Immunoregulatory circuits which modulate responsiveness to suppressor cell signals: contrasuppressor cells can convert an in vivo tolerogenic signal into an immunogenic one

Abstract

The intravenous injection of 2,4,6‐trinitrophenyl (TNP)‐labeled peritoneal exudate cells (TNP‐PEC) into CBA mice fails to produce a state of hypersensitivity; rather, it renders recipient mice incapable of mounting a contact hypersensitivity response when they are subsequently immunized with a reactive form of the specific hapten. However, if precultured neonatal spleen cells are injected along with the cells that induce tolerance (TNP‐PEC), not only is the development of tolerance inhibited but sensitization to TNP develops. The neonatal spleen cell responsible for turning the tolerogenic signal into an immunogenic one is I‐J⁺ and adheres to the Vicia villosa lectin. Thus, it expresses markers that distinguish contrasuppressor effector cells from helper cells (D. R. Green et al., Eur. J. Immunol. 1981. 11: 973), indicating that activated contrasuppressor cells can act as potent, helpful regulatory cells in vivo.