Studies on the Pathogenesis of Rheumatoid Joint Inflammation

Abstract

A hypothesis has previously been presented that rheumatoid joint inflammation results from the phagocytosis of intra-articular complexes of rhemuatoid factor and 7S gamma globulin by leukocytes. To test this hypothesis, autologous purified 7S gamma globulin was injected into the uninvolved knees of rheumatoid patients known to harbor the rheumatoid factor and resulted in acute arthritis in 5 of 6 instances. Purified rheumatoid 7S gamma globulin injected into 3 homologous rheumatoid arthritic and 5 osteoarthritic knees produced no reaction. Intraarticular injection of non-rheumatoid 7S gamma globulin produced joint inflammation in only 1 of 7 trials in rheumatoid patients. These preliminary data tend to support the above hypothesis, and allow speculation that 1 of the steps in the pathogenesis of rheumatoid inflammation might be the alteration of the 7S gamma globulin molecule in such a way that it becomes specifically antigenic.