title: Biochemical characterisation of the haemophilias on the Witwatersrand.
abstract: Blood samples obtained from patients on the Witwatersrand with haemophilia A, haemophilia B and von Willebrand disease were analysed. Factor activities were assayed by conventional methods. Immunoradiometric assay using labelled monoclonal anti-VIIIC:Ag was developed to assay factor VIIIC:Ag in haemophilia A. Factor IX:Ag levels were determined by a commercial ELISA kit. Multimer pattern analysis of von Willebrand factor was performed by agarose gel electrophoresis and Western blotting. In 43 patients haemophilia A was severe, in 8 it was moderate and in 2 it was mild. Factor VIIIC:Ag was undetected in 36 haemophiliacs (CRM-) while VIIIC:Ag was detected in levels exceeding or correlating with those of VIII:C in 17 cases (CRM+). Four severe, CRM- haemophiliacs were found to have inhibitors. An assay of IX:Ag in 6 severely and 2 moderately affected patients with haemophilia B revealed 6 to be CRM- while 2 were CRM+. Multimer pattern analysis was performed on 11 von Willebrand disease patients, of which 5 were type I, 5 were type II and 1 was type III. More informative techniques for the diagnosis and classification of haemophilia are now available. In addition, these results will assist in further molecular studies of these disorders.
authors.affiliation: Department of Haematology, School of Pathology of the South African Institute for Medical Research, Johannesburg.
authors.forename: M G
authors.initials: MG
authors.lastname: van Wijk
authors.forename: R
authors.initials: R
authors.lastname: Cohn
authors.forename: E
authors.initials: E
authors.lastname: Hartman
authors.forename: P M
authors.initials: PM
authors.lastname: Atkinson
mesh_terms: D004587:Electrophoresis, Agar Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005164:Factor IX / Q000032:analysis; D005169:Factor VIII / Q000032:analysis; D006467:Hemophilia A / Q000097:blood*; D002836:Hemophilia B / Q000097:blood*; D006801:Humans; D011863:Radioimmunoassay; D013019:South Africa; D014842:von Willebrand Diseases / Q000097:blood*; D014841:von Willebrand Factor / Q000032:analysis
chemical_list: D014841:von Willebrand Factor; D005169:Factor VIII; D005164:Factor IX