Macrophage and Experimental Fungal Infection

Abstract

Specific and non-specific host defence mechanisms against Candida albicans infection, cell mediated immunity in particular, were investigated with mice. Susceptibility of mice to the infection with age was first studied. Transitory increase in resistance was observed with 4-week-old mice. The resistance to the infection was reinstated and maintained relatively constant after 5th week. Synthetic and cytotoxic antitumor agents which apparently impair immunocompetent cells suppressed host defence, while PICIBANIL, streptococcal immunopotentiator, enhanced the resistance. Congenitally athymic nude mice showed almost the same resistance as that of their heterozygotes with a heavy inoculum, and decreased resistance with a smaller inoculum. No significant difference in the function of macrophages from both mice was also noticed. Peritoneal macrophages obtained from the mice intraperitoneally immunized with living cells showed enhanced phagocytosis, but intracellular cell killing remained unchanged so far as viable counts are concerned. These experimental results indicated the important role of macrophage in fungal infection.