Supramolecular Relationships of Membrane Antigens on the Murine Thymocyte

The topographical relationships of Thy-1, Ly-1, Ly-2, and T200 were examined on the murine thymocyte. The inhibition of the binding of radiolabelled monoclonal antibody after incubation with unlabelled heterologous antibody was used as a measure of the proximity of the target antigens on the cell surface. On unfixed cells, prior incubation with anti-Thy-1.2 impeded the attachment of labelled anti-Ly-1, anti-Ly-2, and anti-T200. Anti-T200, but not anti-Ly-1, or anti-Ly-2, was capable of impeding the attachment of labelled anti-Thy-1.2 on unfixed cells. In general, gentle fixation with paraformaldehyde did not alter these inter-relationships. The possible functional contributions of such supramolecular relationships are discussed.