Aerosol vaccination with a sendai virus temperature-sensitive mutant (HVJ-pB) derived from persistently infected cells.

Experimental infections of mice with a Sendai virus temperature-sensitive (ts) mutant (HVJ-pB) were studied. Infection with the ts mutant induced the priming effect of interferon production and both humoral and cellular immune responses, although the ts mutant virus neither multiplied satisfactorily in the respiratory tracts of mice nor caused appreciable histopathologic lesions. Inoculation with the ts mutant protected mice from subsequent challenge with a parental wild-type virus. The efficacy of this protection began as little as 1 day after vaccination and continued for at least 12 weeks. It is suggested that serum antibodies were efficacious in the nasal turbinates, while specific immune spleen cells act more protectively in the lungs.