Characterization of carbohydrate specificity of monoclonal antibodies to fungal antigenic markers using biotinylated oligosaccharides as coating antigens
摘要
Mannan and β-(1→3)-glucan are two polysaccharide markers that are characteristic for a number of fungal pathogens, including Candida albicans, which is the most common cause of invasive mycoses in humans. In this study, we examined the epitope specificity of two monoclonal antibodies, CM532 and FG70, which recognize certain oligosaccharide fragments from these fungal polysaccharides. Using a panel of biotinylated oligosaccharides as coating antigens, we found that antibody CM532, obtained by immunization with a pentamannoside β-Man-(1→2)-β-Man-(1→2)-α-Man-(1→2)-α-Man-(1→2)-α-Man KLH conjugate, selectively recognizes the trisaccharide β-Man-(1→2)-α-Man-(1→2)-α-Man epitope. Another antibody, FG70, obtained by immunization with heptaglucan β-Glc-(1→3)-[β-Glc-(1→3)]5-β-Glc with KLH, interacts with a linear β-(1→3)-linked pentaglucoside fragment, and the presence of 3,6-branches within this epitope does not significantly affect the interaction efficiency. The data obtained indicate that the monoclonal antibodies under consideration can be used to create currently lacking effective diagnostics for the detection of fungal infections.