Vaccines Against Fungal Infections

Abstract

The state-of-the-art reached in developing protective immunity against fungal infections through vaccination makes a survey of methodologies and results timely. This review describes experimental vaccinations against dermatophytes, pathogenic yeasts, and dimorphic fungi with special attention to the anti-Coccidioides immitis vaccine, which has reached clinical trials, and to the anti-Candida albicans and anti-Histoplasma capsulatum ribosomal vaccines. Also covered are vaccination experiments in compromised hosts aimed at eliciting acquired resistance to opportunistic fungal infections which constitute risk factors for these hosts. Immunization procedures include live, killed, and attenuated organisms, as well as different subcellular fractions such as cytoplasmic extracts, fungal culture filtrates, cell walls, or ribosomal fractions. A variety of experimental animal models and isolated human trials constitute the subjects in these studies. Acquired immunity has been evaluated through assessment of resistance to infection and determination of specific immune responses. It has been demonstrated that fungal vaccines do elicit both humoral and cell-mediated immunity in the immunized host. For some vaccines (e.g., H. capsulatum), a correlation between the induced immunity and protection was observed and the immunity could be adoptively transferred. In view of the potential of vaccines against fungal infections, a perspective on their applicability, significance, and value for human use is discussed.