title: Measurement of complement proteins C2 and B in systemic lupus erythematosus and septic shock.
abstract: We developed sensitive radioassays to quantitate the homologous complement proteins C2 and B, in intact form, in sera from patients with diseases associated with hypocomplementemia. In a study of systemic lupus erythematosus (SLE) patients, we found a subset of patients (6/40) with low C2 concentrations, though overall, C2 concentration was not related to disease activity. Protein B concentration was increased in 23/40 SLE patients, apparently not due to a generalized acute phase response. Among patients with both gram-negative and gram-positive septic shock, C2 and B concentrations were low in a subset of patients with pre-existing cirrhosis, suggesting hepatic hyposynthesis of these proteins may be important in their prognosis and predisposition to severe infections.
authors.affiliation: Department of Medicine University of Alabama, Birmingham.
authors.forename: T J
authors.initials: TJ
authors.lastname: Oglesby
authors.forename: D R
authors.initials: DR
authors.lastname: Schultz
authors.forename: R M
authors.initials: RM
authors.lastname: Schein
authors.forename: C L
authors.initials: CL
authors.lastname: Sprung
authors.forename: J E
authors.initials: JE
authors.lastname: Volanakis
mesh_terms: D015415:Biomarkers / Q000097:blood*; D003167:Complement Activation; D003175:Complement C2 / Q000032:analysis*; D011415:Complement Factor B / Q000032:analysis*; D004792:Enzyme Precursors / Q000032:analysis*; D006801:Humans; D008103:Liver Cirrhosis / Q000097:blood / Q000276:immunology; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology*; D012772:Shock, Septic / Q000097:blood / Q000276:immunology*
chemical_list: D015415:Biomarkers; D003175:Complement C2; D004792:Enzyme Precursors; D011415:Complement Factor B