Shoker A S, Yang H, Murabit M A, Jamil H, al-Ghoul A, Okasha K
Division of Nephrology, College of Medicine, University of Saskatchewan Saskatoon, Canada.
Mol Cell Biochem. 1997 Jun;171(1-2):75-83. doi: 10.1023/a:1006815430622.
We investigated the role of endogenous or exogenous nitric oxide (NO) on human lymphocyte function. We used sodium nitroprusside, nitroglycerine, S-nitroso-N-acetylpenicillamine, sodium nitrite and S-nitroso-L-glutathione as NO-generating compounds. All agents were used at doses that do not produce direct cytotoxicity as measured by trypan blue exclusion as well as chromium-51 release assay. The immune responses examined were peripheral blood lymphocytes (PBL) proliferation and IL-2 production after activation with OKT3 and PHA; allogeneic mediated proliferation and cell mediated cytotoxicity (CML) in MLR; IgG and IgM production after PBL activation with Con-A; proliferation and expression of IFN-gamma and IL-4 mRNA after activation of allogeneic CD4+T cell clones. Cytokine mRNA expression was measured by reverse transcriptase PCR. Our results show that proliferating lymphocytes do not produce a detectable amount of NO as measured by the Griess reaction. In separate experiments, the addition of NG-monomethyl-L-arginine (L-NMMA) did not affect lymphocyte proliferation. Sodium nitroprusside and nitroglycerine exerted a dose dependent antimitogenic effect, inhibited cytokine production and expression, CML generation and antibody production. DNA gel electrophoresis showed no evidence for enhanced programmed cell death. The antimitogenic effect could not be blocked by the NO scavengers, hemoglobin or methylene blue. In contrast, the other nitric oxide generating compounds did not inhibit lymphocyte mitogenesis. The results suggest that human lymphocytes do not produce appreciable amounts of NO to affect lymphocyte mitogenesis. Sodium nitroprusside and nitroglycerine have a potent but nonspecific immunoinhibitory effect on human lymphocyte function by a mechanism other than NO production. In addition, pharmacological levels of NO do not inhibit human lymphocyte mitogenesis.
我们研究了内源性或外源性一氧化氮（NO）对人淋巴细胞功能的作用。我们使用硝普钠、硝酸甘油、S-亚硝基-N-乙酰青霉胺、亚硝酸钠和S-亚硝基-L-谷胱甘肽作为NO生成化合物。所有试剂的使用剂量均不会产生锥虫蓝排斥试验以及铬-51释放试验所测定的直接细胞毒性。所检测的免疫反应包括用OKT3和PHA激活后外周血淋巴细胞（PBL）增殖和IL-2产生；混合淋巴细胞反应（MLR）中同种异体介导的增殖和细胞介导的细胞毒性（CML）；用Con-A激活PBL后IgG和IgM产生；同种异体CD4 + T细胞克隆激活后IFN-γ和IL-4 mRNA的增殖和表达。通过逆转录酶PCR测定细胞因子mRNA表达。我们的结果表明，通过格里斯反应测定，增殖的淋巴细胞不会产生可检测量的NO。在单独的实验中，添加NG-单甲基-L-精氨酸（L-NMMA）不影响淋巴细胞增殖。硝普钠和硝酸甘油发挥剂量依赖性抗有丝分裂作用，抑制细胞因子产生和表达、CML生成及抗体产生。DNA凝胶电泳未显示程序性细胞死亡增强的证据。抗有丝分裂作用不能被NO清除剂、血红蛋白或亚甲蓝阻断。相反，其他NO生成化合物不抑制淋巴细胞有丝分裂。结果表明，人淋巴细胞不会产生可观量的NO来影响淋巴细胞有丝分裂。硝普钠和硝酸甘油通过产生NO以外的机制对人淋巴细胞功能具有强大但非特异性的免疫抑制作用。此外，药理学水平的NO不抑制人淋巴细胞有丝分裂。
