Studies on the measurement of platelet-associated fibronectin, and platelet-associated IgG in malignancy and sepsis

Fibronectin (Fn.) is widely distributed in human tissue and plasma. The ability of the Reticulo-endothelial system (RES) to retain normal phagocytic activity has been directly correlated with plasma levels of Fn.It is the purpose of this study to determine the levels of Plasma Fn., platelet associated (PA) Fn. and IgG in malignancy and sepsis.PA-IgG and PA-Fn. were measured by immunoperoxidase technique.Plasma levels of Fn. were significantly decreased in malignancy and sepsis. PA-IgG and PA-Fn. levels were significantly elevated in the advanced stage of these diseases. Thus, PA-IgG and PA-Fn. levels showed increases in parallel with the decrease in plasma Fn., both of which were normalized in conjunction with the remission of these diseases.It was concluded from these findings that plasma Fn. is depleted in patients with advanced malignancy and sepsis. These diseases are almost accompanied by DIC. This may be due to the removal of fibrin aggregates from blood by the RES. These state of thrombin stimulation are suggested by the levels of increased PA-IgG and PA-Fn.