Vitamin B12-binding proteins in human gastric mucosa. General pattern and demonstration of intrinsic factor isoproteins typical of mucosa

Scand J Clin Lab Invest. 1975 Jan;35(1):5-11. doi: 10.1080/00365517509067998.


Extracts of human stomach mucosa were shown to contain immunoreactive intrinsic factor and small amounts of R protein and transcobalamin II. In gel filtration the mucosal vitamin B12-intrinsic factor complex behaved as though its molecular weight were smaller than the corresponding complex in gastric juice. In isoelectric focusing both the gastric juice and mucosal vitamin B12-intrinsic factor complexes resolved into numerous isoproteins. These findings were verified by DEAE-cellulose chromatography. The mucosal intrinsic factor isoprotein pattern contained, in addition to the isoproteins found in gastric juice, components with higher isoelectric points -- that is, pH 5.73-6.64.

MeSH terms

  • Blood Proteins
  • Centrifugation, Density Gradient
  • Chromatography, DEAE-Cellulose
  • Gastric Juice / analysis
  • Gastric Mucosa / analysis*
  • Humans
  • Hydrogen-Ion Concentration
  • Intrinsic Factor / analysis*
  • Isoelectric Focusing
  • Proteins / analysis*
  • Transcobalamins / analysis
  • Vitamin B 12 / analysis*


  • Blood Proteins
  • Proteins
  • Transcobalamins
  • Intrinsic Factor
  • Vitamin B 12