title: The role of Staphylococcus aureus cell-wall peptidoglycan, teichoic acid and protein A in the processes of complement activation and opsonization.
abstract: The role of cell-wall peptidoglycan, teichoic acid and protein A in the processes of Staphylococcus aureus complement activation and opsonization was investigated. CH50 consumption studies reveal that, although all cell-surface fractions were capable of activating the classical C pathway, only peptidoglycan consumed C via the alternative pathway. Using a quantitative immunofluorescence assay, peptidoglycan was shown to bind C3 molecules via the classical as well as via the alternative C pathway and in the absence of IgG and IgA class antibodies. C activation via the classical and the alternative pathway could be distinguished by kinetic analysis. By comparing the rates of staphylococcal C consumption, C3 fixation and opsonization it was found that the CH50 consumption assay is a relatively insensitive method and may yield results that do not necessarily reflect the process of bacterial opsonization.
mesh_terms: D003167:Complement Activation; D003175:Complement C2 / Q000276:immunology; D003176:Complement C3 / Q000276:immunology; D003168:Complement Fixation Tests; D007700:Kinetics; D009895:Opsonin Proteins; D010457:Peptidoglycan / Q000276:immunology*; D013205:Staphylococcal Protein A / Q000276:immunology*; D013211:Staphylococcus aureus / Q000276:immunology*; D013682:Teichoic Acids / Q000276:immunology*
chemical_list: D003175:Complement C2; D003176:Complement C3; D009895:Opsonin Proteins; D010457:Peptidoglycan; D013205:Staphylococcal Protein A; D013682:Teichoic Acids