GD患者外周血CD4+CD28-T细胞亚群的表型特征及临床意义

检测Graves病(GD)患者外周血CD4~+CD28-T细胞水平及其表面CD45RO/CD45RA及ICOS的表达,探讨CD4~+ CD28-T细胞亚群在GD免疫致病机制中的作用。采用三色荧光抗体染色及流式细胞术检测了42例初发GD患者和30例健康者外周血中CD4~+CD28-T细胞的百分率及其表面CD45RO/CD45RA和ICOS表达水平,同时检测其甲状腺功能并进行相关性分析。结果GD患者外周血中CD4~+CD28-T细胞百分率明显高于健康对照组,并高表达ICOS分子,与FT3水平显著正相关;与健康对照组相比,GD患者CD4~+CD28~-CD45RO~+T细胞百分率也显著增高,而CD4~+CD28~-CD45RA~+T细胞呈下降趋势,FT3、FT4水平与CD4~+CD28-T细胞表面CD45RO的表达率呈正相关,而FT3水平与CD45RA表达呈负相关。结论GD患者外周血CD4~+CD28~-T细胞异常增高,表面高表达ICOS分子,具有记忆性细胞的表型特征,与甲状腺功能异常有一定的相关性,CD4~+CD28-T细胞可能是参与GD免疫病理反应的自身反应性T细胞。     

CHOP方案治疗前后外周T细胞淋巴瘤患者外周血CD45RA~+ T和CD45RO~+ T的变化特点

目的:探讨CHOP方案对外周T细胞淋巴瘤(PTCL)患者外周血中初始和记忆T细胞水平的变化及其临床意义。方法:采用流式细胞术检测20例PTCL患者CHOP方案化疗前后外周血中CD4+CD45RA+、CD4+CD45RO+、CD8+CD45RA+和CD8+CD45RO+T细胞的比例,分析疗效与T细胞亚群的关系。结果:PTCL患者化疗前外周血中CD4+T细胞、CD4+CD45RO+细胞的比例明显降低,CD4+CD45RA+、CD8+、CD8+CD45RO+和CD8+CD45RA+T细胞的比例均明显升高(P<0.05),而化疗后PTCL患者CD4+、CD4+CD45RO+细胞的比例较治疗前升高,CD4+CD45RA+、CD8+、CD8+CD45RO+和CD8+CD45RA+T细胞比例则较治疗前稍下降(P<0.05)。治疗前后化疗有效组的CD4+CD45RA+均明显高于化疗无效组(P<0.05)。结论:CHOP治疗对PTCL患者胸腺输出功能有一定的影响,伴有较高胸腺输出功能者对化疗效果更好。     

CD4~+CD25~+调节性T细胞在自身免疫性甲状腺疾病中数量和功能变化

目的:探讨自身免疫性甲状腺疾病患者外周血中CD4+CD25+调节性T细胞(Tregs)的数量和功能变化。方法:采用化学发光法测定20例初发Graves’病人、20例初发桥本甲状腺炎(HT)患者及20例健康体检者血清中促甲状腺素(TSH)、总三碘甲状腺原氨酸(TT3)、总甲状腺素(TT4)、甲状腺球蛋白抗体(TgAb)和甲状腺过氧化酶抗体(TPOAb)的水平;用流式细胞仪分析外周血单个核细胞(PBMC)中CD4+T细胞及CD4+CD25+Tregs的数量;采用磁珠分选技术分选5例HT病人和5例健康体检者PBMC中CD4+CD25+Tregs和CD4+CD25-T细胞,采用MTT法检测CD4+CD25+Tregs对自身CD4+CD25-T细胞增殖的抑制作用;提取各组PBMC的总RNA,经Real time-PCR检测TGFβ-1、Foxp3 mRNA的表达水平。结果:流式细胞检测结果显示,初发Graves’病人、初发HT患者外周血PBMC中CD4+T细胞数量与正常人比较无差异(P<0.05);初发HT患者外周血PBMC中CD4+CD25+Tregs占CD4+T细胞的比率为(1.55%±0.49%),明显低于正常对照组(2.86%±1.04%)(P<0.05);初发Graves’病人外周血PBMC中CD4+CD25+Tregs占CD4+T细胞的比率为(3.25%±0.97%),与正常对照组(2.86%±1.04%)相比无显著性差异(P<0.05)。MTT结果显示,初发HT患者CD4+CD25+Tregs对自身CD4+CD25-T细胞增殖的抑制百分率为15.7%±5.36%,与正常组(41.7%±9.87%)相比显著降低(P<0.05)。Real time-PCR结果显示,初发Graves’病人、初发HT患者PBMC的TGFβ-1 mRNA表达水平分别为(0.37±0.10)和(0.43±0.09),均明显低于正常对照组(1.02±0.04)(P<0.05);初发Graves’病人、初发HT患者PBMC的Foxp3 mRNA表达水平分别为0.62±0.09和0.42±0.29,均明显低于正常对照组(0.99±0.17)(P<0.05)。结论:本研究结果提示,HT患者外周血中CD4+CD25+Tregs的数量和功能明显降低。Graves’病和HT患者外周血PBMC中TGFβ-1、Foxp3 mRNA表达水平明显降低。     

结直肠癌患者与健康受试者外周血CD45RA+/CD45RO+淋巴细胞表型分析

目的 分析结直肠癌患者与健康受试者外周血CD45RA+/CD45RO+系列T淋巴细胞表达的差异.方法 运用流式细胞术(FCM)检测2010年1月至2013年12月解放军总医院收治的109例结直肠癌患者(试验组)与64例健康受试者(对照组)外周血CD45RA+、CD45RO+、CD4+ CD45RA+、CD4+ CD45RO+T淋巴细胞亚群表达情况,统计分析试验组和对照组性别和年龄的分布是否存在差异,然后进一步分析CD45 RA等T淋巴细胞亚群与结直肠癌临床分期的关系.结果Ⅰ+Ⅱ期、Ⅲ期和Ⅳ期结直肠癌患者外周血CD45 RA+细胞百分率[三者分别为(56.23±7.75)％、(58.86±7.66)％和(59.02±9.71)％]明显高于对照组[(48.94±12.66)％],差异具有统计学意义(F=11.128,P＜0.001);Ⅲ期和Ⅳ期患者的CD45RO+细胞百分率[分别为(47.19±8.30)％和(45.41±10.45)％]则明显低于对照组[(53.43±11.75)％],差异具有统计学意义(F=5.817,P=0.00083);Ⅲ期和Ⅳ期患者CD45RA+/CD45RO+的比值(分别为1.32 ±0.46和1.43±0.63)明显高于对照组(1.00±0.47),差异具有统计学意义(F=6.986,P=0.000185);Ⅰ+Ⅱ期患者CD4+ CD45 RO+细胞百分率[(31.37±6.39)％]明显高于对照组[(27.49±7.19)％],差异具有统计学意义(F=2.368,P=0.009);Ⅳ期患者CD4+ CD45RA+/CD4+ CD45RO+的比值(0.66±0.39)明显高于Ⅰ+Ⅱ期的患者(0.49±0.23),差异具有统计学意义(F=1.812,P=0.029);各组之间CD4+ CD45RA+细胞百分率无明显统计学差异(F=0.637,P=0.592).结论 随着临床分期的增加,结直肠癌患者外周血CD45RA+细胞逐渐增加而CD45RO+细胞逐渐减少,反映出结直肠癌患者随着肿瘤的进展其免疫功能逐渐抑制、逐渐降低的动态过程;CD4+ CD45RA+细胞和CD4+ CD45RO+细胞在反映结直肠癌患者机体免疫功能方面不如CD45RA+细胞和CD45RO+细胞敏感.     

急性冠脉综合征患者胸腺新近输出CD4~+CD25~+调节性T细胞的检测及意义

目的:探讨急性冠脉综合征患者胸腺新近输出的CD4+CD25+调节性T细胞(Treg)的水平及意义。方法:实验共分3组:急性冠脉综合征(ACS)组28例,稳定型心绞痛(SA)组25例和健康对照(HCs)组24例。采用CD31作为胸腺新近输出的典型标志,用磁性细胞分离器(MACS)分离各组CD4+CD25+调节性T细胞,流式细胞分析法检测各组患者外周血CD31+Treg占Treg细胞的比例,应用实时定量PCR检测CD4+CD25+调节性T细胞中T细胞受体重排删除环的数量。结果:ACS组外周血CD31+Treg/Treg比例明显低于SA组(P=0.003)和HCs组(P<0.001)。ACS组Treg细胞中TREC的数量亦明显低于SA组(P=0.001)和HCs组(P<0.001)。而SA组和HCs组间差异均无统计学意义(P=0.106和P=0.566)。患者CD31+Treg的比例与Treg细胞中TREC的数量呈正相关(r=0.493,P=0.014)。结论:急性冠状动脉综合征患者胸腺新近输出CD4+CD25+调节性T细胞减少可能是动脉粥样斑块不稳定的原因。     

2型糖尿病患者外周血CD8+CD25+Foxp3+Treg细胞检测及意义

目的探讨外周血CD8~+CD25~+Foxp3~+Treg(CD8~+Treg)细胞比例在2型糖尿病(T2DM)疾病过程中的作用。方法选取T2DM患者90例。根据尿微量白蛋白(MAL),分为45例T2DM伴正常蛋白尿患者(NMAU,MAL30 mg/24 h),45例T2DM伴微量蛋白尿患者(MAU,MAL 30～300 mg/24 h),同时选择门诊体检健康人员45名作为对照组(HC)。通过特定蛋白仪检测患者mAlb浓度;流式细胞仪检测CD8~+Treg细胞比例;Luminex200检测血浆白细胞介素(IL)-8、1β、6和肿瘤坏死因子(TNF)-α浓度。结果与HC组[4.43(3.26～5.75)%]相比,NMAU组[4.06(3.15～5.43)%]和MAU组[3.52(2.30～4.87)%]患者CD8~+Treg细胞比例降低,且MAU组降低更明显(P0.05);与HC组相比,MAU组和NMAU组患者血浆细胞因子TNF-α、IL-8、IL-6和IL-1β浓度均升高(P0.05);MAU组患者CD8~+Treg比例与血清细胞因子TNF-α(r=-0.444 8,P0.01)、IL-8(r=-0.341 2,P0.05)、IL-6(r=-0.365 3,P0.05)和IL-1β(r=-0.319 2,P0.05)呈负相关;Logistic回归分析显示CD8~+Treg对T2DM患者可能具有保护作用。结论通过调控T2DM患者外周血CD8~+Treg细胞比例,有可能减缓糖尿病的进程。     

不同原位肝移植模型大鼠的CD4~+CD25~+调节性T细胞数量变化的研究

目的建立稳定的大鼠原位肝移植模型,并检测大鼠外周血中CD4+CD25+调节性T细胞(regulatory T cells,Treg)比例的变化。方法采用近交系成年雄性BN、LEW大鼠,改良"二袖套"法建立肝移植模型31例。术前随机分为3组:排斥组(LEW→BN,n=9),耐受组(BN→LEW,n=11),同基因组(BN→BN,n=11)。存活的受体分别于术后5 d、10 d、30 d取外周血,分离外周血中的单个核细胞,由流式细胞仪检测CD4+CD25+Treg比例。并于相应时间点每组随机各处死2只,取肝脏标本观察病理学变化。每组选取5例来观察生存期,存活>100 d时各处死2只,取肝脏标本。结果中位生存期:排斥组14 d,耐受组112 d,同基因组129 d。耐受组与同基因组术后未见明显排斥反应。术后7 d,排斥组肝脏病理Banff评分Ⅲ级。肝移植早期,排斥组和自发耐受组的外周血中CD4+CD25+Treg比例均增加,术后10 d耐受组CD4+CD25+Treg比例明显高于同基因组(P<0.01)。术后30 d,耐受组CD4+CD25+Treg比例仍维持在较高水平。结论 BN与LEW大鼠组合可建立稳定可靠的急性排斥模型与自发耐受模型。CD4+CD25+Treg可能参与自发免疫耐受的形成。     

多发性骨髓瘤患者外周血Th1/Th2及CD4~+CD25~+Tregs的表达分析

目的:检测多发性骨髓瘤(MM)患者外周血T辅助细胞亚群(Th1/Th2)及调节性T细胞(CD4+CD25+Tregs)数量和比例的变化,探讨其T细胞免疫功能状态及临床意义。方法:流式细胞术(FCM)检测31例MM患者及20例健康志愿者外周静脉血Th1/Th2及CD4+CD25+Tregs的比例并分析比较。结果:(1)II、III期MM患者Th1细胞比例较对照组降低,III期Th2细胞比例较对照组及I期降低,差异具有显著性;II、III期MM患者CD4+CD25+、CD4+CD25high、CD4+CD25highCD127low细胞比例均高于正常组,III期CD4+CD25high、CD4+CD25highCD127low较I期增高,差异具有显著性。(2)化疗后复发组MM患者Th1细胞比例较对照组降低,初诊组及化疗后复发组Th2细胞比例较对照组及稳定期组降低,差异具有显著性;初诊组及化疗后复发组CD4+CD25+、CD4+CD25high、CD4+CD25highCD127low细胞比例均高于正常组,复发组CD4+CD25+、CD4+CD25high、CD4+CD25highCD127low明显高于稳定组及初诊组,差异具有显著性。(3)相关性分析Th1、Th2细胞与CD4+CD25+Tregs存在不同程度的负相关(均P0.05或0.01)。结论:MM患者外周血Th1、Th2细胞比例降低,调节性T细胞比例增高,两者相互调节,并与疾病临床分期、病情进展相关,对指导治疗也有一定的价值。     

肺结核患者外周血CD4~+和CD8~+记忆性T细胞亚群、IL-17、IL-27表达的初步探讨

目的:探讨肺结核患者外周血CD4+和CD8+记忆性T细胞亚群及白细胞介素17(Interleukin-17,IL-17),IL-27的表达。方法:采用流式细胞术检测肺结核患者组外周血CD4+和CD8+记忆性T细胞,患者组按治疗史分为初治组,复治组;按痰涂片抗酸染色分为痰涂阳性组,痰涂阴性组。初治组8例为凡既往未用过抗结核药物治疗或用药时间少于一个月的新发病例;复治组22例为凡既往应用抗结核药物一个月以上的新发病例、复发病例、初治治疗失败病例等;痰涂阳组9例为痰涂片抗酸染色阳性;痰涂阴组21例为痰涂片抗酸染色阴性。ELISA法检测IL-17,IL-27。结果:①与健康对照组比较:患者组CD4+效应型记忆性T细胞均显著增高(P<0.05),初治组与涂阴组CD8+效应型记忆性T细胞均显著降低(P<0.05),复治组IL-17显著降低(P<0.05),而IL-27显著增高(P<0.05)。②与初治组比较:复治组CD4+中央型记忆性T细胞显著降低(P<0.05),而CD8+效应型记忆性T细胞显著增高(P<0.05),IL-17显著降低(P<0.05),IL-27显著增高(P<0.05)。③与涂阴组比较:涂阳组CD4+中央型记忆性T细胞显著降低(P<0.05),CD8+效应型记忆性T细胞显著增高(P<0.05),CD8+中央型记忆性T细胞显著降低(P<0.05)。④Spearman相关性分析显示:IL-17与IL-27呈正相关(P<0.05),记忆性T细胞亚群与IL-17,IL-27水平无显著相关性(P>0.05)。结论:肺结核患者外周血CD4+效应型记忆性T细胞的表达可望作为TB初步诊断的观察指标,CD4+中央型记忆性T细胞和CD8+效应型记忆性T细胞的表达均可望作为TB患者的临床分组依据,TB外周血IL-17、IL-27水平可望用于判断TB的炎症程度。     

八色流式细胞术检测人外周血BCG特异性效应型记忆CD4+T细胞的表型特征

目的:检测BCG刺激后,PPD+正常人外周血中细胞因子产生及其亚群.方法:分离PPD+正常人外周血单个核细胞(PBMC),BCG刺激后检测CD4+和CD8+T细胞细胞因子分泌,并用八色流式细胞术分析BCG特异性T细胞亚群.结果:BCG刺激PBMC后,主要是CD4+T细胞分泌Th1细胞因子(IFN-γ、IL-2和TNF-α),而CD8+T细胞几乎不产生细胞因子.进一步分析分泌细胞因子的细胞亚群,主要是CD4+CD45RO+ CD62L(-)CD27(-)和CD4+ CD45RO+ CD62L(-)CD27+分泌细胞因子.结论:BCG刺激PPD+正常人外周血PBMC后,主要诱导CD4+T细胞分泌细胞因子,且该细胞表现出CD4+CD45RO+ CD62L(-)效应型记忆细胞特征,可能在预防结核感染中发挥重要作用.     

The quantitative and qualitative defect of CD4+ CD45RO+ memory-type T cells are involved in the abnormality of TH1 immunity in atopic dermatitis patients.

Peripheral blood mononuclear cells (PBMCs) obtained from atopic dermatitis (AD) patients produced low levels of IFN-gamma in response to Dermatophagoides farinae antigen (Der f Ag) plus IL-2 or OKT3 MoAb in contrast with PBMCs obtained from healthy donors. The reduced IFN-gamma production in AD patients' T cells appeared to be derived from the defect of CD4+ T cells but not CD8+ T cells. Indeed, from the cytoplasmic staining analysis of cytokines, it was demonstrated that the frequency of IFN-gamma producing CD4+ T cells (TH1 cells) in AD patients was markedly lower than that of healthy donors. From the phenotypic analysis using flow cytometry, it was also found that the number of CD4+ CD45RO+ memory type T cells was significantly reduced in AD patients compared with that of healthy donors. In addition to quantitative defect of memory type CD4+ T cells, functional defect of CD4+ CD45RO+ memory type T cells was also demonstrated in AD patients. Enriched CD4+ CD45RO+ T cells obtained from AD patients, who exhibited greatly reduced delayed-type hypersensitivity (DTH) response in tuberculin test, showed no significant TH1 immunity in terms of IFN-gamma production by stimulation with OKT3 MoAb or purified protein derivative (PPD). Thus, the immunological abnormality of TH1 immunity in AD patients appeared to be induced in concomitant with both the quantitative and qualitative defect of memory type CD4+ T cells.     

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.     

Immune memory in CD4+ CD45RA+ T cells.

This study addresses the question of whether human peripheral CD4+ CD45RA+ T cells possess antigen-specific immune memory. CD4+ CD45RA+ T cells were isolated by a combination of positive and negative selection. Putative CD4+ CD45RA+ cells expressed CD45RA (98.9%) and contained < 0.1% CD4+ CD45RO+ and < 0.5% CD4+ CD45RA+ CD45RO+ cells. Putative CD45RO+ cells expressed CD45RO (90%) and contained 9% CD45RA+ CD45RO+ and < 0.1% CD4+ CD45RA+ cells. The responder frequency of Dermatophagoides pteronyssinus-stimulated CD4+ CD45RA+ and CD4+ CD45RO+ T cells was determined in two atopic donors and found to be 1:11,314 and 1:8031 for CD4+ CD45RA+ and 1:1463 and 1:1408 for CD4+ CD45RO+ T cells. The responder frequencies of CD4+ CD45RA+ and CD4+ CD45RO+ T cells from two non-atopic, but exposed, donors were 1:78031 and 1:176,903 for CD4+ CD45RA+ and 1:9136 and 1:13,136 for CD4+ CD45RO+ T cells. T cells specific for D. pteronyssinus were cloned at limiting dilution following 10 days of bulk culture with D. pteronyssinus antigen. Sixty-eight clones were obtained from CD4+ CD45RO+ and 24 from CD4+ CD45RA+ T cells. All clones were CD3+ CD4+ CD45RO+ and proliferated in response to D. pteronyssinus antigens. Of 40 clones tested, none responded to Tubercule bacillus purified protein derivative (PPD). No difference was seen in the pattern of interleukin-4 (IL-4) or interferon-gamma (IFN-gamma) producing clones derived from CD4+ CD45RA+ and CD4+ CD45RO+ precursors, although freshly isolated and polyclonally activated CD4+ CD45RA+ T cells produced 20-30-fold lower levels of IL-4 and IFN-gamma than their CD4+ CD45RO+ counterparts. Sixty per cent of the clones used the same pool of V beta genes. These data support the hypothesis that immune memory resides in CD4+ CD45RA+ as well as CD4+ CD45RO+ T cells during the chronic immune response to inhaled antigen.     

A high frequency of peripheral blood NKG2D+NK and NKT cells in euthyroid patients with new onset hashimoto’s thyroiditis—a pilot study

Hashimoto’s thyroiditis (HT) is a T cell-mediated autoimmune disease. However, little is known about the role of different subsets of natural killer (NK) and natural killer T (NKT) cells at the early stage of the HT process. A total of 45 euthyroid patients with new onset HT and 40 age/gender-matched healthy controls (HC) were examined for the frequency of different subsets of NK and NKT cells and their function by flow cytometry. In comparison with that in HC, significantly higher percentages of peripheral blood CD3-CD56+ NK, NKG2D+, NKp30+ NK and NKT cells, but significantly lower percentages of NKG2A+, KIR2DL3+ inhibitory NK and NKT cells were detected in the HT patients. Furthermore, the percentages of NKG2D+ NK cells were correlated positively with the concentrations of serum anti-thyroid peroxidase antibody (TPOAb) in the HT patients. Moreover, the percentages of inducible IFN-γ and CD107a+ NK cells in the HT patients were significantly higher than those in HC. Our data suggest that activated NK cells may participate in the early pathogenic process of HT.     

Interferon-beta therapy reduces CD4+ and CD8+ T-cell reactivity in multiple sclerosis

Therapy with interferon-beta (IFN-beta) has well-established clinical effects in multiple sclerosis (MS), albeit the immunomodulatory mechanisms are not fully understood. We assessed the prevalence and functional capacity of CD4+ and CD8+ T cells in healthy donors, and in untreated and IFN-beta-treated MS patients, in response to myelin oligodendrocyte glycoprotein (MOG). The proportion of CD45RO+ memory T cells was higher in MS patients than in healthy donors, but returned to normal values upon therapy with IFN-beta. While CD45RO+ CD4+ T cells from all three groups responded to MOG in vitro, untreated patients showed augmented proliferative responses compared to healthy individuals and IFN-beta treatment reduced this elevated reactivity back to the values observed in healthy donors. Similarly, the response of CD45RO+ CD8+ T cells to MOG was strongest in untreated patients and decreased to normal values upon immunotherapy. Overall, the frequency of peripheral CD45RO+ memory T cells ex vivo correlated with the strength of the cellular in vitro response to MOG in untreated patients but not in healthy donors or IFN-beta-treated patients. Compared with healthy individuals, responding CD4+ and CD8+ cells were skewed towards a type 1 cytokine phenotype in untreated patients, but towards a type 2 phenotype under IFN-beta therapy. Our data suggest that the beneficial effect of IFN-beta in MS might be the result of the suppression or depletion of autoreactive, pro-inflammatory memory T cells in the periphery. Assessment of T-cell subsets and their reactivity to MOG may represent an important diagnostic tool for monitoring successful immunotherapy in MS.     

CCR4 is an up-regulated chemokine receptor of peripheral blood memory CD4+ T cells in Crohn's disease

Several chemokine receptors are expressed selectively on the surface of T cells depending on their polarization. The aim of this study was to characterize chemokine receptor expression in peripheral blood memory T cells in Crohn's disease (CD) and ulcerative colitis (UC), and to correlate the expression with disease activity. Peripheral blood mononuclear cells (PBMCs) were obtained from 24 patients with CD, 30 patients with UC, 24 normal controls and 10 disease controls. PBMCs were stained by anti-CCR3, CCR4, CCR5, CXCR3, CD4, CD8, CD45RO and beta 7 integrin, and the expression of the chemokine receptors were determined by flow cytometry. CCR4 expression on memory T cells was significantly lower in UC than in CD or normal controls, and that of memory CD4+ T and beta 7(high) memory CD4+ T cells was significantly higher in CD than in UC or normal controls. CCR4 expression on memory CD4+ T cells exhibited significant positive correlation with disease activity in CD, and this decreased significantly after treatment. Such a decrease was not found in the disease controls. CCR5 and CXCR3 expression on memory CD8+ T cells was significantly lower in CD than in normal controls. CXCR3 expression on beta 7(high) memory CD4+ T and CXCR3 expression on memory CD8+ T cells were lower in UC than in normal controls. These findings suggest that in peripheral blood memory T cells, chemokine receptor expression is different between CD and UC. Enhancement of CCR4 and suppression of CCR5 and CXCR3 seem to be the characteristic chemokine receptor profile in peripheral blood memory T cells of CD.     

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.     

Active Crohn's Disease Patients Show a Distinctive Expansion of Circulating Memory CD4+CD45RO+CD28null T Cells

In a previous study we found an expansion of circulating memory (CD45RO(+)) CD4(+) T cells in patients with Crohn's disease (CD). The aim of this work was to investigate the phenotypic and functional characteristics of this T-cell subset in CD. We analyzed in peripheral blood CD4(+)CD45RO(+) T cells from CD patients the expression of surface markers associated to immune activation, costimulation, and apoptosis. In sorted CD4(+)CD45RO(+) T cells apoptosis was quantified by fluorescent annexin V binding. Healthy subjects and patients with ulcerative colitis and acute bacterial enterocolitis served as control groups. An increased percentage of memory CD4(+)CD45RO(+) T cells lacking the expression of costimulatory receptor CD28 was detected in patients with active CD when compared to the other groups evaluated. This expanded CD4(+)CD45RO(+)CD28(null) T-cell subset expressed mostly the effector-cell marker CD57(+). Both CD28 downregulation and CD57 expression correlated to CDAI and surrogate markers of disease activity. These phenotypic changes observed on CD4(+)CD45RO(+) T cells from active CD returned to values similar to healthy controls after clinical remission. Moreover, this memory CD28(null) T-cell subset might express more intracytoplasmic TNF and IFN-gamma than their CD28(+) counterpart. Significantly lower frequencies of memory CD4(+)CD45RO(+) T cells expressing CD95 apoptosis receptor were found in patients with active CD. Moreover, sorted CD4(+)CD45RO(+)and CD4(+)CD45RO(+) CD28(null) T cells from patients with active CD exhibited a lower apoptotic rate than that found in healthy controls and inactive CD patients. According to our data, circulating T lymphocytes from active CD patients show distinctive phenotypic and functional changes, characterized by an expansion of memory CD4(+)CD45RO(+)CD28(null) T cells expressing effector-associated cell surface molecules and displaying enhanced resistance to apoptosis.