Produkt: Vitamin D Binding Protein (VDBP) ELISA
Vitamin D Binding Protein (VDBP) ELISA
: 96 determinations
: serum, plasma, urine
: 1:40000 pre-dilution
: 100 µl
: 2.2 - 60 ng/ml
: 1 h, 1 h, 10-20 min (RT/shaking)
: TMB at 450 nm
: 1.23 ng/ml
Vitamin D-binding protein (VDB; MW = 51 243 Da, positions 17–474, 458 amino acids, P02774 VTDB_HUMAN) or Gc-globulin is a multifunctional serum protein synthesized in the liver. It is structurally related to albumin and is similar in size. The majority of vitamin D in the blood circulates bound to the VDB. Gc-globulin has been reported to be a macrophage-stimulating factor, to possess chemotaxin activity and to have endotoxin-binding capacity. Furthermore, Gc-globulin has one actin-binding site and forms 1:1 complexes with monomeric actin. Actin is an intracellular protein that can polymerise and form filaments. The mobility and the shape of cells depends on this ability.
Upon massive cell death and tissue destruction, the release of actin may lead to a significant decrease in the components of the extracellular actin scavenger system. Decreased VDB levels were found in serum samples from several patients groups at risk of developing multi-organ failure, e.g. trauma, spesis etc.
- Risk factor for traumatic injury
- Nephrotic syndrom
Principle of the test
This Enzyme Immuno Assay is a sandwich assay for VDB determination in serum, plasma and urine samples. The wells of the micro titer plate are coated with polyclonal anti-VDB antibodies. In a first incubation step, the VDB in the samples is bound to the coated polyclonal rabbit antibodies (in excess). To remove all unbound substances, a washing step is carried out. In a second incubation step, a polyclonal Peroxidase-labeled rabbit-anti-VDB antibody is added. After another washing step, to remove all unbound substances, the solid phase is incubated with the substrate, Tetramethylbenzidine. An acidic stopping solution is then added. The color converts to yellow. The intensity of the yellow color is directly proportional to the VDB concentration in the sample. A dose response curve of the absorbance (at 450 nm) unit vs. concentration is generated.