Elkhalifa M Y, Ghalib H W, Dafa'Alla T, Williams J F
Department of Microbiology and Public Health, Michigan State University, East Lansing.
Clin Exp Immunol. 1991 Dec;86(3):433-9. doi: 10.1111/j.1365-2249.1991.tb02949.x.
Characterization of in vitro lymphocyte responsiveness was performed on selected groups of onchocerciasis patients from Sudan and Sierra Leone. These patients manifested a very broad range of clinical signs and showed widely divergent parasite infection intensities. Lymphocyte proliferative responses to soluble Onchocerca volvulus antigen (sAg) were poor in infected persons; mitogen and PPD responses were maintained in the normal range in one group of patients from southwestern Sudan, but were profoundly depressed in a group from N.E. Sudan. Proliferative responses and interferon-gamma (INF-gamma) secretion were very significantly depressed in the presence of live microfilariae of O. volvulus or secretions/excretions (S/E) from microfilariae (mf) or from female, but not male, adult parasites. Lymphocyte responses were maintained near normal when exogenous IL-2 was added to these cultures. The results indicate that O. volvulus infection and its clinical consequences are not consistently associated with systemic deficits in immune responsiveness. However, suppression of lymphocyte reactivity by mf and S/E in vitro suggests that direct parasite intervention in host cell responses could be taking place in vivo, perhaps at the local microenvironment level; mediated by effects on cytokine production.
对来自苏丹和塞拉利昂的盘尾丝虫病患者的选定组进行了体外淋巴细胞反应性的表征。这些患者表现出非常广泛的临床症状，并且显示出广泛不同的寄生虫感染强度。感染人群对旋盘尾丝虫可溶性抗原（sAg）的淋巴细胞增殖反应较差；苏丹西南部一组患者的丝裂原和结核菌素纯蛋白衍生物反应维持在正常范围内，但苏丹东北部一组患者的反应则严重受抑。在存在旋盘尾丝虫活微丝蚴或微丝蚴（mf）或雌性而非雄性成虫寄生虫的分泌物/排泄物（S/E）的情况下，增殖反应和干扰素-γ（INF-γ）分泌非常显著地受抑。当向这些培养物中添加外源性白细胞介素-2时，淋巴细胞反应维持在接近正常的水平。结果表明，旋盘尾丝虫感染及其临床后果与免疫反应性的全身性缺陷并非始终相关。然而，体外微丝蚴和S/E对淋巴细胞反应性的抑制表明，寄生虫可能在体内，也许在局部微环境水平直接干预宿主细胞反应；这是由对细胞因子产生的影响介导的。
