Contribution of the erythrocyte matrix to the formation of rosettes by idiotype-specific lymphocytes

Immunosuppression of a cross-reactive idiotype associated with anti- p -azophenylarsonate (anti-Ar) antibodies of A/J mice, followed by hyperimmunization, causes the appearance of substantial percentages of T cells with anti-idiotypic specificity. The T cells were identified through their capacity to form rosettes with autologous (A/J) erythrocytes coated with Fab fragments bearing the idiotype. We report here that the RBC are a significant factor in determining the capacity of the lymphocytes to form rosettes. Relatively low numbers of rosettes were observed when the RBC were derived from species other than the mouse or from certain strains of mice. The property is not determined by the H-2 haplotype but is controlled by one or more genes that are closely linked to the H-2 locus, as shown by data obtained with RBC of several congenic strains. In an F 1 hybrid the property is dominant, suggesting a positive contribution of the RBC rather than the effect of an inhibitor. Also, idiotype-specific lymphocytes from C.AL-20 mice, which possess the allotype of the AL/N strain on a BALB/c genetic background, form rosettes much more efficiently with coated RBC from C.AL-20 or BALB/c mice than with A/J RBC; the opposite is true of idiotype-specific lymphocytes from A/J mice. This provides further evidence for complementary interaction between the lymphocytes and RBC.