Suppression of contact sensitivity to picryl chloride. Interaction between T suppressor auxiliary cells, suppressor factors and macrophages.

Immunization with picryl chloride generates cyclophosphamide resistant T immune cells (TDH) as well as cyclophosphamide sensitive T suppressor auxiliary cells (Ts-aux). T suppressor efferent cells do not inhibit effector phase of contact sensitivity in the absence of Ts-aux. These cells as well as macrophages adsorb TNP--T suppressor factor (TNP-TSF) and on these "armed" cells suppression may be transferred into recipients. Interactions between T-suppressor cells, their factors, Ts-auxiliary cells and macrophages are discussed.