A multienzyme complex in serum of hepatic cancer.

alkaline phosphatase closely resembled that extracted from microsomes of human liver in some physicochemical respects. The specific activities of these enzymes in the complex were found to be of similar order of magnitude as compared with those of the same enzymes in plasma membranes isolated from the human liver. From the precipitate formed by incubating the complex with its antibody, all the enzyme activities originally present in the complex were well recovered. Antibody against the plasma membranes of the human liver demonstrated a single precipitin line against the enzyme complex, indicating that the plasma membrane and the complex share one or several antigenic determinants.