Further Studies in Methods of Induction and Specificity of Leukocyte Isoantibodies in Humans

Eleven volunteers have been immunized by s.c. injections of washed leukocyte suspensions, each from a single donor. Agglutinins and complement-fixing antibodies to leukocytes were demonstrable in 30–106 days after the initial injection and have persisted up to 450 days from the time of the last booster antigen. Immunizing donors were paired on the basis of their leukocyte reactions with previously induced leukocyte antisera, with the goal of inducing sera which would recognize previously identified specificities. Two of these sera did so. Cross absorption studies indicate that none of the sera are monospecific, but four of these are of fairly high specificity and three others may be considered of moderate specificity. Reaction to these sera with cells of 219 random donors indicates significant correlations in activity between several of the sera thus produced. Although more laborious than the harvesting of maternal antisera, this technique of induction is safe and practical.