Begara I, Luján L, Collie D S, Miller H R, Watt N J
Department of Veterinary Clinical Studies, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Midlothian, UK.
Vet Immunol Immunopathol. 1995 Nov;49(1-2):75-88. doi: 10.1016/0165-2427(95)05450-k.
To investigate the effects of maedi-visna virus (MVV) infection on cell-mediated immunity, the in vitro response of bronchoalveolar lavage fluid (BALF) and peripheral blood (BP) lymphocytes (PBL) to exogenous mitogen was analysed. BALF and PBL from control (n = 9) and MVV-infected (n = 7) animals were cultured fro 3 days in the presence and absence of concanavalin A (Con A). Lymphocyte expression of the interleukin-2 receptor (IL-2R) antigen, a parameter of lymphocyte activation, was quantified by dual-colour flow cytometry using the bovine anti-IL-2R monoclonal antibody IL-A111. IL-2R expression by lymphocytes in BALF and PB from control and MVV-infected animals, with and without Con A stimulation, were compared. In the absence of Con A stimulation, the proportion of cultured BALF CD8+ and gamma delta T cells expressing IL-2R was significantly (P < 0.05) lower for MVV-infected animals than for controls. After Con A stimulation the proportion of BALF CD4+ lymphocytes from MVV-infected animals that expressed IL-2R remained significantly (P < 0.05) lower than for controls. Comparisons within group showed that, after Con A stimulation, the proportion of all the T cell subsets in the control group expressing IL-2R, namely CD4+ (P < 0.001), CD8+ (P < 0.001) and gamma delta T cells (P < 0.05), was significantly increased. In the MVV-infected group, this increase was significant (P < 0.05) for CD4+ and CD8+ T cells, but not for gamma delta T cells. In vitro mitogen stimulation of PB T lymphocytes from both control and MVV-infected animals induced a significant elevation in the proportion of all T cell subsets expressing IL-2R when compared to cultured unstimulated control cells. However, there was considerable heterogeneity in the response to Con A of PB T cells from both groups of animals. The expression of IL-2R followed a different pattern to that of BALF lymphocytes, the proportion of unstimulated gamma delta / IL-2R+ T cells from MVV-infected animals being significantly (P < 0.05) higher than that of controls, and the proportion of cultured unstimulated CD8+ / IL-2R+ T cells from MVV-infected animals being significantly (P < 0.05) lower than that from controls. From these studies it can be concluded that the BALF T lymphocyte immune dysfunction observed during natural MVV infection, characterized by impaired IL-2R expression, is maintained under in vitro conditions.
为研究梅迪-维斯纳病毒（MVV）感染对细胞介导免疫的影响，分析了支气管肺泡灌洗液（BALF）和外周血（BP）淋巴细胞（PBL）对外源有丝分裂原的体外反应。将来自对照动物（n = 9）和MVV感染动物（n = 7）的BALF和PBL在有和无刀豆球蛋白A（Con A）存在的情况下培养3天。使用牛抗IL-2R单克隆抗体IL-A111通过双色流式细胞术对淋巴细胞活化参数白细胞介素-2受体（IL-2R）抗原的表达进行定量。比较了来自对照和MVV感染动物的BALF和PB中淋巴细胞在有和无Con A刺激下的IL-2R表达。在无Con A刺激的情况下，MVV感染动物培养的BALF中表达IL-2R的CD8 +和γδT细胞比例显著低于对照动物（P <0.05）。Con A刺激后，MVV感染动物的BALF中表达IL-2R的CD4 +淋巴细胞比例仍显著低于对照动物（P <0.05）。组内比较显示，Con A刺激后，对照组中所有表达IL-2R的T细胞亚群比例，即CD4 +（P <0.001）、CD8 +（P <0.001）和γδT细胞（P <0.05）均显著增加。在MVV感染组中，CD4 +和CD8 + T细胞的这种增加显著（P <0.05），但γδT细胞未增加。与未刺激的对照细胞培养物相比，对来自对照和MVV感染动物的PB T淋巴细胞进行体外有丝分裂原刺激均导致所有表达IL-2R的T细胞亚群比例显著升高。然而，两组动物的PB T细胞对Con A的反应存在相当大的异质性。IL-2R的表达模式与BALF淋巴细胞不同，MVV感染动物未刺激的γδ/ IL-2R + T细胞比例显著高于对照动物（P <0.05），MVV感染动物培养的未刺激的CD8 + / IL-2R + T细胞比例显著低于对照动物（P <0.05）。从这些研究可以得出结论，在自然MVV感染期间观察到的以IL-2R表达受损为特征的BALF T淋巴细胞免疫功能障碍在体外条件下得以维持。
