Longitudinal study of anti-Candida albicans mucosal immunity against aspartic proteinases in HIV-infected patients

Oropharyngeal candidiasis (OPC), mainly caused by Candida albicans, is comm only observed in HIV-infected patients. Secreted aspartic proteinases (Saps ) are virulent agents involved in adherence to the mucosal surface and in t issue invasion. The immune secretory response to these agents was investiga ted in 15 HIV-infected patients, during oral yeast colonization and episode s of oropharyngeal candidiasis (OPC), in a 1-year longitudinal study. We de veloped an avidin-biotin-amplified immunofluorometric assay fur the detecti on of specific immunoglobulins G, A, and M against somatic, Sap2 and Sap6 a ntigens. We report increases in anti-somatic, anti-Sap2, and anti-Sap6 sali vary antibodies in patients with OPC. Over the 1-year period, not only OPC episodes but also variations in yeast colonization levels were correlated w ith variations in salivary anti-Sap6 antibody levels. Our results show the ability of HIV-infected patients to produce high levels of salivary antibod ies; however, these antibodies were not efficient in limiting candidal infe ction, probably because of cellular cooperation deficiency and the enhanced virulence of the infecting strain.