CSF enrichment of highly differentiated CD8+ T cells in early multiple sclerosis

CD8+ T cells may play an important role in multiple sclerosis (MS). Whether these cells would be involved in early stages of MS is unclear. We enrolled 52 patients with suspected MS, determined the recruitment of their highly differentiated (CCR7-/CD45RA+ or -) T cells (T(HD)) in the CSF as compared to peripheral blood and followed them for 12+/-7.3 months. A ROC curve showed that a CD8+/CD4+ T(HD) cells ratio of 0.94 helped to distinguish relapsing-remitting (RR-MS) and possible MS (Po-MS) from primary-progressive MS (PP-MS) and other neurological diseases patients (OND) patients (p=0.039), risk ratio of 2.29 (95% CI: 1.13-4.66; p=0.006). The CSF enrichment in CD8+ T(HD) cells was greater than in CD4+ T(HD) cells in RR/Po-MS patients (p=0.024) and than in CD8+ T(HD) cells in PP-MS/OND patients (p=0.006). These data suggest that CD8+ T(HD) cells play a role in the early stages of RR-MS.     

重症肌无力患者外周血中CD4~+CD25~+调节性T细胞的变化及意义

研究CD4 + CD2 5 + 调节性T细胞在重症肌无力 (MG )发病中的作用。本文采用三色流式细胞术对 2 9例MG患者和 2 3例健康对照者外周血中CD4 + CD2 5 + T细胞 (CD3+ CD4 + CD2 5 + )的百分率进行测定。结果显示病情未能很好控制的MG患者外周血CD4 + CD2 5 + T细胞比率略低于健康对照组 (分别为 3 79%± 1 4 0 %、 4 5 3%± 0 96 % ,P =0 12 ) ,病情稳定或缓解的MG患者CD4 + CD2 5 + T细胞比率 (8 4 5 %± 1 96 % )显著高于健康对照组 (P =0 0 0 0 1) ;胸腺切除的MG患者CD4 + CD2 5 + T细胞比率 (8 4 4 %± 2 39% )显著高于非胸腺切除的MG患者 (5 88%± 2 89% ,P =0 0 38)和健康对照组 (4 5 3%± 0 96 % ,P =0 0 0 3)。提示MG患者外周血中存在异常比例的CD4 + CD2 5 + 调节性T细胞 ,可能参与疾病的发生与发展。     

Increase of circulating CD4+CD25+ T cells in myasthenia gravis patients with stability and thymectomy

BACKGROUND: CD4(+)CD25(+) regulatory T cells are key controllers of peripheral immunological self-tolerance and suppress various autoimmune diseases in animal models, but few studies have been done to define their roles in myasthenia gravis (MG) so far. OBJECTIVE: To investigate frequencies and dynamic changes of blood CD4(+)CD25(+) T cells from MG patients. METHODS: The peripheral blood CD4(+)CD25(+) T cells of 29 MG patients and 23 healthy controls were detected by three-color flow cytometry. RESULTS: Myasthenic patients with symptomatically uncontrollable disease showed slightly lower percentages of CD4(+)CD25(+) T cells (mean = 3.79 +/- 1.40%; P = 0.12), whereas MG patients with clinically stable disease had significantly increased CD4(+)CD25(+) T cells (mean = 8.45 +/- 1.96%, P = 0.0001), as compared with healthy controls (mean = 4.53 +/- 0.96%). In addition, thymectomized MG patients had significantly higher percentages of CD4(+)CD25(+) T cells (mean = 8.44 +/- 2.39%), as compared with both non-thymectomized MG patients (mean = 5.88 +/- 2.89%, P = 0.038) and healthy controls (P = 0.003). CONCLUSIONS: Our observations indicate that increased percentages of CD4(+)CD25(+) T cells in MG patients may be related to disease stability and that thymectomy in patients with MG resulted in augmented CD4(+)CD25(+) T cells.     

CD4+, CD8+, and CD4− CD8− T Cells in CSF and Blood of Patients with Multiple Sclerosis and Tension Headache

Two-colour flow cytometric analysis was performed on paired samples of peripheral blood (PB) and cerebrospinal fluid (CSF) of patients with untreated multiple sclerosis (MS) and, for reference, subjects with muscular tension headache (TH) using anti-CD3, anti-CD4, anti-CD8, and anti-HLA-DR monoclonal antibodies in different combinations. CD4+/CD8+ T-cell ratio was increased in CSF compared to PB in both MS patients and TH subjects to a similar extent. This was mainly due to higher CD4+ T-cell levels in the CSF compartment. The proportion of HLA-DR+ T cells was higher in CSF than PB in both MS and TH; this increase of DR+ T cells in CSF was more prominent in MS. The level of CD4+ CD8+ T cells, which represent a subset of activated T cells, was not different between CSF and PB, either in MS or in TH. The proportion of CD4- CD8- T cells, which were found generally not to be blast cells, was lower in CSF compared to PB in both patient groups. However, their CSF level was higher and their PB level lower in MS compared to TH. Results point to an accumulation of activated T-helper cells in the CSF of both MS patients and healthy subjects. Fetal-type CD4- CD8- T cells bearing the unusual T-cell receptor gamma/delta seem to be selectively recruited to the CSF of MS patients.     

Decreased CD4+CD25+ T cells in peripheral blood of patients with systemic lupus erythematosus

Recent animal studies have shown that CD4+CD25+ T cells play a crucial role in the suppression of the immune response and that depletion of this subset of T cells might lead to development of autoimmune diseases. The aim of the present study was to investigate the levels of CD4+CD25+ T cells in the peripheral blood of patients with systemic lupus erythematosus (SLE). Ninety-four SLE patients, 52 patients with rheumatoid arthritis (RA) and 50 age- and gender-matched healthy individuals were enrolled in the study. A flowcytometric method was applied in the measurement of CD4+CD25+ T cells. The results showed that patients with SLE had statistically lower levels of CD4+CD25+ T cells than did normal controls, when expressed as either percentages of peripheral blood mononuclear cells (PBMCs) (mean +/- SD, 8.49 +/- 6.36 versus 11.11 +/- 4.58%, P < 0.05) or absolute cell numbers (98.77 +/- 97.52 versus 213.93 +/- 104.52 cells/mm3, P < 0.05). In terms of CD25brightCD4+ T cells, defined as having a fluorescence intensity of CD25 expression exceeding 100, SLE patients still had significantly lower levels than did normal controls expressed as percentages of PBMCs (1.76 +/- 1.32 versus 3.73 +/- 1.30%, P < 0.05). No significant differences could be found between RA patients and normal controls. The overwhelming majority of CD4+CD25+ T cells belonged to CD45RO+ cells and most did not express the CD69 molecule. Although decreased CD4+CD25+ T cells were found in SLE patients, we failed to find a significant correlation between the levels of CD4+CD25+ T cells and disease activities of SLE. To the best of our knowledge, this is the first study to demonstrate that patients with SLE had decreased CD4+CD25+ T cells. However, the exact role of the decreased CD4+CD25+ T cells in the pathogenesis of SLE remains to be elucidated.     

The presence of cytokine-suppressive CD4+CD25+ T cells in the peripheral blood and synovial fluid of patients with rheumatoid arthritis

CD4+CD25+ T cells have been shown to play a regulatory or suppressive role in the immune response and are possibly relevant to the pathogenesis of autoimmune diseases. In the present study, we attempted to investigate the levels of CD4+CD25+ T cells in the peripheral blood (PB) and synovial fluid (SF) of patients with rheumatoid arthritis (RA) and the effects of CD4+CD25+ T cells on the in vitro cytokine production by stimulated SF mononuclear cells (SFMC). The results showed that RA patients had similar frequencies of CD4+CD25+ T cells in PB, expressed as a percentages of the lymphocyte population, as did healthy subjects (mean +/- SD: 10.52 +/- 5.87% versus 11.11 +/- 4.58%., respectively). But in contrast to PB, the SF of RA patients contained significantly higher levels of CD4+CD25+ T cells (17.77 +/- 7.92% versus 10.52 +/- 5.87%, respectively. P < 0.001). When cocultured in vitro with SFMC, CD4+CD25+ T cells purified from either PB or SF were found to exert a considerable suppressive effect on the production of cytokines including TNF-alpha, IFN-gamma and interleukin-10 (IL-10). The percentages of inhibition of each cytokines ranged from 41.8 to 98.4% (mean, 80.0%) for TNF-alpha, 42.8 to 98.9% (mean, 83.2%) for IFN-gamma and 59.3 to 96.6% (mean, 80.0%) for IL-10. Because both pro-inflammatory and anti-inflammatory cytokines were suppressed by CD4+CD25+ T cells, whether CD4+CD25+ T cells might play a beneficial role in the suppression of sustained inflammation in rheumatoid synovium remains to be elucidated.     

CD4+ CD25+调节性T细胞在HIV/AIDS患者中的作用及其与HIV病毒载量的相关性研究

目的 研究HIV感染者／AIDS患者外周血CD4^＋ CD25^＋ 调节性T细胞（CD4^＋ CD25^＋ regulatory Tcell，Treg）频率、功能及其临床意义。方法 选择31例HIV感染者／AIDS患者和30例健康对照者，采用流式细胞仪检测各组外周血Treg的表型和频率。采取MACS磁珠分选CD4^＋CD25^＋T细胞，利用[^3H]胸腺嘧啶掺入法检测CD4^＋ CD25^＋T细胞在特异性HIV抗原刺激下对CD4^＋ CD25-T细胞的增殖影响。结果HIV／AIDS患者组与正常对照组相比较，外周血CD4^＋ CD25^＋ T细胞频率在统计学上差异无统计学意义。与正常对照组比较，HIV感染者外周血CD4^＋ CD25^＋ T细胞频率升高，差异有统计学意义（P〈0.01）；与正常对照组比较，AIDS患者者外周血CD4^＋ CD25^＋ T细胞频率降低，差异有统计学意义（P〈0．0001）。HIV RNA病毒载量与患者外周血CD4^＋ CD25^＋ T细胞数量呈正相关性（P〈0．01）。CD4^＋ CD25^＋ T细胞具有抑制HIV特异性的CD4^＋ CD25^- T细胞的增殖作用。结论HIV感染者／AIDS患者的细胞免疫功能紊乱，CD4^＋ CD25^＋ T细胞能抑制HIV感染者／AIDS患者的HIV特异性细胞免疫反应，促进HIV病毒复制，与形成持续HIV感染有关。     

Circulating CD3+ CD4+ CD+ T lymphocytes in multiple sclerosis

Triple-antibody flow cytometry was used to search for distinctive populations of peripheral blood lymphocyte immunophenotypes in multiple sclerosis (MS). Using monoclonal antibodies to the cell surface markers CD3, CD4, and CD8, T cell subsets were quantified on a cohort of 31 MS patients (not treated with corticosteroids for at least 6 months), 30 healthy donors, and 14 patients with other autoimmune diseases (also corticosteroid treatment-free for at least 6 months). Untreated MS patients displayed a significantly greater population of CD3+CD4+CD8+ circulating T cells than healthy donors (P = 0.023). Patients with other autoimmune diseases displayed mean populations of CD3+CD4+CD8+ cells greater than normal donors and less than MS, but not significantly different from either. An additional 45 MS patients who had received corticosteroid therapy within the previous 6 months were phenotyped. Treatment of symptomatic MS with corticosteroids was associated with a smaller population of circulating CD3+CD4+CD8+ cells. Some MS patients have significantly greater numbers of peripheral blood T lymphocytes simultaneously expressing CD3, CD4, and CD8 surface markers than healthy donors and this population of cells may be reduced by corticosteroids treatment. This triple positive phenotype may be a manifestation of a systemic immune abnormality in MS.     

Compromised CD4+ CD25(high) regulatory T-cell function in patients with relapsing-remitting multiple sclerosis is correlated with a reduced frequency of FOXP3-positive cells and reduced FOXP3 expression at the single-cell level

CD4+ CD25(high) regulatory T cells (Tregs) of patients with relapsing-remitting (RR) multiple sclerosis (MS), in contrast to those of patients with secondary progressive (SP) MS, show a reduced suppressive function. In this study, we analysed forkhead box P3 (FOXP3) at the single-cell level in MS patients and controls (healthy individuals and patients with other neurological diseases) by means of intracellular flow cytometry. Our data revealed a reduced number of peripheral blood CD4+ CD25(high) FOXP3+ T cells and lower FOXP3 protein expression per cell in RR-MS patients than in SP-MS patients and control individuals, which was correlated with the suppressive capacity of Tregs in these patients. Interestingly, interferon (IFN)-beta-treated RR-MS patients showed restored numbers of FOXP3+ Tregs. Furthermore, a higher percentage of CD4+ CD25(high) FOXP3+ Tregs in RR-MS patients, as compared with controls and SP-MS patients, expressed CD103 and CD49d, adhesion molecules involved in T-cell recruitment towards inflamed tissues. This was consistent with a significantly increased number of CD27+ CD25(high) CD4+ T cells in the cerebrospinal fluid (CSF), as compared with peripheral blood, in RR-MS patients. Taken together, these data show aberrant FOXP3 expression at the single-cell level correlated with Treg dysfunction in RR-MS patients. Our results also suggest that Tregs accumulate in the CSF of RR-MS patients, in an attempt to down-regulate local inflammation in the central nervous system.     

慢性HBV感染者外周血CD4+CD25high调节性T细胞初步分析

目的 分析不同临床乙型肝炎病毒(HBV)慢性感染者外周血中CD4+CD25high调节性T细胞(Treg)的水平及其与各种临床指标的关系.方法 采集35例不同临床表现成年慢性HBV感染者(HBsAb+组5例、非活动肝炎组8例、活动肝炎组12例、免疫耐受期组10例)及12例健康成人外周血标本,流式细胞仪分析外周血中CD4+CD25high Treg含量,ELISA法检测HBsAg、HBsAb、HBeAg、HBeAb、HBcAb,RT-PCR法检测HBV DNA载量,同时进行肝脏生化功能检测,并进行统计学分析.结果 HBV慢性感染者[(12.35±6.48)个/μl;(1.82 4-0.87)%)]及健康成人外周血标本[(8.91±3.11)个/μl,(1.35±0.39)%]中CD4+CD25highTreg绝对计数和其占CD4+T细胞百分含量差异均无统计学意义(P＞0.05);分组分析发现,免疫耐受期组CD4+CD25highTreg占CD4T细胞百分含量高于HBsAb+组、活动肝炎组及健康对照组(P＜0.05);免疫耐受期组CD4+CD25highTreg绝对计数高于健康对照组(P＜0.05);余各组间差异无统计学意义(P＞0.05).分析CD4+CD25highTreg含量与临床指标间相关性发现,CD4+CD25highTreg占CD4+T细胞百分含量与丙氨酸氨基转移酶(ALT)水平呈负相关(r=-0.418,P=0.038),与CD4/CD8比值呈正相关(r=0.344,P=0.021),与HBV DNA水平无相关性(r=0.118,P＞0.05);CD4+CD25highTreg绝对计数与CD4/CD8比值呈正相关(r=0.360,P=0.015),与ALT水平及HBV DNA水平无相关性(r=-0.211,r=-0.060,P＞0.05).结论 CD4+CD25highTreg在HBV慢性感染的免疫发病机制中可能发挥一定作用.     

CD4+-T-cell counts, spontaneous apoptosis, and Fas expression in peripheral blood mononuclear cells obtained from human immunodeficiency virus type 1-infected subjects.

We examined the relationships among CD4+-T-cell counts, spontaneous apoptosis, and Fas expression among peripheral blood mononuclear cells obtained from human immunodeficiency virus type 1 (HIV-1)-infected patients. After 2 days of incubation, propidium iodide DNA staining and flow cytometry revealed that peripheral blood mononuclear cells from subjects with the lowest CD4+-cell numbers (0 to 99/microl; n = 20) showed the highest frequency of apoptosis: 22.4% +/- 2.7% (mean +/- standard error) versus 13.8% +/- 1.2% and 12.7% +/- 1.4% among peripheral blood mononuclear cells obtained from patients with 100 to 499 CD4+ cells/microl (n = 19) and >500 CD4+ cells/microl (n = 17), respectively. Each of these means differed significantly from the mean frequency of apoptosis (6.3% +/- 0.7%) of peripheral blood mononuclear cells obtained from HIV-1-seronegative controls (P < 0.001, Student's t test). After incubation, the percentage of peripheral blood mononuclear cells expressing Fas antigen was increased for the HIV-1-infected subjects, and this was most evident for patients with more advanced disease. Among patients with fewer than 100 CD4+ cells/microl, 64.4% +/- 5.4% of peripheral blood mononuclear cells were Fas+, as opposed to 25.8% +/- 3.0% and 14.5% +/- 1.7% Fas+ cells among patients with more than 100 CD4+ cells/microl and healthy controls, respectively (P < 0.05 for each group comparison). Interestingly, in all populations, most apoptotic cells did not express Fas. Thus, apoptosis and Fas expression are increased in incubated peripheral blood mononuclear cells obtained from HIV-1-infected patients and these phenomena are enhanced as disease progresses.     

乙型肝炎病毒感染者外周血CD4＋T细胞CD25-CD127-表达的检测及临床意义

目的 检测乙型肝炎病毒（ HBV）感染者外周血CD4＋T细胞表面CD25 - CD127 -的表达情况及临床意义.方法 用流式细胞术比较分析53例慢性乙肝患者、53例HBV携带者和26例正常对照人群CD4＋T细胞表面CD25 - CD127 -的表达情况,并对20例用干扰素治疗的HBV-DNA阳性慢性乙肝患者随访.结果 ①与正常对照组比较,慢性乙肝患者、HBV携带者CD4＋ CD25 -CD127 -T细胞均显著升高,两者比较有统计学差异（Q =4.559,P＜0.05;Q=6.230,P＜0.05）;②HBV- DNA阳性患者（n=77） CD4＋ CD25 - CD127 -T细胞显著低于HBV- DNA阴性患者（n=29）,两者比较有统计学意义（t =2.290,P=0.024）;③与治疗前比,慢性乙肝患者干扰素治疗12周后CD4＋CD25- CD127 -T细胞显著降低,两者比较差异有统计学意义（t =2.469,P=0.024）.结论 乙型肝炎病毒感染者外周血CD4＋ CD25 - CD127 -T细胞与病毒的感染和清除相关,外源性干扰素可降低CD4＋ CD25 - CD127 -T细胞.     

The severity of systemic lupus erythematosus negatively correlates with the increasing number of CD4+CD25(high)FoxP3+ regulatory T cells during repeated plasmapheresis treatments of patients

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by increased pathologic autoantibody production. A decrease in the number of CD4+CD25(high)FoxP3+ regulatory T cells can play a key role in the loss of tolerance to self antigens. Our aim was to determine the absolute number of peripheral CD4+CD25(high)FoxP3+ T cells in 44 patients with SLE, furthermore, to measure the changes in the number of CD+CD25(high)FoxP3+ T cells in 5 patients with severe SLE treated with repeated plasmapheresis for 4-6 days in comparison to the changes in the activity of disease (SLEDAI). Percent of CD4+CD25(high)FoxP3+ T cells were measured by flow cytometry. The absolute number of peripheral CD4+CD25(high)FoxP3+ T cells was significantly decreased in the 44 patients with SLE compared to the healthy controls n = 32 (0.012 +/- 0.006 vs. 0.038 +/- 0.017 G/L, p < 0.05). In the 5 patients with severe SLE the repeated plasmapheresis treatments increased the peripheral number of CD4+CD25(high)FoxP3+ T cells. As the number of CD4+CD25(high)FoxP3+ T cells increased during the treatment, the activity of disease (the value of SLE activity index) decreased. In the peripheral blood of SLE patients not only the ratio was decreased (as it was published earlier) but also the absolute number of these regulatory T cells. The repeated plasmapheresis treatments of SLE patients induced a significant increase in the number of peripheral CD4+CD25(high)FoxP3+ T cells in parallel to the decrease in the values of SLEDAI (the activity of disease). This phenomenon is, among others, possibly due to the elimination of interpheron-alpha and lymphocytotoxic antibodies during plasmapheresis.     

CD4+CD25high调节性T细胞在类风湿性关节炎病程中的消长及其意义

目的研究类风湿性关节炎(RA)患者病情发展不同阶段外周血及滑液中CD4 CD25high调节性T细胞数量的差别,及其与类风湿性关节炎活动程度的相关性,探讨CD4 CD25highT细胞在RA发生发展中所发挥的免疫抑制和调节作用。方法分别选取未经过缓解病情抗风湿药(DMARDs)治疗的活动性RA患者11例,经DMARDs治疗病情缓解的RA患者12例,和DMARDs治疗后效果不佳的RA患者9例,以及正常对照8例,检测他们的外周血淋巴细胞,以流式细胞术检测CD4 CD25high调节性T细胞的百分率,并研究CD4 CD25highT细胞百分率与抗环瓜氨酸(CCP)抗体,C反应蛋白(CRP),血沉(ESR)及类风湿因子(RF)的相关性。对其中部分患者的血液和关节滑液同时进行分析。结果RA未经治疗组和治疗效果不佳组CD4 CD25highT细胞的百分率(分别是5.24%和6.43%)明显低于正常对照组和治疗后病情缓解组(分别是17.17%和11.79%,P<0.01)。RA患者CD4 CD25highT细胞的百分率与抗CCP抗体(58.0Ru/mL),ESR(38.8mm/h)及CRP(2.73μg/L)呈明显负相关(P<0.05),与类风湿因子(RF=14.4Iu/mL)无明显的相关性(P=0.054)。正常对照组的CD4 CD25highT细胞百分率与抗CCP抗体(均<5.0Ru/mL),ESR(4.67mm/h),CRP(0.15μg/L)及RF(1.37)无明显相关性(P>0.1)。RA患者关节滑液中CD4 CD25highT百分率明显低于强直性脊柱炎(ankilosing spondylitis,AS)关节积液患者(P<0.05)。结论试验结果表明未经缓解病情治疗和治疗后效果不佳者的外周血中,CD4 CD25high调节性T细胞相对减少,且与病情活动程度负相关,这可能是RA发生和发展的一个重要因素。     

CD4+CD25+调节性T细胞与系统性红斑狼疮病情活动性关系的研究

目的：检测系统性红斑狼疮患者外周血CD4^＋CD25^＋、CD4^＋CD8^＋调节性T细胞亚群，探讨其与疾病活动性、肾脏损伤、血清抗ds-DNA抗体及免疫球蛋白和补体C3含量的关系。方法：采用流式细胞术检测北京协和医院住院和门诊SLE患者（n=37）外周血CD4^＋CD25^＋T、CD4^＋CD8^＋T细胞群比例，以15例RA和15例SS组成自身免疫性疾病对照，30例健康体检者作为正常对照，观察调节性T细胞亚群与SLE患者疾病活动性指标SLEDAI、IgG、C3及血清抗ds-DNA抗体的关系。结果：①疾病活动期SLE患者外周血CD4^＋CD25^＋调节性T细胞群比例显著低于正常对照组（P〈0.01），疾病稳定期和风湿性疾病对照组与正常对照组结果差异无统计学意义。疾病活动期和稳定期SLE患者CD4＋CD8＋T细胞群比例都略高于正常对照组，但未发现结果差异有统计学意义（P〉0.05）。②疾病活动期SLE患者外周血CD4^＋CD25^＋T细胞比例及CD4^＋CD25^＋/CD4^＋值显著低于稳定期患者（P〈0.01）。SLE患者外周血CD4^＋CD25^＋/CD4^＋值与SLEDAI、补体C3呈低度相关（r分别为-0.491、0.368，P〈0.05），CD4^＋CD25^＋T细胞数量与SLEDAI呈负相关（r=-0.578，P〈0.05）。③SLE并发肾病组外周血CD4^＋CD25^＋T细胞群比例及CD4^＋CD25^＋/CD4^＋值显著低于非肾病组（P〈0.01；P〈0.05）。同一SLE患者治疗前后CD3^＋CD4^-CD8^-细胞和NK细胞降低，CD4^＋CD25^＋细胞、CD4^＋CD25^＋/CD4^＋值及CD8^＋T细胞增加，但未发现这些结果差异有统计学意义。本次研究未发现NK细胞、CD4^＋CD8＋T细胞、CD4^＋CD25^＋T细胞群比例在ds-DNA＋组与ds-DNA-组之间结果差异有统计学意义。结论：SLE患者外周血CD4^＋CD25^＋T细胞群比例与SLEDAI成负相关，与肾脏的损害也有密切关系，但与血清抗ds-DNA抗体产生的关系不明显。活动期SLE患者外周血CD4^＋CD25^＋T细胞减少，稳定期CD4^＋CD25^＋T细胞比例回升，因此推测CD4^＋CD25^＋T细胞的变化可能是导致疾病发生和病情发展及相关器官（如肾脏）损伤的关键环节之一。     

Transfer of cell membrane components via trogocytosis occurs in CD4+ Foxp3+ CD25+ regulatory T-cell contact-dependent suppression

A key component of the immune system is its ability to establish and maintain peripheral tolerance. Naturally occurring CD4+ CD25+ Foxp3+ regulatory T (nTreg) cells represent an important means by which this is accomplished, through their potent ability to suppress the actions of both CD4+ and CD8+ effector (Teff) cells in vitro and in vivo. We hypothesized that direct contact between nTreg and Teff cells is sufficient for nTreg cell-contact suppression. We first show that nTreg cell suppression is independent of APCs and their derived co-stimulatory signals. We then used a two-colour, lipid dye labelling and quantification approach to formally demonstrate that nTreg cells specifically form cell conjugates with responding T (Tresp) cells only under TCR activating conditions. Strikingly, activated CD4+ nTreg cells undergo progressive trogocytosis, a process by which membrane fragments are transferred from one cell subset to another, with Tresp cells more readily than Teff cells. These results are the first to show that nTreg cell cognate interactions with Tresp cells leads to trogocytosis between the cells, and the first to relate the degree of trogocytosis with the level of nTreg-mediated suppression.     

Alterations of peripheral CD4+CD25+Foxp3+ T regulatory cells in mice with STZ-induced diabetes

Complications arising from abnormal immune responses are the major causes of mortality and morbidity in diabetic patients. CD4+CD25+T regulatory cells (Tregs) play pivotal roles in controlling immune homeostasis, immunity and tolerance. The effect of hyperglycemia on CD4+CD25+Tregs has not yet been addressed. Here we used streptozotocin (STZ)-induced diabetic mice to study the effects of long-term hyperglycemia on CD4+CD25+Tregs in vivo. Four months after the onset of diabetes, the frequency of CD4+CD25+Foxp3+ T regulatory cells was significantly elevated in the spleen, peripheral blood lymphocytes (PBLs), peripheral lymph nodes (pLNs) and mesenteric LNs (mLNs). CD4+CD25+Tregs obtained from mice with diabetes displayed defective immunosuppressive functions and an activated/memory phenotype. Insulin administration rescued these changes in the CD4+CD25+ Tregs of diabetic mice. The percentage of thymic CD4+CD25+ naturally occurring Tregs (nTregs) and peripheral CD4+Helios+Foxp3+ nTregs were markedly enhanced in diabetic mice, indicating that thymic output contributed to the increased frequency of peripheral CD4+CD25+Tregs in diabetic mice. In an in vitro assay in which Tregs were induced from CD4+CD25- T cells by transforming growth factor (TGF)-β, high glucose enhanced the efficiency of CD4+CD25+Foxp3+ inducible Tregs (iTregs) induction. In addition, CD4+CD25- T cells from diabetic mice were more susceptible to CD4+CD25+Foxp3+ iTreg differentiation than those cells from control mice. These data, together with the enhanced frequency of CD4+Helios-Foxp3+ iTregs in the periphery of mice with diabetes, indicate that enhanced CD4+CD25+Foxp3+ iTreg induction also contributes to a peripheral increase iCD4+CD25+Tregs in diabetic mice. Our data show that hyperglycemia may alter the frequency of CD4+CD25+Foxp3+ Tregs in mice, which may result in late-state immune dysfunction in patients with diabetes.     

新生儿脐带血CD4+CD25high调节性T细胞Foxp3的表达

目的:检测新生儿脐带血CD4 CD25high调节性T细胞(Treg)数量及胞内转录因子Foxp3的表达,探讨Treg细胞在新生儿期的表达特点.方法:采集新生儿脐带血(n=15)和成人外周血(n=12),密度梯度离心法获取单个核细胞用荧光标记单克隆抗体(mAb)作表面和胞内染色后,在流式细胞仪上检测CD4 CD25highTreg细胞的数量及其胞内转录因子Foxp3的表达.结果:脐带血Treg细胞占CD3 CD4 T细胞的比例(3.86%±1.63%)明显高于成人外周血(0.87%±0.74%,P<0.01);而脐带血Treg细胞中表达Foxp3的比例明显低于外周血Treg细胞(23.21%±8.9%vs71.3%±11.6%,P<0.01).结论:虽然新生儿脐带血CD4 CD25highTreg细胞数量明显高于成人外周血,但Foxp3 细胞数量明显低于成年人,提示在功能上可能尚未成熟.     

CD4+CD25+FoxP3+调节T细胞抑制肺结核患者特异细胞免疫

  目的 了解结核患者外周血中CD4+CD25+FoxP3+调节T细胞在抑制结核患者结核特异细胞免疫反应中的作用。 方法 使用细胞分离、流式细胞分析、细胞增殖和细胞因子测定等方法,比较结核患者及健康正常人群外周血中CD4+CD25+FoxP3+调节T细胞的量及功能特征的差异。 结果 结核患者外周血中CD4+CD25+FoxP3+调节T细胞数占CD4+细胞总数的比例显著高于健康正常人群;在BCG及ESAT-6的刺激下,结核患者外周血单个核细胞增殖能力和产生γ-干扰素的能力比健康正常人群明显增强。在BCG刺激下,结核患者外周血CD4-细胞产生γ-干扰素(1289.62±519.01)及白介素-10(1045.40±534.12)的能力比结核患者外周血BPMCs细胞产生γ-干扰素(624.50±261.13)及白介素-10(377.00±249.56)的能力显著增强(均p<0.05);在BCG及ESAT-6的刺激下,结核患者外周血CD4+CD25+调节T细胞显著抑制结核患者外周血CD4+CD25-细胞产生γ-干扰素及白介素-10。 结论 结核患者CD4+CD25+FoxP3+调节T细胞数量增多,抑制结核患者结核特异细胞免疫反应功能增强,可能与结核的发生、发展及转归有密切关系。     

Alterations in levels of CD28-/CD8+ suppressor cell precursor and CD45RO+/CD4+ memory T lymphocytes in the peripheral blood of multiple sclerosis patients.

A comprehensive peripheral blood immunophenotype analysis of 16 multiple sclerosis (MS) patients was performed by three-color flow cytometric analysis, and the results were compared with those for age-matched healthy controls. The cell subsets quantified included T cells (CD3+), B cells (CD19+), NK cells (CD56+), CD4+ and CD8+ T cells, cytotoxic (CD28+) and suppressor precursor (CD28-) CD8+ T cells, CD45RA+ and CD45RO+ T cells (CD4+ and CD8+), and CD5+ T and B cells. Analysis of MS patients' peripheral blood revealed essentially normal levels of total T, B, and NK cells. In agreement with results obtained by other investigators, it was found that MS patients had an increased CD4/CD8 ratio, primarily due to a decrease in CD8+ T cells. MS patients were found to have a significantly decreased level of suppressor precursor (CD28-) CD8+ T cells compared with that of controls but to have normal levels of cytotoxic (CD28+) CD8+ T cells. These data indicate that MS patients do not have a general decrease in CD8+ T cells but that they have a specific decrease in the suppressor precursor subset only and normal levels of cytotoxic CD8+ T cells. MS patients also had a significant increase in memory (CD45RO+) CD4+ T cells and displayed a trend towards a decrease in naive (CD45RA+) T cells in the peripheral blood.