Estimation of IgG and IgM brucella antibodies in infected and non-infected persons by a radioimmune technique.

Sera from 105 blood donors and eight patients with brucellosis were examined for anti-brucella IgG and IgM by a radioimmune technique. A pooled standard was used for comparison and evaluation. The upper limit of the 99% confidence interval on the mean of both immunoglobulin classes in blood donor sera was below 7 units/ml. Antibody response was shown in three acute, two relapsing, two chronic, and one asymptomatic cases. Values of up to 300 units/ml of both classes were found in the acute cases. Chronic sufferers showed lower concentrations of antibody. Relapsing cases showed increases comprising mainly IgG. The assay method, which shows general concordance with the results of conventional tests. is useful and measures individual immunoglobulin classes directly.