Partial purification, immunogenicity and putative new localization of a native Leishmania heat shock protein 70

in this work we focused on a recombinant protein, containing approximately 230 aminoacids from the carboxy-terminal extremity of the leishmania chagasi heat shock protein 70. the heat shock proteins are among the most abundant parasite antigens and conserved proteins in nature, and this family is one of the most immunogenic proteins present within pathogenic organisms. the recombinant protein has been partially purified by electroelution and further precipitation in acetone. the electroelution process did not modify its immunological and antigenic properties, as it continued to be recognized by visceral leishmaniasis positive sera and by the immunological system of rabbits during the immunization, both in elisa and western blots. the production of polyclonal sera with an antigen concentration that is far from the maximum dose, strengthens the idea that the proteins of this family are highly antigenic and immunogenic. our results with these polyclonal sera in the direct agglutination assay allow the conclusion that the leishmania chagasi native heat shock protein 70 is distributed on the surface of the parasite.