title: A simple method for quantitative measurement of C3d in human plasma.
abstract: We describe a simple and reliable method for quantitating C3d in human plasma. The method rests on the finding that native C3 and its activation/inactivation product C3c bind to Concanavalin A, whereas C3d does not. Rocket affinoimmunoelectrophoresis with Con-A Sepharose incorporated into an intermediate gel permits quantitation of free C3d in 2-20 microliters aliquots of EDTA-plasma without any manipulation prior to sample application. Using this method, we found that the level of circulating C3d in plasma of 30 healthy donors was usually well below 3% of maximally convertable C3d.
mesh_terms: D003176:Complement C3 / Q000032:analysis* / Q000378:metabolism; D015933:Complement C3d; D003208:Concanavalin A; D004492:Edetic Acid; D004789:Enzyme Activation; D006801:Humans; D007123:Immunoelectrophoresis, Two-Dimensional / Q000379:methods; D011485:Protein Binding
chemical_list: D003176:Complement C3; D003208:Concanavalin A; D015933:Complement C3d; D004492:Edetic Acid