Production of plasmid DNA for human gene therapy using modified alkaline cell lysis and expanded bed anion exchange chromatography

Abstract

We describe a process for the commercial manufacture of therapeutic grade plasmid DNA. The industrially scaleable unit operations employed in this process are: (i) optimized alkaline lysis; (ii) bag filtration; (iii) expanded bed anion exchange chromatography; (iv) ultrafiltration, and (v) size exclusion chromatography. These steps are scaleable alternatives to current approaches to plasmid DNA isolation such as high speed centrifugation for feed-stock clarification and solvent precipitation for plasmid concentration, and an efficient alternative to conventional low through-put packed bed chromatography. The process produces plasmid DNA characterized by low level chromosomal DNA, RNA and endotoxin contamination without the use of flammable solvents or toxic reagents and is suitable for therapeutic administration.