[Rabies virus study by the plaque forming system. A simplified technique]

The author describes here a simplified and economical plaque forming system for rabies virus study. It is achieved in three steps (cells preparation and infection, apply of overlay, staining). It presents more advantages than previous techniques: time as well as culture media and handling spearing, easy and durable reading. Cells prepared with di-ethyl-amino-ethyl-dextran are added to equal quantities of diluted virus (for titration) or to virus-serum mixing (for seroneutralization) and overlaid after 4 hours with a carboxymethylcellulose medium. Reading is carried out after 6 days incubation and staining with amido black. Plaques obtained are to 2-3 mm in diameter, regularly reproductible, clear and easy to read. This technique enables titration and seroneutralization and even a rabies virus cloning.