[EA rosettes in patients with progressive chronic polyarthritis]

One subpopulation of human lymphocytes contains Fc-receptors that form rosettes with antibody (IgG) coated human erythrocytes (EA-rosettes). On the average 8.9% of the lymphocytes from patients with rheumatoid arthritis (RA) form EA-rosettes compared with 5.3% in controls. When the lymphocytes were washed three times the EA-rosettes increased to 21.2% for RA patients and 9.5% for controls. This procedure thus reveals more Fc-receptors on the lymphocytes from RA patients than on those from healthy controls. The number of T-lymphocytes was normal in RA patients and controls, no matter how many times the lymphocytes were washed.