The genetic restrictions of the activation of third-order suppressor cells (Ts3) were studied in mice, using two different types of anti-azobenzenearsonate (ABA)-immune responses, namely delayed-type hypersensitivity (DTH) and cytotoxic T lymphocyte (CTL) generation. Ts2 cells were induced in several different strains of mice by injecting monoclonal T hybridoma molecules or first-order suppress...