Masuoka J, Wu G, Hazen KC; American Society for Microbiology. General Meeting.
Abstr Gen Meet Am Soc Microbiol. 1998 May 17-21; 98: 257 (abstract no. F-28).
Dept. Pathology, Univ. Virginia Med. Ctr., Charlottesville, USA.
Development of candidiasis by C. albicans involves attachment of fungal cells to extracellular matrix (ECM) proteins. Recent studies reveal that hydrophobic C. albicans cells bind better than hydrophilic cells to ECM, but evidence supporting a role of hydrophobic proteins or hydrophobic interactions participating in the adhesion event has been lacking. To evaluate these possibilities, adhesion of hydrophobic yeast cells to immobilized laminin (Ln) or fibronectin (Fn) in the presence of KCl or KSCN was assessed. Less binding (% of cells bound) occurred in the presence of KSCN versus KCl indicating hydrophobic interactions were involved. Hydrophobic peptides derived from the flanking region of the RGD sites of Ln and Fn inhibited hydrophobic yeast cell attachment to Ln and Fn. The effect of the peptides was concentration dependent. Inhibition by the peptides was concentration dependent. Monoclonal antibody, MAb 6C5CA, which recognizes a cell wall, hydrophobic protein antigen from C. albicans, also inhibited yeast cell adhesion to Fn and Ln when compared to isotype-matched MAb. This result was further substantiated with a competitive ELISA assay in which soluble Fn and Ln blocked by 14-16% the epitope sites on the antigen recognized by MAb 6C5CA. A random peptide display system was used to determine the possible epitope of MAb 6C5CA. Preliminary results suggest that the epitope contains a hydrophobic peptide motif. These results indicate that the hydrophobic antigen from the C. albicans cell wall is involved in attachment to ECM and that the interaction of the antigen with ECM involves cognate hydrophobic peptide regions. Thus, the attachment of C. albicans to ECM may be driven more by chemistry, namely hydrophobic interactions, than interactions between structurally complementary adhesins and ECM cell binding sites.
Publication Types:
Keywords:
- Adhesions
- Adhesiveness
- Antibodies, Monoclonal
- Antigens, Fungal
- Candida albicans
- Candidiasis
- Case-Control Studies
- Cell Adhesion
- Cell Wall
- Cell-Matrix Junctions
- Extracellular Matrix
- Extracellular Matrix Proteins
- Fibronectins
- Laminin
- Oligopeptides
- arginyl-glycyl-aspartic acid
- immunology
Other ID:
UI: 102226503
From Meeting Abstracts