CD4^＋CD25^＋调节性T细胞在维持小鼠肝脏移植自发性免疫耐受状态中的作用

目的 探讨CD4^＋CD25^＋调节性T细胞在维持小鼠肝脏移植免疫耐受状态中的作用。方法 进行小鼠原位肝脏移植,诱导出移植免疫耐受后,向受体注射抗CD25抗体（PC61）以去除CD4^＋CD25^＋T细胞,检测受体内CD4^＋CD25^＋T细胞数量及叉状头／翅膀状螺旋转录因子（Foxp3）的表达以确定CD4^＋CD25^＋T细胞完全被清除,同时观察受体生存时间。结果与同种同系小鼠肝脏移植结果相似,同种异系肝脏移植小鼠的生存时间亦均超过70d。移植免疫耐受诱导后,PC61不同注射方案均能完全去除受体小鼠肝脏、脾脏及血液中的CD4^＋CD25^＋T细胞,且移植肝脏中Foxp3mRNA的表达也明显降低,表明完全去除了CD4^＋CD25。调节性T细胞,但肝脏移植动物生存时间并未受到影响。结论CD4^＋CD25^＋调节性T细胞对于小鼠肝脏移植自发性免疫耐受的维持并非必需。     

CD4+CD25+调节性T细胞对小鼠肝脏移植自发性免疫耐受的影响

目的 研究CD4+CD25+调节性T细胞在诱导自发性肝脏免疫耐受中的作用.方法 向受体和供体注射抗CD25抗体(PC61)后进行小鼠原位肝脏移植,观测其生存时间.术后20～30 d切取移植肝脏行HE染色,同时观察CD4+CD25+T细胞对CD4+T细胞和CD8+T细胞功能的影响.结果 去除受体而不是供体小鼠的CD4+CD25+T细胞可以导致肝移植排斥反应.而且,去除CD4+CD25+T细胞使移植物的白细胞浸润明显增多,组织损伤加重.同时,去除CD4+CD25+T细胞导致CD4+T细胞的增殖活性和CD8+T细胞的细胞毒活性明显增强.结论 受体来源的CD4+CD25+调节性T细胞在小鼠肝脏移植免疫耐受诱导中起重要作用.

Abstract：

Objective To examine the contribution of CD4+ CD25+ regulatory T cells to liver transplant tolerance. Methods After injection of anti-CD25 monoclonal antibody (mAb, PC61), mouse orthotopic liver transplantation was performed and survivals were determined. The paraffin-embedded sections of hepatic allografts were cut and stained with hematoxylin and eosin (HE). Furthermore, the effect of CD4+ CD25+ regulatory T cells on proliferative response of CD4+ T cells and cytotoxicity of CD8+ T cells was examined by depleting these regulatory T cells. Results Depletion of these cells in the recipients but not in the donors before liver transplantation caused rejection. Histological analyses of hepatic allografts with PC61 treatment showed extensive leukocyte infiltration and tissue destruction, whereas those in the control group showed minimal changes. Moreover, elimination of CD4+CD25+ T cells resulted in the enhancement of both proliferative response of CD4+ T cells and cytotoxicity of CD8+ T cells against donor-type alloantigen. Conclusions These results suggest that CD4+CD25+ regulatory T cells were important for tolerance induction to hepatic allografts.     

CD4+CD25+调节性T细胞对同种胰岛移植免疫耐受的影响

目的 观察体外分离的CD4+CD25+调节性T细胞对同种胰岛移植免疫耐受的影响.方法 免疫磁珠法分离CD4+CD25+调节性T细胞,体外试验观察其对CD4+CD25-T细胞增殖的影响.将数量达1×106的CD4+CD25+调节性T细胞回输胰岛移植受体,对比其对移植物存活的影响.结果 分离的CD4+CD25+调节性T细胞体外试验可明显抑制CD4+CD25-T细胞的增殖.单纯胰岛移植组移植物物存活期为(5.57±0.79)d,回输受体CD4+CD25+调节性T细胞数量1×106、2×106时,胰岛移植物存活时间分别为(15.29±2.29)d和(25.43±2.30)d(P《0.01).CD4+CD25+调节性T细胞回输胰岛移植受体可显著延长移植物存活期,诱导免疫耐受的作用为剂量依赖性.结论 CD+CD25+调节性T细胞体外、体内试验可抑制效应性T细胞功能,诱导胰岛移植免疫耐受.     

CD4+CD25+调节性T细胞与移植免疫耐受

CD4^＋CD25^＋调节性T细胞是一类具有特殊免疫调节功能的T细胞亚群,它所介导的免疫抑制在移植免疫耐受的诱导和维持中起关键作用。本文对近年来CD4^＋CD25^＋调节性T细胞的作用机制及免疫耐受等方面的研究进行了综述。     

全身照射预处理供体对异基因大鼠肝移植的作用及对受体内CD4~+CD25~+调节性T细胞的影响

目的 探讨全身照射(TBI)预处理诱导大鼠肝移植术后急性排斥反应的发生机制,及CD4~+ CD25~+调节性T细胞的变化在诱导免疫耐受中的作用.方法 以雄性Lewis、DA大鼠为供、受体,随机分为正常对照组、同种肝移植组、自发免疫耐受组、急性排斥反应组.观察各组受体的生存时间及生存率,检测受体术后外周血中ALT、TB含量、Foxp3~+ CD4~+ CD25~+ 调节性T细胞和T细胞亚群上GITR的表达,检测受体术后第14天移植肝的病理变化和受体脾脏CTL杀伤活性.结果 自发免疫耐受组,术后经历短暂排斥反应最终获得免疫耐受并长期存活.急性排斥反应组,在术后第17～21天死亡,与其他组相比,外周血血清中ALT、TB含量明显升高,而Foxp3~+ CD4~+ CD25~+调节性T细胞比例明显降低.TBI预处理大鼠供肝致受体外周血中CD3~+ CD4~+ T细胞上GITR表达降低,CD3~+CD8~+T细胞上GITR表达增加,提高CTL的杀伤活性.结论 通过TBI清除供体大鼠肝移植物中携带的旁路淋巴细胞,致受体外周血中Foxp3~+ CD4~+ CD25~+调节性T细胞表达降低,而使CD3~+ CD8~+T细胞上GITR表达增加,共同诱导大鼠肝移植术后急性排斥反应发生和耐受障碍.     

CD4+CD25+调节性T细胞与免疫耐受的研究进展

CD4+CD25+调节性T细胞的主要功能是抑制自身反应性T细胞,其在维持机体T细胞内环境稳定,调节和保持对自身抗原耐受之间的平衡以及移植免疫耐受方面具有重要作用.本文主要就CD4+CD25+调节性T细胞的功能、作用机制以及免疫抑制药物对调节性T细胞的影响等研究进展进行综述.     

树突状细胞和CD4+CD25+调节性T细胞在免疫耐受中的作用及关系

诱导免疫耐受具有高效、低毒、经济等优点,在器官移植中有着极其重要的意义.在建立免疫耐受中,树突状细胞(DC)起到克隆清除、克隆无能、表达T细胞抑制因子、选择性激活辅助T细胞和诱导调节性T细胞尤其是CD4+CD25+调节性T细胞的产生等作用.而CD4+CD25+调节性T细胞主要以DC为作用靶点,影响其分化成熟,抑制DC向...     

CD4+CD25+调节性T细胞与免疫耐受的研究进展

CD4 CD25 调节性T细胞的主要功能是抑制自身反应性T细胞,其在维持机体T细胞内环境稳定,调节和保持对自身抗原耐受之间的平衡以及移植免疫耐受方面具有重要作用。本文主要就CD4 CD25 调节性T细胞的功能、作用机制以及免疫抑制药物对调节性T细胞的影响等研究进展进行综述。     

CD4+CD25+调节性T细胞与免疫耐受的研究进展

CD4＋CD25＋调节性T细胞的主要功能是抑制自身反应性T细胞,对于维持机体T细胞内环境的稳定,调节和保持对自身抗原耐受之间的平衡以及移植免疫耐受具有重要作用。本文主要就CD4＋CD25＋调节性T细胞的功能和作用机制以及免疫抑制药物对其的影响等研究进展进行综述。     

地西他滨诱导体内Foxp3基因表达上调延长心脏移植小鼠的存活时间

目的 探讨甲基转移酶抑制剂地西他滨诱导体内叉状头螺旋转录因子(Foxp3)基因表达延长同种心脏移植小鼠存活时间的作用及其机制.方法 以经丝裂霉素处理的Balb/c小鼠和C57BL/6小鼠脾细胞作为刺激细胞,未经丝裂霉素处理的C57BL/6小鼠脾细胞作为反应细胞,进行体外单向混合淋巴细胞培养,观察地西他滨对培养体系中CD4+CD25+调节性T淋巴细胞(Treg细胞)比例的影响.分别以Balb/c小鼠和C57BL/6小鼠作为供、受者,建立同种小鼠腹部异位心脏移植模型.实验组受鼠术后1～3 d经尾静脉注射地西他滨(1.5 mg/kg),同种对照组受鼠术后1～3 d经尾静脉注射等体积生理盐水.监测两组移植心存活时间,检测受鼠外周血CD4+ CD25+ Treg细胞比例及Foxp3 mRNA的表达,观察移植心组织病理学变化.结果 地西他滨能够上调体外同种混合淋巴细胞反应体系中CD4+ CD25+Treg细胞的水平.同种对照组和实验组移植心脏中位存活时间分别为7和11d,实验组较对照组明显延长(P＜0.01).与同种对照组相比,实验组CD4+ CD25+ Treg细胞比例和Foxp3 mRNA的表达均明显升高(P＜0.01);移植心肌炎症细胞浸润的程度明显减轻.结论 地西他滨能够诱导同种心脏移植小鼠体内Foxp3基因的表达,从而明显减轻急性排斥反应,延长移植心存活时间,其机制可能与Foxp3表达能够诱导CD4+ CD25+ Foxp3+ Treg细胞的增殖和分化密切相关.     

Acceleration of apoptosis in CD4+CD8+ thymocytes by rapamycin accompanied by increased CD4+CD25+ T cells in the periphery

BACKGROUND: Rapamycin (Rapa) is an immunosuppressant that is used in patients and animal models to control allograft rejection. Its mechanisms of action are not fully understood. In this article, the authors have investigated the effects of therapeutic doses of Rapa on both thymic and peripheral T-cell populations in the adult rat. METHODS: The therapeutic dosage of Rapa was optimized using cardiac transplantation between LEW and DA rats. Thymic morphology was assessed by hematoxylin-eosin staining. Flow cytometric analysis was performed to analyze T-cell phenotype and apoptosis. T-cell receptor (TCR)-mediated T-cell responsiveness was evaluated by 3[H]-thymidine deoxyribose incorporation. RESULTS: Rapa induced atrophy in the thymus but not in peripheral lymphoid organs. Moreover, fibrosis occurred in thymus that was long-lasting after Rapa withdrawal. In animals treated with Rapa, there was a significant reduction in CD4+CD8+ thymocytes caused by accelerated apoptosis, whereas CD4-CD8-, CD4+CD8-, and CD8+CD4- populations remained unaffected. In contrast, the cellularity of the periphery lymphoid organs was not altered. Within the CD4+ thymocyte population, CD4+CD25+ thymocytes were resistant to Rapa-accelerated apoptosis, and in the periphery, the ratio of CD4+CD25+ to CD4+CD25- T cells was increased. Notably, the peripheral CD4+CD25+ T cells were hyporesponsive to TCR-mediated activation. CONCLUSIONS: The resistance of the peripheral CD4+CD25+ T cells to Rapa treatment might contribute to its immunosuppressive action. The long-term effects of Rapa on thymus atrophy and thymocyte development requires consideration with respect to its clinical application.     

CD19+CD5+ B cells in primary IgA nephropathy

The source of IgA and the mechanism for deposition of IgA in the mesangium remain unknown for primary IgA nephropathy. Because CD19(+)CD5(+) B cells are important producers of IgA and contribute to several autoimmune diseases, they may play an important role in IgA nephropathy. In this study, flow cytometry, quantitative PCR, and confocal microscopy were used to assess the frequency, distribution, Ig production, CD phenotypes, cytokine production, and sensitivity to apoptosis of CD19(+)CD5(+) B cells in the peripheral blood, peritoneal fluid, and kidney biopsies of 36 patients with primary IgA nephropathy. All patients with IgA nephropathy were significantly more likely to have CD19(+)CD5(+) B cells in the peripheral blood, peritoneal fluid, and kidney biopsies than were five control subjects and 10 patients with active systemic lupus erythematosus. The 33 patients who had IgA nephropathy and responded to treatment demonstrated a significant decrease in CD19(+)CD5(+) B cells in the peripheral blood, peritoneal fluid, and kidney (all P < 0.01). In the three patients who had IgA nephropathy and did not respond to treatment, the frequency of CD19(+)CD5(+) B cells did not change. CD19(+)CD5(+) B cells isolated from patients with untreated IgA nephropathy expressed higher levels of IgA, produced more IFN-gamma, and were more resistant to CD95L-induced apoptosis than cells isolated from control subjects and patients with lupus; these properties reversed with effective treatment of IgA nephropathy. In conclusion, these results strongly suggest that CD19(+)CD5(+) B cells play a prominent role in the pathogenesis of primary IgA nephropathy.     

肝癌、肝硬化组织中CD3、CD57、CD20细胞数量与临床病理表现及预后的关系

目的探讨CD3、CD57、CD20细胞在原发性肝细胞癌(HCC)、癌旁、肝硬化及正常肝组织中的数量及意义.方法HCC 60例,单纯性肝硬化62例,正常肝组织23例,以免疫组化SP法进行CD3、CD57、CD20染色,对阳性细胞数进行定量分析并与临床资料进行相关探讨.结果(1)各组CD3+细胞平均数从高到低为癌旁组织、癌组织、肝硬化组织、正常肝组织(P＜0.05);各组CD57+细胞平均数从高到低为癌组织、癌旁组织、正常肝组织、肝硬化组织(P ＜0.05);各组CD20+细胞平均数从高到低为癌组织、癌旁组织、肝硬化组织、正常肝组织(P ＜0.01).(2)HCC中CD3+细胞、CD57+细胞、CD20+细胞与组织学分级均无明显关系.(3)HCC中CD57+细胞和CD20+细胞随着临床分期的发展有下降的趋势(P ＜0.05);HCC中CD3+细胞平均数与临床TNM分期无关.(4)HCC中15月内有转移组的CD57+、CD3+细胞数均少于无转移组(P＜0.01).HCC患者15月内有无转移与HCC和癌旁组织中的B细胞分布均无关.结论临床上,随着HCC患者的病情恶化,CD3+、CD57+、CD20+细胞逐渐减少.CD3+、CD57+、CD20+细胞可成为反映机体抗肿瘤特异性细胞免疫状态和生物学行为及判断患者预后的重要指标.     

CD4+CD25+ cells regulate CD8 cell anergy in neonatal tolerant mice

BACKGROUND: Injection of neonatal BALB/c mice with semi-allogeneic splenocytes leads to antigen-specific tolerance lasting into adulthood. Tolerant mice accept A/J skin grafts and fail to generate CD8 cytotoxic T lymphocyte (CTL) activity against A/J targets. Anergic CD8 T cells are present in tolerant mice, and CD4 regulatory cells function to maintain CD8 cell anergy. METHODS: Neonatal BALB/c mice were injected with 108 live CAF, splenocytes, and mice were deemed tolerant by accepting A/J grafts over 40 days. CD8 cell proliferation was measured by in vitro incorporation of bromodeoxyuridine coupled with fluorescence-activated cell sorter analysis. Alloantigen-specific cytotoxicity was tested using 51Cr release assays of A/J or third-party targets. RESULTS: We demonstrate that A/J-specific anergic CD8 cells are present in neonatal primed mice that develop tolerance but not in neonatal primed mice that reject A/J skin grafts. Anergic CD8 cells show decreased proliferation and no CTL activity against A/J targets. Addition of interleukin-2 (IL-2) to unfractionated cultures fails to restore CTL activity against A/J targets. However, addition of IL-2 to CD4-depleted cultures restores A/J-specific CD8 CTL activity. Removal of CD4+/CD25+ cells, but not CD4+/CD25- cells, also restores CD8 CTL activity against A/J in the presence, but not the absence, of IL-2. Moreover, when added back into cultures, purified CD4+/CD25+ cells from tolerant mice inhibit the generation of CD8 CTL against A/J targets. CONCLUSION: These data indicate that CD8 anergy is associated with the state of tolerance, and that CD4+CD25+ cells from tolerant mice function to maintain A/J-specific CD8 cell anergy in vitro.     

CD4+CD25+ T-Cells Control Autoimmunity in the Absence of B-Cells

OBJECTIVE

Tumor necrosis factor ligand family members B-cell–activating factor (BAFF) and a proliferation-inducing ligand (APRIL) can exert powerful effects on B-cell activation and development, type 1 T-helper cell (Th1) immune responses, and autoimmunity. We examined the effect of blocking BAFF and APRIL on the development of autoimmune diabetes.

RESEARCH DESIGN AND METHODS

Female NOD mice were administered B-cell maturation antigen (BCMA)-Fc from 9 to 15 weeks of age. Diabetes incidence, islet pathology, and T- and B-cell populations were examined.

RESULTS

BCMA-Fc treatment reduced the severity of insulitis and prevented diabetes development in NOD mice. BCMA-Fc–treated mice showed reduced follicular, marginal-zone, and T2MZ B-cells. B-cell reduction was accompanied by decreased frequencies of pathogenic CD4⁺CD40⁺ T-cells and reduced Th1 cytokines IL-7, IL-15, and IL-17. Thus, T-cell activation was blunted with reduced B-cells. However, BCMA-Fc–treated mice still harbored detectable diabetogenic T-cells, suggesting that regulatory mechanisms contributed to diabetes prevention. Indeed, BCMA-Fc–treated mice accumulated increased CD4⁺CD25⁺ regulatory T-cells (Tregs) with age. CD4⁺CD25⁺ cells were essential for maintaining euglycemia because their depletion abrogated BCMA-Fc–mediated protection. BCMA-Fc did not directly affect Treg homeostasis given that CD4⁺CD25⁺Foxp3⁺ T-cells did not express TACI or BR3 receptors and that CD4⁺CD25⁺Foxp3⁺ T-cell frequencies were equivalent in wild-type, BAFF^−/−, TACI^−/−, BCMA^−/−, and BR3^−/− mice. Rather, B-cell depletion resulted in CD4⁺CD25⁺ T-cell–mediated protection from diabetes because anti-CD25 monoclonal antibody treatment precipitated diabetes in both diabetes-resistant NOD.μMT^−/− and BCMA-Fc–treated mice.

CONCLUSIONS

BAFF/APRIL blockade prevents diabetes. BCMA-Fc reduces B-cells, subsequently blunting autoimmune activity and allowing endogenous regulatory mechanisms to preserve a prehyperglycemic state.The members of the tumor necrosis factor (TNF) ligand family of molecules B-cell–activating factor (BAFF) (also known as BLyS, TNFSF13b) and a proliferation-inducing ligand (APRIL) can exert powerful effects on B-cell development, survival, and function; T-cell activation; and type 1 T-helper cell (Th1) immune responses and autoimmunity (1). BAFF exists as both a soluble and a membrane bound molecule and is expressed by a wide range of inflammatory-activated cells, including monocytes, macrophages, dendritic cells, and T-cells (2). In contrast, APRIL is processed intracellularly and exerts its function as a soluble protein. BAFF and APRIL can bind to one of two receptors: B-cell maturation antigen (BCMA) (3) or transmembrane activator and calcium modulator and cyclophylin ligand interactor (TACI) (3,4), whereas BAFF can also bind to BR3 (otherwise known as BAFF-R) (5). These receptors are found on a wide range of B-cell subsets including immature, transitional, mature, memory, and germinal center B-cells, as well as on plasma cells (2). Further, activated T-cells can express the receptors BR3 and TACI (4,6).BAFF has emerged as an important player in the development of autoimmunity. Elevated BAFF and APRIL levels have been detected in sera from human patients with rheumatoid arthritis, lupus, and Sjogren''s syndrome (7–9). Moreover, BAFF-transgenic mice harbor increased titers of self-reactive antibodies and develop autoimmune symptoms very similar to those of lupus and Sjogren''s syndrome (10,11). Forced expression of BAFF also results in a marked expansion of marginal-zone B-cells (MZBs) (12)—a B-cell subset associated with autoimmune conditions including lupus (13), Sjogren''s syndrome (11), and, more recently, type 1 diabetes (14,15). Thus, the BAFF/APRIL system can be considered a proinflammatory pathway associated with the development of autoimmunity (7,8). Indeed, studies designed to explore the therapeutic potential of BAFF pathway blockers for the treatment of autoimmune conditions are underway (16,17). This background makes targeting the BAFF/APRIL system a potential therapeutic candidate for the treatment of type 1 diabetes. This study was undertaken to test the hypothesis that targeting the BAFF/APRIL system would have multiple inhibitory effects on the spontaneous development of autoimmune diabetes in the NOD model.     

CD4+CD25+调节性T细胞在肿瘤免疫中的作用研究

CD4+CD25+调节性T细胞(Treg)在自身免疫耐受、免疫自稳、肿瘤免疫中发挥着重要作用,它可以抑制自身抗原或者非自身抗原如肿瘤抗原引起的免疫反应.人们对Treg细胞的免疫抑制作用已进行了相关的研究和临床应用,最新研究表明其能够诱导肿瘤特异性抗原和局部的免疫反应.此综述将讨论Treg细胞的相关表面分子及其在肿瘤免疫...     

Evaluation of lymphocytes CD4+ and CD8+ and expression of ZAP-70 kinase on CD3+ and CD19+ lymphocytes in obese patients undergoing laparoscopic cholecystectomy

Background

Obesity has become a global epidemic and a leading metabolic disease in the world. Laparoscopic surgeries may influence the function of the immunologic system. The percentages of CD4+ and CD8+ T lymphocyte cells have been described as prognostic factors for patients undergoing abdominal surgeries. This study aimed to evaluate the changes in CD4+ and CD8+ T lymphocyte cells, the ratio of CD4+ to CD8+ cells, and the ZAP-70 kinase expression on T CD3+ and B CD19+ cells in obese and normal-weight individuals undergoing laparoscopic cholecystectomy (LC).

Methods

The study group consisted of 46 asymptomatic patients with gallstones shown by ultrasound examination but without signs of any gallbladder complications. The patients underwent planned LC. Blood samples were obtained at three times, and the percentages of studied cells were measured by flow cytometry. Patients were enrolled to two groups: N group (body mass index [BMI], ≤25 kg/m²) and O group (BMI, ≥30 kg/m²). For statistical analysis, the Mann–Whitney U test and the Wilcoxon matched-pairs signed-ranks test were used. All p values lower than 0.05 were considered significant.

Results

The percentage of CD4+ T cells did not differ between the N and O groups before or after the surgery. Only in the N group did the percentage of CD4+ lymphocytes increase from 0 to 48 h. A higher percentage of CD8+ lymphocytes was observed in the O group postoperatively than in the N group. Differences of ZAP-70 kinase expression in the O group were observed at 24 and 48 h of the study. Decreased expression of ZAP-70 kinase was shown in the N group at both 0–24 and 24–48 h. In the O group, this tendency was noted at 24–48 h.

Conclusions

Immunologic activation after LC was confirmed in both weight groups. However, higher modulation, more typical for open surgeries, was observed in the obese group.