Heterogeneous pathological outcomes after experimental pH1N1 influenza infection in ferrets correlate with viral replication and host immune responses in the lung

Vidaña, Beatriz; Martínez, Jorge; Martínez-Orellana, Pamela; García Migura, Lourdes; Montoya, María; Martorell, Jaime; Majó, Natàlia

Histopathological scores and positive cell quantification data were expressed as the means ± the standard errors of the mean (SEMs). The correlations between the IAV antigen quantifications and the histopathological scores of each animal were calculated by linear regression. Despite the small number of animals used in each infectious group, statistical analyses were performed. Comparisons of the immunophenotypes and the IAV antigen quantifications between the animals that were infected with the R11 and the R61 viruses and comparisons between animals with severe and mild lung lesions were performed using a non-parametric one-way analysis of variance (Kruskal-Wallis) followed when necessary by a Mann-Whitney U test. A robust analysis (one iteration) was used to obtain the means ± the SEMs for the RT-qPCR data. RT-qPCR comparisons between animals infected with the R11 and the R61 viruses and comparison between animals with severe and mild lung lesions were performed using Student's t-tests. In all cases, the results were considered statistically significant when the P value was < 0.05. All statistical analyses and data visualisation were performed with GraphPad Prism 6 (GraphPad Software, La Jolla, CA, USA).