Properties of rabies vaccine freed of neuroallergenic factor from brain tissue.

Fixed rabies virus in the form of infected sheep brain suspension was freed from approx. 80% of ballast proteins, inactivated by beta-propiolactone and lyophilized. The vaccine thus obtained was devoid of neuroallergenicity when tested on guinea pigs and was highly antigenic and immunogenic.

Freeing rabies virus of the neuroallergenic factor from brain tissue.

A method of fixed rabies virus purification from infected sheep brains was proposed. It consisted of suspending the brain tissue in phosphate-buffered hypertonic (0.3 M) NaCl solution, shaking at 37 degrees C and low speed centrifugation at the same temperature.

Properties of rabies virus (MNIIVP-74 strain) adapted to Japanese quail embryo cell culture.

The Pasteur strain of fixed rabies virus was adapted to primary cell cultures of Japanese quail embryos and designated as MNIIVP-74. In the course of adaptation the virus pathogenicity for rabbits by the intracerebral route decreased considerably and the pathogenicity for rabbits and adult white mice by extraneural routes was completely lost. After inoculation of Japanese quail embryo cell cultures, a titer of the virus in the culture fluid at 4 days was 6.