Estimation of Phagocytic activity by normal human peripheral blood mononuclear cells on various oral isolates of Candida species – An in-vitro study

Abstract

Polymorphonuclear neutrophils (PMN) and mononuclear phagocytes represent an important first line and effector function in control of Candida infections. The aim of the study is to determine the in-vitro phagocytic activity of human peripheral blood mononuclear cells against oral isolates of Candida species and its antifungal susceptibility. The study also evaluates the degree of respiratory burst activity of PBMCs. Phagocytic and lytic indices by PBMCs were determined for Candida spp. The respiratory burst activity was evaluated by nitroblue tetrazolium test. Antifungal disc diffusion susceptibility testing was performed. A total of 100 Candida were isolated belonging to the species C.albicans, C. tropicalis, C.krusei and C.auris. Phagocytic and lytic indices of C.albicans was significant when compared to standard strain of C.albicans. For C.tropicalis and C.krusei phagocytic index was significant while lytic index was not significant when compared to standard strain. The inter species comparison of both the indices was not significant for the clinical isolates of Candida. A significant reduction in phagocytic activity was observed for clinical isolates of Candida spp. but lytic activity was variable when compared to the standard strain of C.albicans.

Keywords

• Phagocytic activity
• Candida species
• Respiratory burst
• Nitroblue tetrazolium test
• Antifungal susceptibility