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1.
Felix M. Behr Ammarina Beumer-Chuwonpad Natasja A. M. Kragten Thomas H. Wesselink Regina Stark Klaas P. J. M. van Gisbergen 《European journal of immunology》2021,51(1):151-166
Tissue-resident memory CD8+ T cells (TRM) localize to barrier tissues and mediate local protection against reinvading pathogens. Circulating central memory (TCM) and effector memory CD8+ T cells (TEM) also contribute to tissue recall responses, but their potential to form mucosal TRM remains unclear. Here, we employed adoptive transfer and lymphocytic choriomeningitis virus reinfection models to specifically assess secondary responses of TCM and TEM at mucosal sites. Donor TCM and TEM exhibited robust systemic recall responses, but only limited accumulation in the small intestine, consistent with reduced expression of tissue-homing and -retention molecules. Murine and human circulating memory T cells also exhibited limited CD103 upregulation following TGF-β stimulation. Upon pathogen clearance, TCM and TEM readily gave rise to secondary TEM. TCM also formed secondary central memory in lymphoid tissues and TRM in internal tissues, for example, the liver. Both TCM and TEM failed to substantially contribute to resident mucosal memory in the small intestine, while activated intestinal TRM, but not liver TRM, efficiently reformed CD103+ TRM. Our findings demonstrate that circulating TCM and TEM are limited in generating mucosal TRM upon reinfection. This may pose important implications on cell therapy and vaccination strategies employing memory CD8+ T cells for protection at mucosal sites. 相似文献
2.
Jamil Assreuy Fernando Q. Cunha Monica Epperlein Alberto Noronha-Dutra Catherine A. O'Donnell Foo Y. Liew Salvador Moncada 《European journal of immunology》1994,24(3):672-676
Murine macrophages can be activated to produce nitric oxide (NO) and superoxide and these two radicals can react to form peroxynitrite, a powerful oxidant which may be involved in parasite killing. We now show that murine macrophages activated with zymosan and interferon-γ (ZYM/IFN-γ) produced both superoxide (peaking 1–2 h after stimulation, then rapidly declining) and NO (barely detectable at 6 h, peaking by 24 h). Macrophages activated with ZYM alone produced only superoxide, while stimulation with lipopolysaccharide (LPS) and IFN-γ induced NO but not superoxide. Cells stimulated with ZYM/IFN-γ or LPS/IFN-γ killed Leishmania major to a similar degree, an effect that was completely blocked by the addition of N-iminoethyl-L -ornithine. However, macrophages stimulated with ZYM alone were unable to kill L. major. S-nitroso-acetyl-penicillamine, which release NO, was highly leishmanicidal when added directly to the parasites. 3-morpholino-sydnonimine hydrochloride which releases both NO and superoxide simultaneously, was also efficient at killing L. major and this cytotoxicity was greatly enhanced by the addition of superoxide dismutase. Finally, authentic peroxynitrite failed to induce any cytotoxic effect, even at a high concentration. Thus macrophages can produce either NO, superoxide or both, depending on the stimulus. However, the killing of L. major is dependent only on the production of NO. 相似文献
3.
Chronic antigenic stimulation leads to gradual accumulation of late-differentiated, antigen-specific, oligoclonal T cells, particularly within the CD8(+) T-cell compartment. They are characterized by critically shortened telomeres, loss of CD28 and/or gain of CD57 expression and are defined as either CD8(+) CD28(-) or CD8(+) CD57(+) T lymphocytes. There is growing evidence that the CD8(+) CD28(-) (CD8(+) CD57(+)) T-cell population plays a significant role in various diseases or conditions, associated with chronic immune activation such as cancer, chronic intracellular infections, chronic alcoholism, some chronic pulmonary diseases, autoimmune diseases, allogeneic transplantation, as well as has a great influence on age-related changes in the immune system status. CD8(+) CD28(-) (CD8(+) CD57(+)) T-cell population is heterogeneous and composed of various functionally competing (cytotoxic and immunosuppressive) subsets thus the overall effect of CD8(+) CD28(-) (CD8(+) CD57(+)) T-cell-mediated immunity depends on the predominance of a particular subset. Many articles claim that CD8(+) CD28(-) (CD8(+) CD57(+)) T cells have lost their proliferative capacity during process of replicative senescence triggered by repeated antigenic stimulation. However recent data indicate that CD8(+) CD28(-) (CD8(+) CD57(+)) T cells can transiently up-regulate telomerase activity and proliferate under certain stimulation conditions. Similarly, conflicting data is provided regarding CD8(+) CD28(-) (CD8(+) CD57(+)) T-cell sensitivity to apoptosis, finally leading to the conclusion that this T-cell population is also heterogeneous in terms of its apoptotic potential. This review provides a comprehensive approach to the CD8(+) CD28(-) (CD8(+) CD57(+)) T-cell population: we describe in detail its origins, molecular and functional characteristics, subsets, role in various diseases or conditions, associated with persistent antigenic stimulation. 相似文献
4.
Fleur S. Kleijwegt Diahann T. S. L. Jansen Josefine Teeler Antoinette M. Joosten Sandra Laban Tatjana Nikolic Bart O. Roep 《European journal of immunology》2013,43(1):85-92
Type 1 diabetes is a T‐cell‐mediated autoimmune disease in which autoreactive CD8+ T cells destroy the insulin‐producing pancreatic beta cells. Vitamin D3 and dexamethasone‐modulated dendritic cells (Combi‐DCs) loaded with islet antigens inducing islet‐specific regulatory CD4+ T cells may offer a tissue‐specific intervention therapy. The effect of Combi‐DCs on CD8+ T cells, however, remains unknown. To investigate the interaction of CD8+ T cells with Combi‐DCs presenting epitopes on HLA class I, naive, and memory CD8+ T cells were co‐cultured with DCs and proliferation and function of peptide‐specific T cells were analyzed. Antigen‐loaded Combi‐DCs were unable to prime naïve CD8+ T cells to proliferate, although a proportion of T cells converted to a memory phenotype. Moreover, expansion of CD8+ T cells that had been primed by mature monocyte‐derived DCs (moDCs) was curtailed by Combi‐DCs in co‐cultures. Combi‐DCs expanded memory T cells once, but CD8+ T‐cell numbers collapsed by subsequent re‐stimulation with Combi‐DCs. Our data point that (re)activation of CD8+ T cells by antigen‐pulsed Combi‐DCs does not promote, but rather deteriorates, CD8+ T‐cell immunity. Yet, Combi‐DCs pulsed with CD8+ T‐cell epitopes also act as targets of cytotoxicity, which is undesirable for survival of Combi‐DCs infused into patients in therapeutic immune intervention strategies. 相似文献
5.
Lorna Proudfoot Catherine A. O'Donnell Foo Y. Liew 《European journal of immunology》1995,25(3):745-750
Murine macrophages express high levels of inducible nitric oxide (NO) synthase and produce large amounts of nitric oxide when activated with interferon-γ and lipopolysaccharide in vitro. Nitric oxide is a mediator of a variety of biological functions including microbicidal activity against the protozoan parasite Leishmania species. Glycoinositolphospholipids (GIPL) are the predominant surface glycolipids in both developmental stages of Leishmania major. We report here that GIPL can inhibit the synthesis of NO in a time- and dose-dependent manner. In contrast, lipophosphoglycan, which is present in the promastigote stage did not inhibit NO synthesis. GIPL-treated macrophages also showed markedly reduced leishmanicidal activity. The majority of the inhibitory activity of GIPL was found within the alkylacylglycerol moiety of the GIPL molecule. These data, therefore, suggest that GIPL may contribute towards the survival of the parasite in the immune hosts. 相似文献
6.
Chong LK Aicheler RJ Llewellyn-Lacey S Tomasec P Brennan P Wang EC 《European journal of immunology》2008,38(4):995-1000
CD8hi CD57+ T cells have previously been described as effector memory T cells with minimal expansion capacity and high susceptibility to activation-induced cell death. In contrast, we demonstrate here that CD8hi CD57+ T cells are capable of rapid expansion using multiple techniques including [(3)H]thymidine uptake, flow cytometric bead-based enumeration and standard haemocytometer counting. Previous reports can be explained by marked inhibition of activation-induced expansion and increased 7-amino-actinomycin D uptake by CD8hi CD57+ T cells following treatment with CFSE, a dye previously used to measure their proliferation, combined with specific media requirements for the growth of this cell subset. The ability of CD8hi CD57+ T cells to further differentiate is highlighted by a distinct cytokine profile late after activation that includes the unexpected release of high levels of interleukin 5. These data indicate that CD8hi CD57+ T cells should not be considered as "end-stage" effector T cells incapable of proliferation, but represent a highly differentiated subset capable of rapid division and exhibiting novel functions separate from their previously described cytotoxic and IFN-gamma responses. 相似文献
7.
Establishment of resistance to Leishmania major infection in susceptible BALB/c mice requires parasite-specific CD8+ T cells 总被引:8,自引:0,他引:8
Muller Ingrid; Pedrazzini Thierry; Kropf Pascale; Louis Jacques; Milon Genevieve 《International immunology》1991,3(6):587-597
Although CD4+ T cells are generally accepted to be responsiblefor the determination of resistance to infection in experimentalmurine cutaneous leishmanlasis, a contribution of CD8+ lymphocytesto immunity can be demonstrated under certain well-defined conditions.Normally highly susceptible BALB/c mice can be rendered resistantto infection with Leishmania major promastigotes by a singleinjection of monoclonal anti-CD4 antibodies at the beginningof infection. Mice treated in such a way can heal their primarycutaneous lesions and acquire immunity to subsequent challengeinfection. Both the resolution of the primary infection andthe induced state of immunityto reinfection in these mice isshown to be dependent upon the anti-leishmanial effector functionsof CD8+ T cells. Furthermore, in contrast to control infectedBALB/c mice, which are unable to mount a delayed-type hypersensitivity(DTH) response to viable parasites, mice cured as a result oftreatment with anti-CD4 antibodies in vivo exhibit a strongDTH response, which can be significantly reduced by injectionof either anti-CD4 or anti-CD8 monoclonal antibodies prior toantigenic challenge with viable promastigotes. Moreover, increasednumbers of specific CD8+ T cells, able to transferLeishmania-specificDTH responses, were found in lymphold organs of BALB/c micerendered resistant to infection by immunointervention with anti-CD4monoclonal antibodies at the beginning of infection. Neutralizationin vivo of interleukin 4 during the course of infection in BALB/cmice also enables these otherwise susceptible mice to resolvetheir cutaneous lesions and to decrease the parasite burdenin infected tissues. CD8+ T cells are required for both of thesebeneficial effects. Taken together, these results indicate thatin the immune BALB/c mouse, as in the normally resistant CBAmouse, CD8+ lymphocytes are involved in the elimination of L.major and in the establishment and maintenance of immunity againstinfection with this parasite. 相似文献
8.
Barbara Misme-Aucouturier Adel Touahri Marjorie Albassier Francine Jotereau Patrice Le Pape Nidia Alvarez-Rueda 《Human immunology》2019,80(12):999-1005
Although multiple immune cells participate in the innate and adaptive immune response against Candida albicans, the elucidation of cellular and inflammation kinetics may be a promising strategy to decipher events propitious to infection eradication. We used an in vitro Candida-human leucocyte coculture approach to study the dynamics of rare CD4+CD8+ double positive T lymphocytes (DP T) produced in response to this fungus. Our results highlight the presence of two phenotypically distinct subsets of DP T cells: CD4hiCD8lo and CD4loCD8hi, and that the different ratio of these cells correlates with infection outcome. The ratio of CD4hiCD8lo over CD4loCD8hi by day 6 was significantly higher in controlled infections and decreased when infection persisted due to a significant increase in the proportion of CD4loCD8hi. When infection was controlled, CD4hiCD8lo T cells secreted IFNγ, TNFα, IL-4 and IL-10 cytokines two days after challenge. By day 2, under conditions of persistent infection, CD4hiCD8lo and CD4loCD8hi T cells secreted significant levels of IL-4 and IL-10, respectively, compared to uninfected cultures. Frequency kinetics and original cytokine profiles detailed in this work indicate that DP T cells could participate in the adaptive immune response to C. albicans. 相似文献
9.
Heike Thüring Steffen Stenger Daniela Gmehling Martin Rllinghoff Christian Bogdan 《European journal of immunology》1995,25(12):3229-3234
Nitric oxide (NO) generated by the inducible isoform of nitric oxide synthase (iNOS) is implicated in a number of immunological processes including killing of intracellular parasites, suppression of T cell proliferation, production of cytokines and destruction of tissue in autoimmune diseases. Considering that cytokine-activated mouse macrophages, fibroblasts and endothelial cells are potent producers of NO, we investigated whether T cells, as central participants in immune responses, can also be activated for the release of NO. Neither thymocytes nor type 1 or type 2 T helper cell clones generated significant amounts of nitrite (the stable end product of NO in culture supernatants) when stimulated by T cell mitogens, cytokines or antigen in the presence of irradiated antigen-presenting cells. Similarly, T cells freshly isolated from mice acutely infected with the intracellular pathogen Leishmania major did not produce NO upon restimulation in vitro. The lack of NO production was not due to the expression of enzymatically inactive iNOS, as we were unable to detect any iNOS protein in activated T helper clones or in freshly isolated T cells from infected mice by Western (protein) blot analysis. Finally, we tested whether iNOS expression in T cells might be restricted to a minor subpopulation and therefore only detectable on a single cell level. After immunofluorescence staining of lymph node or spleen cells from infected mice with antibodies against iNOS, F4/80- or Thy-1-antigen, macrophages, but no T cells, were found to express iNOS. Thus, we have no evidence that activated T helper cell clones or T cells from L. major-infected mice are high producers of NO. 相似文献
10.
11.
Christine Claus Jrg Schlaak Maria Dittmayer Karl-Hermann Meyer Zum Büschenfelde Wolfgang Dippold 《European journal of immunology》1994,24(5):1208-1212
The ganglioside GD3 has been described as a membrane component of human T cells which is involved in T cell growth. In the present study the activating function of GD3 for human CD4+ and CD8+ T cells was analyzed by five different monoclonal antibodies (mAb) directed against the GD3 molecule. Three mAb U5, Z21 and R24 induced strong proliferation of peripheral blood mononuclear cells and purified CD8+ and CD4+ T cells of normal donors containing less than 5% CD16+ natural killer (NK) cells. In contrast to CD4+ T cells, CD8+ T cells proliferated only weakly in the presence of 15% CD16+ NK cells. The proliferative response of purified CD4+ and CD8+ T cells (<5% NK cells) correlated with the antibody-dependent induction of integral and soluble interleukin-2 (IL-2) receptors and was reduced to 20% by an anti-IL-2 receptor antibody. Our results show, that the GD3 molecule represents an activation molecule for both CD4+ and CD8+ T cells and that CD16+ NK cells selectively inhibit anti-GD3 antibody-induced proliferation of CD8+ T cells. 相似文献
12.
M. F. Macedo G. Porto M. Costa C. P. Vieira B. Rocha E. Cruz 《Clinical and experimental immunology》2010,159(3):363-371
Low CD8+ T lymphocyte numbers have long been described in hereditary haemochromatosis (HH). Recently, two conserved haplotypes localized near the microsatellite D6S105 at the major histocompatibility complex (MHC) class I region were described predicting the clinical expression of HH and the CD8+ T lymphocyte numbers. The A‐A‐T haplotype was associated with a severe clinical expression of HH and low CD8+ T lymphocyte numbers, while the G‐G‐G haplotype was associated with a milder clinical expression of HH and high CD8+ T lymphocyte numbers. As CD8+ T lymphocytes are a very heterogeneous population, in this study we analysed the CD8+ subpopulations of naive, central memory (TCM) and effector memory (TEM), and further subsets of CD8+ TEM cells in 47 HH patients and 68 controls. In addition, association studies were conducted between the conserved haplotypes and the CD8+ T cell subpopulations in HH. Variations of the numbers of naive and central memory cells with age were similar between HH patients and controls. For TEM cells and the TEM CD27‐CD28‐ subset no effect of age was observed in HH [R2 = 0·001, not significant (n.s.) and R2 = 0·01, n.s., respectively] contrasting with the increasing of these subpopulations with age in controls (R2 = 0·09, P = 0·017 and R2 = 0·22, P = 0·0005, respectively). Interestingly, patients homozygous for the A‐A‐T haplotype have lower numbers of CD8+ TEM cells due especially to lower numbers of TEM CD27‐CD28‐ (0·206 ± 0·119 and 0·066 ± 0·067 × 106 cells/ml, respectively) than patients carrying the G‐G‐G haplotype (0·358 ± 0·195 and 0·246 ± 0·202 × 106 cells/ml, respectively). This may suggest an inability of HH patients to differentiate the CD8+ T cells into the most mature phenotype. 相似文献
13.
《Human immunology》2016,77(7):576-579
PurposeTo characterize the peripheral immunity and immunity response of patients with sporotrichosis, in this study we determined the lymphocyte subsets in the peripheral blood of Chinese patients with sporotrichosis.MethodsIn this retrospective study, peripheral blood was collected from 69 sporotrichosis patients (37, fixed cutaneous form; 32 lymphocutaneous) and 66 healthy controls. Lymphocyte subsets were analyzed using flow cytometry.ResultsCompared to controls, the percentage of CD8+ T cells was lower in sporotrichosis patients. The percentage of CD8+ T cells in peripheral blood tended to become lower with disease duration and disease severity, although the difference was not statistically significant for either acute, subacute and chronic patients or fixed cutaneous and lymphocutaneous patients.ConclusionOur data indicate that the decrease of CD8+ T cells in peripheral blood of patients with sporotrichosis is associated with disease severity, although the difference was not statistically significant for either duration or clinical forms of the disease. Combining antifungal agents and immunomodulators in patients with long disease duration and lymphocutaneous may be more beneficial than antifungal monotherapy. 相似文献
14.
Fernando Q. Cunha Jamil Assreuy Damo Xu Ian Charles Foo Y. Liew Salvador Moncada 《European journal of immunology》1993,23(6):1385-1388
Murine macrophages express high levels of nitric oxide (NO) synthase and produce large amounts of NO when stimulated with interferon-y plus lipopolysaccharide in vitro. The expression of NO synthase peaks at 12 h after stimulation and declines rapidly to the background level by 72 h. These macrophages can be repeatedly reactivated to express similar levels of NO synthase. The reactivation is not due to newly divided cells since peritoneal macrophages which do not divide in vitro and J774 cells cultured in the presence of colchicine can also be restimulated to express NO synthase. The reactivation is accompanied by re-expression of NO synthase mRNA, as assessed by polymerase chain reaction analysis. Furthermore, the reactivated macrophages are fully capable of killing the intracellular protozoan parasite Leishmania major. 相似文献
15.
Zhanwei Wang Xi Yang Junjun Shen Jiamin Xu Mingyue Pan Jin Liu Shuwen Han 《Human immunology》2021,82(4):279-287
BackgroundBreast carcinoma is one of the most common tumors in women. The immune microenvironment, especially T cell infiltration, is related to the occurrence and prognosis of breast carcinoma.ObjectiveThis study investigated the gene expression patterns associated with tumor-infiltrating CD4+ and CD8+ T cells in invasive breast carcinomas.MethodsThe gene expression data and corresponding clinical phenotype data from the Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) were downloaded. The stromal and immune score were calculated using ESTIMATE. The differentially expressed genes (DEGs) with a high vs. low stromal score and a high vs. low immune score were screened and then functionally enriched. The tumor-infiltrating immune cells were investigated using the Cibersort algorithm, and the CD4+ and CD8+ T cell-related genes were identified using a Spearman correlation test of infiltrating abundance with the DEGs. Moreover, the miRNA-mRNA pairs and lncRNA-miRNA pairs were predicted to construct the competing endogenous RNAs (ceRNA) network. Kaplan-Meier (K-M) survival curves were also plotted.ResultsIn total, 478 DEGs with a high vs. low stromal score and 796 DEGs with a high vs. low immune score were identified. In addition, 39 CD4+ T cell-related genes and 78 CD8+ T cell-related genes were identified; of these, 14 genes were significantly associated with the prognosis of BRCA patients. Moreover, for CD4+ T cell-related genes, the chr22-38_28785274-29006793.1–miR-34a/c-5p–CAPN6 axis was identified from the ceRNA network, whereas the chr22-38_28785274-29006793.1–miR-494-3p–SLC9A7 axis was identified for CD8+ T cell-related genes.ConclusionsThe chr22-38_28785274-29006793.1–miR-34a/c-5p–CAPN6 axis and the chr22-38_28785274-29006793.1–miR-494-3p–SLC9A7 axis might regulate cellular activities associated with CD4+ and CD8+ T cell infiltration, respectively, in BRCA. 相似文献
16.
Dass S. Vinay Chang H. Kim Beom K. Choi Byoung S. Kwon 《European journal of immunology》2009,39(6):1552-1563
Previously, we showed that CD11c defines a novel subset of CD8+ T cells whose in vivo activity is therapeutic for arthritis; however, the mechanisms directing their development, identity of their precursors, and basis of their effector function remain unknown. Here, we show that the novel subset develops from CD11csurface?CD8+ T cells and undergoes robust expansion in an antigen‐ and 4‐1BB (CD137)‐dependent manner. CD11c+CD8+ T cells exist in naïve mice (<3%) with limited suppressive activity. Once activated, they suppress CD4+ T cells in vivo and in vitro. Suppression of CD4+ by CD11c+CD8+ T cells is related to an increase in IDO activity induced in competent cells via the general control non‐derepressible‐2 pathway. CD11c+CD8+ T cells are refractory to the effect of IDO but constrict in a novel 1‐methyl D ,L ‐tryptophan‐dependent mechanism resulting in reversal of their suppressive effects. Thus, our data uncover, for the first time, the origin, development, and basis of the suppressive function of this novel CD11c+CD8+ T‐cell subpopulation that has many signature features of Treg. 相似文献
17.
CD8 lymphocytosis in primary cytomegalovirus (CMV) infection of allograft recipients: expansion of an uncommon CD8+ CD57- subset and its progressive replacement by CD8+ CD57+ T cells. 总被引:2,自引:2,他引:2
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M Labalette F Salez F R Pruvot C Noel J P Dessaint 《Clinical and experimental immunology》1994,95(3):465-471
Allograft recipients undergoing cytomegalovirus infection present increased proportions of circulating CD8+ lymphocytes. A longitudinal study of 11 kidney and five liver allograft recipients with primary CMV infection but no other etiological factor of graft dysfunction revealed selective imbalances of peripheral blood CD8+ T cell subsets. Initially, CMV viraemia is associated with elevated CD8+bright T cell numbers and T cell activation. Activation markers fall to normal when viral cultures become negative (before the end of the first month). During the second to sixth month, most (12/16) patients keep up high CD8+ T cell counts (1050-2900 CD8+ cells/mm3), comprising an uncommon CD8+ T cell subset, as 45-73% of CD8+bright lymphocytes were CD3+ and TCR alpha beta+, but were not stained by anti-CD28, CD11b, CD16, CD56, and CD57 antibody. Unexpectedly, CD8+CD57+ T cells, a hallmark of CMV infection, do not appear until the second to sixth month of primary CMV infection, and their numbers increase progressively thereafter. They become the predominant CD8+ T cell subset after 6 months of infection and their persistence for several (up to 4) years is strongly correlated (r = 0.87) with expansion of CD8+ cells. By analysis with MoAbs, there was no bias towards the use of particular TCR-V beta gene families at any time of primary CMV infection. Persistence of CD8 lymphocytosis is thus directly related to the rate of expansion of an uncommon CD8+CD57- subset and its progressive replacement by CD8+CD57+ T cells that are chronically elicited by CMV. 相似文献
18.
目的 探讨小鼠脾脏CD8 T细胞的免疫磁珠负性分选方法,并对分选后所得细胞进行纯度、活力及功能检测.方法 以免疫磁珠负性分选法从小鼠脾脏细胞中分离CD8 T细胞,流式细胞术检测所得细胞的纯度,台盼蓝检测细胞活力并用ConA刺激检测增殖能力. 结果 经过流式细胞仪测定免疫磁珠负性分选后的小鼠脾脏CD8 T细胞纯度达到(91.6±3.6)%,台盼兰染色细胞活力为(94.9±3.2)%,ConA刺激72 h后有(56.3±1.7)%的细胞增殖.结论 免疫磁珠负性分选法能够分选出高纯度的CD8 T细胞,并且不影响分选靶细胞的细胞活力和功能. 相似文献
19.
Saied Mirshahidi Aslihan Turhan A. Kevser Pi
kin Turgut Imir 《Immunology letters》1998,60(2-3):189-192
Nitric oxide (NO) and IL-12 are important mediators of the immune response to Leishmania major. In this study, the effects of L. major promastigotes, crude antigenic fraction (CAF) and its subfractions on NO production and IL-12 secretion by BALB/c mice peritoneal macrophages is investigated. The subfractions of CAF, namely, fractions 1, 2 and 3, that were in the molecular weight range of 97.4–66, 66–45 and below 45 kDa, respectively, were separated by SDS-PAGE. NO production was determined by using Griess reagent and IL-12 was measured by ELISA. It was found that NO production was stimulated by promastigotes but not by CAF or its subfractions. IL-12 secretion was stimulated by promastigotes, CAF and fraction 1 while fractions 2 and 3 did not have any effect. 相似文献
20.
目的 探讨表面受体CD244在活动性肺结核患者CD8+T细胞中的功能.方法 密度梯度离心法提取活动性肺结核患者和健康对照者的外周血单个核细胞,通过流式细胞术检测CD244在CD3+ CD8+细胞中的表达;通过细胞内染色方法检测CD244与细胞因子IFN-γ和TNF-α表达的关系.结果 CD244在活动性肺结核患者CD8+T细胞表达强度显著高于健康对照者(P=0.0003);复治肺结核患者的CD244表达强度显著高于新发肺结核患者(P=0.0011);CD244-细胞表达IFN-γ比例显著高于CD244+细胞(P=0.0013);CD244-细胞表达TNF-α比例显著高于CD244+细胞(P =0.0016).结论 CD244抑制活动性肺结核患者CD8+T细胞的细胞因子分泌表达. 相似文献