The Candida albicans
heat shock protein 90 kDa (hsp90-CA) is an important target for protective
antibodies in disseminated
candidiasis of experimental mice and humans. Hsp90-CA is present in the cell wall of Candida pseudohyphae or hyphae--typical pathogenic morphotypes in both mucosal and
systemic Candida infections. However, the potential protective effects of hsp90-CA-specific
antibodies in vaginal
candidiasis has not yet been reported. In the present study we used various
vaccine formulations (recombinant hsp90-CA
protein and hsp90-CA-encoding
DNA vaccine) and routes of administration (intradermal, intranasal, and intravenous) to induce both hsp90-CA-specific systemic and vaginal mucosa immune responses in experimental BALB/c mice. The results showed that intradermal recombinant hsp90-CA
protein priming, followed by intranasal or intradermal recombinant hsp90-CA
protein boosting induced significant increases in both serum and vaginal hsp90-CA-specific
IgG and
IgA antibodies compared to the control group, as well as enhanced hsp90-CA-specific splenocyte responses in vitro. In the intradermally boosted group, subsequent experimental vaginal
Candida infection induced additional increases in the hsp90-CA specific
IgG isotype, suggesting that Candida has the ability to induce a local hsp90-specific
antibody (IgG) response during
vulvovaginal candidiasis. Further work is required to elucidate the importance of immunity to highly conserved
antigens during
infection of the human female reproductive tract where a balance between immunity to and tolerance for commonly
antigens such as hsp90 is necessary for the maintenance of fertility.