Hapten-reactive T and B mouse lymphocytes. Affinity of antibodies and binding strength of cellular receptors as factors of dose and time after immunization.

Abstract

The kinetics of development of anti‐hapten‐Kactive T and B cells in groups of mice immunized against different dotes of two hapten‐protein conjugates was measured at different times. after a primary immunization with a single batch of conjugated sheep erythrocytes. In addition, the affinity of the receptors on the specific antigen‐reactive cells was determined. Immunogenic doses of NNP‐HGG varied from 40μg to 2mg, whereas 0.4μg even with adjuvant were nonimmunogenic .The affinity of antibodies secreted by single cells was measured by a modification of the local hemolysis in‐gel assay with different concentrations of free hapten incorporated in the .agar. which showed a marked shift in affinity for i.PFC in contrast to d.PFC with time The affinityof receptor bearing antigen‐binding cells of both T and B origin was also Studied by a hapten inhibition assay With the aid of specific antisera against T and B spleen lymphoid cells. pure population of T or B cells could be obtained from spleens of mice immunizedwith different hapten‐protein conjugates .The binding strength of antigen‐binding B cells increased with time after immunization, whereas that of antigen‐binding T cells did not. The results are discussed in the light of recent studies on the structure of the T‐cell receptor