Translations:Vitamin B12/28/en

Serum haptocorrin binds 80-90% of circulating B₁₂, rendering it unavailable for cellular delivery by transcobalamin II. This is conjectured to be a circulating storage function. Several serious, even life-threatening diseases cause elevated serum HC, measured as abnormally high serum vitamin B₁₂, while at the same time potentially manifesting as a symptomatic vitamin deficiency because of insufficent vitamin bound to transcobalamin II which transfers the vitamin to cells.