title: Activation of the alternative complement pathway by mannose-binding lectin via a C2-bypass pathway.
abstract: MBL is a serum lectin that activates the lectin pathway of the complement system. MBL forms complexes with three types of MASPs. Upon binding to Salmonella serogroup C-specific oligosaccharide, MBL activates the alternative pathway via a C2-bypass pathway without involving MASP-2, C2 or C4. We demonstrate that mannan-bound MBL activates the alternative pathway via a C2-bypass pathway that requires MASP-2 and C4. Thus, depending on the ligands to which MBL binds, there may be two distinct MBL-mediated C2-bypass pathways.
authors.affiliation: Department of Applied Biochemistry, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Tateishi
authors.forename: Misao
authors.initials: M
authors.lastname: Matsushita
mesh_terms: D003167:Complement Activation; D003175:Complement C2 / Q000276:immunology* / Q000378:metabolism*; D003181:Complement C4 / Q000276:immunology / Q000378:metabolism; D003170:Complement Pathway, Alternative / Q000276:immunology*; D006801:Humans; D037601:Mannose-Binding Lectin / Q000276:immunology* / Q000378:metabolism*; D050606:Mannose-Binding Protein-Associated Serine Proteases / Q000276:immunology / Q000378:metabolism; D012475:Salmonella / Q000276:immunology
chemical_list: D003175:Complement C2; D003181:Complement C4; D037601:Mannose-Binding Lectin; C105296:MASP2 protein, human; D050606:Mannose-Binding Protein-Associated Serine Proteases