Human amylin, consisting of 37 amino acids, plays an important role in diabetes, Alzheimer`s disease, obesity and other diseases. However, high production costs and low biological actions have limited its application in these diseases. The mammalian mammary gland can secrete milk and act as a good bioreactor for foreign proteins. In our study, we have constructed pBC1-human-amylin breast specificity expression vector and human amylin mammary gland bioreactor mouse model by pronuclear microinjection. Polymerase Chain Reaction (PCR), relative quantification PCR and absolute quantification PCR were used to determine the expression of transgenic offspring. The expression of human amylin in mouse milk was identified by western blot and enzyme linked immunosorbent assay. Results showed that amylin can be expressed in the mouse’s mammary gland during lactation. The concentration of human amylin in transgenic mice milk was 1.44 μg/ml. An average of 4 copies of the transgenic was obtained in the first-generation mice. In the biological function experiment, we observed that human amylin in the mouse milk has biological activities and exhibits blood glucose lowering effect. Conclusively, we have successfully constructed a vector for breast-specific expression of human amylin, meanwhile, this kind of human amylin can be obtained in transgenic mouse milk which exhibits biological functions such as blood lowering effect. These results are significant in the application of human amylin in amyloidosis-related disease such as type 1 and type 2 diabetes.
Posted by: Kongwei Huang, Development of mammary gland bioreactor for human amylin, State Key Laboratory of Protection and Utilization of Subtropical Agricultural Bioresources, Guangxi University, China (23-Aug-2018)