Human growth hormone（hGH）, a classic therapeutic protein, which promotes growth and wound healing, is released from the pituitary gland. As a protein drug, its short half-life is its main barrier to therapeutic effi...Human growth hormone（hGH）, a classic therapeutic protein, which promotes growth and wound healing, is released from the pituitary gland. As a protein drug, its short half-life is its main barrier to therapeutic efficacy. Various strategies have been designed to prolong its serum half-life, the most conunon of which is the conjugation with polyethylene glycol（PEG）, as this has been shown to significantly extend protein＇s serum half-life. However, PEGylation often results in random conjugation, which can lead to impaired protein function and hinder purification, characterization and evaluation of the PEGylated protein. Therefore, site specific PEGylation is a promising direction for PEG-protein conjugation. Here we took advantages of the mutated sortase A（7M） enzyme, which can enzymati- cally ligate the universal a-amino acids to a C-terminal tagged protein. This then allows specific modification of the C-terminal of hGH with PEG. This site-specific bound PEG-hGH has similar efficacy, receptor binding and cell proliferation as wild-type hGH; however, pharmacokinetic analysis demonstrates that its serum half-life is almost 24 times that of wild-type hGH. Herein, we provided a promising advancement in the development of site specific PEGylated therapeutic proteins.展开更多
基金Supported by the Projects of Science ＆ Technology of Jilin Province, China（No.20150204030YY）, the Project of the Research and Development of Industrial Technology of Jilin Province, China（No.2015Y058） and the National Natural Science Foundation of China（No. 51402286 ）.
文摘Human growth hormone（hGH）, a classic therapeutic protein, which promotes growth and wound healing, is released from the pituitary gland. As a protein drug, its short half-life is its main barrier to therapeutic efficacy. Various strategies have been designed to prolong its serum half-life, the most conunon of which is the conjugation with polyethylene glycol（PEG）, as this has been shown to significantly extend protein＇s serum half-life. However, PEGylation often results in random conjugation, which can lead to impaired protein function and hinder purification, characterization and evaluation of the PEGylated protein. Therefore, site specific PEGylation is a promising direction for PEG-protein conjugation. Here we took advantages of the mutated sortase A（7M） enzyme, which can enzymati- cally ligate the universal a-amino acids to a C-terminal tagged protein. This then allows specific modification of the C-terminal of hGH with PEG. This site-specific bound PEG-hGH has similar efficacy, receptor binding and cell proliferation as wild-type hGH; however, pharmacokinetic analysis demonstrates that its serum half-life is almost 24 times that of wild-type hGH. Herein, we provided a promising advancement in the development of site specific PEGylated therapeutic proteins.
