Biomaterial Database

Immunologic studies of factor IX (Christmas factor). II. Immunoradiometric assay of factor IX antigen. 1978

H C Yang

A solid-phase two-site immunoradiometric assay has been developed which measures factor IX antigen levels as low as 0.0004 u per ml of plasma. In normal individuals, the factor IX antigen level correlated with the factor IX procoagulant level. In haemophilia B, 14 patients had markedly reduced antigen levels (less than 0.06 u/ml) and five had normal levels (greater than 0.60 u/ml).

UI	MeSH Term	Description	Entries
D011863	Radioimmunoassay	Classic quantitative assay for detection of antigen-antibody reactions using a radioactively labeled substance (radioligand) either directly or indirectly to measure the binding of the unlabeled substance to a specific antibody or other receptor system. Non-immunogenic substances (e.g., haptens) can be measured if coupled to larger carrier proteins (e.g., bovine gamma-globulin or human serum albumin) capable of inducing antibody formation.	Radioimmunoassays
D002836	Hemophilia B	A deficiency of blood coagulation factor IX inherited as an X-linked disorder. (Also known as Christmas Disease, after the first patient studied in detail, not the holy day.) Historical and clinical features resemble those in classic hemophilia (HEMOPHILIA A), but patients present with fewer symptoms. Severity of bleeding is usually similar in members of a single family. Many patients are asymptomatic until the hemostatic system is stressed by surgery or trauma. Treatment is similar to that for hemophilia A. (From Cecil Textbook of Medicine, 19th ed, p1008)	Christmas Disease,Factor IX Deficiency,Deficiency, Factor IX,F9 Deficiency,Haemophilia B,Hemophilia B Leyden,Hemophilia B(M),Plasma Thromboplastin Component Deficiency,Bs, Hemophilia,Deficiencies, F9,Deficiencies, Factor IX,Deficiency, F9,Disease, Christmas,F9 Deficiencies,Factor IX Deficiencies,Haemophilia Bs,Hemophilia Bs,Hemophilia Bs (M)
D005164	Factor IX	Storage-stable blood coagulation factor acting in the intrinsic pathway of blood coagulation. Its activated form, IXa, forms a complex with factor VIII and calcium on platelet factor 3 to activate factor X to Xa. Deficiency of factor IX results in HEMOPHILIA B (Christmas Disease).	Autoprothrombin II,Christmas Factor,Coagulation Factor IX,Plasma Thromboplastin Component,Blood Coagulation Factor IX,Factor 9,Factor IX Complex,Factor IX Fraction,Factor Nine,Factor IX, Coagulation
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000941	Antigens	Substances that are recognized by the immune system and induce an immune reaction.	Antigen