basis for characterizing substituents to an ethylene C═C moiety. To this end, high-resolution carbon 1s photoelectron spectra of six chloro-substituted ethenes and seven chloro-substituted propenes have been measured in the gas phase. Site-specific adiabatic ionization energies have been determined from the spectra using theoretical ab initio calculations to predict the vibrational structures. For two molecules, 3-chloropropene and 2,3-dichloropropene, the spectral analyses give quantitative results for the conformer populations. The observed shifts have been analyzed in terms of initial-state (potential) and relaxation effects, and charge relaxation has also been analyzed by means of natural resonance theory. On the basis of core-level spectroscopy and models, chlorine, methyl, and chloromethyl have been characterized in terms of their effect on the carbon to which they are attached (α site) as well as the neighboring sp(2) carbon (β site). The derived spectroscopic substituent parameters are characterized by both inductive (electronegativity) effects and the ability of each substituent to engage in electron delocalization via the π system. Moreover, the adopted approach is extended to include substituent-substituent interaction parameters. PMID:26280174

  10. Delineation of the Clinical, Molecular and Cellular Aspects of Novel JAM3 Mutations Underlying the Autosomal Recessive Hemorrhagic Destruction of the Brain, Subependymal Calcification and Congenital Cataracts

    PubMed Central

    Akawi, Nadia A.; Canpolat, Fuat E.; White, Susan M.; Quilis-Esquerra, Josep; Sanchez, Martin Morales; Gamundi, Maria José; Mochida, Ganeshwaran H.; Walsh, Christopher A.; Ali, Bassam R.; Al-Gazali, Lihadh

    2014-01-01

    We have recently shown that the hemorrhagic destruction of the brain, subependymal calcification and congenital cataracts is caused by biallelic mutations in the gene encoding junctional adhesion molecule 3 (JAM3) protein. Affected members from three new families underwent detailed clinical examination including imaging of the brain. Affected individuals presented with a distinctive phenotype comprising hemorrhagic destruction of the brain, subependymal calcification and congenital cataracts. All patients had a catastrophic clinical course resulting in death in 7 out of 10 affected individuals. Sequencing the coding exons of JAM3 revealed three novel homozygous mutations: c.2T>G (p.M1R), c.346G>A (p.E116K) and c.656G>A (p.C219Y). The p.M1R mutation affects the start codon and therefore is predicted to impair protein synthesis. Cellular studies showed that the p.C219Y mutation resulted in a significant retention of the mutated protein in the endoplasmic reticulum, suggesting a trafficking defect. The p.E116K mutant traffics normally to the plasma membrane as the wild type and may have lost its function due to the lack of interaction with an interacting partner. Our data further support the importance of JAM3 in the development and function of the vascular system and the brain. PMID:23255084

  11. Reversible lability by in situ reaction of self-assembled monolayers.

    PubMed

    Saavedra, Héctor M; Thompson, Christopher M; Hohman, J Nathan; Crespi, Vincent H; Weiss, Paul S

    2009-02-18

    We describe a new methodology for the fabrication of controllably displaceable monolayers using a carboxyl-functionalized self-assembled monolayer and in situ Fischer esterification, a simple and reversible chemical reaction. Using an 11-mercaptoundecanoic acid monolayer as a model system, we show that in situ esterification results in the creation of subtle chemical and structural defects. These defects promote molecular exchange reactions with n-dodecanethiol molecules, leading to the complete and rapid displacement of the exposed areas. Displacement results in well-ordered crystalline n-dodecanethiolate monolayer films. We also show that the complementary hydrolysis reaction can be employed to quench the reacted monolayer, significantly hindering further displacement. The generality of reversible lability was tested by applying the in situ esterification reaction to the structurally distinct carboxyl-functionalized molecule 3-mercapto-1-adamantanecarboxylic acid. Beyond its applicability to create mixed-composition monolayers, this methodology could be combined with chemical patterning techniques, such as microdisplacement printing, to fabricate complex functional surfaces. PMID:19170497

  12. Reactive oxygen species production by human dendritic cells involves TLR2 and dectin-1 and is essential for efficient immune response against Mycobacteria.

    PubMed

    Romero, María Mercedes; Basile, Juan Ignacio; Corra Feo, Laura; López, Beatriz; Ritacco, Viviana; Alemán, Mercedes

    2016-06-01

    Tuberculosis remains the single largest infectious disease with 10 million new cases and two million deaths that are estimated to occur yearly, more than any time in history. The intracellular replication of Mycobacterium tuberculosis (Mtb) and its spread from the lungs to other sites occur before the development of adaptive immune responses. Dendritic cells (DC) are professional antigen-presenting cells whose maturation is critical for the onset of the protective immune response against tuberculosis disease and may vary depending on the nature of the cell wall of Mtb strain. Here, we describe the role of the endogenous production of reactive oxygen species (ROS) on DC maturation and expansion of Mtb-specific lymphocytes. Here, we show that Mtb induces DC maturation through TLR2/dectin-1 by generating of ROS and through Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin (DC-SIGN) in a ROS independently manner. Based on the differences observed in the ability to induce DC maturation, ROS production and lymphocyte proliferation by those Mtb families widespread in South America, i.e., Haarlem and Latin American Mediterranean and the reference strain H37Rv, we propose that variance in ROS production might contribute to immune evasion affecting DC maturation and antigen presentation. PMID:26709456

  13. Host Langerin (CD207) is a receptor for Yersinia pestis phagocytosis and promotes dissemination

    PubMed Central

    Yang, Kun; Park, Chae G; Cheong, Cheolho; Bulgheresi, Silvia; Zhang, Shusheng; Zhang, Pei; He, Yingxia; Jiang, Lingyu; Huang, Hongping; Ding, Honghui; Wu, Yiping; Wang, Shaogang; Zhang, Lin; Li, Anyi; Xia, Lianxu; Bartra, Sara S; Plano, Gregory V; Skurnik, Mikael; Klena, John D; Chen, Tie

    2015-01-01

    Yersinia pestis is a Gram-negative bacterium that causes plague. After Y. pestis overcomes the skin barrier, it encounters antigen-presenting cells (APCs), such as Langerhans and dendritic cells. They transport the bacteria from the skin to the lymph nodes. However, the molecular mechanisms involved in bacterial transmission are unclear. Langerhans cells (LCs) express Langerin (CD207), a calcium-dependent (C-type) lectin. Furthermore, Y. pestis possesses exposed core oligosaccharides. In this study, we show that Y. pestis invades LCs and Langerin-expressing transfectants. However, when the bacterial core oligosaccharides are shielded or truncated, Y. pestis propensity to invade Langerhans and Langerin-expressing cells decreases. Moreover, the interaction of Y. pestis with Langerin-expressing transfectants is inhibited by purified Langerin, a DC-SIGN (DC-specific intercellular adhesion molecule 3 grabbing nonintegrin)-like molecule, an anti-CD207 antibody, purified core oligosaccharides and several oligosaccharides. Furthermore, covering core oligosaccharides reduces the mortality associated with murine infection by adversely affecting the transmission of Y. pestis to lymph nodes. These results demonstrate that direct interaction of core oligosaccharides with Langerin facilitates the invasion of LCs by Y. pestis. Therefore, Langerin-mediated binding of Y. pestis to APCs may promote its dissemination and infection. PMID:25829141

  14. Electrochemical serotonin monitoring of poly(ethylenedioxythiophene):poly(sodium 4-styrenesulfonate)-modified fluorine-doped tin oxide by predeposition of self-assembled 4-pyridylporphyrin.

    PubMed

    Song, Min-Jung; Kim, Sangsig; Ki Min, Nam; Jin, Joon-Hyung

    2014-02-15

    A 5,10,15,20-tetrakis(4-pyridyl)-21H,23H-porphyrin (TPyP)-modified self-assembled functional layer was prepared on a fluorine-doped tin oxide (FTO) substrate. We employed a bifunctional molecule, 3-iodopropionate (3IP), to covalently bind TPyP to the FTO substrate. The 3IP-monolayered FTO and the TPyP-3IP-bilayered FTO electrodes were characterized by cyclic voltammetry, electrochemical impedance spectroscopy, and Fourier transform-infrared spectroscopy. Compared to conventional electropolymerized poly(ethylenedioxythiophene):poly(sodium 4-styrenesulfonate) (PEDOT:PSS) film on bare FTO, the PEDOT:PSS film on the TPyP-3IP-bilayered FTO showed better sensitivity and selectivity in monitoring serotonin in the presence of high concentrations of interfering agents such as ascorbic acid, urea, D-(+)-glucose, epinephrine, and L-3,4-dihydroxyphenylalanine. Both PEDOT:PSS films on the bare FTO and the TPyP-3IP-bilayered FTO showed electrocatalytic effects in serotonin detection, and only the TPyP-3IP-based PEDOT:PSS film acted as a pH resistant buffer layer in the selective detection of serotonin. PMID:24125701

  15. Entangled states decoherence in coupled molecular spin clusters

    NASA Astrophysics Data System (ADS)

    Troiani, Filippo; Szallas, Attila; Bellini, Valerio; Affronte, Marco

    2010-03-01

    Localized electron spins in solid-state systems are widely investigated as potential building blocks of quantum devices and computers. While most efforts in the field have been focused on semiconductor low-dimensional structures, molecular antiferromagnets were recently recognized as alternative implementations of effective few-level spin systems. Heterometallic, Cr-based spin rings behave as effective spin-1/2 systems at low temperature and show long decoherence times [1]; besides, they can be chemically linked and magnetically coupled in a controllable fascion [2]. Here, we theoretically investigate the decoherence of the Bell states in such ring dimers, resulting from hyperfine interactions with nuclear spins. Based on a microscopic description of the molecules [3], we simulate the effect of inhomogeneous broadening, spectral diffusion and electron-nuclear entanglement on the electron-spin coherence, estimating the role of the different nuclei (and of possible chemical substitutions), as well as the effect of simple spin-echo sequences. References: [1] F. Troiani, et al., Phys. Rev. Lett. 94, 207208 (2005). [2] G. A. Timco, S: Carretta, F. Troiani et al., Nature Nanotech. 4, 173 (2009). [3] F. Troiani, V. Bellini, and M. Affronte, Phys. Rev. B 77, 054428 (2008).

  16. Electrolyte layering at the calcite(104)-water interface indicated by Rb+- and Se(VI) K-edge resonant interface diffraction

    SciTech Connect

    Heberling, F.; Eng, P.; Denecke, M. A.; Lützenkirchen, J.; Geckeis, H.

    2014-09-22

    Calcite–water interface reactions are of major importance in various environmental settings as well as in industrial applications. Here we present resonant interface diffraction results on the calcite(104)–aqueous solution interface, measured in solutions containing either 10 mmol L-1 RbCl or 0.5 mmol L-1 Se(VI). Results indicate that Rb+ ions enter the surface adsorbed water layers and adsorb at the calcite(104)–water interface in an inner-sphere fashion. A detailed analysis based on specular and off-specular resonant interface diffraction data reveals three distinct Rb+ adsorption species: one 1.2 Å above the surface, the second associated with surface adsorbed water molecules 3.2 Å above the surface, and the third adsorbed in an outer-sphere fashion 5.6 Å above the surface. A peak in resonant amplitude between L = 1.5 and L = 3.0 is interpreted as signal from a layered electrolyte structure. The presence of a layered electrolyte structure seems to be confirmed by data measured in the presence of Se(VI).

  17. Exciton diffusion in disordered small molecules for organic photovoltaics: insights from first-principles simulations.

    PubMed

    Li, Z; Zhang, X; Lu, G

    2014-05-01

    Exciton diffusion in small molecules 3,6-bis(5-(benzofuran-2-yl)thiophen-2-yl)-2,5-bis(2-ethylhexyl)pyrrolo[3,4-c]pyrrole-1,4-dione [DPP(TBFu)2] is studied using first-principles simulations. We have examined dependence of exciton diffusion on structure disorder, temperature and exciton energy. We find that exciton diffusion length and diffusivity increase with structural order, temperature and the initial exciton energy. Compared to conjugated polymer poly(3-hexylthiophene) (P3HT), DPP(TBFu)2 small molecules exhibit a much higher exciton diffusivity, but a shorter lifetime. The exciton diffusion length in DPP(TBFu)2 is 50% longer than that in P3HT, yielding a higher exciton harvesting efficiency; the physical origin behind these differences is discussed. The time evolutions of exciton energy, electron-hole distance, and exciton localization are explored, and the widely speculated exciton diffusion mechanism is confirmed theoretically. The connection between exciton diffusion and carrier mobilities is also studied. Finally we point out the possibility to estimate exciton diffusivity by measuring carrier mobilities under AC electric fields. PMID:24759042

  18. The effect of human immunodeficiency virus-1 on monocyte-derived dendritic cell maturation and function

    PubMed Central

    Fairman, P; Angel, J B

    2012-01-01

    Dendritic cells (DC) are mediators of the adaptive immune response responsible for antigen presentation to naive T cells in secondary lymph organs. Human immunodeficiency virus (HIV-1) has been reported to inhibit the maturation of DC, but a clear link between maturation and function has not been elucidated. To understand further the effects of HIV-1 on DC maturation and function, we expanded upon previous investigations and assessed the effects of HIV-1 infection on the expression of surface molecules, carbohydrate endocytosis, antigen presentation and lipopolysaccharide (LPS) responsiveness over the course of maturation. In vitro infection with HIV-1 resulted in an increase in the expression of DC-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) as well as decreases in maturation-induced CCR7 and major histocompatibility complex (MHC)-II expression. Retention of endocytosis that normally occurs with DC maturation as well as inhibition of antigen presentation to CD8+ T cells was also observed. Mitogen-activated protein kinase (MAPK) responsiveness to LPS as measured by phosphorylation of p38, c-Jun N-terminal kinase (JNK) and extracellular-regulated kinase (ERK)1/2 was not affected by HIV-1 infection. In summary, in-vitro HIV-1 impairs DC maturation, as defined by cell surface protein expression, with selective alterations in mature DC function. Understanding the mechanisms of DC dysfunction in HIV infection will provide further insight into HIV immune pathogenesis. PMID:22943206

  19. Topological insights into the 1/1 diacetyl/water complex gained using a new methodological approach.

    PubMed

    Dargent, D; Zins, E L; Madebène, B; Alikhani, M E

    2015-08-01

    The 1/1 diacetyl/water complex is of atmospheric relevance. Previous experimental and theoretical studies have focused on two isomeric forms, and geometry optimizations were carried out on them. Herein, we propose a six-step methodological approach based on topological properties to search for and characterize all of the isomeric forms of the 1/1 noncovalent diacetyl/water complex: (1) a molecular electrostatic potential (MESP) study to get an overview of the V min and V max regions on the molecular surfaces of the separate molecules (diacetyl and water); (2) a topological (QTAIM and ELF) study allowing thorough characterization of the electron densities (QTAIM) and irreducible ELF basins of the separate molecules; (3) full optimization of the predicted structures based on the interaction between complementary reaction sites; (4) energetic characterization based on a symmetry-adapted perturbation theory (SAPT) analysis; (5) topological characterization of the optimized complexes; (6) analysis of the complexes in terms of orbital overlaps (natural bond orbitals, NBO analysis). Using this approach, in addition to achieving the topological characterization of the two isomeric forms already reported, a third possible isomer was identified and characterized. Graphical Abstract Topological tools to study monohydrated complexes. PMID:26224601

  20. Glycoprotein B7-H3 overexpression and aberrant glycosylation in oral cancer and immune response

    PubMed Central

    Chen, Jung-Tsu; Chen, Chein-Hung; Ku, Ko-Li; Hsiao, Michael; Chiang, Chun-Pin; Hsu, Tsui-Ling; Chen, Min-Huey; Wong, Chi-Huey

    2015-01-01

    The incidence and mortality rate of oral cancer continue to rise, partly due to the lack of effective early diagnosis and increasing environmental exposure to cancer-causing agents. To identify new markers for oral cancer, we used a sialylation probe to investigate the glycoproteins differentially expressed on oral cancer cells. Of the glycoproteins identified, B7 Homolog 3 (B7-H3) was significantly overexpressed in oral squamous cell carcinoma (OSCC), and its overexpression correlated with larger tumor size, advanced clinical stage, and low survival rate in OSCC patients. In addition, knockdown of B7-H3 suppressed tumor cell proliferation, and restoration of B7-H3 expression enhanced tumor growth. It was also found that the N-glycans of B7-H3 from Ca9-22 oral cancer cells contain the terminal α-galactose and are more diverse with higher fucosylation and better interaction with DC-SIGN [DC-specific intercellular adhesion molecule-3 (ICAM-3)–grabbing nonintegrin] and Langerin on immune cells than that from normal cells, suggesting that the glycans on B7-H3 may also play an important role in the disease. PMID:26438868

  1. Conformational flexibility of mephenesin.

    PubMed

    Écija, Patricia; Evangelisti, Luca; Vallejo, Montserrat; Basterretxea, Francisco J; Lesarri, Alberto; Castaño, Fernando; Caminati, Walther; Cocinero, Emilio J

    2014-05-22

    The mephenesin molecule (3-(2-methylphenoxy)propane-1,2-diol) serves as a test bank to explore several structural and dynamical issues, such as conformational flexibility, the orientation of the carbon linear chain relative to the benzene plane, or the effect of substituent position on the rotational barrier of a methyl group. The molecule has been studied by rotational spectroscopy in the 4-18 GHz frequency range by Fourier-transform methods in a supersonic expansion. The experiment has been backed by a previous conformational search plus optimization of the lowest energy structures by ab initio and density functional quantum calculations. The three lowest-lying conformers that can interconvert to each other by simple bond rotations have been detected in the jet. Rotational parameters for all structures have been obtained, and methyl torsional barriers have been determined for the two lowest-lying rotamers. The lowest-lying structure of mephenesin is highly planar, with all carbon atoms lying nearly in the benzene ring plane, and is stabilized by the formation of cooperative intramolecular hydrogen bonding. An estimation of the relative abundance of the detected conformers indicates that the energetically most stable conformer will have an abundance near 80% at temperatures relevant for biological activity. PMID:24754523

  2. Phase I and phase II reductive metabolism simulation of nitro aromatic xenobiotics with electrochemistry coupled with high resolution mass spectrometry.

    PubMed

    Bussy, Ugo; Chung-Davidson, Yu-Wen; Li, Ke; Li, Weiming

    2014-11-01

    Electrochemistry combined with (liquid chromatography) high resolution mass spectrometry was used to simulate the general reductive metabolism of three biologically important nitro aromatic molecules: 3-trifluoromethyl-4-nitrophenol (TFM), niclosamide, and nilutamide. TFM is a pesticide used in the Laurential Great Lakes while niclosamide and nilutamide are used in cancer therapy. At first, a flow-through electrochemical cell was directly connected to a high resolution mass spectrometer to evaluate the ability of electrochemistry to produce the main reduction metabolites of nitro aromatic, nitroso, hydroxylamine, and amine functional groups. Electrochemical experiments were then carried out at a constant potential of -2.5 V before analysis of the reduction products by LC-HRMS, which confirmed the presence of the nitroso, hydroxylamine, and amine species as well as dimers. Dimer identification illustrates the reactivity of the nitroso species with amine and hydroxylamine species. To investigate xenobiotic metabolism, the reactivity of nitroso species to biomolecules was also examined. Binding of the nitroso metabolite to glutathione was demonstrated by the observation of adducts by LC-ESI(+)-HRMS and the characteristics of their MSMS fragmentation. In conclusion, electrochemistry produces the main reductive metabolites of nitro aromatics and supports the observation of nitroso reactivity through dimer or glutathione adduct formation. PMID:25234306

  3. Sulfated Escherichia coli K5 Polysaccharide Derivatives Inhibit Dengue Virus Infection of Human Microvascular Endothelial Cells by Interacting with the Viral Envelope Protein E Domain III

    PubMed Central

    Vervaeke, Peter; Alen, Marijke; Noppen, Sam; Schols, Dominique; Oreste, Pasqua; Liekens, Sandra

    2013-01-01

    Dengue virus (DENV) is an emerging mosquito-borne pathogen that causes cytokine-mediated alterations in the barrier function of the microvascular endothelium, leading to dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). We observed that DENV (serotype 2) productively infects primary (HMVEC-d) and immortalized (HMEC-1) human dermal microvascular endothelial cells, despite the absence of well-described DENV receptors, such as dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) or the mannose receptor on the cell surface. However, heparan sulfate proteoglycans (HSPGs) were highly expressed on these cells and pre-treatment of HMEC-1 cells with heparinase II or with glycosaminoglycans reduced DENV infectivity up to 90%, suggesting that DENV uses HSPGs as attachment receptor on microvascular endothelial cells. Sulfated Escherichia coli K5 derivatives, which are structurally similar to heparin/heparan sulfate but lack anticoagulant activity, were able to block DENV infection of HMEC-1 and HMVEC-d cells in the nanomolar range. The highly sulfated K5-OS(H) and K5-N,OS(H) inhibited virus attachment and subsequent entry into microvascular endothelial cells by interacting with the viral envelope (E) protein, as shown by surface plasmon resonance (SPR) analysis using the receptor-binding domain III of the E protein. PMID:24015314

  4. Understanding the movements of metal whiskers

    NASA Astrophysics Data System (ADS)

    Karpov, V. G.

    2015-06-01

    Metal whiskers often grow across leads of electric equipment causing short circuits and raising significant reliability issues. Their nature remains a mystery after several decades of research. It was observed that metal whiskers exhibit large amplitude movements under gentle air flow or, according to some testimonies, without obvious stimuli. Understanding the physics behind that movements would give additional insights into the nature of metal whiskers. Here, we quantitatively analyze possible mechanisms of the observed movements: (1) minute air currents; (2) Brownian motion due to random bombardments with the air molecules; (3) mechanically caused movements, such as (a) transmitted external vibrations, and (b) torque exerted due to material propagation along curved whiskers (the garden hose instability); (4) time dependent electric fields due to diffusion of ions; and (5) non-equilibrium electric fields making it possible for some whiskers to move. For all these mechanisms, we provide numerical estimates. Our conclusion is that the observed movements are likely due to the air currents or electric recharging caused by external light or similar factors.

  5. CNS myelin induces regulatory functions of DC-SIGN-expressing, antigen-presenting cells via cognate interaction with MOG.

    PubMed

    García-Vallejo, J J; Ilarregui, J M; Kalay, H; Chamorro, S; Koning, N; Unger, W W; Ambrosini, M; Montserrat, V; Fernandes, R J; Bruijns, S C M; van Weering, J R T; Paauw, N J; O'Toole, T; van Horssen, J; van der Valk, P; Nazmi, K; Bolscher, J G M; Bajramovic, J; Dijkstra, C D; 't Hart, B A; van Kooyk, Y

    2014-06-30

    Myelin oligodendrocyte glycoprotein (MOG), a constituent of central nervous system myelin, is an important autoantigen in the neuroinflammatory disease multiple sclerosis (MS). However, its function remains unknown. Here, we show that, in healthy human myelin, MOG is decorated with fucosylated N-glycans that support recognition by the C-type lectin receptor (CLR) DC-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN) on microglia and DCs. The interaction of MOG with DC-SIGN in the context of simultaneous TLR4 activation resulted in enhanced IL-10 secretion and decreased T cell proliferation in a DC-SIGN-, glycosylation-, and Raf1-dependent manner. Exposure of oligodendrocytes to proinflammatory factors resulted in the down-regulation of fucosyltransferase expression, reflected by altered glycosylation at the MS lesion site. Indeed, removal of fucose on myelin reduced DC-SIGN-dependent homeostatic control, and resulted in inflammasome activation, increased T cell proliferation, and differentiation toward a Th17-prone phenotype. These data demonstrate a new role for myelin glycosylation in the control of immune homeostasis in the healthy human brain through the MOG-DC-SIGN homeostatic regulatory axis, which is comprised by inflammatory insults that affect glycosylation. This phenomenon should be considered as a basis to restore immune tolerance in MS. PMID:24935259

  6. Temperature induced morphological transitions from native to unfolded aggregated States of human serum albumin.

    PubMed

    Das, Nirmal Kumar; Ghosh, Narayani; Kale, Ajit Prabhakar; Mondal, Ramakanta; Anand, Uttam; Ghosh, Subhadip; Tiwari, Virendra Kumar; Kapur, Manmohan; Mukherjee, Saptarshi

    2014-07-01

    The circulatory protein, human serum albumin (HSA), is known to have two melting point temperatures, 56 and 62 °C. In this present manuscript, we investigate the interaction of HSA with a synthesized bioactive molecule 3-pyrazolyl 2-pyrazoline (PZ). The sole tryptophan amino acid residue (Trp214) of HSA and PZ forms an excellent FRET pair and has been used to monitor the conformational dynamics in HSA as a function of temperature. Molecular docking studies reveal that the PZ binds to a site which is in the immediate vicinity of Trp214, and such data are also supported by time-resolved FRET studies. Steady-state and time-resolved anisotropy of PZ conclusively proved that the structural and morphological changes in HSA mainly occur beyond its first melting temperature. Although the protein undergoes thermal denaturation at elevated temperatures, the Trp214 gets buried inside the protein scaffolds; this fact has been substantiated by acrylamide quenching studies. Finally, we have used atomic force microscopy to establish that at around 70 °C, HSA undergoes self-assembly to form fibrillar structures. Such an observation may be attributed to the loss of α-helical content of the protein and a subsequent rise in β-sheet structure. PMID:24915234

  7. HPLC Plasma Assay of a Novel Anti-MRSA Compound, Kaempferol-3-O-Alpha-L-(2",3"-di-p-coumaroyl)rhamnoside, from Sycamore Leaves

    PubMed Central

    Zhang, Yiguan; Valeriote, Frederick; Swartz, Kenneth; Chen, Ben; Hamann, Mark T.; Rodenburg, Douglas L.; McChesney, James D.

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a serious pathogen that is resistant to current antibiotic therapy. Thus, there is an urgent need for novel antimicrobial agents that can effectively combat these new strains of drug-resistant “superbugs”. Recently, fractionation of an extract from Platanus occidentalis (American sycamore) leaves produced an active kaempferol molecule, 3-O-alpha-L-(2",3"-di-p-coumaroyl)rhamnoside (KCR), in four isomeric forms; all four isomers exhibit potent anti-MRSA activity. In order to further the preclinical development of KCR as a new antibiotic class, we developed and validated a simple analytical method for assaying KCR plasma concentration. Because KCR will be developed as a new drug, although comprising four stereoisomers, the analytical method was devised to assay the total amount of all four isomers. In the present work, both a plasma processing procedure and an HPLC method have been developed and validated. Mouse plasma containing KCR was first treated with ethanol and then centrifuged. The supernatant was dried, suspended in ethanol, centrifuged, and the supernatant was injected into an HPLC system comprising a Waters C18, a mobile phase composing methanol, acetonitrile, and trifluoroacetic acid and monitored at 313 nm. The method was validated by parameters including a good linear correlation, a limit of quantification of 0.27 µg/mL, and high accuracy. In summary, this method allows a rapid analysis of KCR in the plasma samples for pharmacokinetics studies. PMID:26434123

  8. Synthesis and biological evaluation of two new radiolabelled estrogens: [125I](E)-3-methoxy-17alpha-iodovinylestra-1,3,5(10),6-tetraen-17beta-ol and.

    PubMed

    Melo e Silva, M C; Patrćio, L; Gano, L; Sá e Melo, M L; Inohae, E; Mataka, S; Thiemann, T

    2001-02-01

    The synthesis of two novel radiolabelled estrogen derivatives, [125I](E)-3-methoxy-17alpha-iodovinylestra-1,3,5(10),6-tetraen-17beta-ol (E[125I]IVDE) and [125I](Z)-3-methoxy-17alpha-iodovinylestra-1,3,5(10),6-tetraen-17beta-ol (Z[125I]IVDE), was carried out aiming to study the influence of the introduction of a C6-C7 double bond on the biological properties of the estradiol molecule. 3-Methoxyestra-1,3,5(10),6-tetraen-17-one was synthesised starting from a suitably protected estrone and subsequently converted into the 17alpha-ethynyl derivative. The radioiodinated derivatives were stereoselectively formed by radioiododestannylation of the corresponding tributylstannyl precursors. The biodistribution of the novel [125I]iodovinylestradiol derivatives was evaluated in immature female mice. Biological data indicated that the Z-isomer, owing to its higher in vivo uptake by the target tissue, has the preferable configuration for further development of similar compounds for estrogen receptor detection. PMID:11200884

  9. Molecular photoionization studies

    SciTech Connect

    Dehmer, P.M.

    1983-01-01

    This program is concerned with the study of the electronic structure of small molecules and clusters of molecules. Of particular interest is the interaction of discrete electronic states with one another and with the various ionization and dissociation continua. Since the Second Annual Meeting of the DOE-OHER Program on The Physics and Chemistry of Energy-Related Atmospheric Pollutants in April 1981, significant progress has been made in the following areas: (1) the study of the electronic structure of dimers and small clusters of rare gas atoms using photoionization techniques; (2) similar studies on clusters of CO/sub 2/ molecules; (3) the study of electronic structure of rare gas dimers and trimers using photoelectron and photoelectron-photoion coincidence techniques; (4) the investigation of the relationship between Rydberg states in atoms, van der Waals molecules, and chemically-bonded molecules; (5) the extension of the study of photoabsorption, photoionization, and predissociation processes in H/sub 2/ to the unsymmetric isotope HD; (6) the study of photoelectron spectra of H/sub 2/ and C/sub 2/H/sub 2/; (7) a review of some of the aspects of dissociation processes in small molecules; and (8) the creation of a new program to study the spectra and dynamics of the photoionization processes in small molecules using the technique of multiphoton ionization followed by mass and electron energy analysis of the product ions and electrons. Some of the highlights of this work are reviewed.

  10. Two types of photoluminescence blinking revealed by single quantum dot spectroelectrochemistry

    PubMed Central

    Galland, Christophe; Ghosh, Yagnaseni; Steinbrück, Andrea; Sykora, Milan; Hollingsworth, Jennifer A.; Klimov, Victor I.; Htoon, Han

    2012-01-01

    Photoluminescence (PL) intermittency (blinking), or random switching between states of high- (ON) and low (OFF) emissivities, is a universal property of molecular emitters exhibited by dyes1, polymers2, biological molecules3 and artificial nanostructures such as nanocrystal quantum dots, carbon nanotubes, and nanowires4,5,6. For the past fifteen years, colloidal nanocrystals have been used as a model system for studies of this phenomenon.5,6 The occurrence of OFF periods in nanocrystal emission has been commonly attributed to the presence of an additional charge7, which leads to PL quenching by nonradiative Auger recombination.8 However, the “charging” model was recently challenged in several reports.9,10 Here, to clarify the role of charging in PL intermittency, we perform time-resolved PL studies of individual nanocrystals while controlling electrochemically the degree of their charging. We find that two distinct mechanisms can lead to PL intermittency. We identify conventional blinking (A-type) due to charging/discharging of the nanocrystal core when lower PL intensities correlate with shorter PL lifetimes. Importantly, we observe a different blinking (B-type), when large changes in the PL intensity are not accompanied by significant changes in PL dynamics. We attribute this blinking behavior to charge fluctuations in the electron-accepting surface sites. When unoccupied, these sites intercept hot electrons before they relax into emitting core states. Both blinking mechanisms can be controlled electrochemically and under appropriate potential blinking can be completely suppressed. PMID:22071764

  11. Noninvasive detection of weapons of mass destruction using terahertz radiation

    NASA Astrophysics Data System (ADS)

    Campbell, Matthew B.; Heilweil, Edwin J.

    2003-08-01

    The growing and immediate threat of biological and chemical weapons has placed urgency on the development of chemical and biological warfare agent (CWA/BWA) screening devices. Specifically, the ability to detect CWA/BWA prior to deployment is paramount to mitigating the threat without exposing individuals to its effects. SPARTA, Inc. and NIST are currently investigating the feasibility of using far-infrared radiation, or terahertz (THz, 1 THz = 1012 Hz) radiation, to non-invasively detect biological and chemical agents, explosives and drugs/narcotics inside sealed containers. Small-to-medium sized molecules (3-100 atoms) in gas, liquid and solid phases consistently exhibit identifiable spectral features in the far-IR portion of the spectrum. Many compounds associated with weapons of mass destruction are made up of molecules of this size. The THz portion of the spectrum lies between visible light and radio waves, allowing for partial transmission of 0.3-10.0 THz (30-1000 μm, 10-330 cm-1) light through most common materials. Therefore, transmission measurements of THz light can potentially be used to non-invasively detect the presence of CWA/BWA, explosives and drugs in the pathway of a THz radiation beam.

  12. Synthesis of an A-D-A type of molecule used as electron acceptor for improving charge transfer in organic solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Chao-Zhi; Gu, Shu-Duo; Shen, Dan; Yuan, Yang; Zhang, Mingdao

    2016-08-01

    Electron-accepting molecules play an important role in developing organic solar cells. A new type of A-D-A molecule, 3,6-di([7-(5-bromothiophen-2-yl)-1,5,2,4,6,8-dithiotetrazocin-3-yl]thiophen-2-yl)-9-(2-ethylhexyl)carbazole, was synthesized. The lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels are -3.55 and -5.85 eV, respectively. Therefore, the A-D-A type of compound could be used as electron acceptor for fabricating organic solar cell with a high open circuit voltage. Gibbs free energy (-49.2 kJ/mol) reveals that the process of A-D-A acceptor accepting an electron from poly(3-hexylthiophene) at excited state is spontaneous. The value of entropy (118 J/mol) in the process of an electron transferring from P3HT to the A-D-A acceptor at organic interface suggests that electrons generated from separation of electron-hole pairs at donor/acceptor interface would be delocalized efficiently. Therefore, the A-D-A molecule would be a potential acceptor for efficient organic BHJ solar cells.

  13. Electrolyte layering at the calcite(104)-water interface indicated by Rb(+)- and Se(VI) K-edge resonant interface diffraction.

    PubMed

    Heberling, F; Eng, P; Denecke, M A; Lützenkirchen, J; Geckeis, H

    2014-07-01

    Calcite-water interface reactions are of major importance in various environmental settings as well as in industrial applications. Here we present resonant interface diffraction results on the calcite(104)-aqueous solution interface, measured in solutions containing either 10 mmol L(-1) RbCl or 0.5 mmol L(-1) Se(VI). Results indicate that Rb(+) ions enter the surface adsorbed water layers and adsorb at the calcite(104)-water interface in an inner-sphere fashion. A detailed analysis based on specular and off-specular resonant interface diffraction data reveals three distinct Rb(+) adsorption species: one 1.2 Å above the surface, the second associated with surface adsorbed water molecules 3.2 Å above the surface, and the third adsorbed in an outer-sphere fashion 5.6 Å above the surface. A peak in resonant amplitude between L = 1.5 and L = 3.0 is interpreted as signal from a layered electrolyte structure. The presence of a layered electrolyte structure seems to be confirmed by data measured in the presence of Se(VI). PMID:24836466

  14. Size dependent transition to solid hydrogen and argon clusters probed via spectroscopy of PTCDA embedded in helium nanodroplets

    NASA Astrophysics Data System (ADS)

    Dvorak, Matthieu; Müller, Markus; Bünermann, Oliver; Stienkemeier, Frank

    2014-04-01

    Complexes made of either ArN or (H2)N clusters (N = 1-170) and a single PTCDA molecule (3,4,9,10-perylene-tetracarboxylic-dianhydride) are assembled inside helium droplets and spectroscopically studied via laser-induced fluorescence spectroscopy. The frequency shift and line-broadening are analyzed as a function of N and of the pick-up order of the PTCDA and cluster material in order to track liquid or solid properties of the clusters. For argon, the solid phase is observed for N > 10 above which the pick-up order dramatically influences the localization of the chromophore with respect to the Ar cluster. If the droplets are doped first with Ar, the chromophore remains on the surface of a solid cluster whereas for the reversed pick-up order the molecule is surrounded by an argon shell. At N < 10 wetting and the formation of the first solvation shell are observed. For para-hydrogen, a transition to the solid is observed at N ˜ 20-25, confirming previous theoretical predictions on the existence of a liquid-like phase at such small sizes, even below the bulk hydrogen freezing temperature.

  15. Size dependent transition to solid hydrogen and argon clusters probed via spectroscopy of PTCDA embedded in helium nanodroplets.

    PubMed

    Dvorak, Matthieu; Müller, Markus; Bünermann, Oliver; Stienkemeier, Frank

    2014-04-14

    Complexes made of either Ar(N) or (H2)N clusters (N = 1-170) and a single PTCDA molecule (3,4,9,10-perylene-tetracarboxylic-dianhydride) are assembled inside helium droplets and spectroscopically studied via laser-induced fluorescence spectroscopy. The frequency shift and line-broadening are analyzed as a function of N and of the pick-up order of the PTCDA and cluster material in order to track liquid or solid properties of the clusters. For argon, the solid phase is observed for N > 10 above which the pick-up order dramatically influences the localization of the chromophore with respect to the Ar cluster. If the droplets are doped first with Ar, the chromophore remains on the surface of a solid cluster whereas for the reversed pick-up order the molecule is surrounded by an argon shell. At N < 10 wetting and the formation of the first solvation shell are observed. For para-hydrogen, a transition to the solid is observed at N ~ 20-25, confirming previous theoretical predictions on the existence of a liquid-like phase at such small sizes, even below the bulk hydrogen freezing temperature. PMID:24735293

  16. Molecular gated transistors: Role of self-assembled monolayers

    NASA Astrophysics Data System (ADS)

    Shaya, O.; Halpern, E.; Khamaisi, B.; Shaked, M.; Usherenko, Y.; Shalev, G.; Doron, A.; Levy, I.; Rosenwaks, Y.

    2010-07-01

    In order to understand the biosensing mechanism of field-effect based biosensors and optimize their performance, the effect of each of its molecular building block must be understood. In this work the gating effect of self-assembled linker molecules on field-effect transistor was studied in detail. We have combined Kelvin probe force microscopy, current-voltage measurements, capacitance-voltage measurements, equivalent circuit modeling and device simulations in order to trace the mechanism of silicon-on-insulator biological field-effect transistors. The measurements were conducted on the widely used linker molecules (3-aminopropyl)-trimethoxysilane (APTMS) and 11-aminoundecyl-triethoxysilane (AUTES), which were self-assembled on ozone activated silicon oxide surface covering the transistor channel. In a dry environment, the work function of the modified silicon oxide decreased by more than 1.5 eV, and the transistor threshold voltage increased by about 30 V following the self-assembly. A detailed analysis indicates that these changes are due to negative induced charges on the top dielectric layer, and an effective dipole due to the polar monolayer. However, the self-assembly did not change the silicon flat-band voltage when in contact with an electrolyte. This is attributed to electrostatic screening by the electrolyte.

  17. Pseudomonas aeruginosa lasI/rhlI quorum sensing genes promote phagocytosis and aquaporin 9 redistribution to the leading and trailing regions in macrophages

    PubMed Central

    Holm, Angelika; Karlsson, Thommie; Vikström, Elena

    2015-01-01

    Pseudomonas aeruginosa controls production of its multiple virulence factors and biofilm development via the quorum sensing (QS) system. QS signals also interact with and affect the behavior of eukaryotic cells. Host water homeostasis and aquaporins (AQP) are essential during pathological conditions since they interfere with the cell cytoskeleton and signaling, and hereby affect cell morphology and functions. We investigated the contribution of P. aeruginosa QS genes lasI/rhlI to phagocytosis, cell morphology, AQP9 expression, and distribution in human macrophages, using immunoblotting, confocal, and nanoscale imaging. Wild type P. aeruginosa with a functional QS system was a more attractive prey for macrophages than the lasI/rhlI mutant lacking the production of QS molecules, 3O-C12-HSL, and C4-HSL, and associated virulence factors. The P. aeruginosa infections resulted in elevated AQP9 expression and relocalization to the leading and trailing regions in macrophages, increased cell area and length; bacteria with a functional QS system lasI/rhlI achieved stronger responses. We present evidence for a new role of water fluxes via AQP9 during bacteria–macrophage interaction and for the QS system as an important stimulus in this process. These novel events in the interplay between P. aeruginosa and macrophages may influence on the outcome of infection, inflammation, and development of disease. PMID:26388857

  18. A new class of hybrid anticancer agents inspired by the synergistic effects of curcumin and genistein: Design, synthesis, and anti-proliferative evaluation.

    PubMed

    Chen, Qiao-Hong; Yu, Kevin; Zhang, Xiaojie; Chen, Guanglin; Hoover, Andrew; Leon, Francisco; Wang, Rubing; Subrahmanyam, Nithya; Addo Mekuria, Ermias; Harinantenaina Rakotondraibe, Liva

    2015-10-15

    Inspired by the synergistic effects of dietary natural products with different scaffolds on the inhibition of cancer cell proliferation, incorporation of central (1E,4E)-1,4-penta-dien-3-one linker (an optimal substitute for the central metabolically unstable diketone linker of curcumin), 1-alkyl-1H-imidazol-2-yl (a promising bioisostere of terminal aryl group in curcumin), and chromone (the common pharmacophore in genistein and quercetin) into one chemical entity resulted in ten new hybrid molecules, 3-((1E,4E)-5-(1-alkyl-1H-imidazol-2-yl)-3-oxopenta-1,4-dien-1-yl)-4H-chromen-4-ones. They were synthesized through a three-step transformation using acid-catalyzed aldol condensation as key step. The WST-1 cell proliferation assay showed that they have greater anti-proliferative potency than curcumin, quercetin, and genistein on both androgen-dependent and androgen-independent human prostate cancer cells. PMID:26341135

  19. Recombination-stable multimeric green fluorescent protein for characterization of weak promoter outputs in Saccharomyces cerevisiae.

    PubMed

    Rugbjerg, Peter; Knuf, Christoph; Förster, Jochen; Sommer, Morten O A

    2015-12-01

    Green fluorescent proteins (GFPs) are widely used for visualization of proteins to track localization and expression dynamics. However, phenotypically important processes can operate at too low expression levels for routine detection, i.e. be overshadowed by autofluorescence noise. While GFP functions well in translational fusions, the use of tandem GFPs to amplify fluorescence signals is currently avoided in Saccharomyces cerevisiae and many other microorganisms due to the risk of loop-out by direct-repeat recombination. We increased GFP fluorescence by translationally fusing three different GFP variants, yeast-enhanced GFP, GFP+ and superfolder GFP to yield a sequence-diverged triple GFP molecule 3vGFP with 74-84% internal repeat identity. Unlike a single GFP, the brightness of 3vGFP allowed characterization of a weak promoter in S. cerevisiae. Utilizing 3vGFP, we further engineered a less leaky Cu(2+)-inducible promoter based on CUP1. The basal expression level of the new promoter was approximately 61% below the wild-type CUP1 promoter, thus expanding the absolute range of Cu(2+)-based gene control. The stability of 3vGFP towards direct-repeat recombination was assayed in S. cerevisiae cultured for 25 generations under strong and slightly toxic expression after which only limited reduction in fluorescence was detectable. Such non-recombinogenic GFPs can help quantify intracellular responses operating a low copy number in recombination-prone organisms. PMID:26392044

  20. General mechanism for modulating immunoglobulin effector function

    PubMed Central

    Sondermann, Peter; Pincetic, Andrew; Maamary, Jad; Lammens, Katja; Ravetch, Jeffrey V.

    2013-01-01

    Immunoglobulins recognize and clear microbial pathogens and toxins through the coupling of variable region specificity to Fc-triggered cellular activation. These proinflammatory activities are regulated, thus avoiding the pathogenic sequelae of uncontrolled inflammation by modulating the composition of the Fc-linked glycan. Upon sialylation, the affinities for Fcγ receptors are reduced, whereas those for alternative cellular receptors, such as dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN)/CD23, are increased. We demonstrate that sialylation induces significant structural alterations in the Cγ2 domain and propose a model that explains the observed changes in ligand specificity and biological activity. By analogy to related complexes formed by IgE and its evolutionarily related Fc receptors, we conclude that this mechanism is general for the modulation of antibody-triggered immune responses, characterized by a shift between an “open” activating conformation and a “closed” anti-inflammatory state of antibody Fc fragments. This common mechanism has been targeted by pathogens to avoid host defense and offers targets for therapeutic intervention in allergic and autoimmune disorders. PMID:23697368

  1. Synthesis of new liquid crystals embedded gold nanoparticles for photoswitching properties.

    PubMed

    Rahman, Md Lutfor; Biswas, Tapan Kumar; Sarkar, Shaheen M; Yusoff, Mashitah Mohd; Yuvaraj, A R; Kumar, Sandeep

    2016-09-15

    A new series of liquid crystals decorated gold nanoparticles is synthesized whose molecular architecture has azobenzenes moieties as the peripheral units connected to gold nanoparticles (Au NPs) via alkyl groups. The morphology and mesomorphic properties were investigated by field emission scanning electron microscope, high-resolution transmission electron microscopy, differential scanning calorimetry and polarizing optical microscopy. The thiolated ligand molecules (3a-c) showed enantiotropic smectic A phase, whereas gold nanoparticles (5a-c) exhibit nematic and smectic A phase with monotropic nature. HR-TEM measurement showed that the functionalized Au NPs are of the average size of 2nm and they are well dispersed without any aggregation. The trans-form of azo compounds showed a strong band in the UV region at ∼378nm for the π-π(∗) transition, and a weak band in the visible region at ∼472nm due to the n-π(∗) transition. These molecules exhibit attractive photoisomerization behaviour in which trans-cis transition takes about 15s whereas the cis-trans transition requires about 45min for compound 5c. The extent of reversible isomerization did not decay after 10 cycles, which proved that the photo-responsive properties of 5c were stable and repeatable. Therefore, these materials may be suitably exploited in the field of molecular switches and the optical storage devices. PMID:27341036

  2. Crystal structure of 4-[(E)-(4-hy-droxy-benzyl-idene)amino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one.

    PubMed

    Mague, Joel T; Akkurt, Mehmet; Mohamed, Shaaban K; Mohamed, Alaa F; Albayati, Mustafa R

    2015-12-01

    The asymmetric unit of the title compound, C18H17N3O2, comprises three independent mol-ecules (1, 2 and 3). In mol-ecule 1, the dihedral angles between the pyrazolone ring and the pendant phenyl and hydroxybenzene rings are 54.43 (6) and 28.72 (6)°, respectively. The corresponding data for mol-ecule 2 are 86.84 (6) and 25.69 (5)°, respectively, and for mol-ecule 3 are 47.41 (7) and 17.09 (7)°, respectively. The three mol-ecules feature an intra-molecular C-H⋯O inter-action, which closes an S(6) ring in each case. In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds, which generate [100] chains incorporating all three asymmetric mol-ecules. Two weak C-H⋯O interactions connect three independent molecules to each other along the c-axis direction. PMID:26870544

  3. High-Performance Silver Window Electrodes for Top-Illuminated Organic Photovoltaics Using an Organo-molybdenum Oxide Bronze Interlayer.

    PubMed

    Tyler, Martin S; Walker, Marc; Hatton, Ross A

    2016-05-18

    We report an organo-molybdenumn oxide bronze that enables the fabrication of high-performance silver window electrodes for top-illuminated solution processed organic photovoltaics without complicating the process of device fabrication. This hybrid material combines the function of wide-band-gap interlayer for efficient hole extraction with the role of metal electrode seed layer, enabling the fabrication of highly transparent, low-sheet-resistance silver window electrodes. Additionally it is also processed from ethanol, which ensures orthogonality with a large range of solution processed organic semiconductors. The key organic component is the low cost small molecule 3-mercaptopropionic acid, which (i) promotes metal film formation and imparts robustness at low metal thickness, (ii) reduces the contact resistance at the Ag/molybdenumn oxide bronze interface, (iii) and greatly improves the film forming properties. Silver electrodes with a thickness of 8 nm deposited by simple vacuum evaporation onto this hybrid interlayer have a sheet resistance as low as 9.7 Ohms per square and mean transparency ∼80% over the wavelength range 400-900 nm without the aid of an antireflecting layer, which makes them well-matched to the needs of organic photovoltaics and applicable to perovskite photovoltaics. The application of this hybrid material is demonstrated in two types of top-illuminated organic photovoltaic devices. PMID:27135377

  4. The old but new IgM Fc receptor (FcμR).

    PubMed

    Kubagawa, Hiromi; Kubagawa, Yoshiki; Jones, Dewitt; Nasti, Tahseen H; Walter, Mark R; Honjo, Kazuhito

    2014-01-01

    IgM is the first Ig isotype to appear during phylogeny, ontogeny and the immune response. The importance of both pre-immune "natural" and antigen-induced "immune" IgM antibodies in immune responses to pathogens and self-antigens has been established by studies of mutant mice deficient in IgM secretion. Effector proteins interacting with the Fc portion of IgM, such as complement and complement receptors, have thus far been proposed, but fail to fully account for the IgM-mediated immune protection and regulation of immune responses. Particularly, the role of the Fc receptor for IgM (FcμR) in such effector functions has not been explored until recently. We have identified an authentic FcμR in humans using a functional cloning strategy and subsequently in mice by RT-PCR and describe here its salient features and the immunological consequences of FcμR deficiency in mice. Since the FcμR we cloned was identical to Toso or Fas inhibitory molecule 3 (FAIM3), there have been spirited debates regarding the real function of FcμR/Toso/FAIM3 and we will also comment on this topic. PMID:25116093

  5. Chiral Sensitivity in the Dissociative Electron Attachment of Halocamphor Molecules

    NASA Astrophysics Data System (ADS)

    Dreiling, Joan

    2016-05-01

    We have demonstrated chirally-dependent molecular destruction when incident longitudinally-spin-polarized (chiral) electrons break bonds in chiral molecules. This chiral sensitivity was observed through an asymmetry in the dissociative electron attachment (DEA) reaction rate with chiral 3-bromocamphor (C10 H15 BrO). Such an observation provides an unambiguous demonstration of the idea underlying the Vester-Ulbricht hypothesis, which attempts to explain the origins of the homochirality that is observed in many biological systems. While the lack of inversion symmetry in these reactions allows the effects we observe to occur, their dynamic causes are poorly understood. We have further studied the asymmetries in the DEA rates for two additional halocamphor molecules, 3-iodocamphor (C10 H15 IO) and 10-iodocamphor, in a systematic effort to illuminate the mechanisms responsible for the chiral sensitivity. The DEA signal depends on the sign of the incident electron helicity for a given target handedness in all molecules, and it varies with both the atomic number and the location of the heaviest atom in the molecule. Surprisingly, the DEA asymmetries for 10-iodocamphor, in which the heaviest atom is farther from a chiral center than for the other molecules, produced the largest asymmetries. This work was performed at the University of Nebraska-Lincoln. This project was funded by NSF Grant PHY-1206067.

  6. Viral piracy: HIV-1 targets dendritic cells for transmission.

    PubMed

    Lekkerkerker, Annemarie N; van Kooyk, Yvette; Geijtenbeek, Teunis B H

    2006-04-01

    Dendritic cells (DCs), the professional antigen presenting cells, are critical for host immunity by inducing specific immune responses against a broad variety of pathogens. Remarkably the human immunodeficiency virus-1 (HIV-1) subverts DC function leading to spread of the virus. At an early phase of HIV-1 transmission, DCs capture HIV-1 at mucosal surfaces and transmit the virus to T cells in secondary lymphoid tissues. Capture of the virus on DCs takes place via C-type lectins of which the dendritic cell-specific intercellular adhesion molecule-3 (ICAM-3) grabbing nonintegrin (DC-SIGN) is the best studied. DC-SIGN-captured HIV-1 particles accumulate in CD81(+) multivesicular bodies (MVBs) in DCs and are subsequently transmitted to CD4+ T cells resulting in infection of T cells. The viral cell-to-cell transmission takes place at the DC-T cell interface termed the infectious synapse. Recent studies demonstrate that direct infection of DCs contributes to the transmission to T cells at a later phase. Moreover, the infected DCs may function as cellular reservoirs for HIV-1. This review discusses the different processes that govern viral piracy of DCs by HIV-1, emphasizing the intracellular routing of the virus from capture on the cell surface to egress in the infectious synapse. PMID:16611055

  7. EPR oxygen imaging and hyperpolarized 13C MRI of pyruvate metabolism as noninvasive biomarkers of tumor treatment response to a glycolysis inhibitor 3-bromopyruvate.

    PubMed

    Matsumoto, Shingo; Saito, Keita; Yasui, Hironobu; Morris, H Douglas; Munasinghe, Jeeva P; Lizak, Martin; Merkle, Hellmut; Ardenkjaer-Larsen, Jan Henrik; Choudhuri, Rajani; Devasahayam, Nallathamby; Subramanian, Sankaran; Koretsky, Alan P; Mitchell, James B; Krishna, Murali C

    2013-05-01

    The hypoxic nature of tumors results in treatment resistance and poor prognosis. To spare limited oxygen for more crucial pathways, hypoxic cancerous cells suppress mitochondrial oxidative phosphorylation and promote glycolysis for energy production. Thereby, inhibition of glycolysis has the potential to overcome treatment resistance of hypoxic tumors. Here, EPR imaging was used to evaluate oxygen dependent efficacy on hypoxia-sensitive drug. The small molecule 3-bromopyruvate blocks glycolysis pathway by inhibiting hypoxia inducible enzymes and enhanced cytotoxicity of 3-bromopyruvate under hypoxic conditions has been reported in vitro. However, the efficacy of 3-bromopyruvate was substantially attenuated in hypoxic tumor regions (pO2<10 mmHg) in vivo using squamous cell carcinoma (SCCVII)-bearing mouse model. Metabolic MRI studies using hyperpolarized 13C-labeled pyruvate showed that monocarboxylate transporter-1 is the major transporter for pyruvate and the analog 3-bromopyruvate in SCCVII tumor. The discrepant results between in vitro and in vivo data were attributed to biphasic oxygen dependent expression of monocarboxylate transporter-1 in vivo. Expression of monocarboxylate transporter-1 was enhanced in moderately hypoxic (8-15 mmHg) tumor regions but down regulated in severely hypoxic (<5 mmHg) tumor regions. These results emphasize the importance of noninvasive imaging biomarkers to confirm the action of hypoxia-activated drugs. PMID:22692861

  8. A comparison of force fields and calculation methods for vibration intervals of isotopic H3(+) molecules

    NASA Astrophysics Data System (ADS)

    Carney, G. D.; Adler-Golden, S. M.; Lesseski, D. C.

    1986-04-01

    This paper reports (1) improved values for low-lying vibration intervals of H3(+), H2D(+), D2H(+), and D3(+) calculated using the variational method and Simons-Parr-Finlan (1973) representations of the Carney-Porter (1976) and Dykstra-Swope (1979) ab initio H3(+) potential energy surfaces, (2) quartic normal coordinate force fields for isotopic H3(+) molecules, (3) comparisons of variational and second-order perturbation theory, and (4) convergence properties of the Lai-Hagstrom internal coordinate vibrational Hamiltonian. Standard deviations between experimental and ab initio fundamental vibration intervals of H3(+), H2D(+), D2H(+), and D3(+) for these potential surfaces are 6.9 (Carney-Porter) and 1.2/cm (Dykstra-Swope). The standard deviations between perturbation theory and exact variational fundamentals are 5 and 10/cm for the respective surfaces. The internal coordinate Hamiltonian is found to be less efficient than the previously employed 't' coordinate Hamiltonian for these molecules, except in the case of H2D(+).

  9. Zero-Mode Waveguide detection of biomolecules transport through artificial nanopores and nuclear pore complexes

    NASA Astrophysics Data System (ADS)

    Auger, Thomas; Auvray, Loic; Montel, Fabien

    We have developed a novel single molecule optical observation method using a custom Zero-Mode Waveguide setup to study the translocation of biopolymers through artificial and biological nanopores. Our work focuses on two aspects. First we monitored the flow driven injection of DNA molecules through solid state nanopores and showed that DNA starts translocating over a flow threshold independent of the pore radius, the DNA concentration and length. We demonstrate that the translocation is controlled by an energy barrier as proposed by the de Gennes - Brochard suction model. The height of the energy barrier can be modulated by functionalizing the nanopores with PEG-Thiols. More recently we adapted our setup to the study of transport through the nuclear pore complex (NPC) using extracted nuclear membranes from Xenopus Laevis oocytes. We aim at probing the conformation of unstructured proteins - the FG-Nucleoporins - crowding the central channel of the NPC by monitoring the free diffusion of small Dextran molecules (3kDa). We have been able to estimate the radius of the central pore of the NPC. We want to study the effects of transporter molecules, which have a high affinity for the FG-Nups, on the central pore size and correlate it to the conformation of FG-Nups.

  10. The statistical nature of the acetycholine potential and its molecular components.

    PubMed

    Katz, B; Miledi, R

    1972-08-01

    1. When a steady dose of acetylcholine (ACh) is applied to an end-plate, the resulting depolarization is accompanied by a significant increase in voltage noise.2. The characteristic properties of this ACh noise (amplitude and time course) are examined under various experimental conditions. The voltage noise is analysed on the assumption that it arises from statistical fluctuations in reaction rate, and in the frequency of the elementary current pulses (;shot effects') produced by the action of ACh molecules.3. The elementary ACh current pulse (amplitude approximately 10(-11) A), arises from a conductance change of the order of 10(-10) Omega(-1) which lasts for approximately 1 ms (at 20 degrees C), and produces a minute depolarization, of the order of 0.3 muV. It is associated with a net charge transfer of nearly 10(-14) C, equivalent to approximately 5 x 10(4) univalent ions.4. At low temperature, and during chronic denervation, the duration of the elementary current pulse increases, and the elementary voltage change becomes correspondingly larger.5. Curare has little or no effect on the characteristics of the elementary event.6. A comparative study of ACh and carbachol actions shows that carbachol produces considerably briefer, and therefore less effective, current pulses than ACh. PMID:5071933

  11. Host Langerin (CD207) is a receptor for Yersinia pestis phagocytosis and promotes dissemination.

    PubMed

    Yang, Kun; Park, Chae G; Cheong, Cheolho; Bulgheresi, Silvia; Zhang, Shusheng; Zhang, Pei; He, Yingxia; Jiang, Lingyu; Huang, Hongping; Ding, Honghui; Wu, Yiping; Wang, Shaogang; Zhang, Lin; Li, Anyi; Xia, Lianxu; Bartra, Sara S; Plano, Gregory V; Skurnik, Mikael; Klena, John D; Chen, Tie

    2015-10-01

    Yersinia pestis is a Gram-negative bacterium that causes plague. After Y. pestis overcomes the skin barrier, it encounters antigen-presenting cells (APCs), such as Langerhans and dendritic cells. They transport the bacteria from the skin to the lymph nodes. However, the molecular mechanisms involved in bacterial transmission are unclear. Langerhans cells (LCs) express Langerin (CD207), a calcium-dependent (C-type) lectin. Furthermore, Y. pestis possesses exposed core oligosaccharides. In this study, we show that Y. pestis invades LCs and Langerin-expressing transfectants. However, when the bacterial core oligosaccharides are shielded or truncated, Y. pestis propensity to invade Langerhans and Langerin-expressing cells decreases. Moreover, the interaction of Y. pestis with Langerin-expressing transfectants is inhibited by purified Langerin, a DC-SIGN (DC-specific intercellular adhesion molecule 3 grabbing nonintegrin)-like molecule, an anti-CD207 antibody, purified core oligosaccharides and several oligosaccharides. Furthermore, covering core oligosaccharides reduces the mortality associated with murine infection by adversely affecting the transmission of Y. pestis to lymph nodes. These results demonstrate that direct interaction of core oligosaccharides with Langerin facilitates the invasion of LCs by Y. pestis. Therefore, Langerin-mediated binding of Y. pestis to APCs may promote its dissemination and infection. PMID:25829141

  12. The Expression of the Hepatocyte SLAMF3 (CD229) Receptor Enhances the Hepatitis C Virus Infection

    PubMed Central

    Cartier, Flora; Marcq, Ingrid; Douam, Florian; Ossart, Christèle; Regnier, Aline; Debuysscher, Véronique; Lavillette, Dimitri; Bouhlal, Hicham

    2014-01-01

    Hepatitis C virus (HCV) is a leading cause of cirrhosis and liver cancer worldwide. We recently characterized for the first time the expression of Signaling Lymphocyte Activating Molecule 3 (SLAMF3) in human hepatocytes and here, we report that SLAMF3 interacts with the HCV viral protein E2 and is implicated in HCV entry process. We found a strong correlation between SLAMF3 expression level and hepatocyte susceptibility to HCV infection. The use of specific siRNAs to down-modulate SLAMF3 expression and SLAMF3-blocking antibodies both decreased the hepatocytes susceptibility to HCV infection. Moreover, SLAMF3 over-expression significantly increased susceptibility to HCV infection. Interestingly, experiments with peptides derived from each SLAMF3 domain showed that the first N-terminal extracellular domain is essential for interaction with HCV particles. Finally, we showed that recombinant HCV envelop protein E2 can bind SLAMF3 and that anti-SLAMF3 antibodies inhibited specifically this interaction. Overall, our results revealed that SLAMF3 plays a role during HCV entry, likely by enhancing entry of viral particle within hepatocytes. PMID:24927415

  13. Histology-directed and imaging mass spectrometry: an emerging technology in ectopic calcification

    PubMed Central

    De Santis, Giorgio; Caprioli, Richard M; Quaglino, Daniela

    2015-01-01

    The present study was designed to demonstrate the potential of an optimized histology directed protein identification combined with imaging mass spectrometry technology to reveal and identify molecules associated to ectopic calcification in human tissue. As a proof of concept, mineralized and non-mineralized areas were compared within the same dermal tissue obtained from a patient affected by Pseudoxanthoma elasticum, a genetic disorder characterized by calcification only at specific sites of soft connective tissues. Data have been technically validated on a contralateral dermal tissue from the same subject and compared with those from control healthy skin. Results demonstrate that this approach 1) significantly reduces the effects generated by techniques that, disrupting tissue organization, blend data from affected and unaffected areas; 2) demonstrates that, abolishing differences due to inter-individual variability, mineralized and non-mineralized areas within the same sample have a specific protein profile and have a different distribution of molecules; 3) avoiding the bias of focusing on already known molecules, reveals a number of proteins that have been never related to the disease nor to the calcification process, thus paving the way for the selection of new molecules to be validated as pathogenic or as potential pharmacological targets. PMID:25595835

  14. Destruction cross sections for fast hydrogen molecules incident on helium, neon, and argon

    SciTech Connect

    de Castro Faria, N.V.; Borges, I. Jr.; Coelho, L.F.S.; Jalbert, G.

    1995-05-01

    We measured the destruction cross sections of fast H{sub 2} molecules (3.0{le}{ital v}{le}7.0 a.u.) in helium, neon, and argon targets. We also measured, complementing previously published data, the H{sub 2}{sup +} destruction cross sections in neon for 3.0{le}{ital v}{le}7.0 a.u. and in helium and argon for {ital v}=3.0 a.u. The H{sub 2} beam was obtained from fast {ital H}{sub 3} molecules dissociated in an auxiliary target. These H{sub 2} and H{sub 2}{sup +} destruction cross sections were compared with the previous ones for H{sub 2}{sup +} and H{sub 3}{sup +} ions and also with the H electron-loss cross section, and a simple description is able to explain quantitatively the observed trends for these four sets of experiments, giving also information about the main destruction channels for the H{sub 2} and H{sub 2}{sup +} molecules.

  15. Dendritic cells respond to nasopharygeal carcinoma cells through annexin A2-recognizing DC-SIGN

    PubMed Central

    Cheng, Chao-Wen; Hsu, Tin-Jui; Lin, Yun-Tien; Lai, Chang-Hao; Liao, Chen-Chung; Chen, Wei-Yu; Leung, Ting-Kai; Lee, Fei-Peng; Lin, Yung-Feng; Chen, Chien-Ho

    2015-01-01

    Dendritic cells (DCs) play an essential role in immunity and are used in cancer immunotherapy. However, these cells can be tuned by tumors with immunosuppressive responses. DC-specific intercellular adhesion molecule 3-Grabbing Nonintegrin (DC-SIGN), a C-type lectin expressed on DCs, recognizes certain carbohydrate structures which can be found on cancer cells. Nasopharyngeal carcinoma (NPC) is an epithelial cell-derived malignant tumor, in which immune response remains unclear. This research is to reveal the molecular link on NPC cells that induces the immunosuppressive responses in DCs. In this article, we report identification of annexin A2 (ANXA2) on NPC cells as a ligand for DC-SIGN on DCs. N-linked mannose-rich glycan on ANXA2 may mediate the interaction. ANXA2 was abundantly expressed in NPC, and knockdown of ANXA2 suppressed NPC xenograft in mice, suggesting a crucial role of ANXA2 in NPC growth. Interaction with NPC cells caused DC-SIGN activation in DCs. Consequently DC maturation and the proinflammatory interleukin (IL)-12 production were inhibited, and the immunosuppressive IL-10 production was promoted. Blockage of either DC-SIGN or ANXA2 eliminated the production of IL-10 from DCs. This report suggests that suppression of ANXA2 at its expression or glycosylation on NPC may improve DC-mediated immunotherapy for the tumor. PMID:25402728

  16. PTCDA on Cu(111) partially covered with NaCl.

    PubMed

    Karacuban, H; Koch, S; Fendrich, M; Wagner, Th; Möller, R

    2011-07-22

    The organic molecule 3,4,9,10-perylene-tetracarboxylic dianhydride (PTCDA) was studied by means of scanning tunneling microscopy (STM) on thin insulating NaCl films grown on a Cu(111) single crystal. The deposition of approximately two monolayers (ML) of sodium chloride onto a Cu(111) substrate at a sample temperature of about 350 K causes a rather rough growth of (100)-oriented NaCl islands up to a local height of 4 ML. For submonolayer coverages (0.1 and 0.4 ML) of PTCDA on a Cu(111) surface partly covered with NaCl, two different rod structures of PTCDA were found on the copper surface, which are in contrast to previously published data for PTCDA on Cu(111) showing a herringbone-like arrangement. These findings can be explained by the formation of a Na(x)-PTCDA complex. On NaCl covered areas, single PTCDA molecules adsorb at vacancies of [010] and [001] oriented steps of the NaCl(100) islands. In this case, the electrostatic forces between the polar step edges and the PTCDA molecules are dominant. The terraces of the alkali halide surface are free of PTCDA molecules. PMID:21693798

  17. Action of reactive oxygen species in the antifungal mechanism of gemini-pyridinium salts against yeast.

    PubMed

    Shirai, Akihiro; Ueta, Shouko; Maseda, Hideaki; Kourai, Hiroki; Omasa, Takeshi

    2012-06-01

    We previously found that the gemini quaternary salt (gemini-QUAT) containing two pyridinium residues per molecule, 3,3'- (2,7-dioxaoctane) bis (1-decylpyridinium bromide) (3DOBP-4,10) , exerted fungicidal activity against Saccharomyces cerevisiae and caused respiration inhibition and the cytoplasmic leakage of ATP, magnesium, and potassium ions. Here, we investigated how the gemini-QUAT, 3DOBP-4,10, exerts more powerful antimicrobial activity than the mono-QUAT N-cetylpyridinium chloride (CPC) and examined the association between reactive oxygen species (ROS) and the antimicrobial mechanism. Antifungal assays showed that the activity of 3DOBP-4,10 against two yeasts, S. cerevisiae and Candida albicans, was significantly elevated under aerobic conditions, and largely reduced under anaerobic conditions (nitrogen atmosphere) . Adding radical scavengers such as superoxide dismutase, catalase and potassium iodide (KI) also decreased the fungicidal activity of 3DOBP-4,10 but negligibly affected that of CPC. We measured survival under static conditions and found that the rapid fungicidal profile of 3DOBP-4,10 was lost, whereas that of CPC was slightly affected in the presence of KI. Our results suggest that 3DOBP-4,10 exerts powerful antimicrobial activity by penetrating the cell wall and membrane, which then allows oxygen to enter the cells, where it participates in the generation of intracellular ROS. The activity could thus be attributable to a synergic antimicrobial combination of the disruption of organelle membranes by the QUAT and oxidative stress imposed by ROS. PMID:22790843

  18. A turn-on fluorescent nanoprobe for selective determination of selenium(IV).

    PubMed

    Liang, Song; Chen, Jiao; Pierce, David T; Zhao, Julia Xiaojun

    2013-06-12

    A turn-on fluorescent nanoprobe was developed for selective determination of selenium(IV). A trace amount of selenium, as an essential nutrient, plays an important role in human health. It has been proven that a selenium deficiency will result in serious health problems. The developed nanoprobe is capable of in situ detection of selenium with target-induced signaling, and no separation step is needed. The nanoprobe consists of a silica nanoparticle core and a coating layer containing selenium(IV)-induced fluorescent molecules, 3,3'-diaminobenzidine (DAB). The nanoprobes have no fluorescence signals if they are not exposed to selenium(IV). However, the nanoprobes will be "turned on", with fluorescence, when they bind to the targets of selenium(IV). With this strategy, the selenium(IV) are first collected and enriched on a small domain of the nanoprobes. Then, with an excitation at 420 nm, the nanoprobes emit fluorescence signals at 530 nm. The fluorescence intensity is proportional to the selenium concentration. A fluorescence microscope was used to monitor the process of enriching and collecting of the selenium(IV) by the nanoprobes. The optimal conditions for the determination of selenium(IV) using the nanoprobe were investigated including pH, solvent, and linear range. The interference from common metal ions was studied as well. This study is expected to shed light on how to design turn-on fluorescent nanoprobes for in situ monitoring of a wide variety of targets in biological processes. PMID:23676764

  19. Synthesis, photophysical and electrochemical properties of two novel carbazole-based dye molecules

    NASA Astrophysics Data System (ADS)

    Zhang, Qing; Zhu, Weiju; Fang, Min; Yin, Fangfang; Li, Cun

    2015-01-01

    Two carbazole-based dye molecules: 3-(6-benzothiazol-2-yl-9H-hexylcarbazole-3-yl)-2-cyano-acylic acid (D3) and 3-[5-(6-benzothiazol-2-yl-9H-hexylcarbazole-3-yl)-thiophen-2-yl]-2-cyan-acylic acid (D4) were synthesized by an approach from carbazole derivate using Vilsmeier-Haack, Suzuki cross-coupling and Knoevenagel reactions. Their physical and electrochemical properties were investigated. D3 and D4 exhibit different optical properties, such as UV absorption, photoluminescence, fluorescence quantum yield and fluorescence lifetime in different solvents. Compared with D3 without a thiophene unit, the maximum absorption wavelength of D4 red-shift obviously and its fluorescence intensity is also enhanced. A shift of the EHOMO and ELUMO is observed for D3 (EHOMO = 2.06 V, ELUMO = -1.39 V vs. NHE) and D4 (EHOMO = 1.73 V, ELUMO = -1.33 V vs. NHE). D3 and D4 can be used as dyes for dye-sensitized solar cells (DSSCs) with TiO2 nanomaterial because their EHOMO are lower than the conduction band edge of TiO2 [-0.5 V (vs. NHE)] and their ELUMO are higher than the I3-/I- redox potential [0.42 V (vs. NHE)].

  20. Synthesis, photophysical and electrochemical properties of two novel carbazole-based dye molecules.

    PubMed

    Zhang, Qing; Zhu, Weiju; Fang, Min; Yin, Fangfang; Li, Cun

    2015-01-25

    Two carbazole-based dye molecules: 3-(6-benzothiazol-2-yl-9H-hexylcarbazole-3-yl)-2-cyano-acylic acid (D3) and 3-[5-(6-benzothiazol-2-yl-9H-hexylcarbazole-3-yl)-thiophen-2-yl]-2-cyan-acylic acid (D4) were synthesized by an approach from carbazole derivate using Vilsmeier-Haack, Suzuki cross-coupling and Knoevenagel reactions. Their physical and electrochemical properties were investigated. D3 and D4 exhibit different optical properties, such as UV absorption, photoluminescence, fluorescence quantum yield and fluorescence lifetime in different solvents. Compared with D3 without a thiophene unit, the maximum absorption wavelength of D4 red-shift obviously and its fluorescence intensity is also enhanced. A shift of the EHOMO and ELUMO is observed for D3 (EHOMO=2.06 V, ELUMO=-1.39 V vs. NHE) and D4 (EHOMO=1.73 V, ELUMO=-1.33 V vs. NHE). D3 and D4 can be used as dyes for dye-sensitized solar cells (DSSCs) with TiO2 nanomaterial because their EHOMO are lower than the conduction band edge of TiO2 [-0.5 V (vs. NHE)] and their ELUMO are higher than the I(3-)/I(-) redox potential [0.42 V (vs. NHE)]. PMID:25104283

  1. Density functional study of CO adsorption on d-metal surface using TPSS functional

    NASA Astrophysics Data System (ADS)

    Sun, Jianwei; Perdew, John

    2009-03-01

    Feibelman et al^[1] presented the puzzle of CO at the Pt(111) surface, showing that the LDA and Perdew-type GGA put the molecule at the wrong, high-coordination site. However, a recent study ^[2] showed that the BLYP yielded very satisfactory adsorption energies and the correct adsorption sites for CO adsorption on late 4d and 5d transition metal (111) surfaces, although at the price of large errors in the volume of the d metals. Since PBE and BLYP have similar accuracy, it seems the probable reason for the wrong adsorption site is due to the fact that the LDA and Perdew-type GGA's are ``jellium derived'' and hence prefer a more delocalized bonding, rather than that the LDA and GGA inaccurately describe the CO molecule's chemical bond. TPSS meta-GGA is also ``jellium derived'', but improves accuracy for molecules^[3]. Therefore, as a possible candidate to identify the major reason for the wrong adsorption site, TPSS is used to calculate the adsorption energies and sites of CO on the d-metal surface in the more accurate geometric structure obtained by PBEsol^[4]. [1] P.J. Feibelman et al, J. Phys. Chem. 105, 4018(2001). [2] A. Stroppa and G. Kresse, New Journal of Physics 10, 063020(2008). [3] V.N. Staroverov et al, J. Chem. Phys., 119, 12129(2003). [4] J.P. Perdew et al, Phys. Rev. Lett., 100, 136406(2008).

  2. Quasiparticle spectra from a nonempirical optimally tuned range-separated hybrid density functional

    SciTech Connect

    Refaely-Abramson, Sivan; Sharifzadeh, Sahar; Govind, Niranjan; Autschbach, Jochen; Neaton, Jeffrey B.; Baer, Roi; Kronik, Leeor

    2012-11-28

    We present a method for obtaining quasiparticle excitation energies from a DFT-based calculation, but with accuracy that is comparable to that of many-body perturbation theory within the GW approximation. The approach uses a range-separated hybrid density functional, with asymptotically exact and short-range fractional Fock exchange. The functional contains two parameters - the range separation and the short-range Fock fraction. Both are determined non-empirically, per system, based on satisfaction of exact physical constraints for the ionization potential and many-electron self-interaction, respectively. The accuracy of the method is demonstrated on the important benchmark molecule, 3,4,9,10-perylene-tetracarboxylic-dianydride (PTCDA), where it is shown to be the only non-empirical DFT-based method comparable to GW calculations. For any finite system, we envision that the approach could be useful directly as an inexpensive alternative to GW that offers good accuracy for both frontier and non-frontier quasiparticle excitation energies, opening the door to the studyof presently out of reach large-scale systems.

  3. Design of water molecule and its surrounding

    NASA Astrophysics Data System (ADS)

    Danylo, R. I.; Okhrimenko, B. A.; Yablochkova, K. S.

    2015-02-01

    Hydrogen bonds and their fluctuations are one of the factors that determine the unique properties of water [1]. Building models of formation and rupture of hydrogen bonds due to non-eigen vibrations of a molecule of water is to a large extent determined by the availability of accurate information on the geometric structure of the water molecule. Geometric parameters of the water molecule have been well studied for the gaseous state. This was aided by the possibility of an experimental study of the regularities in the rotational spectra of molecules. However, some questions about the geometry of the water molecule in the liquid state remain unanswered. For example, many sources state that the valence angle of the water molecule decreases during the transition into the liquid state [2]. Based on the experimental data of molecular vibration spectra in D2O and H2O molecules [3], the authors have estimated valence angle of water in the liquid state. Consequently, the value of the valence angle of water in liquid state was determined to be (89 +/-2)°. A question of determination of libration vibrations of water molecule, as well as the analysis of its consequent inversion doubling, based on the new information on the equilibrium angle of the water molecules in the liquid state, constitutes an interest and is discussed in the present paper.

  4. Tissue-Specific Inactivation of Type 2 Deiodinase Reveals Multilevel Control of Fatty Acid Oxidation by Thyroid Hormone in the Mouse

    PubMed Central

    Fonseca, Tatiana L.; Werneck-De-Castro, Joao Pedro; Castillo, Melany; Bocco, Barbara M.L.C.; Fernandes, Gustavo W.; McAninch, Elizabeth A.; Ignacio, Daniele L.; Moises, Caio C.S.; Ferreira, Alexandre; Gereben, Balázs

    2014-01-01

    Type 2 deiodinase (D2) converts the prohormone thyroxine (T4) to the metabolically active molecule 3,5,3′-triiodothyronine (T3), but its global inactivation unexpectedly lowers the respiratory exchange rate (respiratory quotient [RQ]) and decreases food intake. Here we used FloxD2 mice to generate systemically euthyroid fat-specific (FAT), astrocyte-specific (ASTRO), or skeletal-muscle-specific (SKM) D2 knockout (D2KO) mice that were monitored continuously. The ASTRO-D2KO mice also exhibited lower diurnal RQ and greater contribution of fatty acid oxidation to energy expenditure, but no differences in food intake were observed. In contrast, the FAT-D2KO mouse exhibited sustained (24 h) increase in RQ values, increased food intake, tolerance to glucose, and sensitivity to insulin, all supporting greater contribution of carbohydrate oxidation to energy expenditure. Furthermore, FAT-D2KO animals that were kept on a high-fat diet for 8 weeks gained more body weight and fat, indicating impaired brown adipose tissue (BAT) thermogenesis and/or inability to oxidize the fat excess. Acclimatization of FAT-D2KO mice at thermoneutrality dissipated both features of this phenotype. Muscle D2 does not seem to play a significant metabolic role given that SKM-D2KO animals exhibited no phenotype. The present findings are unique in that they were obtained in systemically euthyroid animals, revealing that brain D2 plays a dominant albeit indirect role in fatty acid oxidation via its sympathetic control of BAT activity. D2-generated T3 in BAT accelerates fatty acid oxidation and protects against diet-induced obesity. PMID:24487027

  5. Synthesis of low color, atomic oxygen resistant polyimides

    NASA Technical Reports Server (NTRS)

    MacInnes, Dave

    1995-01-01

    The purpose of this project was to develop low color, atomic oxygen resistant polyimides for potential applications on spacecraft in low earth orbit. The material is needed in order to protect satellites and spacecraft from the gases and radiation found at those altitudes. Phosphorous containing polyimides have been shown to be especially resistant to corrosion and weight loss under oxygen plasma. Unfortunately the color of these phosphorous containing polyimides is still too high for them to be good heat insulators. While they are not as effective as teflon, the current material of choice. polyimides are much less dense than teflon and would be especially valuable if they could be made with low color. The approach taken was to synthesize a monomer which would contain the elements needed for giving the final polyimide its desired properties. In particular the monomer should incorporate phosphine or phosphine oxides and have bulky side groups to block any color forming charge transfer structures. The target molecule, 3,5-di-(trifluoromethylphenyl)-bis(3-aminophenyl) phosphine oxide, (containing both a phosphine oxide group and a bulky ditrifluoromethylphenyl group) was synthesized via three reactions in overall yield of 21 percent. In addition, a model compound, bis(3-phenylamine) phenyl phosphine oxide, was synthesized two different ways in order to establish the conditions for the nitration of phosphine oxides and their reduction to the amine. Finally, a trisubstituted phosphine oxide was synthesized. In all, seven phosphorus containing organic compounds were synthesized, purified and characterized. The model compound was reacted with oxydiphthalic anhydride to form a polyamic acid with inherent viscosity of 0.34. This material was cast into a film and heated, forming a normally colored fairly strong polyimide with a Tg of 240 C. The target compound was reacted with 6-fluorodiphthalic anhydride to give a polyamic acid with inherent viscosity of 0.19 and cast to

  6. A tandem mass spectrometric study of bile acids: interpretation of fragmentation pathways and differentiation of steroid isomers.

    PubMed

    Qiao, Xue; Ye, Min; Liu, Chun-fang; Yang, Wen-zhi; Miao, Wen-juan; Dong, Jing; Guo, De-an

    2012-02-01

    Bile acids are steroids with a pentanoic acid substituent at C-17. They are the terminal products of cholesterol excretion, and play critical physiological roles in human and animals. Bile acids are easy to detect but difficult to identify by using mass spectrometry due to their poly-ring structure and various hydroxylation patterns. In this study, fragmentation pathways of 18 free and conjugated bile acids were interpreted by using tandem mass spectrometry. The analyses were conducted on ion trap and triple quadrupole mass spectrometers. Upon collision-induced dissociation, the conjugated bile acids could cleave into glycine or taurine related fragments, together with the steroid skeleton. Fragmentations of free bile acids were further elucidated, especially by atmospheric pressure chemical ionization mass spectrometry in positive ion mode. Aside from universally observed neutral losses, eliminations occurred on bile acid carbon rings were proposed for the first time. Moreover, four isomeric 5β-cholanic acid hydroxyl derivatives (3α,6α-, 3α,7β-, 3α,7α-, and 3α,12α-) were differentiated using electrospray ionization in negative ion mode: 3α,7β-OH substituent inclined to eliminate H(2)O and CH(2)O(2) groups; 3α,6α-OH substituent preferred neutral loss of two H(2)O molecules; 3α,12α-OH substituent apt to lose the carboxyl in the form of CO(2) molecule; and 3α,7α-OH substituent exhibited no further fragmentation after dehydration. This study provided specific interpretation for mass spectra of bile acids. The results could contribute to bile acid analyses, especially in clinical assays and metabonomic studies. PMID:22133544

  7. Directed evolution of the quorum-sensing regulator EsaR for increased signal sensitivity.

    PubMed

    Shong, Jasmine; Huang, Yao-Ming; Bystroff, Christopher; Collins, Cynthia H

    2013-04-19

    The use of cell-cell communication or "quorum sensing (QS)" elements from Gram-negative Proteobacteria has enabled synthetic biologists to begin engineering systems composed of multiple interacting organisms. However, additional tools are necessary if we are to progress toward synthetic microbial consortia that exhibit more complex, dynamic behaviors. EsaR from Pantoea stewartii subsp. stewartii is a QS regulator that binds to DNA as an apoprotein and releases the DNA when it binds to its cognate signal molecule, 3-oxohexanoyl-homoserine lactone (3OC6HSL). In the absence of 3OC6HSL, EsaR binds to DNA and can act as either an activator or a repressor of transcription. Gene expression from P(esaR), which is repressed by wild-type EsaR, requires 100- to 1000-fold higher concentrations of signal than commonly used QS activators, such as LuxR and LasR. Here we have identified EsaR variants with increased sensitivity to 3OC6HSL using directed evolution and a dual ON/OFF screening strategy. Although we targeted EsaR-dependent derepression of P(esaR), our EsaR variants also showed increased 3OC6HSL sensitivity at a second promoter, P(esaS), which is activated by EsaR in the absence of 3OC6HSL. Here, the increase in AHL sensitivity led to gene expression being turned off at lower concentrations of 3OC6HSL. Overall, we have increased the signal sensitivity of EsaR more than 70-fold and generated a set of EsaR variants that recognize 3OC6HSL concentrations ranging over 4 orders of magnitude. QS-dependent transcriptional regulators that bind to DNA and are active in the absence of a QS signal represent a new set of tools for engineering cell-cell communication-dependent gene expression. PMID:23363022

  8. Prospects for T cell immunotherapy of tumours by vaccination with immunodominant and subdominant peptides.

    PubMed

    Melief, C J; Kast, W M

    1994-01-01

    Immunotherapy of tumours by adoptive transfer of cytotoxic T lymphocytes (CTL) is now feasible in experimental murine systems. These CTL recognize peptide sequences of defined length presented by major histocompatibility complex (MHC) class I molecules. Effective eradication of large tumour masses requires co-administration of interleukin 2. Tumour escape strategies are numerous but in various instances can be counteracted by defined measures. Initiation of CTL responses against poorly immunogenic virally induced tumours and other tumours requires novel strategies to overcome T cell inertia. We propose a strategy in which CTL are raised against target molecules of choice including differentiation antigens of restricted tissue distribution (autoantigens) or mutated/overexpressed oncogene products. The steps proposed include: (1) identification of target molecules of choice. (2) Identification in these target molecules of peptides fitting MHC allele-specific peptide motifs involved in peptide binding to MHC molecules. (3) Evaluation of actual binding of such peptides to specific MHC class I molecules. (4) In vitro CTL response induction by such peptides, presented by highly efficient antigen-presenting cells such as antigen processing-defective cells carrying empty MHC class I molecules loaded with a single peptide or dendritic cells. Both types of cells are capable of primary CTL response induction in vitro. (5) Evaluation of proper processing by the demonstration of tumour cell lysis by these CTL. (6) Adoptive transfer of tumour-specific CTL generated in vitro or vaccination with peptides. These various steps have now been taken for several viruses, virally induced tumours and other types of tumours and the first indications that this strategy is useful have been obtained. PMID:7796678

  9. Analysis of the magnetically induced current density of molecules consisting of annelated aromatic and antiaromatic hydrocarbon rings.

    PubMed

    Sundholm, Dage; Berger, Raphael J F; Fliegl, Heike

    2016-06-21

    Magnetically induced current susceptibilities and current pathways have been calculated for molecules consisting of two pentalene groups annelated with a benzene (1) or naphthalene (2) moiety. Current strength susceptibilities have been obtained by numerically integrating separately the diatropic and paratropic contributions to the current flow passing planes through chosen bonds of the molecules. The current density calculations provide novel and unambiguous current pathways for the unusual molecules with annelated aromatic and antiaromatic hydrocarbon moieties. The calculations show that the benzene and naphthalene moieties annelated with two pentalene units as in molecules 1 and 2, respectively, are unexpectedly antiaromatic sustaining only a local paratropic ring current around the ring, whereas a weak diatropic current flows around the C-H moiety of the benzene ring. For 1 and 2, the individual five-membered rings of the pentalenes are antiaromatic and a slightly weaker semilocal paratropic current flows around the two pentalene rings. Molecules 1 and 2 do not sustain any net global ring current. The naphthalene moiety of the molecule consisting of a naphthalene annelated with two pentalene units (3) does not sustain any strong ring current that is typical for naphthalene. Instead, half of the diatropic current passing the naphthalene moiety forms a zig-zag pattern along the C-C bonds of the naphthalene moiety that are not shared with the pentalene moieties and one third of the current continues around the whole molecule partially cancelling the very strong paratropic semilocal ring current of the pentalenes. For molecule 3, the pentalene moieties and the individual five-membered rings of the pentalenes are more antiaromatic than for 1 and 2. The calculated current patterns elucidate why the compounds with formally [4n + 2] π-electrons have unusual aromatic properties violating the Hückel π-electron count rule. The current density calculations also provide

  10. Human Milk Blocks DC-SIGN-Pathogen Interaction via MUC1.

    PubMed

    Koning, Nathalie; Kessen, Sabine F M; Van Der Voorn, J Patrick; Appelmelk, Ben J; Jeurink, Prescilla V; Knippels, Leon M J; Garssen, Johan; Van Kooyk, Yvette

    2015-01-01

    Beneficial effects of breastfeeding are well-recognized and include both immediate neonatal protection against pathogens and long-term protection against allergies and autoimmune diseases. Although several proteins have been identified to have anti-viral or anti-bacterial effects like secretory IgA or lactoferrin, the mechanisms of immune modulation are not fully understood. Recent studies identified important beneficial effects of glycans in human milk, such as those expressed in oligosaccharides or on glycoproteins. Glycans are recognized by the carbohydrate receptors C-type lectins on dendritic cell (DC) and specific tissue macrophages, which exert important functions in immune modulation and immune homeostasis. A well-characterized C-type lectin is dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN), which binds terminal fucose. The present study shows that in human milk, MUC1 is the major milk glycoprotein that binds to the lectin domain of DC-SIGN and prevents pathogen interaction through the presence of Lewis x-type oligosaccharides. Surprisingly, this was specific for human milk, as formula, bovine or camel milk did not show any presence of proteins that interacted with DC-SIGN. The expression of DC-SIGN is found in young infants along the entire gastrointestinal tract. Our data thus suggest the importance of human milk glycoproteins for blocking pathogen interaction to DC in young children. Moreover, a potential benefit of human milk later in life in shaping the infants immune system through DC-SIGN cannot be ruled out. PMID:25821450

  11. Identity of the elusive IgM Fc receptor (FcμR) in humans

    PubMed Central

    Oka, Satoshi; Kubagawa, Yoshiki; Torii, Ikuko; Takayama, Eiji; Kang, Dong-Won; Gartland, G. Larry; Bertoli, Luigi F.; Mori, Hiromi; Takatsu, Hiroyuki; Kitamura, Toshio; Ohno, Hiroshi; Wang, Ji-Yang

    2009-01-01

    Although Fc receptors (FcRs) for switched immunoglobulin (Ig) isotypes have been extensively characterized, FcR for IgM (FcμR) has defied identification. By retroviral expression and functional cloning, we have identified a complementary DNA (cDNA) encoding a bona fide FcμR in human B-lineage cDNA libraries. FcμR is defined as a transmembrane sialoglycoprotein of ∼60 kD, which contains an extracellular Ig-like domain homologous to two other IgM-binding receptors (polymeric Ig receptor and Fcα/μR) but exhibits an exclusive Fcμ-binding specificity. The cytoplasmic tail of FcμR contains conserved Ser and Tyr residues, but none of the Tyr residues match the immunoreceptor tyrosine-based activation, inhibitory, or switch motifs. Unlike other FcRs, the major cell types expressing FcμR are adaptive immune cells, including B and T lymphocytes. After antigen-receptor ligation or phorbol myristate acetate stimulation, FcμR expression was up-regulated on B cells but was down-modulated on T cells, suggesting differential regulation of FcμR expression during B and T cell activation. Although this receptor was initially designated as Fas apoptotic inhibitory molecule 3, or TOSO, our results indicate that FcμR per se has no inhibitory activity in Fas-mediated apoptosis and that such inhibition is only achieved when anti-Fas antibody of an IgM but not IgG isotype is used for inducing apoptosis. PMID:19858324

  12. Upregulation of miR-150* and miR-630 Induces Apoptosis in Pancreatic Cancer Cells by Targeting IGF-1R

    PubMed Central

    Farhana, Lulu; Dawson, Marcia I.; Murshed, Farhan; Das, Jayanta K.; Rishi, Arun K.; Fontana, Joseph A.

    2013-01-01

    MicroRNAs have been implicated in many critical cellular processes including apoptosis. We have previously found that apoptosis in pancreatic cancer cells was induced by adamantyl retinoid-related (ARR) molecule 3-Cl-AHPC. Here we report that 3-Cl-AHPC-dependent apoptosis involves regulating a number of microRNAs including miR-150* and miR-630. 3-Cl-AHPC stimulated miR-150* expression and caused decreased expression of c-Myb and IGF-1R in the pancreatic cancer cells. 3-Cl-AHPC-mediated reduction of c-Myb resulted in diminished binding of c-Myb with IGF-1R and Bcl-2 promoters, thereby causing repression of their transcription and protein expression. Over-expression of miR-150* also resulted in diminished levels of c-Myb and Bcl-2 proteins. Furthermore, the addition of the miRNA inhibitor 2′-O-methylated miR-150 blocked 3-Cl-AHPC-mediated increase in miR-150* levels and abrogated loss of c-Myb protein. Knockdown of c-Myb in PANC-1 cells resulted in enhanced apoptosis both in the presence or absence of 3-Cl-AHPC confirming the anti-apoptotic property of c-Myb. Overexpression of miR-630 also induced apoptosis in the pancreatic cancer cells and inhibited target protein IGF-1R mRNA and protein expression. Together these results implicate key roles for miR-150* and miR-630 and their targeting of IGF-1R to promote apoptosis in pancreatic cancer cells. PMID:23675407

  13. Shape-Engineering of Self-Assembled Organic Single Microcrystal as Optical Microresonator for laser Applications

    PubMed Central

    Wang, Xuedong; Liao, Qing; Lu, Xiaomei; Li, Hui; Xu, Zhenzhen; Fu, Hongbing

    2014-01-01

    Single micro/nanocrystals based on π-conjugated organic molecules have caused tremendous interests in the optoelectronic applications in laser, optical waveguide, nonlinear optics, and field effect transistors. However, the controlled synthesis of these organic micro/nanocrystals with regular shapes is very difficult to achieve, because the weak interaction (van der Waals' force, ca. 5 kJ/mol) between organic molecules could not dominate the kinetic process of crystal growth. Herein, we develop an elaborate strategy, selective adhesion to organic crystal plane by the hydrogen-bonding interaction (ca. 40 kJ/mol), for modulating the kinetic process of the formation of microcrystal, which leads to the self-assembly of one organic molecule 3-[4-(dimethylamino)phenyl]-1-(2-hy-droxyphenyl)prop-2-en-1-on (HDMAC) into one-dimensional (1D) microwires and 2D microdisks respectively. Furthermore, these as-prepared microcrystals demonstrate shape-dependent microresonator properties that 1D microwires act as Fabry-Pérot (FP) mode lasing resonator and 2D microdisks provide the whispering-gallery-mode (WGM) resonator for lasing oscillator. More significantly, through the investigation of the size-effect on the laser performance, single-mode lasing at red wavelength was successfully achieved in the self-assembled 2D organic microdisk at room temperature. These easily fabricated organic single-crystalline microcrystals with controlled shapes are the natural laser sources, which offer considerable promise for the multi-functionalities of coherent light devices integrated on the optics microchip. PMID:25388213

  14. The Porphobilinogen Conundrum in Prebiotic Routes to Tetrapyrrole Macrocycles

    NASA Astrophysics Data System (ADS)

    Taniguchi, Masahiko; Ptaszek, Marcin; Chandrashaker, Vanampally; Lindsey, Jonathan S.

    2016-05-01

    Attempts to develop a credible prebiotic route to tetrapyrroles have relied on enzyme-free recapitulation of the extant biosynthesis, but this process has foundered from the inability to form the pyrrole porphobilinogen (PBG) in good yield by self-condensation of the precursor δ-aminolevulinic acid (ALA). PBG undergoes robust oligomerization in aqueous solution to give uroporphyrinogen (4 isomers) in good yield. ALA, PBG, and uroporphyrinogen III are universal precursors to all known tetrapyrrole macrocycles. The enzymic formation of PBG entails carbon-carbon bond formation between the less stable enolate/enamine of one ALA molecule (3-position) and the carbonyl/imine (4-position) of the second ALA molecule; without enzymes, the first ALA reacts at the more stable enolate/enamine (5-position) and gives the pyrrole pseudo-PBG. pseudo-PBG cannot self-condense, yet has one open α-pyrrole position and is proposed to be a terminator of oligopyrromethane chain-growth from PBG. Here, 23 analogues of ALA have been subjected to density functional theoretical (DFT) calculations, but no motif has been identified that directs reaction at the 3-position. Deuteriation experiments suggested 5-(phosphonooxy)levulinic acid would react preferentially at the 3- versus 5-position, but a hybrid condensation with ALA gave no observable uroporphyrin. The results suggest efforts toward a biomimetic, enzyme-free route to tetrapyrroles from ALA should turn away from structure-directed reactions and focus on catalysts that orient the two aminoketones to form PBG in a kinetically controlled process, thereby avoiding formation of pseudo-PBG.

  15. The pathogenesis of tropical spastic paraparesis/human T-cell leukemia type I-associated myelopathy.

    PubMed

    Casseb, J; Penalva-de-Oliveira, A C

    2000-12-01

    Tropical spastic paraparesis/human T-cell leukemia type I-associated myelopathy (TSP/HAM) is caused by a human T-cell leukemia virus type I (HTLV-I) after a long incubation period. TSP/HAM is characterized by a chronic progressive paraparesis with sphincter disturbances, no/mild sensory loss, the absence of spinal cord compression and seropositivity for HTLV-I antibodies. The pathogenesis of this entity is not completely known and involves a multivariable phenomenon of immune system activation against the presence of HTLV-I antigens, leading to an inflammatory process and demyelination, mainly in the thoracic spinal cord. The current hypothesis about the pathogenesis of TSP/HAM is: 1) presence of HTLV-I antigens in the lumbar spinal cord, noted by an increased DNA HTLV-I load; 2) CTL either with their lytic functions or release/production of soluble factors, such as CC-chemokines, cytokines, and adhesion molecules; 3) the presence of Tax gene expression that activates T-cell proliferation or induces an inflammatory process in the spinal cord; 4) the presence of B cells with neutralizing antibody production, or complement activation by an immune complex phenomenon, and 5) lower IL-2 and IFN-gamma production and increased IL-10, indicating drive to a cytokine type 2 pattern in the TSP/HAM subjects and the existence of a genetic background such as some HLA haplotypes. All of these factors should be implicated in TSP/HAM and further studies are necessary to investigate their role in the development of TSP/HAM. PMID:11105090

  16. Human Cytomegalovirus Entry into Dendritic Cells Occurs via a Macropinocytosis-Like Pathway in a pH-Independent and Cholesterol-Dependent Manner

    PubMed Central

    Haspot, Fabienne; Lavault, Amélie; Sinzger, Christian; Laib Sampaio, Kerstin; Stierhof, York-Dieter; Pilet, Paul; Bressolette-Bodin, Céline; Halary, Franck

    2012-01-01

    Human cytomegalovirus (HCMV) is a ubiquitous herpesvirus that is able to infect fibroblastic, epithelial, endothelial and hematopoietic cells. Over the past ten years, several groups have provided direct evidence that dendritic cells (DCs) fully support the HCMV lytic cycle. We previously demonstrated that the C-type lectin dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) has a prominent role in the docking of HCMV on monocyte-derived DCs (MDDCs). The DC-SIGN/HCMV interaction was demonstrated to be a crucial and early event that substantially enhanced infection in trans, i.e., from one CMV-bearing cell to another non-infected cell (or trans-infection), and rendered susceptible cells fully permissive to HCMV infection. Nevertheless, nothing is yet known about how HCMV enters MDDCs. In this study, we demonstrated that VHL/E HCMV virions (an endothelio/dendrotropic strain) are first internalized into MDDCs by a macropinocytosis-like process in an actin- and cholesterol-dependent, but pH-independent, manner. We observed the accumulation of virions in large uncoated vesicles with endosomal features, and the virions remained as intact particles that retained infectious potential for several hours. This trans-infection property was specific to MDDCs because monocyte-derived macrophages or monocytes from the same donor were unable to allow the accumulation of and the subsequent transmission of the virus. Together, these data allowed us to delineate the early mechanisms of the internalization and entry of an endothelio/dendrotropic HCMV strain into human MDDCs and to propose that DCs can serve as a "Trojan horse" to convey CMV from entry sites to other locations that may favor the occurrence of either latency or acute infection. PMID:22496863

  17. 19F Magic angle spinning NMR reporter molecules: empirical measures of surface shielding, polarisability and H-bonding.

    PubMed

    Budarin, Vitaliy L; Clark, James H; Deswarte, Fabien E I; Mueller, Karl T; Tavener, Stewart J

    2007-06-14

    Magic Angle Spinning (MAS) (19)F NMR spectra have been obtained and chemical shifts measured for 37 molecules in the gas phase and adsorbed on the surfaces of six common materials: octadecyl- and octyl-functionalised chromatography silicas, Kieselgel 100 silica, Brockmann neutral alumina, Norit activated charcoal and 3-(1-piperidino)propyl functionalised silica. From these six surfaces, octadecyl-silica is selected as a non-polar reference to which the others are compared. The change in chemical shift of a fluorine nucleus within a molecule on adsorption to a surface from the gas phase, Deltadelta(gas)(surface), is described by the empirical relationship: Deltadelta(gas)(surface) = delta(s) + (alpha(s)+pi(s))/alpha(r) (Deltadelta(gas)(reference) - delta(r)) + delta(HBA) + delta(HBD), where delta(s) and delta(r) are constants that describe the chemical shift induced by the electromagnetic field of the surface under investigation and reference surface, alpha(s) and alpha(r) are the relative surface polarisability for the surface and reference, pi(s) is an additional contribution to the surface polarisabilities due to its ability to interact with aromatic molecules, and delta(HBA) and delta(HBD) are measurements of the hydrogen acceptor and donor properties of the surface. These empirical parameters are measured for the surfaces under study. Silica and alumina are found to undergo specific interactions with aromatic reporter molecules and both accept and donate H-bonds. Activated charcoal was found to have an extreme effect on shielding but no specific interactions with the adsorbed molecules. 3-(1-Piperidino)propyl functionalised silica exhibits H-bond acceptor ability, but does not donate H-bonds. PMID:17487325

  18. An Improved Optical Model for the Non-LTE Problem for the CO2 Molecule in the Atmosphere of Mars: Nighttime Populations of Vibrational States and the Rate of Radiative Cooling of the Atmosphere

    NASA Astrophysics Data System (ADS)

    Ogibalov, V. P.; Shved, G. M.

    2003-01-01

    The estimates of the population of excited vibrational states of the CO2 molecule and of the rate of radiative cooling of the atmosphere in the 15-μm CO2 band are given for the nighttime mesosphere and thermosphere of Mars. For the first time, these estimates are made (1) with allowance for the overlap of lines in the 15-μm band; (2) for a wide set of vibrational states of seven isotopes of the CO2 molecule, which was used earlier in the solution of a similar terrestrial problem; and (3) using the rate constant for quenching of the CO2(0110) state in collisions with oxygen atoms, which has been recently measured for low temperatures by Khvorostovskaya et al. (2002). The main results are as follows. 1. The approximation of isolated lines provides a satisfactory accuracy of determining the radiative cooling rate and overestimates vibrational temperatures of the states of the ν2 mode by no more than 3 K for the 12C16O2 molecule and by no more than 2 K for low-abundant isotopes of the CO2 molecule. 2. A reasonably high accuracy of estimating the cooling rate can be achieved by taking into account only fundamental vibrational transitions in 12C16O2, 13C16O2, 16O12C18O, and 16O12C17O molecules and the hot transitions 2ν2 --> ν2 and 3ν2 --> 2ν2 in the 12C16O2 molecule. 3. The vertical profile of the total rate of radiative cooling displays two peaks. The maximum near a height of 130 km is very sensitive to temperature and to the ratio of the mixture for oxygen in the atmosphere.

  19. Characterization and expression of human bifunctional 3'-phosphoadenosine 5'-phosphosulphate synthase isoforms.

    PubMed Central

    Fuda, Hirotoshi; Shimizu, Chikara; Lee, Young C; Akita, Harukuni; Strott, Charles A

    2002-01-01

    Sulphonation, a fundamental process essential for normal growth and development, requires the sulphonate donor molecule 3'-phosphoadenosine 5'-phosphosulphate (PAPS), which is produced from ATP and inorganic sulphate by the bifunctional enzyme PAPS synthase. In humans, two genes encode isoenzymes that are 77% identical at the amino acid level, and alternative splicing creates two subtypes of PAPS synthase 2. The question as to whether distinctions in amino acid composition are reflected in differences in activity has been examined. The specific activity of the PAPS synthase 2 subtypes is 10- to 15-fold higher than that for PAPS synthase 1. The greater catalytic efficiency of the PAPS synthase 2 subtypes is demonstrated further by the 3- to 6-fold higher k(cat)/K(m) ratios for ATP and inorganic sulphate as compared with the ratios for PAPS synthase 1. In humans, PAPS synthase 1 is expressed ubiquitously, and is the dominant isoform in most tissues, whereas expression of the PAPS synthase 2 subtypes is variable and tissue-specific. It is noteworthy that, similar to other human tissues, PAPS synthase 1 also appears to be the dominant isoform expressed in cartilage. The latter finding initially created a conundrum, since there is a specific human dwarfing disorder that is known to be caused by a mutation in the PAPS synthase 2 gene. This apparent enigma would seem to be resolved by examination of cartilage from guinea-pigs as an animal model. Similar to humans, cartilage from mature animals predominantly expresses PAPS synthase 1. In contrast, expression of PAPS synthase 1 is relatively low in the cartilage of immature guinea-pigs, including the growth plate of long bones, whereas PAPS synthase 2 is the highly expressed isoenzyme. PMID:11931637

  20. N-Glycans on the Rift Valley Fever Virus Envelope Glycoproteins Gn and Gc Redundantly Support Viral Infection via DC-SIGN

    PubMed Central

    Phoenix, Inaia; Nishiyama, Shoko; Lokugamage, Nandadeva; Hill, Terence E.; Huante, Matthew B.; Slack, Olga A.L.; Carpio, Victor H.; Freiberg, Alexander N.; Ikegami, Tetsuro

    2016-01-01

    Rift Valley fever is a mosquito-transmitted, zoonotic disease that infects humans and ruminants. Dendritic cell specific intercellular adhesion molecule 3 (ICAM-3) grabbing non-integrin (DC-SIGN) acts as a receptor for members of the phlebovirus genus. The Rift Valley fever virus (RVFV) glycoproteins (Gn/Gc) encode five putative N-glycan sequons (asparagine (N)–any amino acid (X)–serine (S)/threonine (T)) at positions: N438 (Gn), and N794, N829, N1035, and N1077 (Gc). The N-glycosylation profile and significance in viral infection via DC-SIGN have not been elucidated. Gc N-glycosylation was first evaluated by using Gc asparagine (N) to glutamine (Q) mutants. Subsequently, we generated a series of recombinant RVFV MP-12 strain mutants, which encode N-to-Q mutations, and the infectivity of each mutant in Jurkat cells stably expressing DC-SIGN was evaluated. Results showed that Gc N794, N1035, and N1077 were N-glycosylated but N829 was not. Gc N1077 was heterogeneously N-glycosylated. RVFV Gc made two distinct N-glycoforms: “Gc-large” and “Gc-small”, and N1077 was responsible for “Gc-large” band. RVFV showed increased infection of cells expressing DC-SIGN compared to cells lacking DC-SIGN. Infection via DC-SIGN was increased in the presence of either Gn N438 or Gc N1077. Our study showed that N-glycans on the Gc and Gn surface glycoproteins redundantly support RVFV infection via DC-SIGN. PMID:27223297

  1. Matrix molecularly imprinted mesoporous sol-gel sorbent for efficient solid-phase extraction of chloramphenicol from milk.

    PubMed

    Samanidou, Victoria; Kehagia, Maria; Kabir, Abuzar; Furton, Kenneth G

    2016-03-31

    Highly selective and efficient chloramphenicol imprinted sol-gel silica based inorganic polymeric sorbent (sol-gel MIP) was synthesized via matrix imprinting approach for the extraction of chloramphenicol in milk. Chloramphenicol was used as the template molecule, 3-aminopropyltriethoxysilane (3-APTES) and triethoxyphenylsilane (TEPS) as the functional precursors, tetramethyl orthosilicate (TMOS) as the cross-linker, isopropanol as the solvent/porogen, and HCl as the sol-gel catalyst. Non-imprinted sol-gel polymer (sol-gel NIP) was synthesized under identical conditions in absence of template molecules for comparison purpose. Both synthesized materials were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and nitrogen adsorption porosimetry, which unambiguously confirmed their significant structural and morphological differences. The synthesized MIP and NIP materials were evaluated as sorbents for molecularly imprinted solid phase extraction (MISPE) of chloramphenicol in milk. The effect of critical extraction parameters (flow rate, elution solvent, sample and eluent volume, selectivity coefficient, retention capacity) was studied in terms of retention and desorption of chloramphenicol. Competition and cross reactivity tests have proved that sol-gel MIP sorbent possesses significantly higher specific retention and enrichment capacity for chloramphenicol compared to its non-imprinted analogue. The maximum imprinting factor (IF) was found as 9.7, whereas the highest adsorption capacity of chloramphenicol by sol-gel MIP was 23 mg/g. The sol-gel MIP was found to be adequately selective towards chloramphenicol to provide the necessary minimum required performance limit (MRPL) of 0.3 μg/kg set forth by European Commission after analysis by LC-MS even without requiring time consuming solvent evaporation and sample reconstitution step, often considered as an integral part in solid phase extraction work-flow. Intra and

  2. Cholinergic neurotransmission links solitary chemosensory cells to nasal inflammation

    PubMed Central

    Saunders, Cecil J.; Christensen, Michael; Finger, Thomas E.; Tizzano, Marco

    2014-01-01

    Solitary chemosensory cells (SCCs) of the nasal cavity are specialized epithelial chemosensors that respond to irritants through the canonical taste transduction cascade involving Gα-gustducin and transient receptor potential melastatin 5. When stimulated, SCCs trigger peptidergic nociceptive (or pain) nerve fibers, causing an alteration of the respiratory rate indicative of trigeminal activation. Direct chemical excitation of trigeminal pain fibers by capsaicin evokes neurogenic inflammation in the surrounding epithelium. In the current study, we test whether activation of nasal SCCs can trigger similar local inflammatory responses, specifically mast cell degranulation and plasma leakage. The prototypical bitter compound, denatonium, a well-established activator of SCCs, caused significant inflammatory responses in WT mice but not mice with a genetic deletion of elements of the canonical taste transduction cascade, showing that activation of taste signaling components is sufficient to trigger local inflammation. Chemical ablation of peptidergic trigeminal fibers prevented the SCC-induced nasal inflammation, indicating that SCCs evoke inflammation only by neural activity and not by release of local inflammatory mediators. Additionally, blocking nicotinic, but not muscarinic, acetylcholine receptors prevents SCC-mediated neurogenic inflammation for both denatonium and the bacterial signaling molecule 3-oxo-C12-homoserine lactone, showing the necessity for cholinergic transmission. Finally, we show that the neurokinin 1 receptor for substance P is required for SCC-mediated inflammation, suggesting that release of substance P from nerve fibers triggers the inflammatory events. Taken together, these results show that SCCs use cholinergic neurotransmission to trigger peptidergic trigeminal nociceptors, which link SCCs to the neurogenic inflammatory pathway. PMID:24711432

  3. Sieving characteristics of cytokine- and peroxide-induced epithelial barrier leak: Inhibition by berberine

    PubMed Central

    DiGuilio, Katherine M; Mercogliano, Christina M; Born, Jillian; Ferraro, Brendan; To, Julie; Mixson, Brittany; Smith, Allison; Valenzano, Mary Carmen; Mullin, James M

    2016-01-01

    AIM: To study whether the inflammatory bowel disease (IBD) colon which exhibits varying severity and cytokine levels across its mucosa create varying types of transepithelial leak. METHODS: We examined the effects of tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-1-β (IL1β) and hydrogen peroxide (H2O2) - singly and in combinations - on barrier function of CACO-2 cell layers. Our focus was on the type (not simply the magnitude) of transepithelial leak generated by these agents as measured by transepithelial electrical resistance (TER) and transepithelial flux of 14C-D-mannitol, 3H-Lactulose and 14C-Polyethylene glycol as radiolabeled probe molecules. The isoquinoline alkaloid, berberine, was then examined for its ability to reduce specific types of transepithelial leak. RESULTS: Exposure to TNF-α alone (200 ng/mL; 48 h) induced a 50% decrease in TER, i.e., increased leak of Na+ and Cl- - with only a marginal but statistically significant increase in transepithelial leak of 14C-mannitol (Jm). Exposure to TNF-α + IFN-γ (200 ng/mL; 48 h) + IL1β (50 ng/mL; 48 h) did not increase the TER change (from TNF-α alone), but there was now a 100% increase in Jm. There however was no increase in transepithelial leak of two larger probe molecules, 3H-lactulose and 14C-polyethylene glycol (PEG). However, exposure to TNF-α + IFN-γ + IL1β followed by a 5 h exposure to 2 mmol/L H2O2 resulted in a 500% increase in 14C-PEG leak as well as leak to the luminal mitogen, epidermal growth factor. CONCLUSION: This model of graded transepithelial leak is useful in evaluating therapeutic agents reducing IBD morbidity by reducing barrier leak to various luminal substances. PMID:27190695

  4. Nanostructured Inverted Organic Photovoltaic Cells

    NASA Astrophysics Data System (ADS)

    Thomas, Michael

    Organic photovoltaic cells (OPVs)are promising devices for inexpensive power generation from sunlight. Organic semiconductors, the basic materials for OPVs, can be fabricated using a broad range of fabrication technologies from vapor deposition to solution processing. Upon light absorption, a strongly bound exciton is generated which can diffuse to a donor-acceptor heterojunction. At this interface it can be dissociated into free charge carriers which can be collected by the device electrodes. A major challenge for OPVs are short exciton diffusion lengths of up to 20 nm. Morphology engineering is required in order to harvest the exciton before it recombines and improve OPV performance. This work focuses on the study of nanostructured morphologies for use in inverted architecture OPVs. Glancing angle deposition (GLAD)is employed to fabricate nanocolumnar acceptor films. Through combining these nanostructured C60 films with a conjugated polymer donor P3CBT and a small molecule 3-Q, inverted OPVs are fabricated with the goal to analyze effect of morphology engineering on device performance. A major challenge was that C60 were found to be soluble in most commonly used organic solvents such as dichlorobenzene or chloroform. Although this challenge has limited the donor choice and therefore has limited device performance, a significant effect of morphology engineering could be observed. All GLAD structured C60 OPVs outperformed state of the art architectures such as planar films and bulk heterojunctions fabricated with the same materials. For P3CBT in particular the GLAD structured devices exhibited a twofold increase in power conversion efficiency compared with bulk heterojunctions and a fourfold increase compared with planar devices. In a further study, the acceptor materials PTCDA and C60 were co-evaporated into a single film. PTCDA is stable against non-polar organic solvents while C60 provides a high electron mobility. Nanocolumnar acceptor blended PTCDA:C60 films

  5. Synthesis, superoxide dismutase, nuclease, and anticancer activities of copper(II) complexes incorporating bis(2-picolyl)amine with different counter anions

    NASA Astrophysics Data System (ADS)

    Ibrahim, Mohamed M.; Ramadan, Abdel-Motaleb M.; Mersal, Gaber A. M.; El-Shazly, Samir A.

    2011-07-01

    Interaction of the tridentate ligand bis(2-picolyl)amine L with copper(II) salts gave a series of copper(II) complexes with the formula types: [ LCu(X) 2] (X = Cl -1, = Br -2), [( LCu (H 2O)(μ-SO 4)( LCu(H 2O)]SO 43, [ LCu(OAc)](OAc )H 2O 4, [ LCu(H 2O) 2](Y) 2 (Y = NO3-5, = ClO4-6). Their structures and properties were characterized by elemental analysis, thermal analysis (TGA), IR, UV-vis and ESR spectroscopy, electrochemical measurements including cyclic voltammetry and electrical molar conductivity, and magnetic moment measurements. A square pyramidal geometry is proposed for the halogeno complexes 1 and 2 in monomeric structures. For sulfate complex, the sulfate group bridged two copper(II) ions of the two [N 3O] donor units to give the dimeric complex molecule 3 in square pyramidal environment around the copper(II) ions. In the case of complexes 4- 6, square planar stereochemistries in monomeric structures are suggested. The SOD biomimetic catalytic activity of the obtained complexes was assessed for their ability to inhibit the reduction of nitroblue tetrazolium (NBT). The catalytic efficiency of O2- scavenging by complexes depends on the nature of the particular acidic anion radical incorporated in the complex molecule and follows the order: NO3- > ClO4- > Br - ⩾ Cl - > SO4- > AcO -. A probable mechanistic implications for the catalytic dismutation of O2- by copper(II) complexes are proposed. Furthermore, complex 1 exhibits significant hydrolytic cleavage of the genomic DNA in the absence of any external additives. In addition, the in vitro study of cytotoxicity of complex 1 on colon cancer cell line (Caco-2) indicates that the complex has the potential to act as an effective anticancer drug with IC 50 value of 156 ± 0.35 μM.

  6. A chalcone-related small molecule that induces methuosis, a novel form of non-apoptotic cell death, in glioblastoma cells

    PubMed Central

    2011-01-01

    Background Methuosis is a unique form of non-apoptotic cell death triggered by alterations in the trafficking of clathrin-independent endosomes, ultimately leading to extreme vacuolization and rupture of the cell. Results Here we describe a novel chalcone-like molecule, 3-(2-methyl-1H- indol-3-yl)-1-(4-pyridinyl)-2-propen-1-one (MIPP) that induces cell death with the hallmarks of methuosis. MIPP causes rapid accumulation of vacuoles derived from macropinosomes, based on time-lapse microscopy and labeling with extracellular fluid phase tracers. Vacuolization can be blocked by the cholesterol-interacting compound, filipin, consistent with the origin of the vacuoles from non-clathrin endocytic compartments. Although the vacuoles rapidly acquire some characteristics of late endosomes (Rab7, LAMP1), they remain distinct from lysosomal and autophagosomal compartments, suggestive of a block at the late endosome/lysosome boundary. MIPP appears to target steps in the endosomal trafficking pathway involving Rab5 and Rab7, as evidenced by changes in the activation states of these GTPases. These effects are specific, as other GTPases (Rac1, Arf6) are unaffected by the compound. Cells treated with MIPP lose viability within 2-3 days, but their nuclei show no evidence of apoptotic changes. Inhibition of caspase activity does not protect the cells, consistent with a non-apoptotic death mechanism. U251 glioblastoma cells selected for temozolomide resistance showed sensitivity to MIPP-induced methuosis that was comparable to the parental cell line. Conclusions MIPP might serve as a prototype for new drugs that could be used to induce non-apoptotic death in cancers that have become refractory to agents that work through DNA damage and apoptotic mechanisms. PMID:21639944

  7. Dermal CD14(+) Dendritic Cell and Macrophage Infection by Dengue Virus Is Stimulated by Interleukin-4.

    PubMed

    Schaeffer, Evelyne; Flacher, Vincent; Papageorgiou, Vasiliki; Decossas, Marion; Fauny, Jean-Daniel; Krämer, Melanie; Mueller, Christopher G

    2015-07-01

    Dengue virus (DENV) is responsible for the most prevalent arthropod-borne viral infection in humans. Events decisive for disease development occur in the skin after virus inoculation by the mosquito. Yet, the role of human dermis-resident immune cells in dengue infection and disease remains elusive. Here we investigated how dermal dendritic cells (dDCs) and macrophages (dMs) react to DENV and impact on immunopathology. We show that both CD1c(+) and CD14(+) dDC subsets were infected, but viral load greatly increased in CD14(+) dDCs upon IL-4 stimulation, which correlated with upregulation of virus-binding lectins Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Nonintegrin (DC-SIGN/CD209) and mannose receptor (CD206). IL-4 also enhanced T-cell activation by dDCs, which was further increased upon dengue infection. dMs purified from digested dermis were initially poorly infected but actively replicated the virus and produced TNF-α upon lectin upregulation in response to IL-4. DC-SIGN(+) cells are abundant in inflammatory skin with scabies infection or Th2-type dermatitis, suggesting that skin reactions to mosquito bites heighten the risk of infection and subsequent immunopathology. Our data identify dDCs and dMs as primary arbovirus target cells in humans and suggest that dDCs initiate a potent virus-directed T-cell response, whereas dMs fuel the inflammatory cascade characteristic of dengue fever. PMID:25521455

  8. Magnetic moment enhancement and spin polarization switch of the manganese phthalocyanine molecule on an IrMn(100) surface

    SciTech Connect

    Sun, X.; Wang, B.; Pratt, A.; Yamauchi, Y.

    2014-07-21

    The geometric, electronic, and magnetic structures of a manganese phthalocyanine (MnPc) molecule on an antiferromagnetic IrMn(100) surface are studied by density functional theory calculations. Two kinds of orientation of the adsorbed MnPc molecule are predicted to coexist due to molecular self-assembly on the surface—a top-site geometry with the Mn–N bonds aligned along the 〈100〉 direction, and a hollow-site orientation in which the Mn–N bonds are parallel to the 〈110〉 direction. The MnPc molecule is antiferromagnetically coupled to the substrate at the top site with a slight reduction in the magnetic moment of the Mn atom of the MnPc molecule (Mn{sub mol}). In contrast, the magnetic moment of the Mn{sub mol} is enhanced to 4.28 μB at the hollow site, a value larger than that in the free MnPc molecule (3.51 μB). Molecular distortion induced by adsorption is revealed to be responsible for the enhancement of the magnetic moment. Furthermore, the spin polarization of the Mn{sub mol} atom at around the Fermi level is found to change from negative to positive through an elongation of the Mn–N bonds of the MnPc. We propose that a reversible switch of the low/high magnetic moment and negative/positive spin polarization might be realized through some mechanical engineering methods.

  9. Simple Analytic Collisional Rates for non-LTE Vibrational Populations in Astrophysical Environments: the Cases of Circumstellar SiO Masers and Shocked H2

    NASA Astrophysics Data System (ADS)

    Bieniek, Ronald

    2008-05-01

    Rates for collisionally induced transitions between molecular vibrational levels are important in modeling a variety of non-LTE processes in astrophysical environments. Two examples are SiO masering in circumstellar envelopes in certain late-type stars [1] and the vibrational populations of molecular hydrogen in shocked interstellar medium [cf 2]. A simple exponential-potential model of molecular collisions leads to a two-parameter analytic expression for state-to-state and thermally averaged rates for collisionally induced vibrational-translational (VT) transitions in diatomic molecules [3,4]. The thermally averaged rates predicted by this formula have been shown to be in excellent numerical agreement with absolute experimental and quantum mechanical rates over large temperature ranges and initial vibrational excitation levels in a variety of species, e.g., OH, O2, N2 [3] and even for the rate of H2(v=1)+H2, which changes by five orders of magnitude in the temperature range 50-2000 K [4]. Analogous analytic rates will be reported for vibrational transitions in SiO due to collisions with H2 and compared to the numerical fit of quantum-mechanical rates calculated by Bieniek and Green [5]. [1] Palov, A.P., Gray, M.D., Field, D., & Balint-Kurti, G.G. 2006, ApJ, 639, 204. [2] Flower, D. 2007, Molecular Collisions in the Interstellar Medium (Cambridge: Cambridge Univ. Press) [3] Bieniek, R.J. & Lipson, S.J. 1996, Chem. Phys. Lett. 263, 276. [4] Bieniek, R.J. 2006, Proc. NASA LAW (Lab. Astrophys. Workshop) 2006, 299; http://www.physics.unlv.edu/labastro/nasalaw2006proceedings.pdf. [5] Bieniek, R.J., & Green, S. 1983, ApJ, 265, L29 and 1983, ApJ, 270, L101.

  10. Engineering Graphene Conductivity for Flexible and High-Frequency Applications.

    PubMed

    Samuels, Alexander J; Carey, J David

    2015-10-14

    Advances in lightweight, flexible, and conformal electronic devices depend on materials that exhibit high electrical conductivity coupled with high mechanical strength. Defect-free graphene is one such material that satisfies both these requirements and which offers a range of attractive and tunable electrical, optoelectronic, and plasmonic characteristics for devices that operate at microwave, terahertz, infrared, or optical frequencies. Essential to the future success of such devices is therefore the ability to control the frequency-dependent conductivity of graphene. Looking to accelerate the development of high-frequency applications of graphene, here we demonstrate how readily accessible and processable organic and organometallic molecules can efficiently dope graphene to carrier densities in excess of 10(13) cm(-2) with conductivities at gigahertz frequencies in excess of 60 mS. In using the molecule 3,6-difluoro-2,5,7,7,8,8-hexacyanoquinodimethane (F2-HCNQ), a high charge transfer (CT) of 0.5 electrons per adsorbed molecule is calculated, resulting in p-type doping of graphene. n-Type doping is achieved using cobaltocene and the sulfur-containing molecule tetrathiafulvalene (TTF) with a CT of 0.41 and 0.24 electrons donated per adsorbed molecule, respectively. Efficient CT is associated with the interaction between the π electrons present in the molecule and in graphene. Calculation of the high-frequency conductivity shows dispersion-less behavior of the real component of the conductivity over a wide range of gigahertz frequencies. Potential high-frequency applications in graphene antennas and communications that can exploit these properties and the broader impacts of using molecular doping to modify functional materials that possess a low-energy Dirac cone are also discussed. PMID:26387636

  11. GC/MIP/AED method for pesticide residue determination in fruits and vegetables.

    PubMed

    Ting, K C; Kho, P

    1991-01-01

    This research describes the results of a gas chromatography/microwave induced plasma/atomic emission detection (GC/MIP/AED) method performed on a Hewlett-Packard 5921A system for pesticide residue analysis in fruits and vegetables. A total of 6 experiments were conducted: (1) sensitivity and linearity studies for elements S, P, Cl, and N by analyzing dursban; (2) a study of instrument response to Cl concentration in pesticide molecules; (3) organochlorinated pesticide recoveries; (4) organophosphate pesticide recoveries; (5) carbamate pesticide recoveries; and (6) investigation of metallic pesticides with plictran and vendex as standards. The rank according to sensitivity and linearity was found to be as follows: S-181 greater than P-178 greater than Cl-479 greater than N-174. Instrument response to the concentration of chlorine atoms in the pesticide molecule was linear, with a correlation coefficient of 0.89. Recoveries of organochlorinated pesticides were 91.7-109.3%, with the exception of citrus, whose recovery was affected by coeluting interferences. Organophosphate recoveries were 73.2% or higher, except for the cygon oxygen analog, which degraded in the GC system under all circumstances. Carbamate recoveries were inconsistent quantitatively; however, the information generated from elements N and S were useful for qualitative confirmation of other methods, such as LC postcolumn derivatization analysis. Overall, the GC/MIP/AED method is powerful for qualitative confirmation in pesticide residue analysis. The instrument's capability of acquiring multi-elements (Cl and P) selectively and accurately is an alternative method for organochlorinated and organophosphate pesticide residue analyses. In addition, the GC/MIP/AED system is easy to use, simple to maintain, and its chromatograms can be interpreted by any chromatography analyst without much prior training. PMID:1757425

  12. A translational study "case report" on the small molecule "energy blocker" 3-bromopyruvate (3BP) as a potent anticancer agent: from bench side to bedside.

    PubMed

    Ko, Y H; Verhoeven, H A; Lee, M J; Corbin, D J; Vogl, T J; Pedersen, P L

    2012-02-01

    The small alkylating molecule, 3-bromopyruvate (3BP), is a potent and specific anticancer agent. 3BP is different in its action from most currently available chemo-drugs. Thus, 3BP targets cancer cells' energy metabolism, both its high glycolysis ("Warburg Effect") and mitochondrial oxidative phosphorylation. This inhibits/ blocks total energy production leading to a depletion of energy reserves. Moreover, 3BP as an "Energy Blocker", is very rapid in killing such cells. This is in sharp contrast to most commonly used anticancer agents that usually take longer to show a noticeable effect. In addition, 3BP at its effective concentrations that kill cancer cells has little or no effect on normal cells. Therefore, 3BP can be considered a member, perhaps one of the first, of a new class of anticancer agents. Following 3BP's discovery as a novel anticancer agent in vitro in the Year 2000 (Published in Ko et al. Can Lett 173:83-91, 2001), and also as a highly effective and rapid anticancer agent in vivo shortly thereafter (Ko et al. Biochem Biophys Res Commun 324:269-275, 2004), its efficacy as a potent anticancer agent in humans was demonstrated. Here, based on translational research, we report results of a case study in a young adult cancer patient with fibrolamellar hepatocellular carcinoma. Thus, a bench side discovery in the Department of Biological Chemistry at Johns Hopkins University, School of Medicine was taken effectively to bedside treatment at Johann Wolfgang Goethe University Frankfurt/Main Hospital, Germany. The results obtained hold promise for 3BP as a future cancer therapeutic without apparent cyto-toxicity when formulated properly. PMID:22328020

  13. N-Glycans on the Rift Valley Fever Virus Envelope Glycoproteins Gn and Gc Redundantly Support Viral Infection via DC-SIGN.

    PubMed

    Phoenix, Inaia; Nishiyama, Shoko; Lokugamage, Nandadeva; Hill, Terence E; Huante, Matthew B; Slack, Olga A L; Carpio, Victor H; Freiberg, Alexander N; Ikegami, Tetsuro

    2016-01-01

    Rift Valley fever is a mosquito-transmitted, zoonotic disease that infects humans and ruminants. Dendritic cell specific intercellular adhesion molecule 3 (ICAM-3) grabbing non-integrin (DC-SIGN) acts as a receptor for members of the phlebovirus genus. The Rift Valley fever virus (RVFV) glycoproteins (Gn/Gc) encode five putative N-glycan sequons (asparagine (N)-any amino acid (X)-serine (S)/threonine (T)) at positions: N438 (Gn), and N794, N829, N1035, and N1077 (Gc). The N-glycosylation profile and significance in viral infection via DC-SIGN have not been elucidated. Gc N-glycosylation was first evaluated by using Gc asparagine (N) to glutamine (Q) mutants. Subsequently, we generated a series of recombinant RVFV MP-12 strain mutants, which encode N-to-Q mutations, and the infectivity of each mutant in Jurkat cells stably expressing DC-SIGN was evaluated. Results showed that Gc N794, N1035, and N1077 were N-glycosylated but N829 was not. Gc N1077 was heterogeneously N-glycosylated. RVFV Gc made two distinct N-glycoforms: "Gc-large" and "Gc-small", and N1077 was responsible for "Gc-large" band. RVFV showed increased infection of cells expressing DC-SIGN compared to cells lacking DC-SIGN. Infection via DC-SIGN was increased in the presence of either Gn N438 or Gc N1077. Our study showed that N-glycans on the Gc and Gn surface glycoproteins redundantly support RVFV infection via DC-SIGN. PMID:27223297

  14. Human DC-SIGN binds specific human milk glycans.

    PubMed

    Noll, Alexander J; Yu, Ying; Lasanajak, Yi; Duska-McEwen, Geralyn; Buck, Rachael H; Smith, David F; Cummings, Richard D

    2016-05-15

    Human milk glycans (HMGs) are prebiotics, pathogen receptor decoys and regulators of host physiology and immune responses. Mechanistically, human lectins (glycan-binding proteins, hGBP) expressed by dendritic cells (DCs) are of major interest, as these cells directly contact HMGs. To explore such interactions, we screened many C-type lectins and sialic acid-binding immunoglobulin-like lectins (Siglecs) expressed by DCs for glycan binding on microarrays presenting over 200 HMGs. Unexpectedly, DC-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) showed robust binding to many HMGs, whereas other C-type lectins failed to bind, and Siglec-5 and Siglec-9 showed weak binding to a few glycans. By contrast, most hGBP bound to multiple glycans on other microarrays lacking HMGs. An α-linked fucose residue was characteristic of HMGs bound by DC-SIGN. Binding of DC-SIGN to the simple HMGs 2'-fucosyl-lactose (2'-FL) and 3-fucosyl-lactose (3-FL) was confirmed by flow cytometry to beads conjugated with 2'-FL or 3-FL, as well as the ability of the free glycans to inhibit DC-SIGN binding. 2'-FL had an IC50 of ∼1 mM for DC-SIGN, which is within the physiological concentration of 2'-FL in human milk. These results demonstrate that DC-SIGN among the many hGBP expressed by DCs binds to α-fucosylated HMGs, and suggest that such interactions may be important in influencing immune responses in the developing infant. PMID:26976925

  15. Janus Reversal and Coulomb Blockade in Ferrocene-Perylenebisimide and N,N,N',N'-Tetramethyl-para-phenylenediamine-Perylenebisimide D-σ-A Rectifiers.

    PubMed

    Johnson, Marcus S; Kota, Rajesh; Mattern, Daniell L; Metzger, Robert M

    2016-07-12

    Sandwiches "EGaIn|Ga2O3|LB monolayer of 2|Au" and "EGaIn|Ga2O3|LB monolayer of 3|Au" rectify. They are formed from a Langmuir-Blodgett (LB) monolayer of 2 or 3 transferred onto thermally evaporated gold. Molecules 2 and 3 are of the donor-sigma-acceptor (D-σ-A) type and have the same perylenebisimide (PBI) acceptor as previously studied molecule 1. Molecule 1 has the weak donor pyrene, 2 has the good donor ferrocene, and 3 has the very strong donor N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD). All three molecules have a long swallowtail ending in a thioacetyl group, which ensures slow chemisorption onto the Au electrode. These molecules were contacted directly by a gallium indium eutectic (EGaIn) drop, covered by a defective oxide Ga2O3 layer. As before for 1, the direction of rectification for 2 is bias-dependent. In the ±1.0 V range, the rectification is at positive V, with a rectification ratio (RR) that is initially greater than 5 and then decreases on successive scans to 2, while the currents decrease by as much as 2 orders of magnitude. In the ±2.5 V range, the rectification direction for 2 reverses, while upon repeated scanning the rectification ratio (in the negative direction) increases and the currents decrease. For molecule 3, both directions have a charge-trapped state (Coulomb blockade) leading to Voffset in both biases, but at high potentials rectification set is, with large RR (up to 2,800) at ±2.5 V. PMID:27238389

  16. The sequence of the CA-SP1 junction accounts for the differential sensitivity of HIV-1 and SIV to the small molecule maturation inhibitor 3-O-{3',3'-dimethylsuccinyl}-betulinic acid

    PubMed Central

    Zhou, Jing; Chen, Chin Ho; Aiken, Christopher

    2004-01-01

    Background Despite the effectiveness of currently available antiretroviral therapies in the treatment of HIV-1 infection, a continuing need exists for novel compounds that can be used in combination with existing drugs to slow the emergence of drug-resistant viruses. We previously reported that the small molecule 3-O-{3',3'-dimethylsuccinyl}-betulinic acid (DSB) specifically inhibits HIV-1 replication by delaying the processing of the CA-SP1 junction in Pr55Gag. By contrast, SIVmac239 replicates efficiently in the presence of high concentrations of DSB. To determine whether sequence differences in the CA-SP1 junction can fully account for the differential sensitivity of HIV-1 and SIV to DSB, we engineered mutations in this region of two viruses and tested their sensitivity to DSB in replication assays using activated human primary CD4+ T cells. Results Substitution of the P2 and P1 residues of HIV-1 by the corresponding amino acids of SIV resulted in strong resistance to DSB, but the mutant virus replicated with reduced efficiency. Conversely, replication of an SIV mutant containing three amino acid substitutions in the CA-SP1 cleavage site was highly sensitive to DSB, and the mutations resulted in delayed cleavage of the CA-SP1 junction in the presence of the drug. Conclusions These results demonstrate that the CA-SP1 junction in Pr55Gag represents the primary viral target of DSB. They further suggest that the therapeutic application of DSB will be accompanied by emergence of mutant viruses that are highly resistant to the drug but which exhibit reduced fitness relative to wild type HIV-1. PMID:15225375

  17. Lectin binding to surface Ig variable regions provides a universal persistent activating signal for follicular lymphoma cells.

    PubMed

    Linley, Adam; Krysov, Sergey; Ponzoni, Maurilio; Johnson, Peter W; Packham, Graham; Stevenson, Freda K

    2015-10-15

    The vast majority of cases of follicular lymphoma (FL), but not normal B cells, acquire N-glycosylation sites in the immunoglobulin variable regions during somatic hypermutation. Glycans added to sites are unusual in terminating at high mannoses. We showed previously that the C-type lectins, dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN) and mannose receptor, bound to FL surface immunoglobulin (sIg), generating an intracellular Ca(2+) flux. We have now mapped further intracellular pathways activated by DC-SIGN in a range of primary FL cells with detection of phosphorylated ERK1/2, AKT, and PLCγ2. The SYK inhibitor (tamatinib) or the BTK inhibitor (ibrutinib) each blocked phosphorylation. Activation by DC-SIGN occurred in both IgM(+) and IgG(+) cases and led to upregulation of MYC expression, with detection in vivo observed in lymph nodes. Unlike cells of chronic lymphocytic leukemia, FL cells expressed relatively high levels of sIg, unchanged by long-term incubation in vitro, indicating no antigen-mediated downregulation in vivo. In contrast, expression of CXCR4 increased in vitro. Engagement of sIg in FL cells or normal B cells by anti-Ig led to endocytosis in vitro as expected, but DC-SIGN, even when cross-linked, did not lead to significant endocytosis of sIg. These findings indicate that lectin binding generates signals via sIg but does not mediate endocytosis, potentially maintaining a supportive antigen-independent signal in vivo. Location of DC-SIGN in FL tissue revealed high levels in sinusoidlike structures and in some colocalized mononuclear cells, suggesting a role for lectin-expressing cells at this site. PMID:26194765

  18. High pressure liquid chormatography determination of the concentration and integrity of L-thyroxine in free T4 stock solution.

    PubMed

    Puig-Hernández, Jaime F; Jiménez-Velez, Braulio D

    2005-06-01

    Characterization studies were designed to evaluate the concentration and integrity of the L-thyroxine (T4) molecule (3,5,3',5'-tetraiodothyronine) in the free T4 stock solution (FT4SS) (code 99544). The determination of the concentration of T4 in FT4SS is critical to ensure that the free T4 calibrators and controls are manufactured with the least number of adjustments possible. The most significant conclusions drawn from these characterization studies are the following: (1) An accurate and sensitive HPLC method has been developed to measure the T4 concentration in FT4SS. The root cause of the failure of FT4SS to pass retest/ review is the presence of an unknown T4 degradation product with significantly higher molar extinction coefficient at 230 nm than T4 itself. The L-thyroxine concentration reference comparison spectrophotometric test with the current 43 to 58 ug/ml specification range (as per scp.99544, ed. 13A) is adequate to monitor the generation of the unknown T4 degradation product. The characterized T4 degradation product is not 3,5,3'-triiodo-thyronine (T3) and it is suspected that the identity of the degradation product is reverse T3 (3,3',5'-triiodothyronine). The use of sodium l-thyroxine pentahydrate (Na- T4-5H2O) as the equivalent of T4 (free base) is adequate provided that an excess of 15% over the desired amount of T4 is weighed. PMID:16116934

  19. Core-to-valence spectroscopic detection of the CH{sub 2}Br radical and element-specific femtosecond photodissociation dynamics of CH{sub 2}IBr

    SciTech Connect

    Attar, Andrew R.; Piticco, Lorena; Leone, Stephen R.

    2014-10-28

    Element-specific single photon photodissociation dynamics of CH{sub 2}IBr and core-to-valence absorption spectroscopy of CH{sub 2}Br radicals are investigated using femtosecond high-harmonic extreme ultraviolet (XUV) transient absorption spectroscopy. Photodissociation of CH{sub 2}IBr along both the C–I or C–Br reaction coordinates is observed in real-time following excitation at 266 nm. At this wavelength, C–I dissociation is the dominant reaction channel and C–Br dissociation is observed as a minor pathway. Both photodissociation pathways are probed simultaneously through individual 4d(I) N{sub 4/5} and 3d(Br) M{sub 4/5} core-to-valence transitions. The 3d(Br) M{sub 4/5} pre-edge absorption spectrum of the CH{sub 2}Br radical photoproduct corresponding to the C–I dissociation channel is characterized for the first time. Although the radical's singly occupied molecular orbital (SOMO) is mostly localized on the central carbon atom, the 3d(Br) → π{sup *}(SOMO) resonances at 68.5 eV and 69.5 eV are detected 2 eV below the parent molecule 3d(Br) → σ{sup *}(LUMO) transitions. Core-to-valence XUV absorption spectroscopy provides a unique probe of the local electronic structure of the radical species in reference to the Br reporter atom. The measured times for C–I dissociation leading to I and I{sup *} atomic products are 48 ± 12 fs and 44 ± 4 fs, respectively, while the measured C–Br dissociation time leading to atomic Br is 114 ± 17 fs. The investigation performed here demonstrates the capability of femtosecond time-resolved core-level spectroscopy utilizing multiple reporter atoms simultaneously.

  20. DC-SIGN expression on podocytes and its role in inflammatory immune response of lupus nephritis.

    PubMed

    Cai, Minchao; Zhou, Tong; Wang, Xuan; Shang, Minghua; Zhang, Yueyue; Luo, Maocai; Xu, Chundi; Yuan, Weijie

    2016-03-01

    Podocytes, the main target of immune complex, participate actively in the development of glomerular injury as immune cells. Dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) is an innate immune molecular that has an immune recognition function, and is involved in mediation of cell adhesion and immunoregulation. Here we explored the expression of DC-SIGN on podocytes and its role in immune and inflammatory responses in lupus nephritis (LN). Expression of DC-SIGN and immunoglobulin (Ig)G1 was observed in glomeruli of LN patients. DC-SIGN was co-expressed with nephrin on podocytes. Accompanied by increased proteinuria of LN mice, DC-SIGN and IgG1 expressions were observed in the glomeruli from 20 weeks, and the renal function deteriorated up to 24 weeks. Mice with anti-DC-SIGN antibody showed reduced proteinuria and remission of renal function. After the podocytes were stimulated by serum of LN mice in vitro, the expression of DC-SIGN, major histocompatibility complex (MHC) class II and CD80 was up-regulated, stimulation of T cell proliferation was enhanced and the interferon (IFN)-γ/interleukin (IL)-4 ratio increased. However, anti-DC-SIGN antibody treatment reversed these events. These results suggested that podocytes in LN can exert DC-like function through their expression of DC-SIGN, which may be involved in immune and inflammatory responses of renal tissues. However, blockage of DC-SIGN can inhibit immune functions of podocytes, which may have preventive and therapeutic effects. PMID:26440060

  1. Time-dependent chemical compositions of 13N and 15O induced in air by the operation of a high energy electron accelerator.

    PubMed

    Endo, A; Henshaw, J; Mignanelli, M A

    1998-04-01

    Time-dependent chemical compositions for 13N and 15O induced in the air atmosphere of a high energy electron accelerator room have been studied using a computer simulation method. A radiation chemistry model was developed to describe the chemical reactions of 13N and 15O species with the air molecules and their radiolytic products. By assuming several chemical forms of 13N and 15O generated by the (gamma, n) reaction, the variations of the concentrations of 13N and 15O species were simulated under a radiation field. From the comparison between the simulations and experiment in a 100 MeV electron linear accelerator (linac) facility, the following conclusions were obtained: (1) Just after the (gamma, n) reaction, 25-50% of 13N and 15O are present as atoms (13N, 15O) and/or their ions (13N+, 15O+) and the remainder as nitrogen and oxygen molecules (13NN, 15OO) and/or their ions (13NN+, 15OO+); (2) Neutralization of 13N+ and 15O+ ions into 13N and 15O atoms occurs instantaneously and the same is the case with the neutralization of 13NN+ and 15OO+ ions to 13NN and 15OO molecules; (3) The neutralized 13N and 15O atoms react with the air molecules and the radiolytic products to form nitrogen oxide compounds and ozone, while 13NN and 15OO remain as these molecules. Factors that control the chemical reactions of 13N and 15O are discussed. PMID:9525420

  2. Role of Dendritic Cells in Antibody-Dependent Enhancement of Dengue Virus Infection▿

    PubMed Central

    Boonnak, Kobporn; Slike, Bonnie M.; Burgess, Timothy H.; Mason, Randall M.; Wu, Shuenn-Jue; Sun, Peifang; Porter, Kevin; Rudiman, Irani Fianza; Yuwono, Djoko; Puthavathana, Pilaipan; Marovich, Mary A.

    2008-01-01

    Dengue viruses (DV), composed of four distinct serotypes (DV1 to DV4), cause 50 to 100 million infections annually. Durable homotypic immunity follows infection but may predispose to severe subsequent heterotypic infections, a risk conferred in part by the immune response itself. Antibody-dependent enhancement (ADE), a process best described in vitro, is epidemiologically linked to complicated DV infections, especially in Southeast Asia. Here we report for the first time the ADE phenomenon in primary human dendritic cells (DC), early targets of DV infection, and human cell lines bearing Fc receptors. We show that ADE is inversely correlated with surface expression of DC-SIGN (DC-specific intercellular adhesion molecule-3-grabbing nonintegrin) and requires Fc gamma receptor IIa (FcγRIIa). Mature DC exhibited ADE, whereas immature DC, expressing higher levels of DC-SIGN and similar FcγRIIa levels, did not undergo ADE. ADE results in increased intracellular de novo DV protein synthesis, increased viral RNA production and release, and increased infectivity of the supernatants in mature DC. Interestingly, tumor necrosis factor alpha and interleukin-6 (IL-6), but not IL-10 and gamma interferon, were released in the presence of dengue patient sera but generally only at enhancement titers, suggesting a signaling component of ADE. FcγRIIa inhibition with monoclonal antibodies abrogated ADE and associated downstream consequences. DV versatility in entry routes (FcγRIIa or DC-SIGN) in mature DC broadens target options and suggests additional ways for DC to contribute to the pathogenesis of severe DV infection. Studying the cellular targets of DV infection and their susceptibility to ADE will aid our understanding of complex disease and contribute to the field of vaccine development. PMID:18272578

  3. Role of dendritic cells in antibody-dependent enhancement of dengue virus infection.

    PubMed

    Boonnak, Kobporn; Slike, Bonnie M; Burgess, Timothy H; Mason, Randall M; Wu, Shuenn-Jue; Sun, Peifang; Porter, Kevin; Rudiman, Irani Fianza; Yuwono, Djoko; Puthavathana, Pilaipan; Marovich, Mary A

    2008-04-01

    Dengue viruses (DV), composed of four distinct serotypes (DV1 to DV4), cause 50 to 100 million infections annually. Durable homotypic immunity follows infection but may predispose to severe subsequent heterotypic infections, a risk conferred in part by the immune response itself. Antibody-dependent enhancement (ADE), a process best described in vitro, is epidemiologically linked to complicated DV infections, especially in Southeast Asia. Here we report for the first time the ADE phenomenon in primary human dendritic cells (DC), early targets of DV infection, and human cell lines bearing Fc receptors. We show that ADE is inversely correlated with surface expression of DC-SIGN (DC-specific intercellular adhesion molecule-3-grabbing nonintegrin) and requires Fc gamma receptor IIa (FcgammaRIIa). Mature DC exhibited ADE, whereas immature DC, expressing higher levels of DC-SIGN and similar FcgammaRIIa levels, did not undergo ADE. ADE results in increased intracellular de novo DV protein synthesis, increased viral RNA production and release, and increased infectivity of the supernatants in mature DC. Interestingly, tumor necrosis factor alpha and interleukin-6 (IL-6), but not IL-10 and gamma interferon, were released in the presence of dengue patient sera but generally only at enhancement titers, suggesting a signaling component of ADE. FcgammaRIIa inhibition with monoclonal antibodies abrogated ADE and associated downstream consequences. DV versatility in entry routes (FcgammaRIIa or DC-SIGN) in mature DC broadens target options and suggests additional ways for DC to contribute to the pathogenesis of severe DV infection. Studying the cellular targets of DV infection and their susceptibility to ADE will aid our understanding of complex disease and contribute to the field of vaccine development. PMID:18272578

  4. Mitochondria in relation to cancer metastasis: introduction to a mini-review series.

    PubMed

    Pedersen, Peter L

    2012-12-01

    This introductory article and those that follow focus on the roles that mitochondria may have in cancer metastasis (spreading) that all too frequently leads to death of cancer patients. The history of cancer dates back in time to several thousand years BC and continues to this day. Although billions of dollars have been invested, numerous cancer researchers/scientists and oncologist located at universities, hospitals, cancer centers, commercial entities (companies), and government agencies have been unable to discover "magic bullets" to quickly silence most cancers. That is, agents that are effective not only in eradicating the primary tumor at its site of origin, but eradicating also distant tumors that have arisen therefrom via metastatic cells. Fortunately, in recent years some researchers have obtained evidence that the mitochondria of cancer cells are involved not only in providing in part the necessary energy (ATP) to fuel their growth, but hold the secrets to their immortality, and propensity to metastasize (spread) from their original site of origin to other body locations. This introductory article, as well as those that follow, focus on the possible roles of mitochondria in cancer metastasis as well as strategies to arrest cancer metastasis based on this knowledge. Ideally, for a patient to become "cancer free" the anticancer agent/agents used must 1) eradicate the primary tumor at its site of origin, 2) eradicate any tumors at other body locations that have arisen via metastasis, and 3) eradicate any tumor cells that remain in the blood, i.e., circulating tumor cells. One such agent that holds promise for doing all three is the small molecule 3-bromopyruvate (3BP) discovered in the author's laboratory by Dr. Young H. Ko near the turn of the century to be a potent anti-cancer agent [Ko et al.(2001) Can Lett 173:83-91]. PMID:22926290

  5. Human Milk Blocks DC-SIGN–Pathogen Interaction via MUC1

    PubMed Central

    Koning, Nathalie; Kessen, Sabine F. M.; Van Der Voorn, J. Patrick; Appelmelk, Ben J.; Jeurink, Prescilla V.; Knippels, Leon M. J.; Garssen, Johan; Van Kooyk, Yvette

    2015-01-01

    Beneficial effects of breastfeeding are well-recognized and include both immediate neonatal protection against pathogens and long-term protection against allergies and autoimmune diseases. Although several proteins have been identified to have anti-viral or anti-bacterial effects like secretory IgA or lactoferrin, the mechanisms of immune modulation are not fully understood. Recent studies identified important beneficial effects of glycans in human milk, such as those expressed in oligosaccharides or on glycoproteins. Glycans are recognized by the carbohydrate receptors C-type lectins on dendritic cell (DC) and specific tissue macrophages, which exert important functions in immune modulation and immune homeostasis. A well-characterized C-type lectin is dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN), which binds terminal fucose. The present study shows that in human milk, MUC1 is the major milk glycoprotein that binds to the lectin domain of DC-SIGN and prevents pathogen interaction through the presence of Lewis x-type oligosaccharides. Surprisingly, this was specific for human milk, as formula, bovine or camel milk did not show any presence of proteins that interacted with DC-SIGN. The expression of DC-SIGN is found in young infants along the entire gastrointestinal tract. Our data thus suggest the importance of human milk glycoproteins for blocking pathogen interaction to DC in young children. Moreover, a potential benefit of human milk later in life in shaping the infants immune system through DC-SIGN cannot be ruled out. PMID:25821450

  6. The relationship of interacting immunological components in dengue pathogenesis

    PubMed Central

    2009-01-01

    The World Health Organization (WHO) estimates that there are over 50 million cases of dengue fever reported annually and approximately 2.5 billion people are at risk. Mild dengue fever presents with headache, fever, rash, myalgia, osteogenic pain, and lethargy. Severe disease can manifest as dengue shock syndrome (DSS) or dengue hemorrhagic fever (DHF). Symptoms of DSS/DHF are leukopenia, low blood volume and pressure encephalitis, cold and sweaty skin, gastrointestinal bleeding, and spontaneous bleeding from gums and nose. Currently, there are no therapeutics available beyond supportive care and untreated complicated dengue fever can have a 50% mortality rate. According to WHO DSS/DHF is the leading cause of childhood mortality in some Asian countries. Dendritic cells are professional antigen presenting cells that are primary targets in a dengue infection. Dengue binds to Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin (DC-SIGN). DC-SIGN has a high affinity for ICAM3 which is expressed in activating T-cells. Previous studies have demonstrated an altered T-cell phenotype expressed in dengue infected patients that could be potentially mediated by dengue-infected DCs. Dengue is enhanced by three interacting components of the immune system. Dengue begins by infecting dendritic cells which in immature dendritic cells is mediated by DC-SIGN. In mature dendritic cells, antibodies can enhance dengue infection via Fc receptors. Downstream of dendritic cells T-cells become activated and generate the very cytokines implicated in vascular leak and shock in addition to activating effector cells. Both the virus and the antibodies are involved in release of complement and anaphylatoxins which can cause or exacerbate DHF/DSS. These systems are inextricable and strongly associated with dengue pathogenesis. PMID:19941667

  7. Analyses at High Spatial Resolution of Organic Molecules in Extraterrestrial Samples: Two-Step Laser Mass Spectrometry: Search for Polycyclic Aromatic Hydrocarbons in Antarctic Meteorite and Micrometeorite Samples

    NASA Technical Reports Server (NTRS)

    Zare, Richard N.

    1998-01-01

    Perhaps the best way to summarize the past three-year grant period is to cite the publications and present a brief synopsis of each: 1. "Indigenous Polycyclic Aromatic Hydrocarbon Molecules in Circumstellar Graphite Grains." Bulk C-12/C-13 isotope ratios observed in some graphite grains extracted from primitive meteorites point strongly to a circumstellar origin. By applying our technique of microprobe two-step laser desorption laser ionization mass spectrometry ((mu)L(sup 2)MS) to individual circumstellar graphite grains we have measured the C-12/C-13 isotope ratio of various polycyclic aromatic hydrocarbons (PAHS) found in these grains. 2. "Deuterium Enrichments in Cluster IDPS," Large enrichments in the D/H isotope ratios in IDPs likely arise from the preservation of presolar molecules. 3. "Evidence for thermalization of surface-disorder molecules at heating rates of 10(exp 8) K/s". A careful study of the ((mu)L(sup 2)MS) of aniline-d(sub 7) from a single-crystal surface (0001) of sapphire (al2O3) shows that all measured properties are consistent with a thermal mechanism for desorption. 4. "Search for past life on Mars; possible relic biogenic activity in Martian meteorite ALH 84001. The authors examined the Martian meteorite ALH 84001 and found several lines of evidence compatible with existence of past primitive (single-cell) life on early Mars. 5. "Microprobe two-step laser mass spectrometry as an analytical tool for meteorite samples". THis paper presents a comprehensive review of (mu)L(sup 2)MS and how this technique can be applied to meteoritic samples. 6. "Indigenous polycyclic aromatic hydrocarbons in circumstellar graphite grains from primitive meteorites". The C-12/C-13 isotope ratios were measured for PAHs in a total of 89 spherical graphite grains. 7. "Observation of indigenous polycyclic aromatic hydrocarbons in "Giant" carbonaceous antarctic micrometeorites." The (mu)L(sup 2)MS method was used to establish the nature and distribution of PAHs in

  8. Microglia Transcriptome Changes in a Model of Depressive Behavior after Immune Challenge

    PubMed Central

    Gonzalez-Pena, Dianelys; Nixon, Scott E.; O’Connor, Jason C.; Southey, Bruce R.; Lawson, Marcus A.; McCusker, Robert H.; Borras, Tania; Machuca, Debbie; Hernandez, Alvaro G.; Dantzer, Robert; Kelley, Keith W.; Rodriguez-Zas, Sandra L.

    2016-01-01

    Depression symptoms following immune response to a challenge have been reported after the recovery from sickness. A RNA-Seq study of the dysregulation of the microglia transcriptome in a model of inflammation-associated depressive behavior was undertaken. The transcriptome of microglia from mice at day 7 after Bacille Calmette Guérin (BCG) challenge was compared to that from unchallenged Control mice and to the transcriptome from peripheral macrophages from the same mice. Among the 562 and 3,851 genes differentially expressed between BCG-challenged and Control mice in microglia and macrophages respectively, 353 genes overlapped between these cells types. Among the most differentially expressed genes in the microglia, serum amyloid A3 (Saa3) and cell adhesion molecule 3 (Cadm3) were over-expressed and coiled-coil domain containing 162 (Ccdc162) and titin-cap (Tcap) were under-expressed in BCG-challenged relative to Control. Many of the differentially expressed genes between BCG-challenged and Control mice were associated with neurological disorders encompassing depression symptoms. Across cell types, S100 calcium binding protein A9 (S100A9), interleukin 1 beta (Il1b) and kynurenine 3-monooxygenase (Kmo) were differentially expressed between challenged and control mice. Immune response, chemotaxis, and chemokine activity were among the functional categories enriched by the differentially expressed genes. Functional categories enriched among the 9,117 genes differentially expressed between cell types included leukocyte regulation and activation, chemokine and cytokine activities, MAP kinase activity, and apoptosis. More than 200 genes exhibited alternative splicing events between cell types including WNK lysine deficient protein kinase 1 (Wnk1) and microtubule-actin crosslinking factor 1(Macf1). Network visualization revealed the capability of microglia to exhibit transcriptome dysregulation in response to immune challenge still after resolution of sickness symptoms

  9. Effect of Culture Supernatant Derived from Trichophyton Rubrum Grown in the Nail Medium on the Innate Immunity-related Molecules of HaCaT

    PubMed Central

    Huang, Xin-Zhu; Liang, Pan-Pan; Ma, Han; Yi, Jin-Ling; Yin, Song-Chao; Chen, Zhi-Rui; Li, Mei-Rong; Lai, Wei; Chen, Jian

    2015-01-01

    Background: Trichophyton rubrum is superficial fungi characteristically confined to dead keratinized tissues. These observations suggest that the soluble components released by the fungus could influence the host immune response in a cell in contact-free manner. Therefore, this research aimed to analyze whether the culture supernatant derived from T. rubrum grown in the nail medium could elicit the immune response of keratinocyte effectively. Methods: The culture supernatants of two strains (T1a, TXHB) were compared for the β-glucan concentrations and their capacity to impact the innate immunity of keratinocytes. The β-glucan concentrations in the supernatants were determined with the fungal G-test kit and protein concentrations with bicinchoninic acid protein quantitative method, then HaCaT was stimulated with different concentrations of culture supernatants by adopting morphological method to select a suitable dosage. Expressions of host defense genes were assessed by quantitative polymerase chain reaction after the HaCaT was stimulated with the culture supernatants. Data were analyzed with one-way analysis of variance, followed by the least significant difference test. Results: The T. rubrum strains (T1a and TXHB) released β-glucan of 87.530 ± 37.581 pg/ml and 15.747 ± 6.453 pg/ml, respectively into the media. The messenger RNA (mRNA) expressions of toll-like receptor-2 (TLR2), TLR4, and CARD9 were moderately up-regulated in HaCaT within 6-h applications of both supernatants. HaCaT cells were more responsive to T1a than TXHB. The slight increase of dendritic cells-specific intercellular adhesion molecule 3-grabbing nonintegrin expression was faster and stronger, induced by T1a supernatant than TXHB. The moderate decreases of RNase 7, the slight up-regulations of Dectin-1 and interleukin-8 at the mRNA level were detected only in response to T1a rather than TXHB. After a long-time contact, all the elevated defense genes decreased after 24 h. Conclusion: The

  10. Inhibition of Predator Attraction to Kairomones by Non-Host Plant Volatiles for Herbivores: A Bypass-Trophic Signal

    PubMed Central

    Zhang, Qing-He; Schlyter, Fredrik

    2010-01-01

    Background Insect predators and parasitoids exploit attractive chemical signals from lower trophic levels as kairomones to locate their herbivore prey and hosts. We hypothesized that specific chemical cues from prey non-hosts and non-habitats, which are not part of the trophic chain, are also recognized by predators and would inhibit attraction to the host/prey kairomone signals. To test our hypothesis, we studied the olfactory physiology and behavior of a predaceous beetle, Thanasimus formicarius (L.) (Coleoptera: Cleridae), in relation to specific angiosperm plant volatiles, which are non-host volatiles (NHV) for its conifer-feeding bark beetle prey. Methodology/Principal Findings Olfactory detection in the clerid was confirmed by gas chromatography coupled to electroantennographic detection (GC-EAD) for a subset of NHV components. Among NHV, we identified two strongly antennally active molecules, 3-octanol and 1-octen-3-ol. We tested the potential inhibition of the combination of these two NHV on the walking and flight responses of the clerid to known kairomonal attractants such as synthetic mixtures of bark beetle (Ips spp.) aggregation pheromone components (cis-verbenol, ipsdienol, and E-myrcenol) combined with conifer (Picea and Pinus spp.) monoterpenes (α-pinene, terpinolene, and Δ3-carene). There was a strong inhibitory effect, both in the laboratory (effect size d = −3.2, walking bioassay) and in the field (d = −1.0, flight trapping). This is the first report of combining antennal detection (GC-EAD) and behavioral responses to identify semiochemical molecules that bypass the trophic system, signaling habitat information rather than food related information. Conclusions/Significance Our results, along with recent reports on hymenopteran parasitoids and coleopteran predators, suggest that some NHV chemicals for herbivores are part of specific behavioral signals for the higher trophic level and not part of a background noise. Such bypass

  11. Microglia Transcriptome Changes in a Model of Depressive Behavior after Immune Challenge.

    PubMed

    Gonzalez-Pena, Dianelys; Nixon, Scott E; O'Connor, Jason C; Southey, Bruce R; Lawson, Marcus A; McCusker, Robert H; Borras, Tania; Machuca, Debbie; Hernandez, Alvaro G; Dantzer, Robert; Kelley, Keith W; Rodriguez-Zas, Sandra L

    2016-01-01

    Depression symptoms following immune response to a challenge have been reported after the recovery from sickness. A RNA-Seq study of the dysregulation of the microglia transcriptome in a model of inflammation-associated depressive behavior was undertaken. The transcriptome of microglia from mice at day 7 after Bacille Calmette Guérin (BCG) challenge was compared to that from unchallenged Control mice and to the transcriptome from peripheral macrophages from the same mice. Among the 562 and 3,851 genes differentially expressed between BCG-challenged and Control mice in microglia and macrophages respectively, 353 genes overlapped between these cells types. Among the most differentially expressed genes in the microglia, serum amyloid A3 (Saa3) and cell adhesion molecule 3 (Cadm3) were over-expressed and coiled-coil domain containing 162 (Ccdc162) and titin-cap (Tcap) were under-expressed in BCG-challenged relative to Control. Many of the differentially expressed genes between BCG-challenged and Control mice were associated with neurological disorders encompassing depression symptoms. Across cell types, S100 calcium binding protein A9 (S100A9), interleukin 1 beta (Il1b) and kynurenine 3-monooxygenase (Kmo) were differentially expressed between challenged and control mice. Immune response, chemotaxis, and chemokine activity were among the functional categories enriched by the differentially expressed genes. Functional categories enriched among the 9,117 genes differentially expressed between cell types included leukocyte regulation and activation, chemokine and cytokine activities, MAP kinase activity, and apoptosis. More than 200 genes exhibited alternative splicing events between cell types including WNK lysine deficient protein kinase 1 (Wnk1) and microtubule-actin crosslinking factor 1(Macf1). Network visualization revealed the capability of microglia to exhibit transcriptome dysregulation in response to immune challenge still after resolution of sickness symptoms

  12. Mannosylated Mucin-Type Immunoglobulin Fusion Proteins Enhance Antigen-Specific Antibody and T Lymphocyte Responses

    PubMed Central

    Johansson, Tomas; Nilsson, Anki; Chatzissavidou, Nathalie; Sjöblom, Magnus; Rova, Ulrika; Holgersson, Jan

    2012-01-01

    Targeting antigens to antigen-presenting cells (APC) improve their immunogenicity and capacity to induce Th1 responses and cytotoxic T lymphocytes (CTL). We have generated a mucin-type immunoglobulin fusion protein (PSGL-1/mIgG2b), which upon expression in the yeast Pichia pastoris became multivalently substituted with O-linked oligomannose structures and bound the macrophage mannose receptor (MMR) and dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN) with high affinity in vitro. Here, its effects on the humoral and cellular anti-ovalbumin (OVA) responses in C57BL/6 mice are presented. OVA antibody class and subclass responses were determined by ELISA, the generation of anti-OVA CTLs was assessed in 51Cr release assays using in vitro-stimulated immune spleen cells from the different groups of mice as effector cells and OVA peptide-fed RMA-S cells as targets, and evaluation of the type of Th cell response was done by IFN-γ, IL-2, IL-4 and IL-5 ELISpot assays. Immunizations with the OVA − mannosylated PSGL-1/mIgG2b conjugate, especially when combined with the AbISCO®-100 adjuvant, lead to faster, stronger and broader (with regard to IgG subclass) OVA IgG responses, a stronger OVA-specific CTL response and stronger Th1 and Th2 responses than if OVA was used alone or together with AbISCO®-100. Also non-covalent mixing of mannosylated PSGL-1/mIgG2b, OVA and AbISCO®-100 lead to relatively stronger humoral and cellular responses. The O-glycan oligomannoses were necessary because PSGL-1/mIgG2b with mono- and disialyl core 1 structures did not have this effect. Mannosylated mucin-type fusion proteins can be used as versatile APC-targeting molecules for vaccines and as such enhance both humoral and cellular immune responses. PMID:23071675

  13. A Systematic Approach for Computing Zero-Point Energy, Quantum Partition Function, and Tunneling Effect Based on Kleinert’s Variational Perturbation Theory

    PubMed Central

    Wong, Kin-Yiu; Gao, Jiali

    2009-01-01

    In this paper, we describe an automated integration-free path-integral (AIF-PI) method, based on Kleinert’s variational perturbation (KP) theory, to treat internuclear quantum-statistical effects in molecular systems. We have developed an analytical method to obtain the centroid potential as a function of the variational parameter in the KP theory, which avoids numerical difficulties in path-integral Monte Carlo or molecular dynamics simulations, especially at the limit of zero-temperature. Consequently, the variational calculations using the KP theory can be efficiently carried out beyond the first order, i.e., the Giachetti-Tognetti-Feynman-Kleinert variational approach, for realistic chemical applications. By making use of the approximation of independent instantaneous normal modes (INM), the AIF-PI method can readily be applied to many-body systems. Previously, we have shown that in the INM approximation, the AIF-PI method is accurate for computing the quantum partition function of a water molecule (3 degrees of freedom) and the quantum correction factor for the collinear H3 reaction rate (2 degrees of freedom). In this work, the accuracy and properties of the KP theory are further investigated by using the first three order perturbations on an asymmetric double-well potential, the bond vibrations of H2, HF, and HCl represented by the Morse potential, and a proton-transfer barrier modeled by the Eckart potential. The zero-point energy, quantum partition function, and tunneling factor for these systems have been determined and are found to be in excellent agreement with the exact quantum results. Using our new analytical results at the zero-temperature limit, we show that the minimum value of the computed centroid potential in the KP theory is in excellent agreement with the ground state energy (zero-point energy) and the position of the centroid potential minimum is the expectation value of particle position in wave mechanics. The fast convergent property of

  14. Inhibition of HIV-1 transmission in trans from dendritic cells to CD4+ T lymphocytes by natural antibodies to the CRD domain of DC-SIGN purified from breast milk and intravenous immunoglobulins

    PubMed Central

    Requena, Mary; Bouhlal, Hicham; Nasreddine, Nadine; Saidi, Hela; Gody, Jean-Chrysostome; Aubry, Sylvie; Grésenguet, Gérard; Kazatchkine, Michel D; Sekaly, Rafick-Pierre; Bélec, Laurent; Hocini, Hakim

    2008-01-01

    The present study demonstrates that human breast milk and normal human polyclonal immunoglobulins purified from plasma [intravenous immunoglobulins (IVIg)] contain functional natural immunoglobulin A (IgA) and IgG antibodies directed against the carbohydrate recognition domain (CRD) domain of the dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) molecule, which is involved in the binding of human immunodeficiency virus (HIV)-1 to dendritic cells (DCs). Antibodies to DC-SIGN CRD were affinity-purified on a matrix to which a synthetic peptide corresponding to the N-terminal CRD domain (amino-acid 342–amino-acid 371) had been coupled. The affinity-purified antibodies bound to the DC-SIGN peptide and to the native DC-SIGN molecule expressed by HeLa DC-SIGN+ cells and immature monocyte-derived dendritic cells (iMDDCs), in a specific and dose-dependent manner. At an optimal dose of 200 µg/ml, natural antibodies to DC-SIGN CRD peptide purified from breast milk and IVIg stained 25 and 20% of HeLa DC-SIGN+ cells and 32 and 12% of iMDDCs, respectively. Anti-DC-SIGN CRD peptide antibodies inhibited the attachment of virus to HeLa DC-SIGN by up to 78% and the attachment to iMDDCs by only 20%. Both breast milk- and IVIg-derived natural antibodies to the CRD peptide inhibited 60% of the transmission in trans of HIV-1JRCSF, an R5-tropic strain, from iMDDCs to CD4+ T lymphocytes. Taken together, these observations suggest that the attachment of HIV to DCs and transmission in trans to autologous CD4+ T lymphocytes occur through two independent mechanisms. Our data support a role of natural antibodies to DC-SIGN in the modulation of postnatal HIV transmission through breast-feeding and in the natural host defence against HIV-1 in infected individuals. PMID:17999675

  15. Brugia malayi Antigen (BmA) Inhibits HIV-1 Trans-Infection but Neither BmA nor ES-62 Alter HIV-1 Infectivity of DC Induced CD4+ Th-Cells

    PubMed Central

    Mouser, Emily E. I. M.; Pollakis, Georgios; Yazdanbakhsh, Maria; Harnett, William

    2016-01-01

    One of the hallmarks of HIV-1 disease is the association of heightened CD4+ T-cell activation with HIV-1 replication. Parasitic helminths including filarial nematodes have evolved numerous and complex mechanisms to skew, dampen and evade human immune responses suggesting that HIV-1 infection may be modulated in co-infected individuals. Here we studied the effects of two filarial nematode products, adult worm antigen from Brugia malayi (BmA) and excretory-secretory product 62 (ES-62) from Acanthocheilonema viteae on HIV-1 infection in vitro. Neither BmA nor ES-62 influenced HIV-1 replication in CD4+ enriched T-cells, with either a CCR5- or CXCR4-using virus. BmA, but not ES-62, had the capacity to bind the C-type lectin dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) thereby inhibiting HIV-1 trans-infection of CD4+ enriched T-cells. As for their effect on DCs, neither BmA nor ES-62 could enhance or inhibit DC maturation as determined by CD83, CD86 and HLA-DR expression, or the production of IL-6, IL-10, IL-12 and TNF-α. As expected, due to the unaltered DC phenotype, no differences were found in CD4+ T helper (Th) cell phenotypes induced by DCs treated with either BmA or ES-62. Moreover, the HIV-1 susceptibility of the Th-cell populations induced by BmA or ES-62 exposed DCs was unaffected for both CCR5- and CXCR4-using HIV-1 viruses. In conclusion, although BmA has the potential capacity to interfere with HIV-1 transmission or initial viral dissemination through preventing the virus from interacting with DCs, no differences in the Th-cell polarizing capacity of DCs exposed to BmA or ES-62 were observed. Neither antigenic source demonstrated beneficial or detrimental effects on the HIV-1 susceptibility of CD4+ Th-cells induced by exposed DCs. PMID:26808476

  16. Combined measurements of organic aerosol isotopic and chemical composition to investigate day-night differences in carbonaceous aerosol

    NASA Astrophysics Data System (ADS)

    Dusek, Ulrike; Holzinger, Rupert; Meijer, Harro A. J.; Röckmann, Thomas

    2014-05-01

    more strongly during night time than less volatile OC. (2) PTRMS measurements show that concentrations of small molecules with m/z <100 amu increase more strongly during night-time than concentrations of larger molecules. (3) d13C values of OC only show day-night differences for semi-volatile carbon desorbed at 150 °C. This indicates that isotopic properties of semi-volatile compounds are more indicative of regional sources and processes and of low volatility compounds by large-scale processes. The day-night differences of individual chemical compounds and compound classes will be further analyzed and discussed.

  17. FISH applications for genomics and plant breeding strategies in tomato and other solanaceous crops.

    PubMed

    Szinay, D; Bai, Y; Visser, R; de Jong, H

    2010-07-01

    This paper describes the use of advanced fluorescence in situ hybridization (FISH) technologies for genomics and breeding of tomato and related Solanum species. The first part deals with the major determinants of FISH technology: (1) spatial resolution, which depends on the diffraction limit of the microscope and the type of chromosome, chromatin or isolated DNA fibres as target for the hybridisation; (2) the detection sensitivity, which is limited by the sensitivity and dynamic range of the CCD camera and the quality of the microscope, and the amplification system of the weak signals from tiny probe molecules; (3) simultaneous detection of multiple probes labelled directly or indirectly with up to 5 different fluorophores, whether or not in different combinations and/or mixed at different ratios. The power and usability of such multicolour FISH is indispensable when large numbers of bacterial artificial chromosomes (BACs) or other vectors with genomic DNA are available. Mapping of multiple BACs on chromosomes are powerful instruments confirming their assumed genetic position, whereas pooled BACs for a given chromosome arm will reveal the gaps between the BACs or derived contigs of their physical maps. Tandem and dispersed repeats, which are abundant in the genomes of most species, can be analysed in repeat bar coding FISH, showing the major blocks of repeats in heterochromatin and euchromatin areas. Repeat-rich areas of the chromosomes can also be demonstrated by hybridisation of probed Cot fractions of sheared genomic DNA; a powerful method to elucidate the heterochromatin domains for genomic studies. In addition, unlabelled Cot DNA, as blocking agent in BAC-FISH painting, suppresses repetitive sequences from the BACs to hybridise on the chromosomes. Cross-species BAC-FISH painting with labelled probes from tomato and potato BACs and hybridised on the chromosomes of related species, under appropriate conditions, is a powerful instrument to demonstrate chromosomal

  18. A Hybrid Chalcone Combining the Trimethoxyphenyl and Isatinyl Groups Targets Multiple Oncogenic Proteins and Pathways in Hepatocellular Carcinoma Cells

    PubMed Central

    Cao, Lili; Zhang, Lijun; Zhao, Xiang; Zhang, Ye

    2016-01-01

    Small molecule inhibitors that can simultaneously inhibit multiple oncogenic proteins in essential pathways are promising therapeutic chemicals for hepatocellular carcinoma (HCC). To combine the anticancer effects of combretastatins, chalcones and isatins, we synthesized a novel hybrid molecule 3’,4’,5’-trimethoxy-5-chloro-isatinylchalcone (3MCIC). 3MCIC inhibited proliferation of cultured HepG2 cells, causing rounding-up of the cells and massive vacuole accumulation in the cytoplasm. Paxillin and focal adhesion plaques were downregulated by 3MCIC. Surprisingly, unlike the microtubule (MT)-targeting agent CA-4 that inhibits tubulin polymerization, 3MCIC stabilized tubulin polymers both in living cells and in cell lysates. 3MCIC treatment reduced cyclin B1, CDK1, p-CDK1/2, and Rb, but increased p53 and p21. Moreover, 3MCIC caused GSK3β degradation by promoting GSK3β-Ser9 phosphorylation. Nevertheless, 3MCIC inhibited the Wnt/β-catenin pathway by downregulating β-catenin, c-Myc, cyclin D1 and E2F1. 3MCIC treatment not only activated the caspase-3-dependent apoptotic pathway, but also caused massive autophagy evidenced by rapid and drastic changes of LC3 and p62. 3MCIC also promoted cleavage and maturation of the lysosomal protease cathepsin D. Using ligand-affinity chromatography (LAC), target proteins captured onto the Sephacryl S1000-C12-3MCIC resins were isolated and analyzed by mass spectrometry (MS). Some of the LAC-MS identified targets, i.e., septin-2, vimentin, pan-cytokeratin, nucleolin, EF1α1/2, EBP1 (PA2G4), cyclin B1 and GSK3β, were further detected by Western blotting. Moreover, both septin-2 and HIF-1α decreased drastically in 3MCIC-treated HepG2 cells. Our data suggest that 3MCIC is a promising anticancer lead compound with novel targeting mechanisms, and also demonstrate the efficiency of LAC-MS based target identification in anticancer drug development. PMID:27525972

  19. Modeling Electrical Transport through Nucleic Acids

    NASA Astrophysics Data System (ADS)

    Qi, Jianqing

    Nucleic acids play a vital role in many biological systems and activities. In recent years, engineers and scientists have been interested in studying their electrical properties. The motivation for these studies stems from the following facts: (1) the bases, which form the building blocks of nucleic acids, have unique ionization potentials. Further, nucleic acids are one of the few nanomaterials that can be reproducibly manufactured with a high degree of accuracy (though admittedly their placement at desired locations remains a challenge). As a result, designed strands with specific sequences may offer unique device properties; (2) electrical methods offer potential for sequencing nucleic acids based on a single molecule; (3) electrical methods for disease detection based on the current flowing through nucleic acids are beginning to be demonstrated. While experiments in the above mentioned areas is promising, a deeper understanding of the electrical current flow through the nucleic acids needs to be developed. The modeling of current flowing in these molecules is complex because: (1) they are based on atomic scale contacts between nucleic acids and metal, which cannot be reproducibly built; (2) the conductivity of nucleic acids is easily influenced by the environment, which is constantly changing; and (3) the nucleic acids by themselves are floppy. This thesis focuses on the modeling of electrical transport through nucleic acids that are connected to two metal electrodes at nanoscale. We first develop a decoherent transport model for the double-stranded helix based on the Landauer-Buttiker framework. This model is rationalized by comparison with an experiment that measured the conductance of four different DNA strands. The developed model is then used to study the: (1) potential to make barriers and wells for quantum transport using specifically engineered sequences; (2) change in the electrical properties of a specific DNA strand with and without methylation; (3

  20. A Hybrid Chalcone Combining the Trimethoxyphenyl and Isatinyl Groups Targets Multiple Oncogenic Proteins and Pathways in Hepatocellular Carcinoma Cells.

    PubMed

    Cao, Lili; Zhang, Lijun; Zhao, Xiang; Zhang, Ye

    2016-01-01

    Small molecule inhibitors that can simultaneously inhibit multiple oncogenic proteins in essential pathways are promising therapeutic chemicals for hepatocellular carcinoma (HCC). To combine the anticancer effects of combretastatins, chalcones and isatins, we synthesized a novel hybrid molecule 3',4',5'-trimethoxy-5-chloro-isatinylchalcone (3MCIC). 3MCIC inhibited proliferation of cultured HepG2 cells, causing rounding-up of the cells and massive vacuole accumulation in the cytoplasm. Paxillin and focal adhesion plaques were downregulated by 3MCIC. Surprisingly, unlike the microtubule (MT)-targeting agent CA-4 that inhibits tubulin polymerization, 3MCIC stabilized tubulin polymers both in living cells and in cell lysates. 3MCIC treatment reduced cyclin B1, CDK1, p-CDK1/2, and Rb, but increased p53 and p21. Moreover, 3MCIC caused GSK3β degradation by promoting GSK3β-Ser9 phosphorylation. Nevertheless, 3MCIC inhibited the Wnt/β-catenin pathway by downregulating β-catenin, c-Myc, cyclin D1 and E2F1. 3MCIC treatment not only activated the caspase-3-dependent apoptotic pathway, but also caused massive autophagy evidenced by rapid and drastic changes of LC3 and p62. 3MCIC also promoted cleavage and maturation of the lysosomal protease cathepsin D. Using ligand-affinity chromatography (LAC), target proteins captured onto the Sephacryl S1000-C12-3MCIC resins were isolated and analyzed by mass spectrometry (MS). Some of the LAC-MS identified targets, i.e., septin-2, vimentin, pan-cytokeratin, nucleolin, EF1α1/2, EBP1 (PA2G4), cyclin B1 and GSK3β, were further detected by Western blotting. Moreover, both septin-2 and HIF-1α decreased drastically in 3MCIC-treated HepG2 cells. Our data suggest that 3MCIC is a promising anticancer lead compound with novel targeting mechanisms, and also demonstrate the efficiency of LAC-MS based target identification in anticancer drug development. PMID:27525972

  1. Processes Producing the Extremely Hot Ca and Mg Exospheres at Mercury

    NASA Astrophysics Data System (ADS)

    Killen, R. M.

    2015-12-01

    The Mercury Atmospheric and Surface Composition Spectrometer on the MESSENGER spacecraft observed calcium emisison in Mercury's exosphere on a near-daily basis for >16 Mercury years. The calcium was persistently concentrated in the dawn hemisphere and was of extreme temperature (>50,000K). Any mechanism producing the Mercurian Ca exosphere must explain the facts that the Ca is extremely hot, that it is seen almost exclusively on the dawnside of the planet, and that its content varies seasonally, not sporadically. In this paper we consider the energization processes. We start with the assumption that calcium is ejected into the exosphere by impact vaporization, initially in the form of simple molecules, and that they are subsequently dissociated by some process. We consider here simple diatomic molecules or their clusters, focusing on calcium oxides while acknowledging that Ca sulfides may also be the precursor molecules. The pathways we discuss are (1) impact vaporization producing Ca and Ca-oxide clusters, (2) electron-impact dissociation of CaO molecules, (3) spontaneous dissociation of Ca-bearing molecules following impact vaporization, and (4) photodissociation. The most likely origin of extremely hot Ca seen in Mercury's exosphere is photodissociation or dissociative photoionization of a precursor CaO molecule or clusters, or possibly some other diatomic molecule such as CaS, produced by impact vaporization. Photodissociation of the CaO molecule results in a hot Ca atom and an even hotter oxygen atom. This explains both the observation of hot refractories in Mercury's exosphere and the absence of observable oxygen (Vervack et al., 2015), which would rapidly escape from the exosphere. It has been shown previously that CaO clusters and even dimers are produced by evaporation of diopside, and that the dawnside origin of the Ca is the result of preferential impact vaporization in the ram direction as Mercury moves through the interplanetary medium. In addition to

  2. Association of Dectin-1 and DC-SIGN gene single nucleotide polymorphisms with fungal keratitis in the northern Han Chinese population

    PubMed Central

    Qu, Xiaoli; Che, Chengye; Gao, Ang; Lin, Jing; Wang, Nan; Du, Xing; Liu, Ying; Guo, Yanli; Chen, Wenjun

    2015-01-01

    Purpose Dendritic cell-associated C-type lectin-1 (Dectin-1) and dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) play a crucial role in the early procedure of fungal pathogen defenses. The present study evaluated the associations between Dectin-1 and DC-SIGN gene single nucleotide polymorphisms (SNPs) and susceptibility to fungal keratitis (FK) in the northern Han Chinese population. Methods The polymorphisms of Dectin-1 (rs17206002, rs3901533, rs11053613, and rs3901532) and DC-SIGN (rs4804803, rs2287886, rs735239, and rs735240) for 109 FK patients and 220 matched healthy controls were determined by PCR and DNA direct sequencing assay. Results Each SNP was consistent with Hardy–Weinberg equilibrium (p>0.05). The frequencies of genotypes and alleles for rs735239 and rs735240 (DC-SIGN) showed statistical differences between patients and control groups (p<0.05). The wild G allele of rs735239 and the wild A allele of rs735240 were significantly higher in patients (p = 0.003, OR = 1.766, 95% confidence interval [CI] 1.207–2.585; p = 0.014, OR = 1.609, 95% CI 1.100–2.355, respectively). No association with a risk of FK was found for the remaining SNPs (p>0.05) even after ruling out clinical characteristics, such as severity degree and case history. Carriers of the haplotype TC (rs4804803 and rs2287886) had a higher risk of developing fungal keratitis (p = 0.007, OR = 1.710, 95% CI 1.154–2.534). The distribution of haplotypes AG and GA (rs735239 and rs735240) between the two groups also showed significant differences (p = 0.014, p = 0.003, respectively). Conclusions Two SNPs of DC-SIGN (rs735239 and rs735240) are associated with susceptibility to FK in the northern Han Chinese population. The haplotypes of DC-SIGN may be susceptible to the risk of FK, whereas the analysis of Dectin-1 gene polymorphisms showed no significant association with FK risk. Further research with a larger sample is recommended. PMID:25883525

  3. Human Blood-Circulating Basophils Capture HIV-1 and Mediate Viral trans-Infection of CD4+ T Cells

    PubMed Central

    Jiang, Ai-Ping; Jiang, Jin-Feng; Guo, Ming-Gao; Jin, Yong-Mei; Li, Yu-Ye

    2015-01-01

    ABSTRACT Cell-associated HIV-1 infection has been proposed to play a pivotal role in the spread of HIV-1 infection. Granulocytes are a category of white blood cells, comprising mainly basophils, neutrophils, and eosinophils, and participate in various inflammatory reactions and defense against pathogens. Here, we investigated the role of human blood granulocytes in the dissemination of HIV-1. These cells were found to express a variety of HIV-1 attachment factors (HAFs). Basophils expressed HAFs dendritic cell (DC)-specific intercellular adhesion molecule 3 (ICAM3)-grabbing nonintegrin (DC-SIGN), DC immunoreceptor (DCIR), heparan sulfate proteoglycan (HSPG), and α4β7 integrin and mediated the most efficient capture of HIV-1 on the cell surface. Neutrophils were found to express DCIR and demonstrated limited efficiency of viral capture. Eosinophils expressed α4β7 integrin but exhibited little or no virus-binding capacity. Intriguingly, following direct contact with CD4+ T cells, viruses harbored on the surface of basophils were transferred to T cells. The contact between basophils and CD4+ T cells and formation of infectious synapses appeared necessary for efficient HIV-1 spread. In HIV-1-infected individuals, the frequency of basophils remained fairly stable over the course of disease, regardless of CD4+ T depletion or the emergence of AIDS-associated opportunistic infections. Collectively, our results provide novel insights into the roles of granulocytes, particularly basophils, in HIV-1 dissemination. Thus, strategies designed to prevent basophil-mediated viral capture and transfer may be developed into a new form of therapy. IMPORTANCE Cell-associated HIV-1 infection has been proposed to play a pivotal role in the spread of HIV-1 infection. Here, we demonstrated that human blood-circulating granulocytes, particularly basophils, can capture HIV-1 and mediate viral trans-infection of CD4+ T cells. The expression of a variety of HIV-1 attachment factors, such

  4. Resveratrol Induces Hepatic Mitochondrial Biogenesis Through the Sequential Activation of Nitric Oxide and Carbon Monoxide Production

    PubMed Central

    Kim, Seul-Ki; Joe, Yeonsoo; Zheng, Min; Kim, Hyo Jeong; Yu, Jae-Kyoung; Cho, Gyeong Jae; Chang, Ki Churl; Kim, Hyoung Kyu; Han, Jin; Ryter, Stefan W.

    2014-01-01

    Abstract Aims: Nitric oxide (NO) can induce mitochondrial biogenesis in cultured cells, through increased guanosine 3′,5′-monophosphate (cGMP), and activation of peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α). We sought to determine the role of NO, heme oxygenase-1 (HO-1), and its reaction product (carbon monoxide [CO]) in the induction of mitochondrial biogenesis by the natural antioxidant resveratrol. Results: S-nitroso-N-acetylpenicillamine (SNAP), an NO donor, induced mitochondrial biogenesis in HepG2 hepatoma cells, and in vivo, through stimulation of PGC-1α. NO-induced mitochondrial biogenesis required cGMP, and was mimicked by the cGMP analogue (8-bromoguanosine 3′,5′-cyclic monophosphate [8-Br-cGMP]). Activation of mitochondrial biogenesis by SNAP required HO-1, as it could be reversed by genetic interference of HO-1; and by treatment with the HO inhibitor tin-protoporphyrin-IX (SnPP) in vitro and in vivo. Cobalt protoporphyrin (CoPP)-IX, an HO-1 inducing agent, stimulated mitochondrial biogenesis in HepG2 cells, which could be reversed by the CO scavenger hemoglobin. Application of CO, using the CO-releasing molecule-3 (CORM-3), stimulated mitochondrial biogenesis in HepG2 cells, in a cGMP-dependent manner. Both CoPP and CORM-3-induced mitochondrial biogenesis required NF-E2-related factor-2 (Nrf2) activation and phosphorylation of Akt. The natural antioxidant resveratrol induced mitochondrial biogenesis in HepG2 cells, in a manner dependent on NO biosynthesis, cGMP synthesis, Nrf2-dependent HO-1 activation, and endogenous CO production. Furthermore, resveratrol preserved mitochondrial biogenesis during lipopolysaccharides-induced hepatic inflammation in vivo. Innovation and Conclusions: The complex interplay between endogenous NO and CO production may underlie the mechanism by which natural antioxidants induce mitochondrial biogenesis. Strategies aimed at improving mitochondrial biogenesis may be used as therapeutics

  5. The molecular mechanism of fullerene-inhibited aggregation of Alzheimer's β-amyloid peptide fragment

    NASA Astrophysics Data System (ADS)

    Xie, Luogang; Luo, Yin; Lin, Dongdong; Xi, Wenhui; Yang, Xinju; Wei, Guanghong

    2014-07-01

    Amyloid deposits are implicated in the pathogenesis of many neurodegenerative diseases such as Alzheimer's disease (AD). The inhibition of β-sheet formation has been considered as the primary therapeutic strategy for AD. Increasing data show that nanoparticles can retard or promote the fibrillation of amyloid-β (Aβ) peptides depending on the physicochemical properties of nanoparticles, however, the underlying molecular mechanism remains elusive. In this study, our replica exchange molecular dynamics (REMD) simulations show that fullerene nanoparticle - C60 (with a fullerene : peptide molar ratio greater than 1 : 8) can dramatically prevent β-sheet formation of Aβ(16-22) peptides. Atomic force microscopy (AFM) experiments further confirm the inhibitory effect of C60 on Aβ(16-22) fibrillation, in support of our REMD simulations. An important finding from our REMD simulations is that fullerene C180, albeit with the same number of carbon atoms as three C60 molecules (3C60) and smaller surface area than 3C60, displays an unexpected stronger inhibitory effect on the β-sheet formation of Aβ(16-22) peptides. A detailed analysis of the fullerene-peptide interaction reveals that the stronger inhibition of β-sheet formation by C180 results from the strong hydrophobic and aromatic-stacking interactions of the fullerene hexagonal rings with the Phe rings relative to the pentagonal rings. The strong interactions between the fullerene nanoparticles and Aβ(16-22) peptides significantly weaken the peptide-peptide interaction that is important for β-sheet formation, thus retarding Aβ(16-22) fibrillation. Overall, our studies reveal the significant role of fullerene hexagonal rings in the inhibition of Aβ(16-22) fibrillation and provide novel insight into the development of drug candidates against Alzheimer's disease.Amyloid deposits are implicated in the pathogenesis of many neurodegenerative diseases such as Alzheimer's disease (AD). The inhibition of

  6. Controlling adsorbate interactions for advanced chemical patterning

    NASA Astrophysics Data System (ADS)

    Saavedra Garcia, Hector M.

    -situ esterification results in the creation of subtle chemical and structural defects that promote molecular exchange reactions to go to completion. The complementary hydrolysis reaction can be employed to quench the reacted monolayer, significantly hindering further displacement. The generality of reversible lability was tested by applying the in-situ esterification reaction to the structurally distinct carboxyl-functionalized molecule 3-mercapto-1-adamantane-carboxylic acid. In addition to the studies of manipulating the interactions in self-assembled monolayers, materials with tunable optical and electronic properties were fabricated using atomic clusters as building blocks. It was shown that materials assembled from the same cluster motif, in this case As3-7 , can result in materials with band gaps that vary predictably between 1.09 to 2.08 eV. The size and highest occupied molecular orbital of the alkali metal counter-cation used in the assembly was shown to affect the band gap of the cluster-assembled solids. Furthermore, the dimensionality of the cluster-cluster interactions played a crucial role in determining the resulting properties. These results demonstrate how complex surface assemblies, or novel solid materials, can be fabricated by manipulating the interactions between the individual components within the assemblies, paving the way for the fabrication of next-generation devices and materials.

  7. 3-Bromopyruvate (3BP) a fast acting, promising, powerful, specific, and effective "small molecule" anti-cancer agent taken from labside to bedside: introduction to a special issue.

    PubMed

    Pedersen, Peter L

    2012-02-01

    Although the "Warburg effect", i.e., elevated glucose metabolism to lactic acid (glycolysis) even in the presence of oxygen, has been recognized as the most common biochemical phenotype of cancer for over 80 years, its biochemical and genetic basis remained unknown for over 50 years. Work focused on elucidating the underlying mechanism(s) of the "Warburg effect" commenced in the author's laboratory in 1969. By 1985 among the novel findings made two related most directly to the basis of the "Warburg effect", the first that the mitochondrial content of tumors exhibiting this phenotype is markedly decreased relative to the tissue of origin, and the second that such mitochondria have markedly elevated amounts of the enzyme hexokinase-2 (HK2) bound to their outer membrane. HK2 is the first of a number of enzymes in cancer cells involved in metabolizing the sugar glucose to lactic acid. At its mitochondrial location HK2 binds at/near the protein VDAC (voltage dependent anion channel), escapes inhibition by its product glucose-6-phosphate, and gains access to mitochondrial produced ATP. As shown by others, it also helps immortalize cancer cells, i.e., prevents cell death. Based on these studies, the author's laboratory commenced experiments to elucidate the gene basis for the overexpression of HK2 in cancer. These studies led to both the discovery of a unique HK2 promoter region markedly activated by both hypoxic conditions and moderately activated by several metabolites (e.g., glucose), Also discovered was the promoter's regulation by epigenetic events (i.e., methylation, demethylation). Finally, the author's laboratory turned to the most important objective. Could they selectively and completely destroy cancerous tumors in animals? This led to the discovery in an experiment conceived, designed, and conducted by Young Ko that the small molecule 3-bromopyruvate (3BP), the subject of this mini-review series, is an incredibly powerful and swift acting anticancer agent

  8. Optical Detection of Anomalous Nitrogen in Comets

    NASA Astrophysics Data System (ADS)

    2003-12-01

    studies will provide crucial information about the detailed composition of a much larger number of comets than hitherto possible and hence, more information about the primordial matter from which the solar system formed. A better understanding of the origins of the cometary material (in particular the HCN and CN molecules [3]) and the connection with heavier organic molecules is highly desirable. This is especially so in view of the probable rôle of comets in bringing to the young Earth materials essential for the subsequent formation of life on our planet . PR Photo 28a/03 : Comet LINEAR (C/2000 WM1) - direct image and UVES slit position. PR Photo 28b/03 : Part of the UVES spectrum of Comet LINEAR (C/2000 WM1) with CN-band. PR Photo 28c/03 : Identification of nitrogen-15 in the spectrum. Cometary material Knowledge of the abundance of the stable isotopes [2] of the light elements in different solar system objects provides critical clues to the origin and early evolution of these objects and of the system as a whole. In order to gain the best possible insight into the origins and formation of the niche in which we live, it is therefore important to determine such isotopic abundance ratios in as many members of the solar family as possible. This is particularly true for comets, believed to be carriers of well-preserved specimens of the pristine material from which the solar system was made, some 4,600 million years ago. However, the detailed study of cometary material is a difficult task. Measurements of isotopic ratios is an especially daunting undertaking, mainly because of the extreme weakness of the spectral signatures (emissions) of the less abundant species like carbon-13, nitrogen-15, etc.. Measurements of microwave emission from those atoms suffer from additional, inherent uncertainties connected to the much stronger emission of the more abundant species. Measurements in the optical spectral region thus take on particular importance in this context. However, it is

  9. 16th international conference on the physics of highly charged ions

    NASA Astrophysics Data System (ADS)

    Fritzsche, Stephan; Stöhlker, Thomas; Surzhykov, Andrey

    2013-09-01

    physicists. The conference was held in the Physics Lecture Hall at the New Campus of Heidelberg University. On the evening of 2 September, the day before the opening of HCI 2012, all participants were welcomed warmly at the foyer of this lecture hall, whose decorative glass front provides a view upon artificial ponds and water lilies at this time of the year. For many colleagues and delegates, this evening offered a hearty re-encounter with each other, along with wine and other beverages. The conference then opened on the morning of 3 September, and an exciting program was organized by the local committee with the help of the International Advisory Board, including 5 invited talks, 10 progress reports as well as 26 selected talks. In addition, more than 230 posters were presented in two sessions, with beer and brezels aside. On Tuesday evening, an exciting public lecture on Heavy ions in therapy and space was given by Marco Durante from the GSI Helmholtz Center and Technical University in Darmstadt. Moreover, many of the participants joined the guided tour through the old city of Heidelberg with its famous (ruins of the) castle, and several the Solar Boat Trip. On Thursday night, we all enjoyed the conference dinner with home-brewed beer and regional specialties at the 'Kulturbrauerei' in the historic center of Heidelberg. Finally, scientific tours were also organized to GSI Darmstadt and the Max-Planck Institute for Nuclear Physics in Heidelberg on the last day of the conference, and attracted much consideration. We here present the proceedings of this conference that contain a total of 104 contributions, including invited papers, progress reports and contributed papers. As previously, these papers are grouped into five categories. (1) Fundamental aspects, structure and spectroscopy. (2) Collisions with electrons, ions, atoms and molecules. (3) Interactions with clusters, surfaces and solids. (4) Interactions with photons, plasmas and strong field processes. (5) Production

  10. PREFACE: 14th International Conference on the Physics of Highly Charged Ions (HCI 2008)

    NASA Astrophysics Data System (ADS)

    Azuma, Toshiyuki; Nakamura, Nobuyuki; Yamada, Chikashi

    2009-07-01

    the morning of 1 September. In the evening we invited the foreign delegates to the Tokyo-EBIT laboratory and entertained them with sushi and YEBISU beer at the lab (YEBISU is a popular brand of beer in Japan and also the nickname of the Tokyo-EBIT project, Young Electron Beam Ion Source Unit). Cans of YEBISU beer also helped us to make the poster sessions lively, on the evenings of 2 and 4 September. The best poster of each session was selected by the vote of International Advisory Board, and two young scientists were awarded the prizes. On the afternoon of 3 September, we took an excursion to Lake Yamanaka near Mount Fuji for a conference outing. The conference dinner was then held at a hotel alongside Lake Yamanaka from where we really enjoyed the view of Mount Fuji. In the summer it is quite rare to have clear weather, but a teru-teru bozu (a Japanese paper doll with a wish for good weather) placed on the top page of the conference WEB site brought us clear skies for the dinner. About 200 scientists from 22 countries registered for the HCI2008. The number of invited talks was 18 and the contributed papers 206. These proceedings contain 9 invited talks and 107 contributed articles. Following the previous conference, they are grouped into the five categories of: (1) Fundamental aspects, structure and spectroscopy; (2) Collisions with electrons, ions, atoms and molecules; (3) Interactions with clusters, surfaces and solids; (4) Interactions with photons, plasmas and strong field processes, and (5) Production, experimental developments and applications. We are happy that the conference was completely successful, and this success owes much to the sponsors. We acknowledge the support from the Japan Society for the Promotion of Science (JSPS), The International Union of Pure and Applied Physics (IUPAP), Matsuo Foundation, Iwatani Naoji Foundation, CASIO Science Promotion Foundation, and The Society for Atomic Collision Research. The next International Conference on the

  11. EDITORIAL: The best of both worlds The best of both worlds

    NASA Astrophysics Data System (ADS)

    Demming, Anna

    2010-05-01

    This year marks 80 years since Chandrasekhara Venkata Raman was awarded the Nobel Prize for his investigations on the molecular scattering of light [1], work inspired during a trip to Europe by his first glimpse of the 'wonderful blue opalescence of the Mediterranean Sea' [2]. These studies led to the discovery of Raman scattering, now widely exploited for the unique spectral Raman 'fingerprint' associated with substances that facilitate their identification. However, one of the drawbacks of Raman spectroscopy has always been the low Raman scattering cross section, typically more than a 1000 times weaker than the Rayleigh scattering cross section, resulting in an extremely weak signal. Progress in nanotechnology revealed ways of enhancing Raman signals using metal nanoparticles, resulting in optical detection and spectroscopy at the level of a single molecule [3]. Surface plasmon resonances in metal nanoparticles have demonstrated great potential in a range of applications, including data storage, light generation, nonlinear optics, microscopy and biophotonics, and this has motivated many investigations aimed at optimising plasmonic properties. Researchers in Japan and China demonstrated how the self-assembly of gold nanoparticles can be used to tune plasmonic responses [4], and more recently researchers in America have demonstrated how nanocrescent structures can be tuned to respond in the infrared part of the electromagnetic spectrum, lending these nanostructures to applications in cellular imaging in vivo [5]. At the time that Nanotechnology was launched 20 years ago, nanoscale research had been galvanized by developments in scanning probe techniques that pushed microscopic resolutions to unprecedented scales, enabling people to `see' atoms for the first time. The intrinsic awe of such images and the potency of these investigative tools naturally drove further research into refining techniques in scanning, tunnelling and atomic force microscopy [6, 7]. However