title: The preparation of human intrinsic factor-cobalamin complex from human gastric juice by immunoadsorption.
abstract: Immune complexes of human intrinsic factor were prepared by mixing gastric juice saturated with vitamin B12, and sera from patients with pernicious anaemia that had a high proportion of binding (Type II) antibody. The complexes were isolated by sodium sulphate precipitation followed by Sephadex G-150 gel filtration. Acid conditions dissociated the immune complexes and allowed separation of specific antibody and purified antigen bound to vitamin B12 by Sephadex G-200 gel filtration. Specific antibody was covalently attached to Protein A Sepharose CL-4B by coupling with water soluble carbodiimide which allowed intrinsic factor-B12 complex to be purified directly from gastric juice. The intrinsic factor obtained after iodination, ran as a single band on SDS-polyacrylamide gel electrophoresis and was biologically active.
mesh_terms: D000752:Anemia, Pernicious / Q000276:immunology; D000818:Animals; D000936:Antigen-Antibody Complex / Q000302:isolation & purification; D001681:Biological Assay; D005260:Female; D005750:Gastric Juice / Q000032:analysis*; D006168:Guinea Pigs; D006801:Humans; D007163:Immunosorbent Techniques; D007437:Intrinsic Factor / Q000276:immunology / Q000302:isolation & purification*; D014805:Vitamin B 12 / Q000276:immunology / Q000302:isolation & purification*
chemical_list: D000936:Antigen-Antibody Complex; C036746:intrinsic factor-vitamin B 12 complex; D007437:Intrinsic Factor; D014805:Vitamin B 12