Abstract
Biochemical and immunological investigations were made on the nature of fluorocarbon-treated antigens obtained from placenta and cancer tissues. 1) By the diffusion in gel method, a specific antigen common to cancer tissues was found in placental tissue, but not in normal tissue. Immunoelectrophoretically, a characteristic precipitate line was found in a2-globulin region. 2) Further purification of the placental antigens was carried out by DEAE-cellulose chromatography. Four fractions positive to Folin reaction were detected. 3) Immunoelectrophoresis revealed that the active component was concentrated in a fraction eluted with 0.1 M NaCl in 0.05 M phosphate buffer, pH 5.8 (5.8-fraction). 4) Further purification of the active component was performed by using polyacrylamide gel electrophoresis. Chemical analysis indicated that it belonged to glycoprotein. 5) This substance did not induce anemia in rabbits and had no influence on the osmotic fragility of erythrocytes. These results indicate that this substance is different from the anemia-inducing substance which was previously reported by us.