Characterization of human T-lymphocyte clones (TLCs) specific for HLA-region gene products.

Clones of lymphocytes, primed in vitro to HLA-DR1;Dw1, were tested for allospecific proliferation on a panel of thirty-one HLA-phenotyped stimulating cells. No clone was restimulated exclusively by cells sharing the DR1;Dw1 priming antigens and most clones were restimulated by subsets of cells bearing DR1;Dw1. Generally, positive responses were at least 20-fold higher than autologous negative controls. Peak proliferative responses occurred around 72 h and varied, depending on the stimulating cell as well as the responding clone. Selected clones were induced to proliferate only by cells incapable of forming rosettes with sheep erythrocytes. Specific proliferation by TLCs was blocked by monoclonal DR-specific antibodies, but not by monoclonal anti-Thy 1.2. Genetic studies demonstrated that TLCs detected some cell-surface determinants that are encoded by genes in linkage disequilibrium with HLA and others that may not be linked to the human major histocompatibility complex.