Abstract
The purified intrinsic factor (IF) materials obtained from normal human gastric juice by a sequential column chromatography using Sephadex G-100 gel, DEAE-cellulose and Sephadex G-50 gel, were further analysed immunologically for evaluating the purity by immunodiffusion and immunoelectrophoresis techniques combined with autoradiography. The antisera were produced after successive injections of the purified materials with Freund's complete adjuvant. Purification was proved successful by these methods. IF was not detected in the gastric juice from pernicious anemia patients. Other human body fluids and tissues, such as saliva, bile, sera and liver homogenates, were shown to have no IF. Peptic and α-chymotryptic digestions destroyed the B12 binding capacity of human gastric IF, but the effect of tryptic digestion was not marked, when tested by radioimmunodifusion. The significance of this immunological technique was discussed.