a Young mice were administered a neutrophil depleting monoclonal antibody (i.p.) just prior to inoculation with influenza virus and following infection (as described in methods) and survival was monitored. Compared to isotype control treated, infected neutrophil depleted young mice exhibited a significant increase in mortality. * P < 0.05 (Log rank), n= 8–10 per group.
b Aged mice were treated per A and survival post infection was monitored. P value between neutrophil depleted and control group P = 0.23 (Log-Rank). n= 8–10 per group.
c Young mice were administered a neutrophil depleting antibody at day + 6 p.i. then intermittently to day +12 p.i. (as described in Methods) and compared to isotype control, treated young-infected mice. * P = 0.10 (Log-rank), n= 8–10 per group.
d Aged mice were treated according to c and survival was measured post infection. Aged neutrophil, depleted mice exhibited a significant increased survival as compared to control group. * P < 0.05 Log-rank, n= 8–10 per group.