Rapid collection of human intrinsic factor uncontaminated with cobalophilin (R binder).

Intrinsic factor and R binder cobalamin binding capacity (CblBC) were measured in gastric juices obtained through feeding gastrostomy tubes (FG-GJ) from six patients with relatively complete obstruction to swallowing because of surgical resections for oropharyngeal or laryngeal carcinomas. Controls were six nonpernicious anemia gastric juices. In five of the six FG-GJ 97% of CblBC was intrinsic factor. In the sixth FG-GJ, with GJ pH = 7.2, in addition to intrinsic factor there was 22% nonintrinsic factor cobalamin-specific binder, which presumably represented partially degraded R binder refluxed from the duodenum. These data demonstrate that relatively "pure" intrinsic factor, i.e., uncontaminated with other cobalamin binders, can easily be obtained by simple drainage of FG-GJ. The study also supports evidence that gastric juice R binder is either swallowed or refluxed from the duodenum, and does not originate in the stomach.