Pompeu M, Freitas A L, dosReis G A, Barral-Netto M
Faculdade de Medicina da Universidade Federal da Bahia, Salvador, Brazil.
Parasitol Res. 1992;78(1):16-22. doi: 10.1007/BF00936175.
Highly susceptible naive BALB/c mice or mice that had previously been immunized i.v. with solubilized homologous antigen (partially resistant) were infected with Leishmania amazonensis. Histologically, the main differences between the two groups were lymphocytic infiltration and macrophage activation. Assays of T-cell function at 3 and 10 weeks after infection revealed that purified T-cells did not proliferate following treatment with leishmania antigen. A mitogenic anti-CD3 monoclonal antibody (mAb) failed to activate T-cells after 3 weeks of infection as judged by proliferation and IL-2 secretion assays. After 10 weeks of infection, anti-CD3 mAb fully activated T-cells to proliferation and IL-2 secretion. On the other hand, T-cells released IL-3 in response to leishmania antigen, anti-CD3 mAb and anti-Thy1 mAb at 3 and 10 weeks post-infection. Surprisingly, a mitogenic anti-Thy 1 mAb (G7) fully activated T-cells even at 3 weeks of infection as judged by proliferative and IL-2 secretion assays. No significant differences were found in the proliferative or interleukin secretory responses of T-cells from animals that had been infected in either the presence or the absence of prior immunization. Since the Thy1 triggering pathway has different accessory cell and cytokine requirements than does the CD3: TCR lymphocyte activation pathway, it is possible that immunization was more effective in changing the cellular interactions of the T-lymphocyte than in altering its intrinsic capabilities.
将高度易感的未免疫BALB/c小鼠或先前经静脉注射可溶性同源抗原免疫（部分抗性）的小鼠感染亚马逊利什曼原虫。组织学上，两组之间的主要差异在于淋巴细胞浸润和巨噬细胞活化。感染后3周和10周的T细胞功能检测显示，用利什曼原虫抗原处理后，纯化的T细胞不增殖。通过增殖和IL-2分泌检测判断，感染3周后，促有丝分裂的抗CD3单克隆抗体（mAb）未能激活T细胞。感染10周后，抗CD3 mAb能完全激活T细胞增殖并分泌IL-2。另一方面，感染后3周和10周，T细胞对利什曼原虫抗原、抗CD3 mAb和抗Thy1 mAb反应释放IL-3。令人惊讶的是，通过增殖和IL-2分泌检测判断，即使在感染3周时，促有丝分裂的抗Thy 1 mAb（G7）也能完全激活T细胞。在有或无预先免疫的情况下感染的动物的T细胞增殖或白细胞介素分泌反应中未发现显著差异。由于Thy1触发途径与CD3:TCR淋巴细胞激活途径相比具有不同的辅助细胞和细胞因子需求，因此免疫在改变T淋巴细胞的细胞相互作用方面可能比改变其内在能力更有效。
