Rhizosecretion of recombinant proteins from plant hairy roots.

Rhizosecretion of a target protein in the hydroponic medium provides an alternative manufacturing platform that simplifies the downstream purification procedure and increases protein yield. In order to increase the production rates of rhizosecreted proteins, we have exploited the ability of Agrobacterium rhizogenes to induce the formation of large amounts of root tissue on transgenic tobacco plants engineered to secrete a model recombinant protein, human secreted alkaline phosphatase (SEAP). The secretion of SEAP from hairy roots induced on the stems of transgenic tobacco plants was 5-7 times higher than that from adventitious transgenic roots.