Con A induced suppressor test: an evaluation of the experimental conditions.

The suppressor activity measured by the Con A mixed lymphocyte culture assay exhibited a pronounced dependence on the technical performance as well as a marked inter-individual variation. The activity exerted by the induced suppressor cells depended on the Con A concentration in the induction phase, and on the mitotic activity in the responder system. The patterns of suppressor activities obtained in an allogeneic and an autologous suppressor test system were identical. When calculating the suppressor activity it is suggested, that one uses the total activities of the test system, without any reduction corresponding to the activity of the mixed lymphocyte culture. It is suggested that the suppressor activity is expressed by a "suppressor profile" to make the results more applicable and the interpretation of different works meaningful.