Fibronectin and cryoprecipitation.

Fourteen patients with essential mixed cryoglobulinemia were studied. The relevance of fibronectin (FN) in cryoprecipitation seems to be of relative importance since only two thirds of the cryoprecipitates have a higher cryocrit level when FN is present. On the other hand, the other samples show a lower precipitating activity after plasma heating at 60 degrees C. This reduction may reflect either a structural FN modification by heating or the denaturation of other cryoprecipitating molecules. It is possible, even if not necessary, that at least in vitro FN plays a role in the cryoprecipitate formation.