The effect of staphylococcal enterotoxins on the primary in vitro immune response.
The effect of staphylococcal enterotoxins on the primary in vitro immune response.
复制标题
葡萄球菌肠毒素对初级体外免疫反应的影响。
作者：
Bennett G. Smith;H. Johnson
葡萄球菌肠毒素，像几种植物凝集素，已被证明刺激有丝分裂活性和淋巴细胞产生淋巴因子。本文观察了肠毒素A和B对小鼠（C57 BL/6）脾细胞对绵羊红细胞（SRBC）的体外原代空斑形成细胞（PFC）反应的影响。当在SRBC添加时或24小时前将毒素添加到培养物中时，0.1 μ g肠毒素A和3- 6 μ g肠毒素B对4或5天培养物中的PFC反应的抑制大于90%。肠毒素A和B均为T淋巴细胞有丝分裂原。动力学数据表明，肠毒素（10杯）抑制PFC反应早在第3天，但在第4天和第5天相对更具抑制性。PFC反应被抑制时，肠毒素添加到文化在同一时间作为抗原或一天后，它被增强时，在第2天添加，它不受影响时，在第3天添加的4天的文化。此外，肠毒素A的存在下，在第一个24小时的文化和随后的去除仍然是有效的抑制PFC反应时，它是目前在整个文化时期。因此，肠毒素的PFC抑制特性似乎影响体外免疫应答中的一些早期事件。α-甲基-D-吡喃甘露糖苷可阻断刀豆球蛋白A（conA）对PFC的抑制作用，但对肠毒素A无影响。因此，这两种有丝分裂原似乎与淋巴细胞上不同的受体发生反应，或者它们的反应动力学不同。葡萄球菌肠毒素对脾细胞PFC反应的影响与凝集素如con A的报道非常相似。肠毒素的结构比con A简单，因此在研究淋巴细胞的各种生物活性方面非常有用。
Staphylococcal enterotoxins, like several plant lectins, have been shown to stimulate mitogenic activity and lymphokine production in lymphocytes. The effect of enterotoxins A and B on the primary in vitro plaque-forming cell (PFC) response of mouse (C57BL/6) spleen cells to sheep red blood cells (SRBC) was examined. PFC responses in 4- or 5-day cultures were inhibited greater than 90% by 0.1 mug enterotoxin A and by 3- to 6-mug enterotoxin B when the toxins were added to the cultures either at the time of SRBC addition or 24 hr before. Both enterotoxins A and B were shown to be T lymphocyte mitogens. Kinetic data indicated that the enterotoxins (10 mug) inhibited the PFC response as early as day 3, but were relatively more inhibitory at days 4 and 5. The PFC response was inhibited when enterotoxins were added to cultures at the same time as antigen or a day later; it was enhanced when added at day 2; and it was unaffected when added at day 3 of 4-day cultures. Further, the presence of enterotoxin A during the first 24 hr of culture and subsequent removal was still as effective in inhibiting the PFC response as when it was present throughout the culture period. The PFC inhibitory properties of enterotoxins appear, then, to affect some early event(s) in the in vitro immune response. Alpha-methyl-D-mannopyranoside blocked the PFC inhibitory effect of concanavalin A (con A), but it had no effect on enterotoxin A. The two mitogens appear, then, to react with different receptors on the lymphocytes or to differ in the dynamics of their reactivity. The effects of staphylococcal enterotoxins on the PFC response of spleen cells were remarkably similar to those reported for lectins such as con A. Enterotoxins are structurally simpler than con A and should therefore be quite useful in studying various biologic activities of lymphocytes.