Antigenic relationships between Candida albicans and various yeasts as reflected by immunoglobulin-class specificity

A group of guinea pigs was inoculated into the foot pads with a single dose of Candida albicans in complete Freund's adjuvant, while another group was similarly inoculated once in the foot pads but also several times intramuscularly, with Candida alone. All guinea pigs were bled at different intervals after immunization and sera were separated chromatographically into IgG and IgM fractions. In order to study the antigenic relationships as reflected by immunoglobulin-class specificity, IgG and IgM fractions and whole sera obtained from guinea pigs differently immunized, were tested for the presence of agglutinins against C. albicans, six other species of Candida, and species of the ascosporogenous genera Saccharo-myces, Kluyveromyces and Schizosaccharomyces. The results show that (1) only IgG fractions of the different sera prepared contained the specific anti-C. albicans antibodies; (2) IgG and IgM fractions of the sera obtained from a single inoculation did not reveal a specific pattern expressing antigenic relationships of the yeasts studied, and (3) the IgM fractions of the sera obtained from several inoculations had a more homogenous pattern of reactivity, since mainly these contained the agglutinins against the ascosporogenous yeast species.