A U.S. Patent for “Seed Train Processes and Uses Thereof” was awarded to Genzyme on February 25th, 2020. The present invention is a method of producing a recombinant protein, wherein the method consists of: (a) disposing a plurality of recombinant mammalian cells into a first culture medium within a vessel to provide a first cell culture; (b) batch culturing the first cell culture to a cell density range of about 1.0.times.10.sup.6 cells/mL to about 5.0.times.10.sup.6 cells/mL; (c) disposing a volume of the first cell culture of step (b) into a second culture medium within a perfusion bioreactor to provide a second cell culture with an initial cell density… Learn More