Figure 1. IAV coinfection impairs control of Mtb.

(A) Timeline of experimental setup. (B and C) C57BL/6 mice were infected via aerosol with a low dose of Mtb H37Rv and 12 days later coinfected i.n. with 1 × 10⁴ PFU IAV (A/HH/05/09 H1N1). At indicated time points, bacterial burden in lung (B) and spleen (C) were determined (n = 6 [day 1, day 12 Mtb], n = 7–9 per group, data pooled from 2 independent experiments). (D and E) C57BL/6 mice received high-dose Mtb H37Rv aerosol infection and were coinfected i.n. with 1 × 10⁴ PFU IAV (A/HH/05/09 H1N1) 12 days later. (D) At indicated time points, pulmonary bacterial burden (n = 3; day 1, day 12 Mtb; n = 4–5 per group, data from 1 experiment) was determined. (E) Mice were monitored for survival (n = 8–9 per group, data from 1 experiment) until day 250 after Mtb infection. (B–D) Each data point represents 1 mouse. *P ≤ 0.05; **P ≤ 0.01, ***P ≤ 0.001 determined by (B and C) unpaired t test and (E) log-rank (Mantel-Cox) test.