慢性乙型肝炎患者外周血CD45RA+,CD45RO+T淋巴细胞亚群的特点及临床意义

目的 探讨慢性乙型肝炎患者外周血CD4＋CD45RA＋，CD4＋CD45RO＋，CD8＋CD45RA＋和CD8＋CD45RO＋T淋巴细胞亚群的特点及及其与肝病病情的关系．方法 采集46例轻中度慢性乙型肝炎患者、58例重度慢性乙型肝炎患者和30例健康人的外周抗凝血，应用流式细胞技术三色荧光分析法对其外周血中CD4＋CD45RA＋，CD4＋CD45RO＋，CD8＋CD45RA＋和CD8＋CD45RO＋T淋巴细胞亚群进行检测，结果轻中、重度慢性乙型肝楚患者与正常人相比．其外周血中CD4＋，CD8＋T细胞均无明显改变；CD8＋CD45RA＋T细胞均明显降低，CD8＋CD45RO＋T细胞均明显增高，而CD4＋CD45RA＋，CD4＋CD45RO＋T细胞均无明显改变；重度慢性乙型肝炎患者与轻中度慢性乙型肝炎患者相比，CD8＋CD45RA＋T细胞明显降低（P〈0．05），CD8＋CD45RO＋T细胞明显升高（P〈0．05）．结论乙型肝炎慢性化过程中，CD8＋CD45RO＋T细胞起重要作用且与慢性乙型肝炎患者病情的进展呈正相关；检测CD4＋CD45RA＋．CD4＋CD45RO＋．CD8＋CD45RA＋和CD8＋CD45RO＋T淋巴细胞亚群比检测CD4＋和CD8＋T细胞亚群能使我们更加正确、充分、全面地了解慢性乙型肝炎的发病机制和预后，从而有效地指导临床治疗。     

关于CD45RA/CD45RO分子的功能研究

CD45RA和CD45RO是白细胞共同抗原的两种异型.CD45RA 和CD45RO T淋巴细胞在表型、功能等各方面均不同,了解其亚群的变化可能有助于了解许多疾病的发病机制、临床状态及预后.     

CD4~＋CD45~＋T细胞在反复上呼吸道感染患儿的表达及其与球蛋白的关系

目的：探讨反复上呼吸道感染（FURI）的患儿的CD4＋CD45＋T细胞两个亚群与球蛋白的特点。方法：收集现症及恢复期FURI患儿各26例,选取健康体检者18例作为对照;检测外周血CD4＋CD45RA＋及CD4＋CD45RO＋T细胞亚群的含量,并测定免疫球蛋白IgG、IgA及IgM的含量;且进行相关性分析。结果：健康组的CD4＋CD45RA＋T细胞显著高于恢复组,且恢复组高于现症组（P〈0.05）,但CD4＋CD45RO＋T细胞恰好相反,亦即现症组〉恢复组〉健康组（P〈0.05）;IgG及IgA的变化趋势为：现症组〈恢复组〈健康组,IgM的变化趋势与IgG及IgA相反;Pearson相关性分析显示CD4＋CD45RA＋及CD4＋CD45RO＋T细胞亚群呈显著负相关性（r=-0.791,P〈0.05）,CD4＋CD45RO＋T细胞与IgM呈正相关性,CD4＋CD45RA＋T细胞与IgG及IgA均呈显著正相关性（均为P〈0.01）。结论：反复上呼吸道感染患儿的CD4＋CD45RA＋/CD4＋CD45RO＋T细胞平衡向后者倾斜,且伴随体液免疫免疫失调,是该病的一个重要特征。     

流式细胞术检测拉米夫定对慢性乙型肝炎患者T细胞亚群的影响

目的研究拉米夫定对慢性乙型肝炎（CHB）患者细胞免疫功能的影响.方法采用流式细胞术检测50例CHB患者在服用拉米夫定前后外周血T细胞亚群,同时检测45例健康体检者外周血T细胞亚群作为对照.结果CHB患者在使用拉米夫定后,CD4 T细胞百分比较使用前明显升高（P〈0.05）,CD8 T细胞百分比明显下降（P〈0.05）,CD4/CD8明显升高（P〈0.05）.结论拉米夫定可改善CHB患者的细胞免疫功能.     

精神分裂症患者T淋巴细胞上CD226分子的表达研究

目的 通过检测T细胞上CD226分子的表达情况来阐明SCH患者T细胞的活化状态及功能．方法 将精神分裂症患者和正常对照群的外周血单个核细胞各分为植物血凝素(PHA)刺激组与非刺激组,用双色免疫荧光染色和流式细胞术检测T细胞上CD226分子的表达百分率,观察PHA刺激对T细胞表达CD226的影响．结果 1)无论是否给予PHA刺激,SCH患者外周血T淋巴细胞上CD226阳性百分率均显著高于正常对照组．2)给予PHA刺激后,SCH患者和正常对照者外周血T淋巴细胞上CD226分子的表达均显著增高;在升高幅度上,SCH患者CD226表达增长值显著低于正常对照组．3)在患者与对照组二者之间,未发现CD4,CD8 2个T细胞亚群之间CD226表达百分率存在显著性差异．4)精神分裂症患者CD226的表达与性别无关．结论 SCH患者外周血T淋巴细胞上CD226分子的表达百分率显著升高,细胞敏感性增强．在SCH患者体内。大量T淋巴细胞已处于活化状态．SCH患者体内存在某种非正常刺激因素。     

乳腺癌患者细胞免疫指标的检测及意义

目的检测乳腺癌患者外周血T淋巴细胞总数及CD4~+T细胞、CD8~+T细胞、CD45RA~+T细胞、CD45RO~+T细胞等T淋巴细胞亚群的百分率,用以评价患者的免疫状态.方法选择女性原发性乳腺肿瘤患者50例为病例组,并以病理检查的TNM分期结果做进一步分组,其中乳腺癌Ⅰ期27例,乳腺癌Ⅱ+Ⅲ期23例;选择女性健康体检者40例为健康对照组.应用流式细胞仪,分别检测各组外周血T淋巴细胞亚群的数量,统计分析各组检测结果的差异性.结果乳腺癌Ⅱ+Ⅲ期组CD3~+T细胞和CD4~+T细胞百分率明显低于正常对照组和乳腺癌Ⅰ期组,差异具有统计学意义(P0.05);乳腺癌Ⅰ期组CD45RA~+T细胞明显低于正常对照组,乳腺癌Ⅱ+Ⅲ期组CD45RA~+T细胞明显低于乳腺癌Ⅰ期组,差异具有统计学意义(P0.05);乳腺癌Ⅰ期组CD45RO~+T细胞明显高于正常对照组,乳腺癌Ⅱ+Ⅲ期组CD45RO~+T细胞明显高于乳腺癌Ⅰ期组,差异具有统计学意义(P0.05).结论T细胞亚群检测是评价肿瘤患者细胞免疫功能的重要指标,具有重要的临床应用价值.乳腺癌患者免疫功能与肿瘤恶变的发生、发展、临床分期有一定相关性,随着病情的进展,机体免疫功能呈现下降趋势.     

清疣饮对扁平疣患者外周血淋巴细胞亚群的影响

目的 探讨清疣饮对扁平疣患者外周血CD4 T细胞、CD8 T细胞亚群的影响.方法 应用APAAP法检测外周血淋巴细胞亚群.结果 患者在治疗中CD8 T细胞水平提高,CD4 T/CD8 T比值降低,治疗后CD4 T/CD8 T比值恢复正常.结论 清疣饮对扁平疣患者外周血T细胞亚群有调节作用.     

IFN-α治疗对慢性丙型肝炎患者CD8~+T细胞亚群Tim-3表达水平的影响

为探讨应用IFN-α治疗和未治疗的慢性丙型肝炎患者外周血CD8+T细胞亚群细胞频数及各亚群上Tim-3表达的变化。采用流式细胞术检测IFN-α治疗和未治疗的慢丙肝患者外周血中CD8+T细胞及各亚群频数及膜表面Tim-3表达水平的方法;q T-PCR检测血清中HCV-RNA水平;Spearman相关性分析CD8+T细胞频数、Tim-3表达与HCV-RNA之间的相关性。结果显示,慢丙肝患者外周血CD8+T细胞频数较健康对照组、IFN-α治疗组显著降低(P0.01)。初始T细胞明显增加(P0.01)。TCM、TEM细胞分布频率降低(P0.01)。经IFN-α治疗后,CD8+T细胞百分率上升(P0.05),初始T细胞数量下降(P0.01),TCM、TEM细胞频数均升高(P0.01)。三组人群TEMRA细胞频数无统计学差异。与健康对照组、IFN-α治疗组相比,慢丙肝患者CD8+T细胞及各亚群Tim-3表达水平均有上调(P0.05)。经抗病毒治疗后,CD8+T细胞、Naive细胞、TEM细胞、TEMRA细胞亚群Tim-3表达明显降低(P0.05),TCM细胞亚群中Tim-3表达也有降低,但无统计学差异。Spearman相关性分析发现:慢丙肝患者外周血CD8+T细胞百分率与病毒载量呈反比(r=-0.3775,P0.01),而Tim-3表达水平与病毒载量正相关(r=0.6230,P0.0001)。由此可知,HCV感染慢性化时可出现CD8+T细胞亚群分布异常及各亚群Tim-3过表达。IFN-α通过调节各CD8+T细胞亚群分化状态,及下调各群细胞表面Tim-3的表达,促进HCV免疫清除。     

肿瘤患者外周血CD4+和CD8+T淋巴细胞TCR Vβ基因克隆化分析

目的探讨肿瘤患者T细胞抗原受体(TCR)Vβ基因克隆化改变特征.方法应用多引物巢式PCR技术检测肿瘤患者外周血CD4+T细胞和CD8+T细胞TCR Vβ基因22个亚家族的克隆化改变,与正常对照组比较,分析肿瘤患者TCR单克隆改变的特点.结果 CD8+T细胞TCRVβ基因亚家族单克隆改变的数量多于CD4+T细胞;肿瘤患者的CD4+T细胞中,只有Vβ2,Vβ7和Vβ8三个亚家族单克隆改变高于正常对照组(P0.01或P0.05),其他Vβ亚家族单克隆改变与正常对照组无明显差异.肿瘤患者的CD8+T细胞中,有14个Vβ亚家族单克隆改变均高于正常对照组(P0.01或P0.05);4组肿瘤患者中,CD4+T细胞和CD8+T细胞的TCR Vβ7亚家族的单克隆改变均明显高于正常对照组(P0.01或P0.05).结论通过检测TCR Vβ基因克隆化改变,可以初步了解T细胞对肿瘤的免疫应答状况.     

肝癌患者手术前后T细胞亚群的变化特点及其意义

目的:探讨肝癌患者手术前后外周血T淋巴细胞亚群的变化特点.方法:应用APAAP法测定30例肝癌患者手术前后的CD3、CD4和CD8细胞的阳性细胞百分率及其比值,并与正常对照组比较分析.结果:30例肝癌患者手术前CD3,CD4及CD4/CD8比值明显低于正常对照组,差异有显著性(P＜0.01),手术后CD4/CD8的比值有明显提高,差异也有显著性(P＜0.01),提示肝癌患者手术前后CD4/CD8比值有显著改变.结论:监测外周血CD4/CD8的比值可作为评价肝癌患者病情及手术后预后的一个参考指标.     

Association of CD2 and CD45 on human T lymphocytes

At least two membrane receptors have been defined through which human T lymphocytes can be induced to proliferate and differentiate, namely the CD3-Ti antigen receptor complex and the CD2 molecule. Monoclonal antibodies directed at either CD2 or CD3 induce intracellular second messenger production and subsequent protein phosphorylation. On most human non-B lymphocytes, CD3-Ti and CD2 are coexpressed and seem to be functionally interrelated. But there are minor subpopulations in which these receptor systems can transduce signals despite a mutually exclusive expression, indicating that CD3-Ti and CD2 can act independently of each other. This view is supported by the finding that most monoclonal antibodies directed at the CD45 molecules are strongly co-mitogenic with CD2 but not CD3 monoclonal antibodies. As the intracytoplasmic domains of CD45 have tyrosine phosphatase activity these functional effects could be explained by a physical association between CD2 and CD45. Using chemical crosslinking techniques, we now show that CD45 is linked to CD2 on the surface of human T lymphocytes.     

Interconversion of CD45R subsets of CD4 T cells in vivo

T lymphocytes express multiple forms of the leukocyte common antigen CD45, transcribed by alternative usage of leukocyte-common antigen exons 4-6. Species-specific monoclonal antibodies against restricted epitopes (CD45R) of the antigen subdivide CD4 T cells into reciprocal subsets expressing either the high molecular weight isoforms CD45RA or RB or a molecule in which exons 4-6 have been spliced out (CD45R0). CD45R+ or RB+ CD4 T cells are potent in graft-versus-host reactions, and interleukin-2 related activities, whereas the CD45R0+ subset responds in vitro to recall antigens and provides help for antibody synthesis. It is unclear whether CD45R subsets derive from separate lineages, or are products of unidirectional or reversible differentiation. We show by transferring CD45R+ or CD45R- allotype-marked CD4 T cells into athymic nude rats that both subsets routinely generate cells of the opposite phenotype with a function that follows phenotype, not parentage. The recent equation of CD45R subsets as maturation stages representing 'naive' and 'memory' T cells is difficult to reconcile with this finding.     

CD45在T细胞激活过程中的作用

CD45是免疫系统主要的跨膜酷氨酸磷酸酶,已经形成的共识认为,CD45的信号转导过程中单一的起着正调节作用,促进了生命信号向细胞内的传播,模型阐述了CD45在信号过程中的双重作用,为近期的试验提供了理论解释。     

Lifespan of human lymphocyte subsets defined by CD45 isoforms.

The lifespan of thymic-derived or T lymphocytes is of particular interest because of their central role in immunological memory. Is the recall of a vaccination or early infection, which may be demonstrated clinically up to 50 years after antigen exposure, retained by a long-lived cell, or by its progeny? Using the observation that T lymphocyte expression of isoforms of CD45 corresponds with their ability to respond to recall antigens, we have investigated the lifespan of both CD45R0 (the subset containing responders, or 'memory' cells) and CD45RA (the unresponsive, or 'naive' subset) lymphocytes in a group of patients after radiotherapy. Here we report rapid loss of unstable chromosomes from the CD45R0 but not the CD45RA pool. Immunological memory therefore apparently resides in a population with a more rapid rate of division. Differing survival curves for the two subsets are best described by a model in which there is also reversion in vivo from the CD45R0 to the CD45RA phenotype. Expression of CD45R0 in T cells may therefore be reversible.     

Tyrosine phosphatase CD45 is essential for coupling T-cell antigen receptor to the phosphatidyl inositol pathway

Stimulation of T lymphocytes through their antigen receptor (T-cell receptor; TCR) results in the activation of a tyrosine kinase and the generation of phosphatidyl inositol (PtdIns)-derived second messengers. Several reports have indicated that CD45, a haematopoietic cell-specific surface glycoprotein with tyrosine phosphatase activity in its cytoplasmic domain, is important in lymphocyte activation. To examine the possibility that CD45 might influence proximal signal transduction events through the TCR, we have isolated a variant of the human T-cell leukaemic line, HPB-ALL, which fails to express this phosphatase. Unlike cells expressing CD45, stimulation of the TCR in the CD45-negative cell does not result in PtdIns-derived second messengers. Reconstitution of CD45 expression restored early signalling events through the TCR. To localize the site of CD45 action, the human muscarinic type 1 receptor, which also activates the PtdIns second messenger pathway, was transfected into the CD45-negative cell. Although stimulation of the TCR failed to generate PtdIns-derived second messengers, there was normal activity of the PtdIns pathway when human muscarinic receptor type 1 was stimulated, despite the absence of CD45. These data indicate that CD45 influences a cellular component that is essential for effective coupling of the TCR to the PtdIns second messenger pathway.     

闪速存储器AT45D系列芯片的应用

介绍了ATMEL公司生产的大容量FLASH存储器AT45D系列芯片的内部结构、地址选择及控制方法.以AT45D161芯片为例,给出了单片机使用该芯片的电路设计和软件编程.