title: Screening of F.VIII:C antibodies by an enzyme-linked immunosorbent assay.
abstract: An enzyme-linked immunosorbent assay (Elisa) method was developed in order to examine prevalence and titer of antibodies directed against the factor VIII coagulant protein (F.VIII:C) in hemophilia A and nonhemophilia A patients. Highly purified F.VIII:C was used as immunosorbent on microtiter plates with a peroxidase-conjugated goat anti human IgG antibody for F.VIII:C antibody detection. Results determined by Elisa were compared with measurements according to the Bethesda method. Initially 24 plasma samples containing an F.VIII:C inhibitory activity ranging from 0 to 7,700 Bethesda units (BU) were analysed. At plasma dilutions of 1:128 the optical density determined by our Elisa measurement and the corresponding BU showed a logarithmic correlation. The coefficient of correlation was r = 0.92 with a standard deviation of 0.002 from the regression curve. Plasma samples were analysed from 53 hemophilia A patients, from 21 nonhemophilia patients with acquired F.VIII:C antibodies and from 460 randomly selected nonhemophilia patients presenting for routine preoperative coagulation examination. F.VIII:C antibody-positive Elisa results and positive BU were found in 7 hemophilia A patients and the 2 patients with a history of acquired F.VIII:C antibodies. Positive Elisa results and negative BU were found in 1 hemophilia A patient and 25 out of 460 nonhemophilia A patients (5.43%) suggesting F.VIII:C antibodies without inhibitory potency on F.VIII:C in these cases.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Internal Medicine, University Hospital, Frankfurt, FRG.
authors.forename: W
authors.initials: W
authors.lastname: Mondorf
authors.forename: S
authors.initials: S
authors.lastname: Ehrenforth
authors.forename: Z
authors.initials: Z
authors.lastname: Vigh
authors.forename: J
authors.initials: J
authors.lastname: Last
authors.forename: G
authors.initials: G
authors.lastname: Tippmann
authors.forename: W
authors.initials: W
authors.lastname: Kreuz
authors.forename: I
authors.initials: I
authors.lastname: Scharrer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood* / Q000276:immunology; D001327:Autoimmune Diseases / Q000097:blood / Q000276:immunology; D001778:Blood Coagulation Disorders / Q000097:blood / Q000276:immunology*; D001780:Blood Coagulation Tests; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005169:Factor VIII / Q000276:immunology*; D005260:Female; D006467:Hemophilia A / Q000097:blood / Q000276:immunology*; D006801:Humans; D007518:Isoantibodies / Q000097:blood* / Q000276:immunology; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D011300:Preoperative Care
chemical_list: D001323:Autoantibodies; D007518:Isoantibodies; D005169:Factor VIII