T cell clone-specific alloantisera that inhibit or stimulate antigen-induced T cell activation.

Pigeon cytochrome c-specific, IL 2-secreting T cell hybrids have been used for immunizations to generate alloantibodies against the T cell antigen receptor on these cells. The B10.A-derived cloned T cell hybrid 2B4 was emulsified in complete Freund's adjuvant and injected i.p. into several F1 strains of mice. After boosting the recipient animals with cells in incomplete Freund's adjuvant, malignant ascites developed. In the (BALB/c X AKR)F1 or (AKR X BALB/c)F1 strains, these ascites consistently contained material that specifically inhibited the antigen-induced IL 2 secretion of only the immunizing 2B4 cell. The inhibitory material was antibody that specifically bound and could be absorbed only by 2B4. A similar immunization was performed with the cell 2C2. Although this cell apparently has similar antigenic fine specificity as 2B4, high concentrations of ascites generated by 2C2 immune animals inhibited antigen-induced IL 2 release only from 2C2. At lower concentrations of ascites, this preparation synergized with antigen to increase the IL 2 release, again only from 2C2. This antibody preparation did not affect concanavalin A-induced IL 2 release. The most likely explanation for these data is that the ascites contain antibodies that react with the antigen-specific receptor on the T cell hybrids.