Restricted helper function of F1 hybrid T cells positively selected to heterologous erythrocytes in irradiated parental strain mice. II. Evidence for restrictions affecting helper cell induction and T-B collaboration, both mapping to the K-end of the H-2 complex.
Studies with H-2-congenic and recombinant strains showed that when F1 hybrid T cells were activated to sheep erythrocytes in irradiated mice of parental strain or related strain, a population of helper cells was generated which collaborated only with B cells sharing the K-end of the H-2 complex with the strain used for activation. No evidence was found that the restriction in helper function (a) reflected a deficiency of appropriate macrophages during T-B collaboration, or (b) was influenced by the Ig allotype of the B cells. It was concluded that the results signified restrictions acting at both the level of helper cell induction (presumed to be a reflection of T-macrophage interactions in the irradiated intermediate hosts) and during T-B collaboration. With (CBA X C57BL/6)F1 cells, the restrictions at each level mapped to the same region i.e. to the left of the I-B subregion. Consequently, one gene (or set of genes) might control restriction at both levels. If so, T-cell recognition of major histocompatibility complex-associated antigen on macrophages and on specific B cells would be either identical or very similar. The fact that genes mapping to the K-end of the H-2 complex also control the restrictive interactions of homozygous T cells implies that F1 T cells behave functionally as a mixture of T cells derived from the two parental strains. Positive selection to antigen in parental strain mice appears simply to alter the ratio of these two populations.
D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000276:immunology*; D002874:Chromosome Mapping; D004912:Erythrocytes / Q000276:immunology; D008040:Genetic Linkage; D006183:H-2 Antigens / Q000235:genetics*; D006579:Heterozygote; D007156:Immunologic Memory; D007165:Immunosuppression Therapy; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D013601:T-Lymphocytes / Q000276:immunology*
D006183:H-2 Antigens