Evaluation of serum- and animal protein-free media for the production of infectious bronchitis virus (M41) strain in a continuous cell line.

Infectious bronchitis virus (IBV) is produced in vitro using specific pathogen free chicken embryos, primary chicken kidney cells (CKC) and/or tracheal organ culture (TOC). Regulatory authorities in Europe (EMEA) and in the United States (FDA) have encouraged biological manufactures to reduce or eliminate the use of live animals and/or products of animal origin in biological manufacturing processes. In this paper, a stable chicken embryo-related (CER) cell line was adapted and maintained in serum free (SF) or animal protein free (APF) medium after a direct switch of the medium. The most suitable media were Ex Cell 520 and Ex Cell 302. CER monolayers adapted to SF or APF were infected with IBV (M41 strain) in agitated suspended culture and the IBV titre obtained 48 h post infection was 2.8 x 104 PFU/ml in both cases. Thus, propagation of CER cells and culture of IBV can be performed without the use of animal serum or animal protein.