[Leukocyte and erythrocyte interaction with collagen in vitro: scanning electron microscopy study]

Scanning microscopic investigations show the interaction of Leukocytes and Erythrocytes with fibrillar and aggregating type I and type III collagens in vitro. Leukocytes, in the presence of collagen, form loose aggregates within a minute and these aggregates, after 15 to 30 minutes, coalesce and become compact. The close association of the fibrillar collagens to the leukocyte surfaces is shown. Fibrillar collagen and collagen in solution with erythrocytes form only loose aggregates. Qualitative differences between the various collagen preparations were not found. The pathogenetic implications of these observations are briefly discussed.