DURING ACTIVE VISCEROCUTANEOUS LEISHMANIASIS THE ANTI-P2 HUMORAL RESPONSE IS SPECIFICALLY TRIGGERED BY THE PARASITE P-PROTEINS

In this work we show that in the sera from dogs naturally infected wit h the protozoan parasite Leishmania infantum there are antibodies that react specifically against the parasite acidic ribosomal proteins LiP 2a and LiP2b, and that each one of the Leishmania P proteins elicits a specific humoral immune response. Using synthetic peptides, the antig enic epitope of these proteins has been mapped in a single region loca ted adjacent to the C-terminal domain highly conserved among the eukar yotic P proteins. The anti-P antibodies elicited during the Leishmania infection do not recognize the conserved C-terminal domain of the par asite P proteins, in contrast with the findings reported in Chagas' di sease or systemic lupus erythematosus. The antigenic epitopes of the L iP2a and LiP2b are almost identical in amino acid sequence. No reactiv ity against Trypanosoma cruzi and human P proteins was found in sera f rom L. infantum-infected dogs.