Early cellular events in a systemic graft vs. host reaction. II. Autoradiographic estimates of the frequency of donor lymphocytes which respond to each Ag B determined antigenic complex

Abstract

The frequency of nonimmune lymphocytes which can recognize the Ag B determined antigenic complex of the recipient in a graft vs host system is probably about 12% of T lymphocytes. Antigenic recognition was assessed by the sequestration of antigen sensitive cells from the traffic stream of lymphocytes recirculating through the spleen and lymph nodes of the F1 hybrid recipient. The system can be regarded as analogous to an in vitro antigen binding assay except that in this case the antigen was fixed in lymphoid tissue and the number of lymphocytes which were bound to antigen in vivo was measured. As is the case with counts of antigen binding cells in vitro it was not known how many of the cells which were scored could respond to antigen by other criteria such as cell division or the production of effector cells.