Enhanced chemotaxis of monocytes in rheumatoid arthritis

The migration responsiveness to zymosan-activated serum of monocytes isolated from the blood of 19 rheumatoid arthritis (RA) patients and 19 healthy subjects was measured. The chemotaxis of RA monocytes, but not their random migration or chemokinesis, was significantly greater than that of monocytes from normal healthy subjects. To investigate whether this effect were due to soluble factors present in RA blood, the migration of monocytes from healthy subjects was assessed in the presence of sera from 28 RA patients and 21 healthy subjects. The inability of RA sera to modify the migration of normal monocytes implies that the enhanced chemotaxis of RA monocytes is attributable to the inherent property of these cells and not due to the activity of serum modifying factors.