An experimental rabies vaccine produced with a new BHK-21 suspension cell culture process: use of serum-free medium and perfusion-reactor system.

An experimental rabies vaccine was prepared from the BHK-21 cell line adapted to culture in suspension using bioreactors. A new serum-free medium (MDSS2) (Merten et al., Cytotechnology, 1994, 14, 47) developed for the culture of various cell lines and for the production of several biologicals, was used for cell culture and virus production. The PV-Paris/BHK-21 rabies virus strain (adapted to the BHK-21 grown in monolayer) was adapted to BHK-21 cells cultivated in suspension and in the serum-free medium. High titres of rabies virus were obtained with bioreactors equipped with a perfusion system using BHK-21 cells grown in suspension in MDSS2. Experimental vaccines were prepared and had satisfactory protective activity when tested in mice. This new and low cost technology for rabies vaccine production could be suitable for developing countries where rabies is an important health problem.