Classification of Peptides

1 Cytokine mimetic peptide
The use of known cytokine receptors to screen cytokine mimetic peptides from peptide libraries has become a hot research topic both domestically and internationally in recent years. Several growth factor mimetic peptides, such as human erythropoietin, human thrombopoietin, human growth hormone, human nerve growth factor, and interleukin, have been screened abroad. The amino acid sequences of these mimetic peptides are different from those of their corresponding cytokines, but they have cytokine activity and the advantage of small molecular weight. These cytokine mimetic peptides are currently in the preclinical or clinical research stage.
2. Antibacterial active peptides
When insects are stimulated by the external environment, they produce a large amount of cationic peptides with antibacterial activity. Over a hundred antimicrobial peptides have been screened, and in vivo and in vitro experiments have confirmed that multiple antimicrobial peptides not only have strong bactericidal ability but also kill tumor cells. For example, antimicrobial peptide D screened from silkworms has shown promising application prospects and can be produced using genetic engineering technology. There are also various active peptides in snake venom. A small peptide of 13 amino acids was isolated from snake venom, which has bactericidal ability against both G+and G - bacteria.
3. Peptides used for cardiovascular diseases
Many plant-based traditional Chinese medicines have the effects of lowering blood pressure, blood lipids, and blood clots, and can be used not only as drugs but also as health foods. However, due to the uncertainty of its functional components, its application is greatly limited. It has been discovered that many effective ingredients are small molecule peptides, such as the active peptides isolated by Chinese scientists from soybean processing. They can be directly absorbed through the small intestine, prevent and treat thrombosis, hypertension, and hyperlipidemia, delay aging, and improve the body's anti-tumor ability. Many small peptides for cardiovascular diseases have also been isolated from plants such as ginseng, tea, and ginkgo leaves.
4. Other medicinal peptides
Besides making significant progress in the aforementioned areas, small peptide drugs have also made some progress in many other fields. For example, Stiernberg et al. found that a synthetic peptide (TP508) can promote the regeneration of wound blood vessels and accelerate the healing of deep skin wounds. Pfister et al. found that a small peptide can prevent alkaline damage to the infiltration of inflammatory cells in the cornea and inhibit the inflammatory response. Carron et al. confirmed that the two synthetic peptides they screened can inhibit osteoclast resorption of bone.
5. Diagnostic peptides
The main use of peptides in diagnostic reagents is for antigen detection of viruses, cells, mycoplasma, spirochetes and other microorganisms, as well as antibodies against parasites such as cysticercosis and trypanosomes. Peptide antigens have stronger specificity than natural microbial or parasite protein antigens and are easy to prepare. Therefore, the prepared detection reagents have low false negative rates and background reactions for detecting antibodies, making them easy for clinical application. Antibody detection reagents assembled with polypeptide antigens include: A, B, C, G or hepatitis virus, AIDS virus, human cytomegalovirus, herpes simplex virus, rubella virus, syphilis spirochete, cysticercosis, trypanosoma, Lyme disease and rheumatoid arthritis. Most of the peptide antigens used are obtained through analysis and screening of natural proteins from corresponding pathogenic bodies, while some are newly screened small peptides from peptide libraries.