Fig 12. Amantadine improves growth of avian M segment-encoding virus in A549 cells.

PR8-based NL09 M or avian M-encoding viruses were inoculated at an MOI of 5 PFU/cell onto A549 cells. At 1hpi, cells were treated with 200μM amantadine, and incubated at 37°C for 24 h in the continuous presence of amantadine. Virus released into supernatant was collected at the indicated time points, and virus growth was measured by plaque titration. The pH1N1 M segment conferred more rapid kinetics and higher peak titers of growth than the avian-origin M segment, however amantadine had no impact on the growth of the pH1N1 M encoding virus. In contrast, growth of the avian M-encoding virus was improved in the presence of drug (P = 0.0007). Single-cycle growth was assessed in four independent experiments, with three technical sample replicates per experiment. Graphs show the means with SD for the four experiments. Statistical significance was determined using repeated measures, two-way, multiple comparisons ANOVA on log-transformed values, with Sidak’s correction applied.