Antigenic profiling of Leishmania amazonensis microsomal fraction to support vaccine development

Vaccination remains the most promising long-term strategy for controlling leishmaniasis, as individuals who recover from primary infection generally develop protective immunity. However, no vaccine is currently available for human use. In this study, we identified two immunogenic proteins that may account for the protective effect previously observed with the Leishmania amazonensis microsomal fraction (MicF), which confers protection in murine models. Both proteins were expressed in Escherichia coli and used to immunize mice, eliciting specific humoral responses and promoting elevated production of Th1-associated cytokines. Considering the well-documented difficulty in inducing effective immunity against L. amazonensis, a species associated with diffuse cutaneous leishmaniasis and marked host anergy, the identification of these proteins as strong immunogens is noteworthy. Collectively, our findings provide preliminary evidence supporting the Leishmania homolog of receptors for activated C kinase (LACK) and phosphoenolpyruvate carboxykinase (PEPCK) as potential vaccine candidates against L. amazonensis.