The cytotoxic activity of mononuclear cells from joint fluid

Abstract

The mononuclear cells from the joint fluid of certain patients with inflammatory arthritis are shown to be more cytotoxic to a polyploid strain of homologous liver cells than were equivalent numbers of peripheral blood lymphocytes from the same donors. The diagnostic categories of these patients are essentially similar to those of a group of patients studied by Hedberg (1967) in whom joint fluid mononuclear cells were cytotoxic to monolayers of human foetal fibroblasts. Evidence is presented to show that this cytotoxic activity is attributable to lymphocytes, as opposed to polymorphonuclear leucocytes or phagocytic mononuclear cells which adhere to glass. It is not excluded that the latter population may also have some cytotoxic potential. It is argued that the target cell damage described in this paper is probably not induced by any antigen on the target cell. The implications of this suggestion are discussed in relation to the pathogenesis of inflammatory joint disease.