Abstract
Thoracic duct lymphocytes from rats sensitized against syngeneic spinal cord rapidly produce damage in cultures of syngeneic cerebellar cells but coexist indefintely with allogeneic cultures. Lymphocytes from donors that have been sensitized against allogeneic spinal cord attack cultures of syngeneic and specific allogeneic cerebellum but not cells from rats of a third, unrelated strain.