Further characterization of human salivary anticandidal activities in a human immunodeficiency virus-positive cohort by use of microassays

Salivary anticandidal activities play an important role in oral candidal in fection. R. P. Santarpia et al, (Oral Microbiol, Immunol, 7:38-43, 1992) de veloped in vitro anticandidal assays to measure the ability of saliva to in hibit the viability of Candida albicans blastoconidia and the formation of germ tubes by C. albicans, In this report, we describe modifications of the se assays for use with small volumes of saliva (50 to 100 mu l). For health y subjects, there is strong inhibition of blastoconidial viability in stimu lated parotid (75%), submandibular-sublingual (74%), and whole (97%) saliva , as well as strong inhibition of germ tube formation (>80%) for all three saliva types. The susceptibility of several Candida isolates to inhibition of viability by saliva collected from healthy subjects is independent of bo dy source of Candida isolation (blood, oral cavity, or vagina) or the susce ptibility of the isolate to the antifungal drug fluconazole. Salivary antic andidal activities in human immunodeficiency virus (HIV)-infected patients were significantly lower than those in healthy controls for inhibition of b lastoconidial viability (P < 0.05) and germ tube formation (P < 0.001), Sti mulated whole-saliva flow rates were also significantly lower (P < 0.05) fo r HIV-infected patients. These results show that saliva of healthy individu als has anticandidal activity and that this activity is reduced in the sali va of HIV-infected patients. These findings may help explain the greater in cidence of oral candidal infections for individuals with AIDS.