Synergistic response between thymus and lymph node cells in the mixed lymphocyte culture.

Abstract

IN rodents the mixed lymphocyte culture (MLC) reaction probably represents an in vitro model of the graft versus host (GvH) response1. Thymus-dependent lymphoid cells (T cells) are thought to be responsible for both reactions2,3. Cantor and Asofsky4,5 presented evidence for the synergistic interaction of two thymus-dependent lymphocyte populations in the GvH response. In their studies one cell type (amplifier cells or T2 cells) was obtained from the peripheral circulation, the other type (precursor cell or T1 cell) was found in greatest concentration in the thymus and spleen. A mixture of thymocytes and peripheral blood lymphocytes produced a GvH reaction significantly greater than was expected from summation of the separate reactivities of the components of the mixture. This ‘synergy’ occurred only when both cell populations had been obtained from donors allogeneic to the host4.