Inhibition of adherence of Candida albicans and Candida dubliniensis to a resin composite restorative dental material by salivary secretory IgA and monoclonal antibodies

OBJECTIVE: The attachment of Candida to oral surfaces is a crucial step in the colonization of the oral cavity and the eventual development of oral diseases caused by this microorganism. Inhibition of adhesion is one of the strategies currently studied to prevent Candida infections. The main objective of this study was to investigate the inhibitory effect of the human salivary components on the adherence of Candida albicans and C. dubliniensis to Herculite, a widely used resin composite restorative dental material. We have also investigated the influence on the adherence of three monoclonal antibodies (mAbs) directed against C. albicans cell wall antigens. DESIGN: The adhesion of three strains of C. albicans and one strain of C. dubliniensis was studied by a visual method after incubating the fungus and the resin in presence and in absence of human whole saliva, secretory immunoglobulin A (sIgA) and three mAbs directed against C. albicans cell wall surface antigens. RESULTS: Adherence of C. albicans was inhibited by whole saliva (41.7%), salivary sIgA (55.7%) and the salivary components that bind to the cell wall (36.7%). Whole saliva significantly reduced the adhesion of C. dubliniensis to Herculite to 45.3% of the control level. Saliva previously adsorbed with fungal cells or sIgA depleted saliva had no effect on adherence. An inhibition in the adhesion of C. albicans and C. dubliniensis to Herculite similar to that shown by whole saliva was also observed when mAbs C7 and 26G7 were used. However, mAb 21E6 increased adhesion of all the strains to Herculite. CONCLUSIONS: The results suggest that sIgA, as well as whole saliva, are important in blocking adherence of C. albicans and C. dubliniensis to Herculite and that this effect can be reproduced with mAbs directed against the cell wall surface of C. albicans.