H-2 antigens incorporated into phospholipid vesicles interact specifically with allogeneic cytotoxic T lymphocytes

Subcellular fractions containing different H-2 antigens were tested for their ability to inhibit specific T cell-target cell conjugate formation. H-2-containing membrane vesicles, lentil-lectin-purified H-2 antigens solubilized with detergent (referred to in the text as high-density fraction) or incorporated into lipid vesicles, inhibited T cell-target cell conjugate formation effectively and specifically. However, two- to threefold more protein was required to inhibit T cell-target cell conjugate formation when detergent-solubilized lentil-lectin-purified H-2 antigens were tested. This suggests that a lipid matrix is advantageous for interaction with anti-H-2 T-cell receptors. Experiments were also undertaken to demonstrate specific binding of liposomes containing ¹²⁵I-labeled H-2 antigen to anti-H-2-specific cytotoxic T lymphocytes (CTLs). The binding of the ¹²⁵I-labeled H-2-containing liposomes was saturable and was specifically inhibited by unlabeled H-2 antigens. Monospecific anti-H-2 sera specifically inhibited the binding of liposomes containing H-2 antigen to the CTLs. The results suggest that a specific interaction can occur between serologically defined H-2 antigens and the receptor of anti-H-2 CTLs.