Sites of formation of the serum proteins transferrin and hemopexin.

Sites of synthesis of hemopexin and transferrin were determined by culturing various tissues of rabbits and monkeys in the presence of labeled amino acids. Labeling of the serum proteins was examined by means of autoradiographs of immunoelectrophoretic patterns as well as by precipitation in the test tubes employing immunospecific antisera. Good correlation was seen between the results obtained by the two different methods. The liver was found to be the only site of many tissues studied that synthesized hemopexin. Transferrin production was observed in the liver, submaxillary gland, lactating mammary gland, testis, and ovary.