Analysis of the antigenic properties of the L. infantum Hsp70: design of synthetic peptides for specific serodiagnosis of human leishmaniasis.

The 70-kDa heat shock protein (Hsp70) is a major target of the humoral immune response during Leishmania infections. In the present paper, it is shown that 84.6% of sera from mucocutaneous leishmaniasis (MCL) patients and 78.9% of sera from visceral leishmaniasis (VL) patients reacted with the L. infantum Hsp70. The mapping of the antigenic determinants indicated that this protein is highly rich in linear B-epitopes. As the complete protein cannot be used for specific serodiagnosis of VL because it is also recognized by the sera from Chagas' disease patients, a search for specific epitopes recognized by leishmaniasis patients was undertaken. A 50-mer synthetic peptide, located in the most divergent region of the protein, was found to be recognized by a high percentage of leishmaniasis sera and not recognized by chagasic sera. Such a tool would be particularly useful for serodiagnosis of leishmaniasis in geographical areas where mixed infections with Trypanosoma cruzi and Leishmania occurs.