The dendritic cell-specific C-type lectin DC-SIGN is a receptor for Schistosoma mansoni egg antigens and recognizes the glycan antigen Lewis x.

摘要: Schistosoma mansoni soluble egg antigens (SEAs) are crucially involved in modulating the host immune response to infection by S. mansoni. We report that human dendritic cells bind SEAs through C-type lectin cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN). Monoclonal antibodies against carbohydrate Lewisx (Lex) and GalNAcbeta1-4(Fucalpha1-3)GlcNAc (LDNF) inhibit binding of DC-SIGN SEAs, suggesting these glycan may be critically binding. In a solid-phase adhesion assay, DC-SIGN-Fc binds polyvalent neoglycoconjugates contain Lex antigen, whereas no was observed Galbeta1-4GlcNAc, containing only alpha-fucose or oligosaccharides with terminal alpha1-2-linked fucose is low. These data indicate antigen fucose-dependent adjacent monosaccharides and/or anomeric linkage important for activity. Previous studies have shown HIV gp120 contains high-mannose-type N-glycans. Site-directed mutagenesis within recognition domain (CRD) demonstrates amino acids E324 E347 gp120, Lex, SEAs. By contrast, mutation acid Val351 abrogates but not gp120. suggest recognizes ligands different (but overlapping) regions its CRD. Our imply pathogen receptor also function interaction possibly LDNF, which found on pathogens, such as schistosomes bacterium Helicobacter pylori.