Humoral and cellular immune response to a Microsporum canis recombinant keratinolytic metalloprotease (r-MEP3) in experimentally infected guinea pigs.

In order to better understand the host-fungus relationship in Microsporum canis dermatophytosis and to identify major fungal antigens, the immune response to a crude exoantigen preparation and to a purified recombinant keratinolytic metalloprotease (r-MEP3) was evaluated in guinea pigs experimentally infected with M. canis. Humoral and cellular immune responses were assessed from day 0 to day 57 post-infection (PI), the former by enzyme-linked immunosorbent assay (ELISA) and the latter via a lymphocyte proliferation assay. Infected guinea pigs developed humoral and cellular responses to both M. canis exoantigen and r-MEP3, while no specific immune response to these antigens was observed in control animals. This is the first report on the development of both humoral and cell-mediated immune responses to a purified keratinase in M. canis dermatophytosis.