Yamamoto H, Hattori M, Ohashi K, Sugimoto C, Onuma M
Department of epizootiology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
Vet Immunol Immunopathol. 1996 Jan;49(4):375-86. doi: 10.1016/0165-2427(95)05469-3.
The function of CD4+ T cells in antibody production was examined by using T cell subset-depleted chickens. CD4- and CD8-depleted chickens, established by the combination of thymectomy and injection of T cell subset-specific monoclonal antibodies, were immunized with sheep red blood cells (SRBC). Titers of anti-SRBC antibody produced in CD4-depleted chickens were lower than those in control chickens, while no difference in the antibody production was observed between CD8-depleted and control chickens. In chickens depleted of both CD4+ and CD8+ T cells, the recovery of T cells in the periphery was demonstrated starting 3 weeks after T cell depletion. Those T cells recovered in the periphery predominantly expressed CD4 molecules. Although low titers of antibody against SRBC were detected in chickens depleted of both CD4+ and CD8+ T cells, an increase of anti-SRBC antibody production was coincidentally observed with the recovery of CD4+ T cells in the periphery. These results suggest that CD4+ T cells could differentiate in extrathymic environments in chickens, and have a helper function in antibody production similar to that of intrathymic T cells. These extrathymic T cells, however, showed a lower proliferative response to concanavalin A than intrathymic T cells, suggesting that these extrathymic T cells may have some properties distinct from intrathymic T cells.
通过使用T细胞亚群缺失的鸡来研究CD4+ T细胞在抗体产生中的功能。通过胸腺切除和注射T细胞亚群特异性单克隆抗体相结合建立的CD4和CD8缺失的鸡，用绵羊红细胞（SRBC）进行免疫。CD4缺失的鸡产生的抗SRBC抗体滴度低于对照鸡，而CD8缺失的鸡和对照鸡在抗体产生方面未观察到差异。在CD4+和CD8+ T细胞均缺失的鸡中，T细胞耗竭3周后在外周血中出现了T细胞的恢复。在外周血中恢复的那些T细胞主要表达CD4分子。虽然在CD4+和CD8+ T细胞均缺失的鸡中检测到低滴度的抗SRBC抗体，但在外周血中随着CD4+ T细胞的恢复，抗SRBC抗体产生同时增加。这些结果表明，CD4+ T细胞可以在鸡的胸腺外环境中分化，并且在抗体产生中具有与胸腺内T细胞类似的辅助功能。然而，这些胸腺外T细胞对刀豆蛋白A的增殖反应低于胸腺内T细胞，表明这些胸腺外T细胞可能具有一些与胸腺内T细胞不同的特性。
