Invasion of H9N2 virus triggers the loss of functional Paneth cells. A–C RT-qPCR analysis of the expression of marker genes in Paneth cells [Lyz1 (A), defcr1 (B), and defa6 (C)] at 1, 12 and 48 h. The results are representative of data from duplicate three independent experiments. Each data bar shown represents mean values ± SE of triplicate assays. *P < 0.05; **P < 0.01. Bars: 30 μm.