Delivery of Vitamin B 12 to Human Lymphocytes by Transcobalamins I,II and III 1

Summary

⁵⁷Co B₁₂ bound to TC II promoted uptake by PHA-stimulated lymphocytes, while TC III and TC I bound B₁₂ had no such effect. TC III like TC I appears to be a storage protein in blood rather than a means of transferring vitamin B₁₂ selectively to hematopoietic cells.