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Objective To evaluate the role of recombinant human soluble Tim-3 (hTim-3-Fc) in regulating immune response.Methods Soluble hTim-3 was incubated with human macrophage cell line U 937, human T cell line Jurkat and normal human PBMC before cytokines secreted by or expressed in different immune cells were analyzed using ELISA , RT-PCR and Western-blotting, respectively.Results Soluble hTim-3 significantly promoted the activation of different immune cells.Our data showed that IL-8 secretion by U937 cells, IL-2 secretion by Jurkat cells , IL-2 and IFN-γsecretion by human PBMCs were all significantly increased .In addition , soluble hTim-3 significantly increased the IFN-α2 and IFN-β1 mRNA expression in U937, Jurkat and PBMCs and increased the phosphorylation of stat-1 in Jurkat and U937 cells.Conclusion Recombinant soluble hTim-3 can significantly promote the activation of immune cells in vitro, which shows its therapeutic potential .
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Objective To ascertain whether estrogen could induce B cell to produce interleukin(IL)-10. Methods C57BL/6 splenic B cells were purified by magnetic activated cell sorting(MACS)method,followed by estrogen treatment for 3 days. The secretion of IL-10 from cultured cell supernatant was tested by ELISA technique. The abundance of mRNA for IL-10、PD-L1 and RBM47 in B cells with estrogen treatment was tested by real-time PCR method. The intracellular IL-10 expression and the surface PD-L1 expression of treated B cells were tested by fluorescence activated cell sorting(FACS)method. And the expression of RBM47 in B cells by estrogen treatment was tested using Western blotting method. Results Estrogen could induce B cell to produce IL-10 in a dose-dependent manner. Estrogen treatment could increase the percentage of IL-10+B cells,the abundance of mRNA for IL-10,PD-L1 and RBM47 in B cells,as well as the expression of PD-L1 on B cell surface. Furthermore,our experimental result indicated the upreg?ulation of RBM47 expression in B cells by estrogen treatment. Conclusion Estrogen treatment in vitro can induce the upregulation of IL-10+regulatory B cells(Breg). Upregulation of RBM47 in the treated B cells might participate in this process by stabilizing IL-10 mRNA.
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Objective To examine whether Tim-3 plays a protective role in paraquat poisoning induced excessive immune response and tissue damage based on the critical roles of Tim-3 controlling inflammatory response.Methods A paraquat poisoning model was established in wild type and in Tim-3 transgenic C57BL/6 mice by intraperitoneal injection of paraquat (40 mg/kg) .In addition, C57BL/6 mice with paraquat poisoning were injected with Tim-3 soluble protein( sTim-3) or control protein to see the effect of Tim-3 blocking on the progression of paraquat poisoning.Samples were collected at 6 and 24 h after paraquat injection respectively and were examined for tissue damage, cytokine expression and paraquat metabolism.Results After paraquat poisoning, there was significantly attenuated tissue damage in the lungs and kidneys and decreased TNF-α,IL-6 and IL-1 beta expression in the PBMCs or in the serum from Tim-3 transgenic mice compared to wild type mice.The serum concentration of paraquat in Tim-3 transgenic mice was also significantly decreased.However, in sTim-3 treated paraquat poisoning mice, there was significantly increased cytokine expression and tissue damage compared to control protein treated mice.The in vitro data showed that Tim-3 signaling negatively regulated macrophages mediated inflammatory response.Conclusion Tim-3 plays a critical role in maintaining the homeostasis after paraquat poisoning. Further investigation on the regulatory roles of Tim-3 in inflammation will shed new light on the pathogenesis of paraquat poisoning and provide new therapeutic strategies.
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Objective To analyze retrospectively the death pattern, risk factors, and death time of 253 patients at the Respiratory Care Unit of General Hospital of PLA in order to improve care quality and reduce mortality.Methods The information of patients was extracted from the hospital information system ( HIS) , and then classified and calculated accord-ing to different time points.Results Between November and next March,the mortality rate was higher than in other months (P<0.05), accounting for 19.5%.Mortality of those admitted between 8∶01 and 9∶00 or between 23∶01 and 24∶00 was higher than at other times(P<0.05), accounting for 41.7%and 50.0%, respectively.There was statistically significant difference(P<0.01) in mortality between days of the week,with the highest on Saturday, accounting for 43.1%.Mortality on non-work days was higher than on workday(P<0.01), accounting for 38.3% and 13.2%, respectively.Mortality at off-hour was higher than at office time(8∶00-11∶30 and 14∶30-18∶00 on workday) (P<0.01), accounting for 31.3%and 5.2%, respectively.Logistic regression analysis showed that age, month of admission, and the hour of discharge were associated with the outcome.Conclusion The high mortality between November and next March may be related to the higher incidence of respiratory diseases in winter, air pollution and cold weather.High mortality is also significantly associ-ated with the care quality of the medical staff.
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Interferon ( IFN) plays an essential role in antiviral infection.Interferons are divided into different categories according to their structure and function.People have attached increasing importance to TypeⅠinterferon( IFN-Ⅰ) in light of its unusual antiviral mechanism.This review is intended to shed light on IFN-Ⅰ,including its antiviral function,signal pathway and regulation.
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Objective To develop a human Tim-3 specific monoclonal antibody and evaluate its biological activity and possible use in clinical diseases associated with dysregulated Tim-3 expression .Methods The BALB/c mice were immu-nized by conventional method, and positive clones were used to develop anti-human Tim-3 antibody, the binding and neutralization activities of which in vitro and in vivo were investigated.Results ①A monoclonal antibody (clone L3D) which could specifically bind to human Tim-3 protein in ELISA assay was obtained and the subtype of the monoclonal antibody was IgG2a .②Flow cytometry indicated that the monoclonal antibody could bind to Tim-3 expressed in human U937 cells.This antibody also showed a cross activity to mice′Tim-3.③The monoclonal antibody inhibited the apoptosis of THP1 cells induced by Gal-9, the ligand of Tim-3.④Injection of Tim-3 antibody exacerbated sepsis in mice as marked by the decreased survival rate and increased expression of pro-inflammatory cytokines .Conclusion An anti-human Tim-3 monoclonal antibody is successfully obtained.The excellent binding and neutralization activities of this antibody enable it to be widely used in clinical diseases associated with deregulated Tim-3 expression .
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As a new identified help T cell lineage different from Th1 and Th2 cells, Th17 cell has been found played important roles in the pathogenesis of autoimmunity and inflammatory disease. To further identify their roles, the differentiation and regulation of Th17 cells has been widely explored recently. Now it has been confirmed that TGF-beta, combined with IL-6 or IL-21, play critical roles in the differentiation of Th17 cells. While IL-23 mainly contribute in promoting the secretion of IL-17 and maintaining the function of Th17 cells. Corresponding with the Th1,Th2, and Treg cells, which has special transcription factors T-bet、GATA3、Foxp3 respectively, now it has been confirmed that ROR-?t(retinoid-related orphan receptors-?t) is the special transcription factor which specially regulate the differentiation of Th17 cells. Th17 cells function through their secreted pro-inflammatory cytokines, including IL-17A, IL-17F, IL-21, IL-22, IL-6, TNF-?. Among them IL-21,which act as a autocrine cytokine of Th17 cells, play critical roles in promoting the differentiation of Th17 cells while inhibiting the differentiation and function of Th1 and Treg cells. On the other hand, IL-2, which is obligatory for the growth of Th1,Th2,Treg and CD8+T cells, now has been found negatively regulate the differentiation of Th17 cells. In all, differentiation of Th17 and Treg,Th1 cells are exactly regulated in vivo, in which TGF-beta played critical roles. As both Th1 and Th17 cells participate in the pathogenesis of autoimmunity and inflammatory diseases, are they play synergistic roles or function at different time point or location? How TGF-? regulate Th17 and Treg cells?Can Th17 cells be used as a target for immune tolerance induction? All above questions will certainly be of continuing interest.
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To investigate the plasma MIP 1?and MCP 1 levels in rats with pulmonary fibrosis produced by bleomycin and preliminarily study the pathogenesis of the two chemokines in pulmonary fibrosis. The rats were randomly divided into 2 groups: normal control and pulmonary fibrotic group. Rats were killed on day 1, 3, 7, 14 and 28, and the plasma were collected .The solid phase sandwich enzyme linked immuno sorbent assay (ELISA) was used to assay the level of plasma MIP 1? and MCP 1. The results showed that the level of MIP 1? and MCP 1 in rats with pulmonary fibrosis were significantly higher than those in normal control ; plasma MCP 1 level was significantly correlated with plasma MIP 1?. It indicates that plasma MIP 1? and MCP 1 may be useful markers for monitoring the course of pulmonary fibrosis and they may reflect the clinical evidence of pulmonary fibrosis.
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CD59 antigen is a widely expressed cell surface glycosylphosphatidyl-inositol (GPI) anchored glycoprotein.It acts as an inhibitor to the assembly of the membrane attack complex of homologous complement,binds to CD2,and also transduces activation signals with T cells.In this report,a 396bp DNA fragment was amplified by RT-PCR method from the total RNA of Jurkat cells.The fragment was cloned into pUC18 and pUC19 plas-mids,and further sequenced by Sanger′s-dideory-mediated chain termination.The results showed that this cDNA fragment included 384bp open reading fragment and its sequence was identical to the published sequence encoding human CD59 antigen.Furthermore,the cDNA of CD59 was subcloned into retroviral vector pLXSN and transfec-ted into packaging cell line PA317 to generate stable virus-producing cell lines.Then,mouse thymotase cell line EL-4 and fibroblasts cell line NIH3T3 were infected with the virus resulting in stable expression of CD59 on the cell surface.The transfected cells were tested for their susceptibility to human complement-mediated cytolysis.It was found that the transfected cells expressing CD59 antigen were far less susceptible than the controls,indicating that the gene for CD59 can be expressed in xenotypic cells stably to confer protection against human serum complement.