Self- and allo-specific suppressor T cells evoked by intravenous injection of F protein.

The liver/serum protein F appears to inactivate clones reactive towards itself in the T helper cell but not the B cell compartment. To examine the extent of self-reactivity in the T suppressor cell compartment, the well-established procedure of i.v. injecting milligram doses of the protein was used. To detect suppression, an entirely in vitro proliferation assay was devised, based on use of immunopurified F antigen. In this way T suppressor cells could be detected after activation either by allogeneic F, or (though to a lesser extent) by self-F protein. Thus the T suppressor cell compartment contains potentially self-reactive clones, and to that extent the receptor repertoire of T suppressor cells overlaps with B rather than T helper cells.