Antigen receptors on major histocompatibility complex-restricted T lymphocytes. I. Preparation and characterization of syngeneic antisera against trinitrophenyl-activated T cell blasts and demonstration of their specificity for idiotypes on cytotoxic T lymphocytes

This paper describes the specificity of AKR anti-(a) [AKR anti- trinitrophenylated AKR (AKR-TNP)] [AKRa (AKRaAKR TNP)] antisera raised in syngeneic AKR mice against AKRaAKR-TNP cell populations enriched for H-2-restricted aTNP cytotoxic lymphocytes (CTL) by blast-cell isolation. The activity of the antisera resided in the Ig fraction. All antisera were shown to reproducibly react with AKRaAKR-TNP-CTL- containing cell populations in indirect immunofluorescence and all removed the major fraction of CTL in complement-dependent lysis causing a considerable depression of cell-mediated lympholysis. The antisera were nonreactive with alloreactive AKRaC57BL/6 CTL and other H-2- restricted AKR CTL against fluorescein-isothiocyanate-conjugated AKR- target cells. It could be excluded that the antisera contained contaminating antibodies against TNP, TNP-neoantigenic determinants (NAD), or processed CTL-receptor-bound TNP-NAD, thus demonstrating specificity for determinants on T cell receptors of AKRaAKR-TNP CTL. These receptors were produced by the CTL themselves. These observations are interpreted to suggest that AKRa (AKRaAKR-TNP) antisera contain anti-idiotypic antibodies directed against specificity-associated determinants (idiotypes) on T cell receptors of H-2-restricted AKRaAKR- TNP CTL. The antisera provide a new tool to study the genetic control of idiotype expression on H-2-restricted CTL, the biochemistry of T cell receptors, and the regulation of the generation of H-2 restricted CTL on the idiotype level.