Lipopolysacharide (LPS) Binding Protein (LBP) is a type 1 acute phase protein that is constitutively produced by the liver and rapidly upregulated during the acute phase response.
LBP plays a central role in the response to LPS. The protein catalyzes the monomerization of LPS and its transfer to (s)CD14 and to lipoproteins. This way LBP has both a role in the activation pathway of LPS: activation of monocytes by LPS leading to release of inflammatory mediators and in the neutralization of LPS i.e. the uptake of LPS by lipoprotein and subsequent clearing. In plasma of healthy individuals LBP is present at levels of approximately 10 µg/ml, which increase approximately 10-fold during acute phase responses.
Application
The human LBP ELISA kit is to be used for the in vitro quantitative determination of human LBP in serum, plasma and cell culture supernatant samples.
Principle
The human LBP ELISA is a ready-to-use solid-phase enzyme-linked immunosorbent assay based on the sandwich principle with a working time of 3½ hours. The efficient format of a plate with twelve disposable 8-well strips allows free choice of batch size for the assay. Samples and standards are captured by a solid bound specific antibody. Biotinylated tracer antibody will bind to captured human LBP. Streptavidin-peroxidase conjugate will bind to the biotinylated tracer antibody. Streptavidin-peroxidase conjugate will react with the substrate, tetramethylbenzidine (TMB). The enzyme reaction is stopped by the addition of oxalix acid. The absorbance at 450 nm is measured with a spectrophotometer. A standard curve is obtained by plotting the absorbance (linear) versus the corresponding concentrations of the human LBP standards (log). The human LBP concentration of samples, which are run concurrently with the standards, can be determined from the standard curve.