Measurement of transcobalamin by ELISA.
BACKGROUND
Transcobalamin is essential for the cellular internalization of cobalamin. Methods to quantify the unsaturated protein are available, but few attempts have been made to develop methods to quantify the sum of unsaturated and cobalamin saturated transcobalamin.


METHODS
gamma-Globulins from two polyclonal rabbit antibodies against recombinant human transcobalamin were used as capture and detection antibodies, and recombinant human transcobalamin was used as calibrator in an ELISA design.


RESULTS
The ELISA is specific for transcobalamin and has a detection limit of <1.6 pmol/L. The imprecision (CV) is 4-6% for mean concentrations of 13-70 pmol/L. The central 95% interval for serum from healthy blood donors (n = 77) was approximately 600-1500 pmol/L and showed limited variation with age and sex. No correlation was observed between the marker of acute phase reaction, C-reactive protein, and transcobalamin in plasma.


CONCLUSIONS
The ELISA measures total transcobalamin in serum and thus can be used for measurement of transcobalamin in patients treated with cobalamin.
Nexo
E
E
Department of Clinical Biochemistry, AKH, Aarhus University Hospital, Norrebrogade 44, DK-8000 Aarhus C, Denmark.
Christensen
A L
AL
Petersen
T E
TE
Fedosov
S N
SN
D000818:Animals; D000906:Antibodies; D001782:Blood Donors; D002097:C-Reactive Protein / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D011817:Rabbits; D012044:Regression Analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012737:Sex Factors; D014155:Transcobalamins / Q000032:analysis* / Q000276:immunology
D000906:Antibodies; D014155:Transcobalamins; D002097:C-Reactive Protein