期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2015
卷号：112
期号：5
页码：1356-1361
DOI：10.1073/pnas.1423668112
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificanceMany therapeutic proteins suffer from short plasma half-lives and, as a consequence, require frequent injections to be therapeutically effective; this in turn can adversely affect patient compliance and quality of life. In contrast, therapeutic antibodies typically have half-lives of weeks in humans. Consequently, there is considerable interest in generating functional antibodies with agonist or antagonist activities. Based on the structure of a natural bovine antibody with an ultralong, well-folded heavy-chain complementarity-determining region, we have developed a strategy for the generation of functional human antibody-hormone chimeras with biological activities comparable to native hormones and significantly enhanced pharmacological properties. This approach likely provides a general, relatively straightforward platform for generating antibody agonists and antagonists for a range of therapeutic applications. On the basis of the 3D structure of a bovine antibody with a well-folded, ultralong complementarity-determining region (CDR), we have developed a versatile approach for generating human or humanized antibody agonists with excellent pharmacological properties. Using human growth hormone (hGH) and human leptin (hLeptin) as model proteins, we have demonstrated that functional human antibody CDR fusions can be efficiently engineered by grafting the native hormones into different CDRs of the humanized antibody Herceptin. The resulting Herceptin CDR fusion proteins were expressed in good yields in mammalian cells and retain comparable in vitro biological activity to the native hormones. Pharmacological studies in rodents indicated a 20- to 100-fold increase in plasma circulating half-life for these antibody agonists and significantly extended in vivo activities in the GH-deficient rat model and leptin-deficient obese mouse model for the hGH and hLeptin antibody fusions, respectively. These results illustrate the utility of antibody CDR fusions as a general and versatile strategy for generating long-acting protein therapeutics.
