The expansion of CD4+CD28- T cells in patients with rheumatoid arthritis

Clonal expansion of CD4(+)CD28(-) T cells is a characteristic finding in patients with rheumatoid arthritis ( RA). Expanded CD4(+) clonotypes are present in the peripheral blood, infiltrate into the joints, and persist for years. CD4(+)CD28(-) T cells are oligoclonal lymphocytes that are rare in healthy individuals but are found in high percentages in patients with chronic inflammatory diseases. The size of the peripheral blood CD4(+)CD28(-) T-cell compartment was determined in 42 patients with RA and 24 healthy subjects by two-color FACS analysis. The frequency of CD4(+)CD28(-) T cells was significantly higher in RA patients than in healthy subjects. Additionally, the number of these cells was significantly higher in patients with extra-articular manifestations and advanced joint destruction than in patients with limited joint manifestations. The results suggest that the frequency of CD4(+)CD28(-) T cells may be a marker correlating with extra-articular manifestations and joint involvement.