颗粒酶在细胞凋亡中的作用

颗粒酶是CTL、NK细胞诱导细胞凋亡的一个重要相关因素。本文综述了颗粒酶的一般生物学特性及其细胞毒作用，以及某些因素对细胞凋亡的影响。     

颗粒酶在细胞凋亡中的作用

颗粒酶是CTL、NK细胞诱导细胞凋亡的一个重要相关因素。本文综述了颗粒酶的一般生物学特性及其细胞毒作用 ,以及某些因素对细胞凋亡的影响     

092 颗粒酶在细胞凋亡中的作用

颗粒酶是CTL、NK细胞诱导细胞凋亡的一个重要相关因素.本文综述了颗粒酶的一般生物学特性及其细胞毒作用,以及某些因素对细胞凋亡的影响.     

电磁脉冲诱导肺癌细胞株A549凋亡的研究

目的　研究电磁脉冲 (EMP)对肺癌细胞A5 4 9凋亡的影响。方法　以场强为 6× 10 4V/m的EMP辐照 5次 /2min ,然后采用细胞计数、MTT、流式细胞术及免疫组化染色的图像分析 ,观察EMP对肺癌细胞A5 4 9的损伤作用 ,所有数据经SPSS8 0软件进行分析。结果　EMP可明显抑制肺癌细胞A5 4 9的增殖与活力。流式细胞术证明 ,A5 4 9细胞发生明显的凋亡。免疫组化的图像分析表明 ,伴有不同程度的Bcl 2蛋白表达的下调及P5 3蛋白表达的上调。结论　EMP可诱导肺癌细胞A5 4 9的凋亡。Bcl 2及P5 3蛋白参与了A5 4 9细胞的凋亡过程     

颗粒酶B直接裂解部分断裂的基因组DNA--颗粒酶B诱导细胞凋亡新途径

目的：颗粒酶B(Granzyme B，GraB)对核内物质具亲和力，体外除去核膜的细胞核中可观察到大量GraB聚积，观察GraB是否直接作用于基因组DNA。方法：通过抽提人外周血淋巴细胞总RNA，进行RT-PCR克隆GraB cDNA，构建GraB原核表达载体，用限制性酶切和DNA测序进行鉴定；异丙基-1-硫代-β-呋喃半乳糖苷(IPTC)诱导表达，通过聚丙烯酰胺凝胶电泳(SDS-PAGE)分析表达产物。表达产物经亲和层析纯化后，观察其对基因组DNA的功能。结果：表达产物以可溶性分子形式存在于菌体中，具有良好的抗原性和特异性，特异性底物检测有活性，且具有直接作用于部分断裂的基因组DNA，使其发生进一步裂解的活性。结论：Grab直接作用于部分断裂的基因组DNA，这可能是GraB诱导细胞凋亡新的作用途径。     

穿孔素与颗粒酶B在鼻NK/T细胞淋巴瘤诊断中的意义

目的　检测鼻NK/T细胞淋巴瘤中的穿孔素、颗粒酶B表达分布情况 ,为临床治疗和预后判断提供依据。方法　运用免疫组化S P法检测 11例鼻NK/T细胞淋巴瘤中穿孔素、颗粒酶B的表达和分布情况 ;同时与组织芯片中其他类型淋巴瘤进行比较研究 ,10例淋巴组织反应性增生作为对照。结果　 11例鼻NK/T细胞淋巴瘤中均见穿孔素和颗粒酶B过度表达。以 6 0例淋巴瘤制成组织芯片的 4 2例B细胞淋巴瘤中见 11例少许穿孔素和 14例少许颗粒酶B阳性表达细胞散在分布于瘤细胞间 ,10例外周T细胞淋巴瘤中 8例少许表达穿孔素和 9例少许表达颗粒酶B。 2例间变性大细胞淋巴瘤见少许穿孔素和颗粒酶B阳性表达细胞。 2例霍奇金淋巴瘤阴性。NK/T细胞淋巴瘤的穿孔素和颗粒酶B表达程度与T、B淋巴瘤比较 ,差异有显著性 (P <0 0 1)。结论　穿孔素和颗粒酶B是鉴定活化的细胞毒性细胞的免疫标记物 ,可作为NK/T细胞淋巴瘤的诊断性标记物 ;其在外周T细胞淋巴瘤和B细胞淋巴瘤中的表达 ,反映了机体存在抗肿瘤的免疫反应机制。     

人外周血NK细胞在细胞因子刺激下扩增后穿孔素、颗粒酶B基因表达的变化

目的 探讨经过纯化及在多种细胞因子的作用下扩增后的NK细胞,其穿孔素(per-furin)、颗粒酶B(granzyme B)表达水平的改变与细胞杀伤率的关系.方法 应用竞争性定量RT-PCR方法 检测了8例供者纯化、扩增后NK细胞的穿孔素、颗粒酶B基因表达水平,同时检测其对K562细胞的杀伤率.结果 经纯化、扩增后的NK细胞,在多种细胞因子作用下穿孔素和颗粒酶B的基因表达水平明显提高,且.IL-2+IL-15组、IL-2+IL-12+IL-15组基因的表达量均显著高于其他组,NK细胞对K562的杀伤率结果 与基因表达水平一致.结论 应用细胞因子后可使NK细胞的穿孔素、颗粒酶B基因表达水平明显提高,同时提高了NK细胞的杀伤功能.     

颗粒酶B和穿孔素免疫组织化学检测诊断肝移植急性排斥反应的敏感性与特异性

目的　探讨颗粒酶B和穿孔素两种免疫活化分子在肝移植急性排斥诊断中的作用,及其与Banff急性排斥反应组织学诊断标准之间的对应关系。方法　在常规组织学诊断基础上,将41份肝穿刺标本用颗粒酶B与穿孔素单克隆抗体进行免疫组织化学EnVision二步法标记,IPP图像分析软件计算阳性细胞数/mm2 作为免疫活化细胞指数(AI),以组织学诊断作为评判有无急性排斥反应的标准。结果　在41份肝穿刺标本中,组织学诊断为急性排斥反应21份,缺乏急性排斥反应组织学改变20份。急性排斥反应组颗粒酶B与穿孔素AI值显著高于无排斥反应组(P<0. 001),中重度排斥反应组AI值显著高于轻度及其非确定性排斥反应组(P<0. 001)。与组织学诊断比较,颗粒酶B的敏感性、特异性、阳性预测值、阴性预测值及诊断一致率分别达到90. 0%、95. 2%、94. 7%、90. 9%以及92. 7%;穿孔素的各指标也分别达到80. 0%以上。结论　颗粒酶B与穿孔素是急性排斥反应免疫效应细胞活化标志,在临床肝移植急性排斥反应时表达明显升高,作为组织学诊断急性排斥反应的辅助指标具有相当高的敏感性及特异性,可用于肝移植后肝穿刺标本的鉴别诊断。     

雷公藤甲素对非小细胞肺癌细胞系A549增殖的抑制和凋亡的诱导

目的探讨雷公藤甲素(TP)通过调控趋化因子受体4(CXCR4)基因表达对人非小细胞肺癌(A549)细胞增殖和凋亡的影响。方法实验分为4组:对照组、TP组(100 nm/L TP处理细胞)、CXCR4+TP组(转染质粒及TP处理细胞)和NC+TP组(转染空载质粒及TP处理细胞)。RT-qPCR和Western blot检测CXCR4表达以及转染效果;MTT法检测细胞增殖;AnnexinⅤ-FITC/PI双染色法检测细胞凋亡;Western blot检测增殖及凋亡相关蛋白表达。结果雷公藤甲素能够抑制A549细胞中CXCR4 mRNA和蛋白的表达(P<0. 05)。雷公藤甲素可抑制A549细胞增殖,诱导其凋亡(P<0. 05)。转染pc DNA-CXCR4能够上调CXCR4 mRNA和蛋白的表达(P<0. 05)。上调CXCR4的表达能够部分逆转雷公藤甲素对A549细胞增殖抑制和凋亡诱导的作用(P<0. 05)。结论雷公藤甲素可能通过下调CXCR4的表达抑制A549细胞增殖,诱导细胞凋亡。     

抗菌肽merecidin诱导人肺腺癌细胞系A549凋亡

目的探讨抗菌肽merecidin对人肺癌细胞系A549的作用及其机制。方法实验分为对照组(Ctrl)、顺铂干预组(cisplatin 40μmol/L)、merecidin干预组(merecidin 25/35μmol/L)、caspase抑制剂组(z-VAD-fmk)、caspase抑制剂+merecidin干预组(z-VAD-fmk+merecidin 25/35μmol/L)。MTT法检测细胞增殖,annexin V/PI双染法检测细胞凋亡,Western blot检测caspase-3、8、9、激活型caspase-3、Bcl-2和Bax蛋白表达。结果抗菌肽merecidin明显抑制A549细胞增殖(P0.05),merecidin处理24 h后的IC_(50)值为34.8μmol/L。与Ctrl组相比,merecidin干预组的凋亡率显著升高(P0.05);与merecidin干预组相比,caspase抑制剂+merecidin干预组的凋亡率并没有下降。caspase-3、8、9蛋白表达无显著变化且未检测到激活型caspase-3蛋白表达。Bcl-2蛋白表达下调(P0.05)及Bax蛋白表达增多(P0.05)。结论抗菌肽merecidin可以抑制人肺腺癌细胞A549的增殖并诱导其凋亡。     

Cleavage of FLICE (caspase-8) by granzyme B during cytotoxic T lymphocyte-induced apoptosis

Cytotoxic T lymphocytes induce apoptosis in target cells through the CD95(APO-1/Fas) and the perforin/granzyme B (GrB) pathway. The exact substrate of GrB in vivo is still unknown, but to induce apoptosis GrB requires the activity of caspases in target cells. We show here that in HeLa target cells induction of apoptosis through the perforin/GrB pathway resulted in minor direct cleavage of CPP32 (caspase-3) by GrB. Most caspase-3 cleavage resulted from activation of an upstream caspase. Moreover, target cells derived from caspase-3^?/? mice displayed GrB-induced poly(ADP-ribose) polymerase (PARP) cleavage with only partially reduced efficiency compared to wild-type target cells. This indicates that other PARP-cleaving caspases can be activated during perforin/GrB-induced cell death. In contrast to caspase-3, FLICE (caspase-8) was directly cleaved by GrB in HeLa cells. We therefore conclude that FLICE not only plays a central role in CD95(APO-1/Fas)-induced apoptosis but can also be directly activated during perforin/GrB-induced apoptosis.     

人外周血NK细胞亚群、表型和生物学特征

目的：探讨人外周血NK细胞的异质性和生物学特征。方法：利用多种标记抗体进行细胞表面和细胞内细胞毒效应分子染色，再利用流式细胞仪在单个细胞水平上分析NK细胞亚群的多样性和生物学特征。结果：NK细胞可分为CD56^ 、CD56^ ’CD16^ 和CD16^ 三个亚群。所有CD56^ NK细胞均表达CD95，但表达水平的高(CD95^bright)和低(CD95^dim)不同。在CD95^bright和CD8^ 细胞亚群中有43．5％的细胞同时表达颗粒酶B和穿孔素。而CD56^ CD16^ 和CD16^ 细胞表达CD95均为CD95^bright，同时表达颗粒酶B(83．6％)和穿孔素(89．8％)。结论：NK细胞乃异质性群体，随着CD56表达减少和CD16表达增加。其生物效应功能逐渐成熟。     

Decreased perforin and granzyme B expression in senescent HIV-1-specific cytotoxic T lymphocytes

Cytotoxic T lymphocyte (CTL) senescence may be an important mechanism of immune failure in HIV-1 infection. We find that senescence of HIV-1-specific CTL clones causes loss of killing activity, preventable by transduction with telomerase. Furthermore, senescence is associated with reduced expression of the effector molecules granzyme and perforin, suggesting CTL "exhaustion" can result in hypofunction. These results agree with other studies showing that HIV-1-specific CTL exhibit abnormal phenotypes in vivo, and suggest the possibility that chronic turnover is an important mechanism of antiviral failure in HIV-1 infection.     

Human granzyme B is essential for DNA fragmentation of susceptible target cells

We have partially characterized the granules of the human NK cell line, YT-INDY, and assessed granule-mediated lysis and DNA fragmentation of assorted targets. Biochemical studies demonstrated significant quantities of granzyme B (asp-ase) and a heretofore undescribed chymase but no tryptase (i.e., granzyme A or 3) or distinct met-ase. YT-INDY expressed mRNA for granzyme B, perforin and CCPX. The existence of perforin was confirmed by immunoblot. The granules lysed both human and murine NK-sensitive and NK-resistant targets. YTindependent lytic pathway is associated with the granules. In addition, 4-(2-aminoethyl) benzenesulfonylfluoride hydrochloride (AEBSF), an inhibitor that selectively blocked the chymase and 3,4-dichloroisocoumarin (DCI), an inhibitor that inactivated both chymase and asp-ase activities, marginally affected lysis. By gel electrophoresis and ¹²⁵I-labeled deoxyuridine release assay, only murine cells (SP2/0 and YAC-1) underwent DNA fragmentation, and cleavage was completely inhibited by DCI, whereas EGTA, AEBSF and aurintricarboxylic acid (ATA) had no effect. The results, therefore, underscore the central role of granzyme B in granule-mediated DNA fragmentation, emphasize that the protease acts via an ATA-resistant endonuclease pathway and stress that nucleolysis does not invariably accompany granule-mediated cytolysis. Finally, ATA inhibited the asp-ase activity of isolated but not granule-associated granzyme B. ATA, therefore, is not a specific endonuclease inhibitor and results obtained with ATA should be viewed cautiously.     

穿孔素和颗粒酶-生物导弹的理想材料

穿孔素和颗粒酶是细胞毒性细胞两类重要的效应分子,能导致被病原体感染的细胞和肿瘤细胞发生凋亡。随着对疾病靶向性治疗研究的进展,生物导弹的研究也倍受瞩目。根据穿孔素和颗粒酶的生物学特点,有望在生物导弹的应用中占有一席之地,本文就这方面的问题作一综述。     

盐霉素增强吉非替尼诱导人肺腺癌细胞株A549凋亡的作用

目的：探讨盐霉素联合吉非替尼诱导人肺腺癌细胞株A549凋亡的协同作用。方法：采用MTT的方法检测盐霉素对A549细胞生长的抑制作用;流式细胞术检测盐霉素对A549细胞凋亡和线粒体膜电位的影响;比色法检测caspase-3、-8和-9活性;Westernbloting分析细胞色素C、Bcl-2、p-EGFR、p-Akt和p-ERK蛋白水平。结果：盐霉素与吉非替尼单用均出现不同程度的细胞增殖抑制作用和诱导细胞凋亡作用;而盐霉素与吉非替尼联合作用,能更显著地抑制细胞增殖,且凋亡细胞显著增加（P<0.05）。盐霉素单独作用A549细胞,线粒体膜电位显著下降,细胞内活性氧和Ca2+在短期内显著升高,胞浆细胞色素C含量以及caspase-3、-8和-9活性均显著增加,与对照组比较差异均有统计学意义;吉非替尼单用则主要表现为对p-EGFR、p-Akt和p-ERK蛋白表达的抑制作用,而对胞浆细胞色素C含量以及caspase-3、-8和-9活性影响较少。Westernblotting检测发现,联合用药组的Bcl-2、p-EGFR、p-Akt和p-ERK蛋白表达量明显减少,但是对EGFR、Akt和ERK总蛋白水平无显著影响。结论：盐霉素与吉非替尼联用具有较好的协同作用,可能通过Bcl-2途径及线粒体凋亡途径诱导人肺腺癌A549细胞凋亡,提高A549细胞对吉非替尼的敏感性。     

Expression of perforin-granzyme pathway genes in the bursa of infectious bursal disease virus-infected chickens

Infectious bursal disease (IBD) is an economically important immunosuppressive disease of chickens. The IBD virus (IBDV) actively replicates in B cells and causes severe bursal damage. Generally, T cells are refractory to infection with IBDV but are known to promote virus clearance. However, the mechanisms of T cell mediated viral clearance are not well understood. In this study, we evaluated the molecular mechanisms of cytotoxic T cell responses in the pathogenesis of IBD in chickens. Infection of chickens with IBDV was accompanied by the infiltration of CD4⁺ and CD8⁺ T cells in the bursa. There was an upregulation in the gene expression of important cytolytic molecules; perforin (PFN), granzyme-A (Gzm-A), DNA repair and apoptotic proteins; high mobility proteins group (HMG) and poly (ADP-ribose) polymerase (PARP) in the bursa of Fabricius (BF) whereas expression of NK (natural killer) lysin was downregulated. Importantly, PFN producing CD4⁺ and CD8⁺ T cells were also detected in the bursa of IBDV-infected chickens by immunohistochemistry. The Th1 cytokines, IL-2 and IFN-γ expression was also strongly upregulated, suggesting the activation of T cells. The findings of this study highlight the mechanisms of IBD pathogenesis and the role of cytotoxic T cells in the clearance of virus-infected cells.     

Granzyme B and perforin can be used as predictive markers of acute rejection in heart transplantation

We have investigated perforin and granzyme B expression in graft-infiltrating lymphocytes of patients who underwent heart transplantation. Those proteins are commonly present in the cytoplasmic granules of cytotoxic T lymphocytes and are released upon effector-target cell interaction. From 28 patients 103 endomyocardial biopsies were obtained and examined by histology and immunocytochemical analysis using relevant monoclonal antibodies. We found that “high” biopsy histological grades were associated with perforin and granzyme B expression in graft-infiltrating lymphocytes of patients with acute severe rejection crisis. In contrast, these markers were not detected in patients without rejection or during graft stabilization. Interestingly, in patients with mild rejection and “low” histological grades, two groups could be distinguished with a differential expression of the two intracytoplasmic proteins. The presence of perforin and granzyme B-expressing cells was found to be predictive of rapid progression to severe rejection, so that this situation required additional treatment; in contrast, their absence seemed to correlate with a good graft outcome without additional treatment. Moreover, perforin and granzyme B expression seemed to be down-regulated by immunosuppressive drugs, which coincided with graft stabilization. In conclusion, our data suggest that detection of granzyme B and perforin in graft-infiltrating lymphocytes might be helpful for routinely monitoring heart transplant patients.     

Phytoncides (wood essential oils) induce human natural killer cell activity

To explore the effect of forest bathing on the human immune system, we investigated the effect of phytoncides (wood essential oils) on natural killer (NK) activity and the expression of perforin, granzyme A and granulysin in human NK cells. We used NK-92MI cell, an interleukin-2 independent human NK cell line derived from the NK-92 cell, in the present study. NK-92MI cells express the CD56 surface marker, perforin, granzyme A, and granulysin by flow cytometry and are highly cytotoxic to K562 cells in chromium release assay. Phytoncides significantly increase cytolytic activity of NK-92MI cells in a dose-dependent manner and significantly increase the expression of perforin, granzyme A, and granulysin in the NK-92MI cells. Phytoncides also partially, but significantly, restore the decreased human NK activity and the decreased perforin, granzyme A, and granulysin expression in NK-92MI cells induced by dimethyl 2,2-dichlorovinyl phosphate (DDVP), an organophosphorus pesticide. Pretreatment with phytoncides partially prevents DDVP-induced inhibition of NK activity. Taken together, these data indicate that phytoncides significantly enhance human NK activity and this effect is at least partially mediated by induction of intracellular perforin, granzyme A, and granulysin.