Studies on immunosuppression indued by Measles Virus

用麻疹病毒（MV）感染外周血单个核细胞（PBMC）和T淋巴细胞，用蛋白激酶C （PKC）激活剂12-肉豆蔻酸13-醋酸酯（PMA）和钙离子载体离子霉素进行培养。刺激后，与模拟感染细胞相比，mv感染细胞的细胞活力和BrdU的掺入降低。DNA含量分析和末端脱氧转移酶（TdT）介导的dUTP缺口末端标记表明，PMA +离子霉素激活的mv感染T淋巴细胞的次二倍体部分和DNA片段化增加。这些数据表明，MV可诱导PMA +离子霉素激活的细胞凋亡。与PMA +离子霉素刺激相比，植物血凝素（PHA）刺激有丝分裂不会诱导mv感染细胞的凋亡细胞死亡，尽管细胞增殖受到抑制。刺激诱导细胞凋亡。病毒感染细胞可能是免疫抑制的一种机制。我们研究了麻疹病毒（MV）诱导不同淋巴细胞群细胞内细胞因子水平的变化。在莫能菌素存在的条件下，用2-肉豆酸13-乙酸佛波酯（phorbol 2-myristate 13-acetate， PMA）加离子霉素培养mv感染和未感染的外周血单个核细胞10小时。同时染色表面抗原和细胞内细胞因子，白细胞介素(IL)-2、干扰素(IFN)- γ、IL-4，流式细胞术分析。与未感染的淋巴细胞相比，mv感染的CD3+、CD4+、CD8+淋巴细胞中表达IL-2和ifn - γ的细胞百分比显著增加。IL-2主要在病毒感染的CD4+淋巴细胞中升高，ifn - γ主要在病毒感染的CD8+淋巴细胞和γ - T淋巴细胞中升高。IL-4的表达不受MV感染的影响。这些结果表明，在麻疹急性期，MV提高了1型细胞因子的细胞内水平。

Peripheral blood mononuclear cells (PBMC) and T lymphocytes were infected with measles virus (MV) and cultured with a protein kinase C (PKC) activator, phorbol 12-myristate 13-acetate (PMA) and a calcium ionophore, ionomycin. After stimulation, cell viability and incorporation of BrdU were decreased in MV-infected cells compared to mock-infected cells. DNA content analysis and terminal deoxytransferase (TdT)-mediated dUTP nick end labeling demonstrated that the hypodiploid fraction and DNA fragmentation were increased in MV-infected, T lymphocytes activated with PMA plus ionomycin. These data suggest that MV induces apoptotic cell death in cells activated by PMA plus ionomycin. In contrast to stimulation with PMA plus ionomycin, mitogenic stimulation with phytohaemagglutinin (PHA) did not induce apoptotic cell death in MV-infected cells, although cell proliferation was suppressed. Apoptosis induced in stimulated. MV-infected cells may be one mechanism of immunosuppression.We investigated the changes in intracellular cytokine levels in different lymphocyte populations induced by measles virus (MV). MV-infected and uninfected peripheral blood mononuclear cells were cultured with phorbol 2-myristate 13-acetate (PMA) plus ionomycin in the presence of monensin for 10h. Surface antigen and intracellular cytokines, interleukin (IL)-2, interferon (IFN)-gamma, and IL-4, were stained simultaneously and analyzed by flow cytometry. The percentage of cells that expressed IL-2 and IFN-gamma was significantly increased in MV-infected CD3+, CD4+, CD8+ lymphocytes as compared with uninfected lymphocytes. IL-2 was increased mainly in MV-infected CD4+ lymphocytes, whereas IFN-gamma was increased mainly in MV-infected CD8+ lymphocytes and gammadelta T lymphocytes. Expression of IL-4 was unaffected by MV infection. These results demonstrate that MV enhances the intracellular levels of type 1 cytokines during the acute phase of measles.