Analysis of the anti-Schistosoma mansoni surface antibody response during murine infection and its potential contribution to protective immunity.
Analysis of the anti-Schistosoma mansoni surface antibody response during murine infection and its potential contribution to protective immunity.
复制标题
分析小鼠感染期间抗曼氏血吸虫表面抗体反应及其对保护性免疫的潜在贡献。
作者：
P. Omer Ali;S. Smithers;Q. Bickle;S. Phillips;D. Harn;A. Simpson
从慢性感染小鼠的血清与匀质化的精子卵的吸收减少了94%的抗体结合到精子体表面，表明几乎所有的精子体表面识别在慢性感染是由于与卵共享的表位。用蛋白质抗原已通过煮沸和用蛋白酶K消化而去除的蛋匀浆吸收血清导致抗表面抗体的类似减少，这表明所有被识别的共有表位本质上是碳水化合物。分析抗碳水化合物抗体产生的时间进程和感染单一性别的寄生虫的小鼠的抗体水平表明，鸡蛋直接刺激了这种反应。小鼠单克隆抗体被鉴定为以非常高的水平结合到精子囊泡表面，并且识别与卵子共享的碳水化合物表位。其中三种之前已被证明可以被动转移抗性，这表明这些表面碳水化合物是小鼠保护性免疫的潜在靶点。所有抗碳水化合物单抗也与其它哺乳动物的囊胚表面结合。因此，在慢性感染中针对这些表位的强烈免疫应答可以解释观察到的交叉特异性免疫。接种辐照尾蚴的小鼠缺乏高水平的抗碳水化合物抗体，它们对表面的识别主要是由于针对种属特异性多肽表位的抗体。对于Mr大于200，000和38，000的抗原，证明了这些表位存在于携带被来自慢性感染小鼠的抗体识别的碳水化合物部分的相同抗原上。这种特异性多肽识别也反映在暴露于辐照尾蚴产生的免疫力中。
Absorption of serum from chronically infected mice with homogenized schistosome eggs reduced antibody binding to the schistosomulum surface by 94%, indicating that almost all schistosomulum surface recognition during chronic infection is due to epitopes shared with the egg. Absorption of the serum with egg homogenate from which protein antigens had been removed by boiling and digestion with proteinase K resulted in a similar reduction of antisurface antibody demonstrating that all the shared epitopes that are recognized are carbohydrate in nature. Analysis of the time course of anticarbohydrate antibody production and the levels of antibody in mice infected with a single sex of schistosome indicated that eggs directly stimulated this response. Mouse mAb were identified that bound at very high levels to the schistosomulum surface and that recognized carbohydrate epitopes shared with the egg. Three of these had previously been demonstrated to passively transfer resistance, indicating that these surface carbohydrates are potential targets of protective immunity in the mouse. All the anticarbohydrate mAb also bound to the surface of schistosomula of other schistosome species. Thus, the strong immune response against these epitopes in chronic infection could account for the cross-specific immunity observed. Mice vaccinated with irradiated cercariae lacked high levels of anticarbohydrate antibodies and their recognition of the surface was largely due to antibody to species-specific polypeptide epitopes. With respect to the Mr greater than 200,000 and 38,000 antigens, it was demonstrated that these epitopes were present on the same antigens that bear the carbohydrate moieties recognized by antibodies from chronically infected mice. This specific polypeptide recognition is also reflected in the immunity generated by exposure to irradiated cercariae.