Effects of NMB and NMBRA treatment on the expression of cytokines in mice. Lung tissues from treated mice were sampled at 3 dpi. The expression patterns of IFN-α and IL-6 in lung tissues were assessed using RT-PCR and qRT-PCR. NMB treatment induced the upregulation of IFN-α (A, B) and downregulation of IL-6 (A, C); NMBRA treatment induced the downregulation of IFN-α (D, E) and upregulation of IL-6 (D, F). β-Actin was used as the reference housekeeping gene for internal standardization *P < 0.05; **P < 0.01.