[Stimulation and suppression of contact dermatitis in mice with a low-molecular thymic humoral factor].

The authors studied the influence of the low molecular lymphocyte-stimulating substance (LSS) of the thymus on the development of contact sensitivity to picrylchloride in mice. As revealed, low LSS doses enhanced, and high doses suppressed this type of delayed hypersensitivity. Contact sensitivity was passively transfered by means of the lymph node and spleen cells isolated on the 6th day after the immunization. Experiments showed mice given high LSS doses to contain cells suppressing passive transfer of contact sensitivity by immune cells. This suppression was annulled after the treatment of cells with theta-antiserum and the complement. A conclusion was drawn that suppressor cells influenced the effector phase of contact sensitivity.