Dr. Nikolov, Biological and Agricultural Engineering (BAEN) Professor and National Center for Therapeutics Manufacturing (NCTM) Director, and his graduate students, Emma Foster and Laura Soto, have been collaborating with NCTM scientists to develop an optimal production and purification process for making two recombinant versions of the COVID-19 spike protein. Laura and Emma have been working since April 2020 on the development of a reliable purification process for spike proteins. The preliminary data suggest that making 50 mg of purified protein per liter of cell culture is possible with the shorter version of the spike protein, known as the receptor-binding domain (RBD), but not that easy with the full-size spike protein.

The purified spike proteins are important for developing assays to screen donors for convalescent plasma therapy and determine the strength of antibodies present in sera of recovered COVID-19 patients. Antibodies made against the spike protein are expected to prevent the virus from binding to and infecting human cells. The production process is outlined in the illustration below.

The National Institute for Innovation in Manufacturing Biopharmaceuticals (NIIMBL) funded the NCTM project “Emergency Production of COVID-19 Spike Protein for Therapeutic Antibodies and Diagnostics” in July 2020. Dr. Nikolov, who leads this project, is excited to scale-up the spike protein production and deliver hundreds of milligrams of -purified protein to collaborators at the Army Research Lab-South and Houston Methodist Hospital, the U.S. Department of Commerce’s National Institute of Standards and Technology, and NIIMBL.

A purified COVID-19 spike.