Characterization of murine B-cell epitopes on the Mycobacterium leprae proline-rich antigen by use of synthetic peptides.

Using synthetic peptides representing overlapping sequences of the 100-amino-acid-long N-terminal region of the proline-rich antigen of Mycobacterium leprae (PRA), we have mapped the epitopes in the primary structure of PRA recognized by four monoclonal antibodies. The M. leprae-specific monoclonal antibody F47-9 recognized the amino acid sequence LGSAYP (residues 34 to 39). Both monoclonal antibodies F67-1 and F67-5 recognized the sequence YPPP within the repeated sequence of PRA at four sites (residues 38 to 41, 50 to 53, 60 to 63, and 70 to 73). Monoclonal antibody F126-5 recognized the sequence SYPPP, also within the repeat, at three sites (residues 49 to 53, 59 to 63, and 69 to 73). All three epitopes appeared to be linear as far as can be determined by this approach.