Comparison of salivary IgA and systemic IgA and IgG antibodies to Saccharomyces cerevisiae in HIV-infected subjects

Our objective was to investigate the concentrations of IgA and IgG antibodies to Saccharomyces cerevisiae in whole saliva and serum samples from HIV-infected patients and to compare them with the corresponding antibody values of healthy controls. A cross-sectional design was used. The test group consisted of 23 HIV-infected male individuals, aged 20-41 years old, free of any other systemic disease. Twenty healthy subjects aged 27-43 years old served as controls. Whole unstimulated saliva and blood were collected from all subjects. IgA concentrations in saliva and IgA and IgG concentrations in serum were measured by solid-phase enzyme-linked immunosorbent assay. Salivary antibody concentrations were calculated by reference to a pooled standard saliva obtained from 10 healthy males with high levels of anti-S. cerevisiae antibody activity. Total IgA and IgG concentrations were measured by nephelometry / tholocymetry assay. No significant difference was observed in salivary specific IgA and serum specific IgG levels to S. cerevisiae, while serum specific IgA were significantly lower in HIV infected patients compared to control group. Opportunistic infections due to S. cerevisiae, although rare, cannot be dismissed. This yeast can show a potential virulence in debilitated patients, therefore, further extensive investigation should be considered.