Description(s):
C-reactive protein (CRP) is a protein produced in the liver that is found in blood plasma. Its physiologic role is to bind and opsonize apoptotic cells and certain types of bacteria by activating the complement system through C1q. This protein is clinically significant because its circulating concentration increases in response to inflammation. CRP levels rise in the serum within 24 to 48 hours following acute tissue damage and reach a peak during the acute stage. It typically decreases following the resolution of the inflammation or trauma, although the concentration increase of CRP in human serum may last for several days before returning to normal levels.
Principle
The wells of the plate are coated with capture antibody specific to CRP. In this assay, the test sample initially reacts with the solid phase capture antibody, resulting in CRP being bound to the well. The wells are then washed to remove unbound proteins, and biotin-linked antibodies are added to bind to the immobilized CRP. After washing away the unbound antibodies, Streptavidin-HRP conjugate is added to form a complex with the antibody-bound CRP. After incubation, the wells are washed to remove unbound Streptavidin-HRP conjugate. TMB substrate is then added and forms a blue color when the HRP-linked antibodies are detected. The reaction is then terminated with Stop Solution, which changes the color from blue to yellow. The CRP concentration in each well is directly proportional to its color intensity and can be quantified by measuring its optical density at 450 nm (OD450) in a microplate reader.
