Complement activation by clumping factor and protein A from Staphylococcus aureus strain E 2371.
Purified surface components from Staphylococcus aureus strain E 2371, which bind to human plasma proteins, were tested for their ability in vitro to activate complement present in normal human serum. Staphylococcal clumping factor as well as protein A both isolated from strain E 2371 were capable of activate complement, while the fibronectin-binding protein showed no activity. At identical molar concentrations clumping factor was more potent than protein A to induce complement consumption. Both clumping factor and protein A were able to activate the alternative complement pathway as demonstrated in serum chelated with ethylene-glycerol-tetra-acetic acid (10 mM) in the presence of MgCl2 (10 mM).
D002846:Chromatography, Affinity; D003030:Coagulase / Q000276:immunology* / Q000302:isolation & purification; D003167:Complement Activation; D006801:Humans; D012685:Sepharose / Q000031:analogs & derivatives; D013205:Staphylococcal Protein A / Q000276:immunology* / Q000302:isolation & purification; D013211:Staphylococcus aureus / Q000276:immunology*
D003030:Coagulase; D013205:Staphylococcal Protein A; C036210:immunoglobulin G-sepharose; D012685:Sepharose