Increased retraction of fibrin clots by endothelial cells of infants of diabetic mothers.

Cultured endothelial cells (EC) from the umbilical veins of infants of non-diabetic mothers induced retraction of fibrin clots formed by addition of thrombin to cell-free plasma. Fibrin clot retraction activity increased with time, reaching a maximum within 24 hours and was inhibited at 4 degrees C or in the presence of EDTA. This retraction had many characteristics in common with that induced by platelets. EC obtained from the umbilical veins of infants of poorly controlled insulin dependent diabetic mothers (IDDM) showed similar patterns of retraction. However, compared to normals, these cells induced greater retraction. Since the retraction of fibrin clots is thought to promote the exposure of sub-endothelial layers and since such an exposure plays a major role in thrombogenesis, we suggest that retraction of fibrin clot by EC should be taken into account in evaluating pre-thrombotic states.