Duration and strain-specificity of immunity to enterotropic mouse hepatitis virus.
We examined the duration and strain-specificity of immunity to enterotropic mouse hepatitis virus (MHV). Two strains of enterotropic MHV (MHV-Y and MHV-RI) were determined to be distinct virus strains by serum neutralization and by enzyme immunoassay. BALB/cByJ mice immunized by oral infection with either MHV-Y or MHV-RI developed serum MHV IgG titers that remained stable for more than 6 months. The animals were protected from reinfection with the homologous virus strain at 1 and 6 months after an initial immunizing infection, based on intestinal histology and polymerase chain reaction for a 375-base-pair segment of the membrane glycoprotein gene. Immunity was also fully protective against challenge with the heterologous strain 1 month after initial immunization and partly protective after 6 months. Maternally-derived passive immunity prevented MHV infection in 1-week-old pups challenged with the homologous strain of MHV, and pups challenged with the heterologous virus strain were partially protected.
Homberger
F R
FR
Section of Comparative Medicine, Yale University School of Medicine, New Haven, CT 06510.
Barthold
S W
SW
Smith
A L
AL
D000818:Animals; D001483:Base Sequence; D005260:Female; D006524:Hepatitis, Viral, Animal / Q000276:immunology*; D007110:Immunity, Active / Q000276:immunology*; D007114:Immunization / Q000662:veterinary; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D006517:Murine hepatitis virus / Q000276:immunology*; D013045:Species Specificity