Identification and characterization of human B-cell epitopes in recombinant antigens of Leishmania aethiopica

Recombinant DNA fragments from Leishmania aethiopica that code for epitopes which react with human antibodies have been characterized by cross-hybridization studies and DNA sequence analysis. Twenty clones could be grouped into seven different groups (I-VII), probably representing seven different L. aethiopica antigens. The DNA sequences of representative clones from the seven groups have been obtained and the amino acid sequence of the respective recombinant antigens established. The recombinant antigens have been analysed by epitope scanning with patient sera, and octapeptides that contain potential B-cell epitopes have been identified in all seven recombinant antigens. These octapeptides have further been tested with additional patient sera and control sera, and three octapeptides (HAFCHEEG, YHSSVVHD and SYAPCSLK) were found to contain major epitopes recognizing specific antibodies in nine, seven and four, respectively, of the twenty sera tested. Fifteen of the twenty sera reacted with one or more of these three octapeptides