The effect of sympathetic nervous system (SNS) axotomy on the immune response will be assessed with emphasis on T suppressor cell function in mice. Mice will be axotomized with 6-hydroxy dopamine. Response of spleen cells to lectins including con A, PWM and LPS will be determined over time taking advantage of flow cytometry to follow cells through the cell cycle. Preliminary data indicate augmented con A response after axotomy. Binding of neurotransmitter agonists to lymphocytes will be measured since loss of SNS function could derange receptor density on lymphocyte subsets. Monoclonal antibodies specific for lymphocytes will be used to enumerate cells seeking evidence for depletion or increase in number of subset cells. Experimental allergic encephalomyelitis will be studied as a prototype autoimmune disease in axotomized mice. It is postulated that "stress" modulates immune response and predisposes to autoimmunity. The vector of this stress related response may be via the SNS.