血小板活化因子及其受体与淋巴细胞

血小板活化因子 (plateletactivatingfactor,PAF)是一种具有强大生物活性的磷脂类介质 ,在生物体内与其特异性受体结合而发挥作用。本文主要综述了PAF对淋巴细胞功能的影响及相关作用机制的研究进展。B淋巴细胞及大多数B细胞株上存在组成性PAF受体 ,受到刺激后还可诱生性表达 ;PAF能直接促进B淋巴细胞免疫球蛋白的分泌 ;并能抑制B淋巴细胞的凋亡。T淋巴细胞及大多数T淋巴细胞株上没有PAF受体表达 ,一般不产生和代谢PAF ;PAF能引起T淋巴细胞的趋化反应。PAF参与NK细胞的趋化反应及杀伤肿瘤细胞。     

087 血小板活化因子及其受体与淋巴细胞

血小板活化因子(platelet activating factor，PAF)是一种具有强大生物活性的磷脂类介质，在生物体内与其特异性受体结合而发挥作用。本文主要综述了PAF对淋巴细胞功能的影响及相关作用机制的研究进展。B淋巴细胞及大多数B细胞株上存在组成性PAF受体，受到刺激后还可诱生性表达；PAF能直接促进B淋巴细胞免疫球蛋白的分泌；并能抑制B淋巴细胞的凋亡。T淋巴细胞及大多数T淋巴细胞株上没有PAF受体表达，一般不产生和代谢PAF；PAF能引起T淋巴细胞的趋化反应。PAF参与NK细胞的趋化反应及杀伤肿瘤细胞。     

血小板活化因子及其受体与淋巴细胞

血小板活化因子（platelet activating factor,PAF)是一种具有强大生物活性的磷脂类介质，在生物体内与其特异性受体结合而发挥作用。本文主要综述了PAF对淋巴细胞功能的影响及相关作用机制的研究进展。B淋巴细胞及大多数B细胞株上存在组成性PAF受体，受到刺激后还可诱生性表达；PAF能直接促进B淋巴细胞免疫球蛋白的分泌；并能抑制B淋巴细胞的凋亡。T淋巴细胞及大多数T淋巴细胞 株上没有PAF受体表达，一般不产生和代谢PAF；PAF能引起T淋巴细胞的趋化反应。PAF参与NK细胞的趋化反应及杀伤肿瘤细胞。     

烫伤大鼠血淋巴细胞bcl-2、bcl-x和bax的表达及作用

目的 :研究大鼠烫伤后外周血淋巴细胞的凋亡及其bcl 2家族基因的表达 ,以探讨烫伤后bcl 2家族基因的表达对细胞凋亡的调控。方法 :复制 30 %体表面积Ⅲ度烫伤大鼠模型 ;分离外周血淋巴细胞 ,TUNEL荧光标记 ,流式细胞仪分析细胞凋亡 ;提取总RNA ,采用RT PCR分析bcl 2家族调控基因的表达。结果 :外周血淋巴细胞凋亡在健康大鼠比例较低 ( 3.99± 1 .72 % ) ,但伤后各组 ( 3、6、1 2、2 4、4 8h依次分别为 8.5 8± 1 .5 3%、8.38± 1 .81 %、2 0 .77± 3.94 %、2 3.90± 3.92 %和 1 1 .2 1± 1 .35 % )均明显增加 (P <0 .0 1 ) ,以伤后…     

SLE患者淋巴细胞膜上IL-2R表达的动态分析

本实验采用Wu Tac单克隆抗体的间接荧光抗体法,动态观察了系统性红斑狼疮(SLE)患者和正常供血员(对照组)的外周血淋巴细胞经PHA刺激后,于不同时间(0、24、48、72小时)内细胞膜上白细胞介素2受体(IL-2R)的表达。结果表明在给予PHA刺激培养24、48和72小时后,与对照组比较SLE患者淋巴细胞的IL-2R表达明显下降,提示了SLE的T淋巴细胞反应性降低可能与被激活的T细胞表面IL-2R的表达功能缺陷有关。此结果将有助于进一步探讨SLE的免疫调节紊乱的发生机制。     

血小板膜Ts和淋巴细胞膜整合素含量与脑梗塞的关系

细胞粘附分子是细胞表面的糖蛋白,主要位于血管内皮细胞和血液中白细胞的表面。目前用流式细胞仪测定急性脑梗塞（ＣＩ）血浆中凝血酶敏感蛋白（ｔｈｒｏｍｂｏｓｐｏｎｄｉｎ,Ｔｓ）,整合素ＣＤ１８、ＣＤ２９的百分含量（下称含量）与脑梗塞形成机制及临床预后研究,尚未见报告。现将我们对６０例住院患者检测的结果报告如下。     

慢性乙型肝炎患者外周血淋巴细胞Fas和FasL的表达及临床意义

Ｆａｓ和ＦａｓＬ是介导细胞凋亡的主要系统 ,我们应用逆转录 ＰＣＲ方法 ,对 37例慢性乙型肝炎患者外周血淋巴细胞Ｆａｓ和ＦａｓＬ的表达进行检测 ,初步探讨其在慢性乙型肝炎患者活化诱导的外周血淋巴细胞凋亡中的作用。对象与方法病例来源 :我院 1998～ 1999年 37例慢性乙型肝炎患者 ,男 2 6例 ,女 11例 ,年龄 16～ 6 0岁。诊断按1995年全国传染病与寄生虫病学术会议修订的病毒性肝炎标准〔1〕。活动期 :ＡＬＴ >10 0Ｕ/Ｌ ,乙肝标志物 :ＨＢｓＡｇ、ＨＢｅＡｇ、ＨＢｃＡｂ阳性 ,ＨＢＶＤＮＡ阳性。排除ＨＡＶ、ＨＣＶ、ＨＤＶ、ＨＥＶ…     

人肝癌组织肿瘤浸润淋巴细胞穿孔素,Fas配体表达的研究

目的 研究肝癌组织肿瘤浸润淋巴细胞（ＴＩＬ）的穿孔素及Ｆａｓ配体（Ｆａｓ－Ｌ）表达情况，方法 应用原位杂交及免疫组化ＡＢＣ方法检测２０例病人原发性肝细胞癌组织的ＴＩＬ中穿孔素及Ｆａｓ－Ｌ的ｍＲＮＡ及其蛋白的表达情况。结果 ２０例肝癌病人中１６例，肝癌组织中ＴＩＬ表达穿孔素及Ｆａｓ－１，其中１例病人的绝大多数ＴＩＬ表达穿孔素及Ｆａｓ－１，该例病人手术后１年６个月仍未复发，除该例以外，其余１５例肝癌组     

bcl-2 EXPRESSION IN PLEURAL AND EXTRAPLEURAL SOLITARY FIBROUS TUMOURS

This study evaluated the immunoreactivity for bcl-2, a molecule involved in the control of programmed cell death, in cases of pleural (14) and extrapleural (2) solitary fibrous tumour (SFT), malignant mesotheliomas of different histological types, and a variety of extrapleural CD34-positive and CD34-negative spindle-cell tumours. In all SFTs, strong and diffuse immunostaining was demonstrated with anti-bcl-2 antibody, sharply contrasting with the complete lack of staining observed in all mesotheliomas. The specificity of immunodetection of bcl-2 in SFT was confirmed by immunoblot analysis, showing a band consistent with the bcl-2 protein. At extrapleural locations, strong bcl-2 immunoreactivity was observed in Schwannoma (2/3 cases), synovial sarcoma (4/4 cases), and all cases of CD34-positive gastrointestinal stromal tumour (GIST; 10/10 cases). Most sarcomas were bcl-2-negative. Lack of bcl-2 expression was demonstrated in tumours which can pose problems in the differential diagnosis of SFT and can exhibit haemangiopericytoma-like features, including haemangiopericytoma (3 cases), dermatofibrosarcoma protuberans (16 cases), and deep-seated fibrous histiocytoma (3 cases). The constitutive expression of bcl-2 in SFT widens the spectrum of available markers for these tumours, providing a useful adjunct to their differential diagnosis in difficult cases at pleural and extrapleural sites, and contributing to the understanding of their histogenesis and molecular pathogenesis. © 1997 by John Wiley & Sons, Ltd.     

Involvement of APO2 ligand/TRAIL in activation-induced death of Jurkat and human peripheral blood T cells

The interaction of Fas with Fas ligand (FasL) mediates activation-induced cell death (AICD) of T hybridomas and of mature T lymphocytes. The TNF/TNF receptor system also plays a significant role in AICD of mature T cells and in the maintenance of peripheral tolerance. We previously demonstrated that in human Jurkat leukemia cells, AICD is triggered mainly by the rapid release of preformed FasL upon TCR stimulation. In the present work, we show that the cytotoxic cytokine APO2 ligand (APO2L; also known as TRAIL) is constitutively expressed as an intracytoplasmic protein in Jurkat T cells and derived sublines. APO2L is also detected in fresh human peripheral blood mononuclear cells (PBMC) from a significant number of donors, and the amount of both FasL and APO2L substantially increases upon blast generation. A neutralizing anti-APO2L monoclonal antibody (mAb) partially suppresses the cytotoxicity induced by supernatants of phytohemagglutinin (PHA)-prestimulated Jurkat or human PBMC on non-activated Jurkat cells, indicating that APO2L is released by these cells and contributes to AICD. A combination of neutralizing anti-APO2L and anti-Fas mAb blocks around 60 % of the toxicity associated with supernatants from PHA-activated human PBMC. These results show that FasL and APO2L account for the majority of cytotoxic activity released during AICD, and suggest that additional uncharacterized factors may also contribute to this process.     

RCS大鼠感光细胞凋亡与 Fas蛋白表达

为了探讨遗传性视网膜变性时感光细胞凋亡及其基因调控机制 ,本研究对出生后 9、15、2 0、2 5、3 0、3 5、40、60 d的 RCS大鼠及同龄 SD大鼠各 4只的视网膜进行了 TU NEL 凋亡检测及 Fas蛋白免疫组织化学反应。结果表明 ,出生后 2 5～ 40 d,RCS大鼠视网膜外核层可见 TUNEL阳性的感光细胞核 ,TUNEL阳性细胞数到 3 5 d达高峰 ( P<0 .0 5 )。Fas蛋白免疫组织化学检测发现 ,RCS大鼠视网膜内核层在 15～ 40 d可见 Fas免疫阳性细胞 ,阳性细胞数以 2 5 d为最多 ( P<0 .0 5 ) ;外核层在 2 5 d也可见Fas蛋白免疫阳性反应 ,一直持续到 40 d;节细胞层在 15～ 40 d可见 Fas蛋白表达。到 60 d时则各层又都不见明显的 Fas蛋白阳性反应。本研究结果提示 ,在 RCS大鼠视网膜变性过程中 ,感光细胞发生凋亡 ,Fas蛋白高表达可能与感光细胞的凋亡有关     

低氧预处理对大鼠海马神经元缺氧耐受性和bcl-2表达的影响

采用免疫组织化学方法观察了低氧预处理对大鼠海马神经元缺氧耐受性和 bcl-2表达的影响。结果显示 ,经低氧预处理的海马神经元缺氧 -复氧后 bcl-2表达较对照组明显增强 ,神经元损伤程度减轻 ,神经元存活数明显高于对照组。本结果表明 ,低氧预处理可使海马培养神经元对缺氧产生耐受 ,增加缺氧 -复氧后神经元 bcl-2的表达。提高神经元存活数     

EARLY EXPRESSION OF bcl-2 PROTEIN IN THE ADENOMA–CARCINOMA SEQUENCE OF COLORECTAL NEOPLASIA

bcl-2 was originally identified as an oncogene involved in follicular lymphomas as a result of chromosomal translocation (14;18). It is now believed that bcl-2 is implicated in the regulation of cell death by inhibiting apoptosis and that its expression is not restricted to haematopoietic cells, but is also present in many epithelia and mesenchymal tissues. Recent studies have analysed the expression of this molecule in a variety of non-lymphoid malignancies including lung, breast, prostate, and nasopharyngeal carcinomas and neuroblastoma. In the present study, 50 colorectal adenomas, 10 hyperplastic polyps, and 142 carcinomas, including 25 arising from pre-existing adenomas, were examined using an antibody detecting the bcl-2 protein product. In non-neoplastic mucosa, bcl-2 was expressed in the crypt cells only, whilst the more differentiated surface epithelial cells lacked any demonstrable bcl-2. Forty-one of the 50 adenomas (82 per cent) and 48 of the 142 carcinomas were positive for bcl-2 expression. All hyperplastic polyps were negative. A reciprocal relationship was found between bcl-2 reactivity and p53 overexpression, as detected by DO7 antibody, in approximately 65 per cent of the cases. The bcl-2-positive/p53-negative subgroup showed a strong correlation ( P =0·0056) with negative lymph node status (Dukes' A and B), implying a less aggressive pathway of neoplastic transformation.     

EXPRESSION OF bcl-2 AND p53 IN DE NOVO AND EX-ADENOMA COLON CARCINOMA: A COMPARATIVE IMMUNOHISTOCHEMICAL STUDY

The development of colorectal carcinoma from adenomas is recognized as the dominant mechanism of colon carcinogenesis. However, early colon carcinomas are being increasingly detected which have no adenomatous elements in their vicinity, and which, despite their small size, already show submucosal invasion. Such tumours (so-called ‘ de novo ’ carcinomas) have renewed consideration of the de novo colorectal carcinogenesis pathway. The goal of this study was to evaluate the expression of tumour suppressor gene p53 and apoptosis control gene bcl-2 in de novo carcinomas, compared with early carcinomas developing in the background of an adenoma (ex-adenoma). Fifty cases each of de novo and ex-adenoma carcinomas (pT1) were studied. p53 expression was significantly higher in the de novo carcinomas than in the ex-adenoma carcinomas (62 per cent vs. 42 per cent), while bcl-2 tended to be weaker in the de novo than in the ex-adenoma carcinomas. These differences support the concept that de novo carcinomas are a unique pathological entity, with a phenotype reflecting their more aggressive behaviour.     

丁型肝炎病人肝组织Fas/FasL和HDAg表达

为研究丁型肝炎病人肝组织Ｆａｓ／ＦａｓＬ和ＨＤＡｇ表达及意义,采用免疫组化单,双标记技术,检测了４８例丁型型肝炎病人肝组织Ｆａｓ,ＦａｓＬ和ＨＤＡｇ表达,且以５４例乙型肝炎作对照,结果发现,Ｆａｓ以及肝细胞浆表达为主,ＨＤＡｇ以肝细胞核和胞浆表达为主,二抗原表达及分布呈一致性。     

肝癌中bcl-2和bax基因的表达及其关系

目的：为了探讨巨细胞凋亡基因在肝癌发生中的作用。方法：利用免疫组化ＡＢＣ法,检测了肝癌中细胞凋亡抑制基因ｂｃｌ－２,促细胞凋亡基因ｂａｘ的表达。结果：ｂｃｌ－２以及ｂａｘ的个体阳性率均比正常对照组有显著性提高;肝癌组中ｂｃｌ－２和ｂａｘ的表达呈正相关,但无显著性。结论：ｂｃｌ－２表达抑制细胞凋亡,导致肝癌发生;ｂａｘ表达促进细胞凋亡,使肿瘤维持在高殖状态 。     

二乙基己烯雌酚诱发成年仓鼠睾丸生精异常及对生精细胞表达bcl-2、P53和cadherin的影响

目的探讨在二乙基己烯雌酚(DES)诱发成年动物生精异常过程中,原癌基因bcl-2、p53及黏附分子cadherin在生精细胞中表达的变化,旨在阐明DES诱发生精异常的作用机理。方法成年雄性仓鼠皮下注射DES连续7d后,取其睾丸,进行光镜及电镜的观察和原癌基因bcl-2、p53及黏附分子cadherin的免疫组织化学染色。结果DES处理组的成年仓鼠睾丸生精细胞发育异常,bcl-2和p53表达量均比对照组有显著增加,并以精母细胞和圆形精子细胞较为明显。生精上皮中cadherin的表达比对照组有明显减少。结论DES增加精母细胞和圆形精子细胞表达bcl-2和p53;同时抑制cadherin表达,是诱发成年仓鼠生精异常的原因之一。     

Immunohistochemical detection of bcl-2 protein in thymoma

The protooncogene bcl -2 encodes a protein that inhibits apoptosis. The protein is expressed in most epithelial cells of the fetal thymic medulla but, to the best of our knowledge, no data are available on bcl-2 expression in thymoma. Expression of bcl-2 protein was analysed in 30 cases of thymoma by immunohistological staining of paraffin-embedded tissue. All cases were examined and classified according to the Salyer and Eggleston and the Müller-Hermelink classification. In four cases, the protooncogene bcl -2 was abnormally expressed in spindle cells of pure medullary thymoma, whereas the non-spindle cells in mixed and in cortical thymoma were negative. All the lymphocytes were also strongly positive in medullary thymoma while a few lymphocytes showed light staining in other thymomas.