Radioimmunoassay for immunoconglutinins.
A competitive radioimmunoassay for immunoconglutinin (IK) was developed using isolated antostimulated rabbit IK labelled with 125I and glutaraldehyde-fixed sheep erythrocytes coated with fixed complement (EAC). IKs in test sera of human or animal origin produced specific inhibition of uptake of [125I]IK onto EAC and this was quantitated by reference to a calibration curve established with pure rabbit IK. Among 20 normal human sera the IK levels were: median 62 microgram/ml, range 41-170 microgram/ml and in 7 rat sera the levels were: median 71 microgram/ml, range 58-80 microgram/ml. Preliminary studies showed raised IK levels in the sera of patients with rheumatoid arthritis and with Crohn's disease.
D000818:Animals; D001172:Arthritis, Rheumatoid / Q000276:immunology; D001323:Autoantibodies; D001667:Binding, Competitive; D003165:Complement System Proteins / Q000276:immunology*; D003424:Crohn Disease / Q000276:immunology; D000939:Epitopes; D006801:Humans; D011817:Rabbits; D011863:Radioimmunoassay; D012756:Sheep / Q000097:blood
D001323:Autoantibodies; D000939:Epitopes; D003165:Complement System Proteins