PCT

Procalcitonin（PCT) is a hormonal free activity of calcitonin peptide peptide substances, from to the location on the chromosome 11 single copy gene, the gene by 2800 bases on the composition of containing six and five introns, relative molecular mass of about 13 x 103. Under normal metabolism, the C cells of the thyroid gland produce PCT and secrete hormone activity. After transcription in thyroid parafollicular cell rough endoplasmic reticulum translated into procalcitonin precursor proprocalcitonin, including an N-terminal 84 amino acids, active calcitonin (CT, 32 peptide) and calcitonin protein (katacalcin, 21 peptide) of three parts, respectively by the peptide -Lys-Arg-) and peptide -Gly-Lys-Lys-Arg- connection. The single sequence of nPro-CT was cut off by the endogenous polypeptide enzyme, and the PCT of 116 amino acids was generated. PCT is a hormone free activity of calcitonin peptide. The concentration of PCT in normal human blood is very low, but in bacterial infection and sepsis at elevated PCT. Since 1993 Assicot first reported early marker of PCT can be as a bacterial infection of the PCT as a novel inflammatory markers are widely applied to bacterial infection diagnosis and differential diagnosis, 2001 International Conference on sepsis sepsis diagnosis standard has the PCT as index of diagnosis.

PCT concentrations were detected in both clinical and scientific research laboratories, including colloidal gold method, ELISA method and immunoassay, etc.. All of these methods are based on the preparation of PCT specific antibodies, and the healthy human plasma is very low, at 200 pg / mL, the affinity of antibodies and other parameters are very high. So far, the antibodies used in the detection system are from foreign companies, the price is expensive. Therefore, the preparation of PCT specific monoclonal antibodies and for immunological detection of PCT with independent intellectual property rights of the key raw material, to expand its clinical application, reduce medical costs, is of great significance.

Our  team have expressed the PCT protein in the prokaryotic expression system, which was used to detect the monoclonal antibodies. At the same time, considering the protein secondary structure, antigenicity, hydrophilicity and hydrophobicity of, accessibility and flexibility, artificial synthesis of B cell epitope polypeptide and BSA cross-linked with prepared high specificity and high affinity monoclonal antibody.

Profile of PCT