Idiotype‐specific neonatal suppression of phosphorylcholine‐responsive B cells

The effect of neonatal anti‐idiotypic suppression on the expression of B cells of the T15 clonotype has been investigated at the level of individual clonal precursor cells. The results indicate that B cells of the T15 clonotype are almost completely eliminated from the repertoire for four months after neonatal injection of allogeneic anti‐idiotypic serum. The degree of this suppression is dependent on the amount of anti‐idiotypic antibody administered and is less profound if anti‐idiotypic antibody is given after the first week of life. No suppression was observed when anti‐idiotypic antisera were administered to mice 30 days of age or older, which may indicate that immature B cells are the population most susceptible to suppression. However, since suppression could be reversed by administration of T15 myeloma protein several days after injection of anti‐idiotype, the inability to suppress adult BALB/c mice may have been due to the high level of T15 idiotype normally present in their serum. Finally, phosphorylcholine‐responsive B cells of identifiable clonotypes other than T15, even a clonotype sharing antigen‐combining site determinants with T15, appear unaffected by anti‐T15 suppression.