C-reactive protein 15

There are some substances in everyone's body. These substances not only play a critical role, but also help us to phagocytize cells. At the same time, they can strengthen the rational effect, eliminate pathogenic microorganisms and damage that invade the body, thereby alleviating necrosis and preventing apoptosis. This manifestation of C-reactive protein 15 still requires further examination to know, because everyone will be different when the disease occurs.

C-reactive protein (CRP) is a protein (acute protein) that rises sharply in the plasma when the body is infected or the tissue is damaged. It activates complement and strengthens the phagocytosis of macrophages to play a regulatory role, clearing the invading pathogens and damaged, necrotic, and apoptotic tissue cells.

It plays an important protective role in the body's natural immune process. Research on CRP has a history of more than 70 years. The traditional view is that CRP is a non-specific inflammatory marker, but research in the past decade has revealed that CRP is directly involved in cardiovascular diseases such as inflammation and atherosclerosis, and is the most powerful predictor and risk factor for cardiovascular disease.

Basic Introduction

C-reactive protein (CRP). The semi-quantitative precipitation test was first used, but now with the preparation of high-quality antisera, it is possible to establish a quantitative determination method with high sensitivity, high specificity and good reproducibility. CRP was the first acute phase responder protein to be recognized, and its blood concentration increases dramatically during acute trauma and infection. CRP is synthesized by liver cells.

C-reactive protein

CRP contains five polypeptide chain subunits, which are non-covalently bound to form a disc-shaped polymer. The molecular weight is 115,000-140,000. The electrophoretic distribution is in the slow γ zone and sometimes extends to the β zone. Its electrophoretic mobility is easily affected by some factors, such as calcium ions and buffer composition.

Key Features

Structural characteristics of CRP

CRP is a ring-shaped pentameric protein whose primary structure consists of five identical subunits that are bound together by non-covalent bonds. Each subunit contains a CRP ligand binding site on its surface (ligand binding requires Ca2+), and a Clq and FcTR binding site on the other side [1].

This pentameric protein has remarkable resistance to heat and protease degradation. Interleukin-6 (IL-6) is the main stimulator of CRP synthesis. The mRNA level is also affected by interleukin-1 (IL-1), corticosteroids, etc. Unlike serum protein P (SAP), another member of the pentameric protein family, which is glycosylated, CRP undergoes unknown post-translational modifications.

CRP not only binds to polysaccharides in various cells, fungi, protozoa, etc., but can also bind to lecithin and nucleic acids in the presence of calcium ions. The bound complex has an activating effect on the complement system, acting on C1q. CRP can induce immune regulation and phagocytosis of invading cells, thereby manifesting an inflammatory response.

CRP is an extremely sensitive indicator of acute phase reaction. The concentration of CRP in plasma increases rapidly and significantly in acute myocardial infarction, trauma, infection, inflammation, surgery, and tumor infiltration, and can reach 2000 times the normal level. Combined with clinical history, it helps to follow up the course of the disease. Especially in inflammatory processes, follow-up of rheumatism, systemic lupus erythematosus, leukemia, etc.