Abstract:
In this study, we compare and contrast various parameters of infection between Balb/c and C57BL/6 mice inoculated with Leishmania major. The Balb/c are susceptible to Leishmania major and eventually die from this infection. The C57BU6 mice are resistant to serious disease, but do become briefly infected. We measured the progress of infection by examining spleen weight, lymph node weight, presence of L. major in the spleen, and the percentage of la positive macrophages in the peritoneal exudate at various times after infection in both strains of mice. From these experiments, we hope to better understand the parameters comprising an effective immune response against L. major, particularly the role of macrophage activation in both mouse strains. In previous experiments in our lab it has been determined that following infection, the Balb/c mice develop lymphoadenopathy, increased foot pad size with the eventual lose of the foot, metastasis of L. major to the spleen, and increased level of positive la peritoneal exudates.In other experiments it has been shown that increased levels of la expression is related to an active immune response to certain intra-cellular parasites and autoimmune processes in genetically abnormal mice. For instance, Beller, Kiely, and Unanue demonstrated that A/St mice showed an increased number, from 7.1% to 69%, of la positive peritoneal macrophages when infected with Listeria monocytogenes. They also demonstrated that this increase in la was only induced when antigen specific T-cells were involved. (1) One way that T-cells are thought to induce la on the surface of macrophages is through the secretion of gamma interferon. (6)
