Schofield L
Department of Medical and Molecular Parasitology, New York University School of Medicine, NY 10010.
Bull World Health Organ. 1990;68 Suppl(Suppl):66-73.
Sporozoites of malaria are covered with a repetitive surface antigen, the circumsporozoite (CS) protein. This antigen also appears to be a major target of the host immune response. The natural immunogenicity of the CS protein has led to attempts to develop the molecule as a vaccine candidate. It seems paradoxical, however, that a successful parasite should present to the host an immunogenic surface molecule which would induce protective immunity. In this paper we suggest that the CS protein is not the target of protective immunity under natural conditions, and that naturally immunogenic repetitive antigens in malaria and other parasites have evolved as a mechanism of immune evasion, via the induction of thymus-independent B-cell responses.
疟原虫的子孢子表面覆盖着一种重复的表面抗原，即环子孢子（CS）蛋白。这种抗原似乎也是宿主免疫反应的主要靶点。CS蛋白的天然免疫原性促使人们尝试将该分子开发为候选疫苗。然而，看似矛盾的是，一种成功的寄生虫竟然会向宿主呈现一种能诱导保护性免疫的免疫原性表面分子。在本文中，我们认为CS蛋白在自然条件下并非保护性免疫的靶点，而且疟疾及其他寄生虫中天然具有免疫原性的重复抗原是作为一种免疫逃避机制进化而来的，其方式是诱导非胸腺依赖性B细胞反应。
