High-level expression of a heterologous protein in the milk of transgenic swine using the cDNA encoding human protein C

A transgenic construct consisting of the human protein C gene and the whey acidic protein gene was developed and used to generate transgenic swine expressing the chimeric protein. The results showed that transgenic swine produced human protein C in their milk at a concentration of up to one gram per liter. The expressed human protein C possessed anticoagulant activity equivalent to plasma-derived protein C. These results demonstrate that pig mammary glands support gamma-carboxylation.