Recombinant Strain A/HK/Otar/6:2/2010 (H3N8) for Development of a Live Intranasal Equine Influenza Vaccine

摘要

Recombinant cold-adapted strain A/HK/Otar/6:2/2010 (H3N8) constructed by the method of classic genetic reassortment, inherited the hemagglutinin and neuraminidase genes from the epizootic A/equine/Otar/764/2007 (H3N8) virus and genes of nonglycosylated proteins from attenuation donor A/Hong Kong/1/68/162/35 (H3N2). The resulted virus was of cold-adapted (efficient growth at 25 degrees C) and temperature-sensitive (restricted replication at 39 degrees C) phenotype. Like the parental virus of subtype H3N2, the resulted reassortant was attenuated, with limited replication in lungs of mice (1.75 IgEID(50)/mL) versus replication in turbinate (2.5 IgEID(50)/mL). Intranasal immunization of mice with A/HK/Otar/6:2/2010 (H3N8) reassortant did not induce animal weight reduction in contrast to epizootic A/equine/Otar/764/2007 (H3N8) virus