[Immunogenicity of the avirulent strain RV194-2 of the rabies virus in mice]. / Imunogenicidade da cepa avirulenta RV194-2 do vírus rábico em camundongos.

RV194-2 rabies virus, an avirulent mutant of CVS strain, induces an inapparent infection limited to the central nervous system (CNS) in adult mice inoculated intracerebrally. This fact suggest that immune response of the host is able to eliminate the virus in CNS. For this reason, we have studied the induction of interferon and the humoral immune responses in BALB/c mice after RV194-2 inoculation. These mice presented high levels of interferon in the plasma and in the brain, with elevated levels of neutralizing antirabies antibodies. The 2-5A synthetase, an enzyme marker of interferon action, was analyzed in the brain of inoculated animals. Its enhancement in parallel to the interferon production in the brain, showed biochemical evidence that this interferon is active. Forty five days after RV194-2 virus inoculation, mice were protected against a challenge with the CVS virulent strain. The results presented herein show that RV194-2 strain has a high level of immunogenicity.

Serological evidence of rotavirus infection in a guinea pig colony.

Antibodies reacting with simian rotavirus SA11 were detected by enzyme immunoassay (EIA) and Western blot assay (WBA) in sera from guinea pigs bred for experimental use at the Fundação Oswaldo Cruz, Rio de Janeiro, Brazil. The proportion of antibody-positive animals and the antibody titres rose sharply in 1985, were maintained at a high levels in 1986 and declined in 1987. There were no obvious signs of disease coinciding with serological evidence of infection. Results of WBA suggest that the virus involved belongs to subgroup 1 of group A rotaviruses.