Background: The adherence of microorganisms to host tissue is an important process in the pathogenesis of fungal infection. A protein that shares antigenic and structural homology with the α-subunit of leukocyte adhesion glycoprotein CD11b/CD18, also known as iC3b receptor, Mo-1 or Mac-1, has been isolated from the surface of C. albicans.
Objective: This study was done to observe the changes in the expression of iC3b receptor on C. albicans by glucose or immunosuppressive agents and to elucidate the effect of glucose and anti-iC3b receptor antibodies on adhesion between human dermal microvascular endothelial cells(HDMEC) and C. albicans.
Methods: We utilized immunofluorescence study and immunofluorescent flow cytometry and the binding assay of C. albicans to cultured HDMEC in vitro and blocking assay using monoclonal antibody were performed.
Results: Immunofluorescence study and immunofluorescent flow cytometric analysis demonstrated surface expression of iC3b receptor on C. albicans. The expression of surface iC3b receptor on C. albicans in creased in a dose dependent manner with increasing concentrations of glucose, cyclophosphamide and prednisolone. The adherence of C. albicans to HDMEC correlated positively with glucose levels. The adherence of C. albicans to HDMEC decreased significantly by the treatment with anti-iC3b receptor antibodies.
Conclusion: The results suggest that iC3b receptors should be involved in the adherence of C. albicans to vascular endothelial cells and may be involved in the
pathogenesis of hematogenous candidiasis.