Figure 6. Tmprss2 knock-out mice show reduced body weight loss and mortality after infection with low dose H3N2 influenza A virus infections.

Eight to eleven weeks old female mice were infected with 10¹ FFU mouse-adapted H3N2 influenza virus by intra-nasal application and bodyweight (A) and survival (B) was monitored until day 14 p.i. In addition to mice that were found dead, mice with a weight loss of more than 30% of the starting body weight were euthanized and recorded as dead. Homozygous Tmprss2 knock-out mice lost significantly less weight than wild type (e.g. p = 0,0006 at day 7, and p = 0,0006 at day 8, using MWU test) mice and showed reduced mortality compared to wild type mice, although this difference was not significant (using the log rank test).