Effect of Inactivated C. Albicans on Natural Killer (NK) Cell Activity and Blastogenesis in Mice

Abstract

The Candida albicans (CA) is an important example of microbial cell with antitumor adjuvant activity (1). Our previous in vivo data are compatible with the hypothesis that CA antitumor activity could be strictly dependent on an intact T-cell compartment since this antitumor effect is not obtained in congenitally athymic mice or in animals treated by total-body irradiation (3). On the other hand, CA does not seem to be able to augment the in vitro expression of splenic natural killer (NK) cell activity which could exclude a possible role of NK lymphocytes in the CA-induced antitumor activity (3). However, since induction of NK cells with cytotoxic activity against tumor cells, as has been shown in the peritoneal cavity of mice treated with BCG (8) or C. parvum (5), we examined in the present study possible effect of CA administration on peritoneal NK cell activity. We also examined the in vitro response to mitogens of spleen cells from CA-treated mice.