Measurement of transcobalamin by ELISA.

Characterization of a monoclonal antibody with specificity for holo-transcobalamin

BACKGROUND Holotranscobalamin, cobalamin-saturated transcobalamin, is the minor fraction of circulating cobalamin (vitamin B12), which is available for cellular uptake and hence is physiologically relevant. Currently, no method allows simple, direct quantification of holotranscobalamin. We now report on the identification and characterization of a monoclonal antibody with a unique specificity f...

Holotranscobalamin, a marker of vitamin B-12 status: analytical aspects and clinical utility12345

Approximately one-quarter of circulating cobalamin (vitamin B-12) binds to transcobalamin (holoTC) and is thereby available for the cells of the body. For this reason, holoTC is also referred to as active vitamin B-12. HoloTC was suggested as an optimal marker of early vitamin B-12 deficiency >20 y ago. This suggestion led to the development of suitable assays for measurement of the compound an...

Measurement of Epsilon Antitoxin in Sheep Sera by ELISA

First trimester serum levels of the soluble transcobalamin receptor, holo-transcobalamin, and total transcobalamin in relation to preeclampsia risk.

BACKGROUND Human placenta expresses CD320, a receptor that ensures the uptake of holo-transcobalamin (holoTC). Soluble CD320 (sCD320) is present in the circulation and its concentration increases during pregnancy. AIMS To investigate a possible association of sCD320, holoTC and total transcobalamin (TC) with the risk of subsequent preeclampsia using serum samples from asymptomatic first trime...

A new principle for measurement of cobalamin and corrinoids, used for studies of cobalamin analogs on serum haptocorrin.

BACKGROUND Transcobalamin (TC) and haptocorrin (HC) are serum corrinoid-binding proteins. We developed new methods for measurement of the corrinoids bound to HC and TC. METHODS TC (n = 10) or HC (n = 138) was immunoprecipitated, and corrinoids were released by enzymatic degradation [subtilisin Carlsberg (EC 3.4.21.62)] of the binding proteins. Binding of the released corrinoids to added unsat...