Immunological Response of Albino Rats Immunized with UV-Killed Candida albicans

The treatments of systemic candidiasis in humans with the current antifungal drugs of choice such as azole derivatives and amphotericin B have raised issues of toxicity and resistance among others. The immunogenic property of killed C. albicans was explored to evoke immunological response in the possible prevention of candidemia. Rats were immunized after acclimatization on two occasions with 10⁶ cells/ml of Ultraviolet radiation killed C. albicans and subsequently challenged with 10⁶ viable C. albicans. Two other groups; positive and negative controls received same dose of viable C. albicans and normal saline respectively. Five rats each from the groups mentioned were bled for the determination of antibody titers and white blood cell differentials. Also, other rats from the three groups were observed for 28 days for survival after challenge to determine the protective effect of the ultraviolet killed C. albicans. The results revealed that Ultraviolet killed C. albicans stimulated a significant amount of antibodies and white blood cell differentials that were immunoprotective. We also found that all immunized rats survived challenge with 10⁶ viable cells while the kidneys of the dead unimmunized rats showed a positive growth of C. albicans. Thus, Ultraviolet killed C. albicans could provide significant protection.