Abstract
Various aspects of double immunodiffusion for the detection of anti-nRNP antibody were studied. Whole calf thymus extract or rabbit thymus acetone powder extract was suitable for the antigen source. The optimal concentration of antigen was between 50 and 100 mg protein/ml. Forty-eight hours was most suitable for the incubation time. An optimal concentration of Agarose gel was around 0.6%. The volume of the antigen (50 mg/ml) poured was satisfactory when more than 100μg of the antigen was used. Antigenic activiy was still present in calf thymus extract which had been stored for three years at -20°C.
