Calcium phosphate flocculation of antibody-producing mammalian cells at Pilot scale

BIOT 80

Russell Shpritzer, Steven Vicik, Scott Orlando, Hari Acharya, and Jonathan L. Coffman. Process and Product Development, Wyeth BioPharma, 1 Burtt Road, Andover, MA 01810
Removal of cellular debris present in mammalian cell conditioned media has become increasingly difficult due to high cell density, low viability, and extended cell culture duration. A method of flocculation is described that entails the addition of calcium chloride and potassium phosphate to the cell-containing medium, resulting in a precipitated solid that associates with debris and facilitates its removal by centrifugation.

After development at the lab-scale, the method was tested at pilot-scale in several antibody processes. The turbidity in the centrate was significantly reduced with recovery of antibody typically greater than 90%. The flocculation of the cell-containing conditioned media decreased the particulate burden on the subsequent filtration train, decreased the precipitation of the Protein A peak, and, in some cases, increased the removal of host cell proteins.