Effect of candida glabrata β-glucans on immunosuppressive properties of dendritic cells

Abstract

β-glucan is a polysaccharide and consists of the backbone of β-(1, 3)-glucan and/or β-(1, 6)-glucan structures. β-glucans are extracted from the cell wall of Candida sp, including Candida glabrata. Interestingly, the biological activity of Candida β-glucan has been represented as a stimulator in the mechanism of immune responses. Dendritic cells are powerful antigen-presenting cells that play a significant role in both innate and adaptive immunity. In the present study, we evaluated the effect of C. glabrata β-glucans on dendritic cell (DC) immunologic responses. Firstly, bone marrow-derived DCs (BMDCs) were induced with C. glabrata β-glucans in a dose-dependent manner. The expression of CD80, CD86, CD40, and MHCII in BMDC markedly increased after stimulation. C. glabrata β-glucan-stimulated BMDCs significantly enhanced the production of immunosuppressive cytokine, interleukin-10 (IL-10). Secondly, BMDC after stimulation could promote a high level of IL-10 secretion by T cells. IL-10 plays a critical role in limiting the inflammatory immune response and its ability to mediate the immunosuppressive response. Furthermore, the level of serum anti-(double-stranded)-DNA antibodies promisingly decreased in Fcgr2b-/- lupus-prone mice after C. glabrata β-glucans immunization in an in vivo experiment. Our results imply that C. glabrata β-glucans have the induction of immunosuppressive responses in dendritic cells and T cells and may be beneficial for the amelioration of lupus disease.