Non-Mouse-Adapted H1N1pdm09 Virus as a Model for Influenza Research
The number of lung-adapted influenza viruses is limited. Most of them are not antigenically related to current circulating viruses. Viruses similar
to recent strains are required for screening modern antiviral compounds and studying new vaccine candidates against novel influenza viruses.
The process by which an influenza virus adapts to a new host is rather difficult. The aim of this study was to select a non-adapted current virus
whose major biological properties correspond to those of classical lab-adapted viruses. Mice were inoculated intranasally with non-lung-adapted
influenza viruses of subtype H1N1pdm09. They were monitored closely for body weight loss, mortality outcomes and gross pathology for 14
days following inoculation, as well as viral replication in lung tissue. Lung-adapted PR8 virus was used as a control. The tested viruses multiplied
equally well in the lower respiratory tract of mice without prior adaptation but dramatically differed in lethality; the differences in their toxicity
and pathogenicity in mice were established. A/South Africa/3626/2013 (H1N1)pdm09 virus was found to be an appropriate candidate to replace
PR8 as a model virus for influenza research. No prior adaptation to the animal model is needed to reach the pathogenicity level of the classical
mouse-adapted PR8 virus.
Mohammad Al Farroukh