Abstract
All adjuvant-induced arthritis has been passively transferred in a highly inbred strain of rats by transfer of viable lymph node or spleen cells, but not thymus cells, to normal recipients. After an interval averaging 4.3 days recipients developed arthritis, whereas animals actively sensitized with adjuvant never developed disease before the 9th day (average 11.3 days). The transferred disease had all of the gross and pathological characteristics of primary disease, except for a lesser severity. Control studies using non-viable cells either of lymphoidal or other tissue origin were always negative. It is concluded that adjuvant arthritis is the result of an immunologic reaction which is perhaps similar to delayed hypersensitivity. The antigen in this reaction so far remains obscure.