The Human C-Reactive Protein (CRP) ELISA Kit is designed for the quantitative detection and measurement of CRP in serum. CRP is primarily synthesized in the liver in response to proinflammatory cytokines such as interleukin 1 (IL-1), interleukin 6 (IL-6), and tumor necrosis factor (TNF). CRP plays a key role in the recognition and removal of pathogenic microorganisms, cellular debris, and apoptotic cells. It binds to phosphocholine on bacteria, as well as several nuclear components including chromatin, histones, and snRNPs. This activates the complement system and enhances phagocytosis in macrophages. Expression of CRP is elevated in inflammatory conditions such as rheumatoid arthritis, cardiovascular diseases, and infection. It is also used as a clinical marker of inflammation for the prediction of cardiovascular diseases in asymptomatic individuals.

The assay is based on a sandwich ELISA method, in which samples are added to ELISA strip plates pre-coated with capture antibodies specific for human CRP. The captured CRP is detected by the addition of a horseradish peroxidase (HRP)-conjugated detection antibody. The addition of the chromogenic enzyme substrate 3,3’5,5’ tetramethylbenzidine (TMB) results in a colored product with an intensity directly proportional to the concentration of human CRP in the sample.