Plasma or serum from patients with systemic sclerosis alters behaviour of normal erythrocytes.

Incubation of washed normal erythrocytes with fresh or frozen plasma or serum from patients with systemic sclerosis (SS) significantly decreased the filterability of the cells, whereas the incubation of homologous normal serum or plasma with washed erythrocytes did not alter the filterability of these cells. The endothelial cell adherence of normal erythrocytes was increased by 3.5- and 2.6-fold (p less than 0.01) respectively when plasma or serum from patients with SS rather than that from normal controls was added to the incubation medium. Further investigation and isolation of the reactive material(s) present in the serum and plasma of patients with SS, which affect the deformability and endothelial cell adherence of erythrocytes, may be helpful in understanding the pathogenesis of the disease.