Blood monocyte elastolytic activity enhanced by immune complex stimulation in patients with rheumatoid arthritis and...

Blood monocyte elastolytic activity in patients with rheumatoid arthritis and in normal controls was studied by a new in vitro technique. The enzyme activity of live cells was measured by soluble [3H]elastin hydrolysis first under basic conditions and then after immune complex stimulation. The cells from patients had a higher elastolytic potential than cells from controls (p less than 0.02) and responded to smaller amounts of immune complex (p less than 0.01), even in patients treated with D-penicillamine or aurothiomalate. Treatment of normal monocytes in vitro with aurothiomalate did not influence the elastolytic response. These findings indicate that monocytes from patients with rheumatoid arthritis have an enhanced elastolytic activity compared with cells from normal controls and may invoke greater tissue damage on immune complex stimulation.