Effect of antibodies on the respiration and morphology of Candida Albicans

Respirometry was used to study the effect of antibodies to Candida albicans on the gowth of this species in vitro. Blastospore suspensions were pre-incubated with rabbit hyperimmune and normal serum and rabbit antibody and normal gamma globulin at 37 degrees C for 30 minutes. They were then inoculated into respirometer flasks containing a semi-synthetic medium and oxygen consumption was measured at 27 degrees C. Rabbit antiserum to C. albicans serotype A inhibited the growth, as measured by O2 consumption, of serotyped A and B strains of C. albicans. The amount of inhibition appeared to be related to the prevention or retardation of germ tube formation. The growth of blastospores incubated with normal rabbit serum was filamentous, whereas, blastospores incubated with antiserum remained in the yeast phase. Inhibition of O2 consumption and retardation of germ tube formation was also demonstrated with the purified gamma-globulin fraction of the antiserum.