The appearance of migration inhibition factor and a mitogen in lymph draining tuberculin reactions

Abstract

Abstract The tuberculin reaction in the skin of sheep was accompanied by greatly increased traffic of mononuclear cells through both the lesion and through regional lymph nodes, as well as the appearance of basophilic cells in the lymph. Changes in vascular permeability were also evident and two, apparently distinct, biologically active materials appeared in the lymph plasma. The first of these materials inhibited the migration of guinea pig macrophages in a conventional migration inhibition factor (MIF) test. This material was evident within a few hours; the strongest activity appeared at about 24 h. Normal lymph and serum or lymph and serum from BCG‐sensitive sheep did not contain this material in detectable amounts. The second material that appeared in the lymph increased the DNA synthesis of normal lymphocyte cultures.