The antigenicity of synthetic peptide fragments of lactate dehydrogenase C4

Lactate dehydrogenase C4 (LDH-C4) is an antigenic protein found only in spermatozoa and the mature testis. Synthetic peptides containing the amino acid sequences of the C-subunit, designated MC5-15, MC97-110 and MC211-220, were each conjugated to the carrier proteins diphtheria toxoid or bovine serum albumin. Rabbits immunized with these peptide-carrier conjugates produced antibodies to the peptide that cross-reacted with native LDH-C4. These data support our map that identifies antigenic domains of LDH-C4. Such synthetic peptides will be useful in the design of a contraceptive vaccine.