GH Human 20kDa

The 20kDa variant of human growth hormone is a single, non-glycosylated polypeptide chain consisting of 177 amino acids, with a molecular mass of approximately 20,322 Daltons . It is produced in Escherichia coli (E. coli) and purified using proprietary chromatographic techniques .

Human growth hormone belongs to the somatotropin/prolactin family of hormones. The gene encoding this hormone is located on chromosome 17, along with four other related genes. These genes share a high degree of sequence identity and are thought to have evolved through gene duplications . The 20kDa variant is expressed in the pituitary gland but not in placental tissue, unlike some other members of this gene family .

The recombinant 20kDa human growth hormone is produced in E. coli using a modified signal peptide from Staphylococcus aureus to facilitate secretion into the extracellular medium . This method ensures the production of an active form of the hormone, free from endotoxins . The hormone is then purified to a high degree of purity (>98%) using techniques such as size-exclusion chromatography (SEC-HPLC) and SDS-PAGE .

The lyophilized form of the 20kDa growth hormone is stable at room temperature for up to three weeks but should be stored desiccated below -18°C for long-term storage . Upon reconstitution and filter sterilization, it can be stored at 4°C for up to four weeks. For more diluted solutions, adding a carrier protein such as human serum albumin (HSA) or bovine serum albumin (BSA) is recommended to prevent freeze-thaw cycles .

Human growth hormone is essential for normal growth and development. Deficiencies in this hormone can lead to growth disorders and short stature. Recombinant human growth hormone, including the 20kDa variant, is used in the treatment of growth hormone deficiencies and other related conditions . The production of recombinant hGH in suitable hosts like E. coli provides a cost-effective and efficient method for obtaining this therapeutic protein .

Studies have shown that the 20kDa variant of human growth hormone has significant metabolic effects in patients with growth hormone deficiency. It has been administered in various doses to evaluate its efficacy and safety . These studies help in understanding the therapeutic potential of this recombinant hormone in clinical settings.