Binding of purified, soluble major histocompatibility complex polypeptide chains onto isolated T-cell receptors. I. Reactivity against allo- and self-determinants.

Abstract

The fine antigen-binding ability of purified, soluble, idiotype-positive T [thymus-derived] cell receptor molecules was studied in rats. Lewis anti-DA T cell receptors were purified from normal Lewis serum by the use of anti-idiotypic immunosorbent and sodium dodecyl sulfate-polyacrylamide gel and were coupled to CNBr activated Sepharose 4B. Lewis anti-DA, Lewis anti-BN and DA anti-Lewis alloantibody immunosorbents were also prepared. The major Ag-B chain (44,000 daltons) and the 2 polypeptide chains (34,000 and 27,000 daltons) of Ia were purified from Lewis, DA and BN lymphocytes and absorbent on the above-mentioned immunosorbents. The major Ag-B chain and the 2 Ia chains were bound to the alloantibody columns if they were derived from the corresponding allogeneic strain. No retaining ability for self-major histocompatibility complex (MHC) or 3rd-party MHC chains was noted with the alloantibody immunosorbents. When using immunosorbents made up of idiotypic T cell receptors, only 2 MHC polypeptides of the relevant allo-MHC type were retained, i.e., the Ag-B and the H Ia chains. No detectable activity was observed when testing the same column for reactivity against 3rd-party MHC polypeptide chains. The Lewis anti-DA T cell receptors displayed weak but significant reactivity toward 1 Lewis MHC polypeptide chain, i.e., the H chain of Ia type.