Adherence of Candida species to human epidermal corneocytes and buccal mucosal cells: correlation with cutaneous pathogenicity

Abstract

Adherence of microorganisms to epidermal corneocytes may be a prerequisite for cutaneous colonization and infection. Six species of Candida were assayed in vitro for adherence to human epidermal corneocytes and buccal mucosal cells, and compared to previous studies of pathogenicity in a rodent model of cutaneous candidiasis. C. albicans and C. stellatoidea exhibited marked adherence to both epithelial cell types over time, and were cutaneous pathogens in the rodent model. The remaining species showed little or no adherence, and were nonpathogenic to skin. Adherence to corneocytes was not inhibited by ethylenediamine tetraacetic acid, mannan polysaccharide, or concanavalin A lectin. Fresh human serum, but not heat-inactivated serum, inhibited C. albicans adherence by 50%, and was associated with the deposition of complement components, C3 and factor B on blastospores. Adherence to epithelial corneocytes and mucosal cells is a property of pathogenic species of Candida, and may participate in cutaneous colonization and infection mechanisms. Adherence was time-dependent, and did not require divalent cations. Cell wall mannan may participate in the "adhesin" complex. Mannan activation of serum complement and deposition of C3 and factor B on blastospores may provide a protective action by inhibiting Candida adherence to corneocytes.