Figure 1.

IAV replication in neutrophils was restricted by PAR₂ activation and IFNγ. (a) Replication of IAV in neutrophils was determined by detection of NS-1 mRNA levels at different time points after infection. At 4 hrs, a significant induction of NS-1 mRNA expression was revealed. In noninfected neutrophils NS-1 mRNA was not detectable. (b) IAV-infected neutrophils were treated with agonists as indicated for 20 hrs. Analysis of IAV titers showed a significant reduction in PAR₂ agonist and PAR₂ agonist/IFNγ treated neutrophils. (c) In cells that were primed with agonists for 2 hrs, infected with IAV for 30 min, and rechallenged with agonists for 20 hrs, both PAR₂ agonist and IFNγ decreased viral replication. Moreover, combining PAR₂ agonist and IFNγ further reduced IAV titers as compared to both agonists alone. For student's t-test: ^#,∗ P < 0.05; **P < 0.01; ***P < 0.005. The symbol ∗ marks the significance as compared to control and the symbol # as compared to IFNγ sample.