Influence of Igh-linked gene products on the generation of T helper cells in the response to sheep erythrocytes

The role of Igh-linked loci in the generation and expression of T cell help for antibody responses to sheep erythrocytes (SRBC) was investigated. The production of IgM, IgG3, IgG1, IgG2b, and IgG2a antibody to SRBC was shown to be T cell dependent. The Igh-congenic mouse pair CBA/Tufts (Ighj) and CBA.Ighb gave equivalent responses to SRBC. CBA.nude mice (Ighj) supplemented with peripheral T cells of either Ighj or Ighb genotype produced equivalent, high responses. Therefore, T cell-B cell mismatching for the Igh haplotype is not in itself a bar to the generation or expression of help. In contrast, T cells primed in an environment that lacks Ighj-linked products are inefficient helpers for Ighj B cells. These results suggest that antigen-primed B cells or their products prime a set of T cells that can help B cells that bear matching, Igh-linked gene products.