Ndarathi C M
Institute of Parasitology, McGill University, Ste-Anne-de-Bellevue, PQ, Canada.
Parasitol Res. 1992;78(4):324-8. doi: 10.1007/BF00937091.
Soluble exoantigens of Trypanosoma lewisi were obtained from short-culture systems of dividing epimastigotes and non-dividing trypomastigotes incubated in phosphate-buffered saline glucose solution (PBSG) for 3 h at 37 degrees C. Suppression of normal rat-spleen cell responses to mitogen concanavalin A (Con A) occurred at high exoantigens concentrations. The epimastigote-derived exoantigens were more suppressive than the trypomastigote-derived exoantigens. The suppression of Con A stimulation was ablated by the addition of exogenous interleukin-2 (IL-2) or washing of spleen cells that had been incubated with suppressing concentrations of the epimastigote exoantigens for 24 h prior to Con A stimulation. These results strongly suggest that exoantigens of T. lewisi play an important immunoregulatory role during the course of infection and that they achieve this by inhibiting the production of IL-2 by T-helper cells.
从在磷酸盐缓冲盐水葡萄糖溶液（PBSG）中于37℃孵育3小时的分裂型上鞭毛体和非分裂型锥鞭毛体的短期培养系统中获得了路氏锥虫的可溶性外抗原。在高浓度外抗原情况下，正常大鼠脾细胞对促有丝分裂原刀豆球蛋白A（Con A）的反应受到抑制。源自上鞭毛体的外抗原比源自锥鞭毛体的外抗原更具抑制性。通过添加外源性白细胞介素-2（IL-2）或洗涤在Con A刺激前已用抑制浓度的上鞭毛体外抗原孵育24小时的脾细胞，Con A刺激的抑制作用被消除。这些结果有力地表明，路氏锥虫的外抗原在感染过程中发挥重要的免疫调节作用，并且它们通过抑制辅助性T细胞产生IL-2来实现这一点。
