INTRINSIC FACTOR

The Intrinsic Factor which is formed in the stomach is essential for the absorption of vitamin B12 taken with the food which takes place under physiological conditions in the ileum. It belongs to the group of glycoproteins. The electronegative carbohydrate group-here particularly the acylneuramic acids-protect the protein structures which are specific for the biological effect against the attack of tryptic enzymes in the gastrointestinal tract. If cells of the gastric mucosa degenerate, the glycoprotein may enter the circulation and thus is may trigger the formation of circulating antibodies to the Intrinsic Factor and to cells from the mucosa. This may be of decisive importance for the pathogenesis of pernicious anemia which is due to an Intrinsic Factor deficiency. © 1969 J. F. Lehmanns Verlag.