Provided is a cell therapeutic agent for treating an inflammatory disease induced by a hyperimmune response, more specifically, a composition for treating an inflammatory disease induced by a hyperimmune response, which comprises (i) a chondrocyte or a cell capable of differentiating into a chondrocyte and (ii) a chondrocyte into which a gene encoding TGF-β is introduced or a cell capable of differentiating into a chondrocyte into which a gene encoding TGF-β is introduced.
