T cells accumulating in the inflamed joints of a spontaneous murine model of rheumatoid arthritis become restricted to common clonotypes during disease progression

Abstract

Although a number of studies have revealed that T cells expand clonally in the joints of patients suffering from rheumatoid arthritis (RA), the kinetics of T cell clonality in multiple joints of an individual throughout progression of the disease is not known. By employing a TCR β chain gene-specific RT-PCR and subsequent single-strand conformation polymorphism, which enables us to monitor T cell clonality, we analyzed transgenic mice (Tg) carrying the human T cell leukemia virus type I env-pX region. These mice spontaneously develop destructive progressive arthritis similar to RA as they age. In the early stage, the majority of accumulating T cell clones differed in each of four affected feet analyzed. However, in the advanced stage, many of the clones were common to all four feet. The total number of distinct clones gradually decreased as the disease progressed. When splenocytes from arthritic elder Tg were adoptively transferred into either nude mice or young Tg, the clones common to all four feet of the donor were detected again in four feet of the recipients. These findings suggest that, as arthritis progresses, the T cell clones accumulating in the arthritic joints are gradually restricted to certain common clonotypes, some of which are arthrotropic.