Observations on the etiologic relationship of achylia gastrica to pernicious anemia. I. The effect of the administration to patients with pernicious anemia of the contents of the normal human stomach recovered after the ingestion of beef muscle.

Castle showed pernicious anemia to be due to absence from the gastric juice of a substance (Castle’s intrinsic factor, hemopoietin) that reacts with an extrinsic factor present in many foodstuffs to form the anti-pernicious anemia factor. His experimental work resulted in the introduction of stomach preparations for the treatment of pernicious anemia. Preliminary communication in J. Clin. Invest., 1928, 6, 2.