Rapid recombinant protein expression in cell-free extracts from human blood

David Burgenson, Chandrasekhar Gurramkonda, Manohar Pilli, Xudong Ge, Abhay Andar, Yordan Kostov, Leah Tolosa, Govind Rao

Several groups have recently reported on the utility of cell-free expression systems to make therapeutic proteins, most of them employing CHO or E. coli cell-free extracts. Here, we propose an alternative that uses human blood derived leukocyte cell extracts for the expression of recombinant proteins. We demonstrate expression of nano luciferase (Nluc), Granulocyte-colony stimulating factor (G-CSF) and Erythropoietin (EPO) in cell-free leukocyte extracts within two hours. Human blood is readily available from donors and blood banks and leukocyte rich fractions are easy to obtain. The method described here demonstrates the ability to rapidly express recombinant proteins from human cell extracts that could provide the research community with a facile technology to make their target protein. Eventually, we envision that any recombinant protein can be produced from patient-supplied leukocytes, which can then be injected back into the patient. This approach could lead to an alternative model for personalized medicines and vaccines.