[Decreased effectiveness of cold-induced heparin precipitation of plasma fibronectin in infection].

Plasma fibronectin (FN) is one of the major blood opsonins. The content of the glycoprotein reduces in sepsis which in turn may aggravate the course of the infection. FN is detectable in the content of cryoglobulins and cryofibrinogen. The formation of the heparin precipitate following plasma incubation in the cold in the presence of heparin is determined by FN involvement. Fibrinogen (FG) is another main component of the heparin precipitate. To determine the functional activity of plasma FN in sepsis and other pathological conditions, a study was made of the ability of FN and FG to go into the precipitate formed in blood plasma in the cold after its incubation with heparin. Unlike normal subjects in whom over 80% of FN on the average and about 20% of FG went into the heparin precipitate, in patients with hemoblastoses and aplastic anemia complicated by sepsis, less than 40% of FN on the average and about 7% of FG went into the precipitate. In some patients with sepsis, the heparin precipitate did not form. The reduction of FN ability to go into the heparin precipitate correlated with the gravity of the patients' condition. In uncomplicated hemoblastoses, cryoglobulinemia and cryofibrinogenemia and in immunocomplex pathology, the consumption of FN and FG during heparin precipitate formation did not significantly differ from the control. The data indicate that sepsis patients with blood system pathology may develop not only quantitative FN deficiency in the blood but also disorder of the functional activity of the opsonin.