Umekita L F, Barbaro K C, Mota I
Laboratório de Immunopatologia, Instituto Butantan, São Paulo, Brasil.
Braz J Med Biol Res. 1996 Jan;29(1):25-31.
Two strains of Trypanosoma cruzi (Y and CL) were used to study the specificity and role of anti-T. cruzi clearance antibodies. Clearance antibodies were only induced after immunization with living blood-stream trypomastigotes (Btrys) but not with dead parasites. Btrys of either strain were readily cleared from the circulation after passive immunization with anti-Y or anti-CL serum provided that the homologous strain was used. CL or Y Btrys sensitized in vitro with the homologous or heterologous antiserum and transferred to normal mice were cleared from the circulation only when the homologous antiserum was used. Clearance antibodies were removed from serum by absorption with the homologous but not with the heterologous strain. Clearance antibodies were removed from serum by absorption with living Btrys but not with fixed parasites. These results suggest that: a) the parasite epitopes involved in the clearance are peculiar to each strain, b) the clearance antibodies are specific to these epitopes, and c) a proper conformation of the parasite antigens is required for the induction and effector activity of the clearance antibodies.
使用两株克氏锥虫（Y株和CL株）来研究抗克氏锥虫清除抗体的特异性和作用。清除抗体仅在用活的血流型锥鞭毛体（Btrys）免疫后诱导产生，而用死寄生虫免疫则不会诱导产生。如果使用同源株，用抗Y或抗CL血清进行被动免疫后，两种株系的Btrys都能迅速从循环中清除。体外经同源或异源抗血清致敏并转移到正常小鼠体内的CL或Y Btrys，只有在使用同源抗血清时才会从循环中清除。通过用同源株而非异源株吸收血清可去除清除抗体。通过用活的Btrys而非固定寄生虫吸收血清可去除清除抗体。这些结果表明：a）参与清除的寄生虫表位对每个株系而言是独特的，b）清除抗体对这些表位具有特异性，c）清除抗体的诱导和效应活性需要寄生虫抗原具有适当的构象
