Fibronectin receptor on polymorphonuclear leukocytes in families of Ehlers-Danlos syndrome and other hereditary connective tissue diseases.

Studies were made on the fibronectin receptor on polymorphonuclear leukocytes of patients with hereditary connective tissue diseases and of healthy members of their families. In four patients with Ehlers-Danlos syndrome type II (family E) and type VI (family M), the maximum number of binding sites (Bmax) of fibronectin receptor was significantly decreased to 2.2 to 2.9 x 10(3) sites/cell (normal range 6.3 +/- 1.5 x 10(3) sites/cell). The Bmax values of healthy members of their families were normal or moderately decreased to 3.8 to 5.1 x 10(3) sites/cell. In a patient with osteogenesis imperfecta type III (family K) the Bmax was significantly decreased to 1.1 x 10(3) sites/cell, but healthy members of his family had normal Bmax values. In a patient with Marfan syndrome (family A) the Bmax was decreased to 4.3 x 10(3) sites/cell. The dissociation constant of the fibronectin receptor was normal in all subjects examined. Some healthy members of the families of the patients with Ehlers-Danlos syndrome had moderately decreased Bmax values, suggesting that they are carriers of an abnormal gene causing this disorder. These data suggest that fibronectin receptor is closely related to the pathogenesis of hereditary connective tissue diseases.