Laurenti M D, Orn A, Sinhorini I L, Corbett C E P
Laboratório de Patologia de Doenças Infecciosas, LIM-50, Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil.
Braz J Med Biol Res. 2004 Mar;37(3):427-34. doi: 10.1590/s0100-879x2004000300021. Epub 2004 Mar 3.
Complement-depleted and -non-depleted BALB/c mice were inoculated with Leishmania (Leishmania) amazonensis promastigotes into the hind footpad to study the role of the complement system in cutaneous leishmaniasis. Total serum complement activity was measured by hemolytic assay and C3 fragment deposit at the inoculation site was determined by direct immunofluorescence in the early period of infection, i.e., at 3, 24, 48 h and 7 days post-infection. The inflammatory reaction and the parasite burden were evaluated in the skin lesion at 7 and 30 days post-infection. Total serum complement activity decreased in the early phase of infection, from 3 to 24 h, in non-depleted mice compared to non-infected and non-depleted mice. C3 fragment deposit at the site of parasite inoculation was present throughout the period of infection in non-depleted mice. In contrast, no C3 fragment deposit was observed at the inoculation site in complement-depleted mice. Complement-depleted mice showed a significant decrease in the inflammatory response and a significant increase in the number of parasites (70.0 +/- 5.3 vs 5.3 +/- 1.5) at 7 days of infection (P<0.05). A higher number of parasites were also present at 30 days of infection at the inoculation site of complement-depleted mice (78.5 +/- 24.9 vs 6.3 +/- 5.7). These experiments indicate that complement has an important role at the beginning of experimental cutaneous leishmaniasis caused by L. (L.) amazonensis by controlling the number of parasites in the lesion.
将补体缺失和未缺失的BALB/c小鼠的后足垫接种亚马逊利什曼原虫前鞭毛体，以研究补体系统在皮肤利什曼病中的作用。通过溶血试验测量总血清补体活性，并在感染早期，即感染后3、24、48小时和7天，通过直接免疫荧光法测定接种部位的C3片段沉积。在感染后7天和30天评估皮肤病变中的炎症反应和寄生虫负荷。与未感染且补体未缺失的小鼠相比，未缺失补体的小鼠在感染早期（3至24小时）总血清补体活性下降。在未缺失补体的小鼠整个感染期间，寄生虫接种部位均有C3片段沉积。相比之下，在补体缺失的小鼠接种部位未观察到C3片段沉积。在感染7天时，补体缺失的小鼠炎症反应显著降低，寄生虫数量显著增加（70.0±5.3对5.3±1.5）（P<0.05）。在感染30天时，补体缺失的小鼠接种部位也存在更多的寄生虫（78.5±24.9对6.3±5.7）。这些实验表明，补体在由亚马逊利什曼原虫引起的实验性皮肤利什曼病初期通过控制病变中的寄生虫数量发挥重要作用。
