Figure 5From: Neonatal influenza infection causes pathological changes in the mouse brainApoptotic cell death caused by neonatal influenza infection. (A) A representative image of a terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay in virus-infected brain shows many TUNEL-positive cells in the thalamus, which indicates cells degenerating by apoptosis. Double-immunofluorescence staining for TUNEL (Red, B-C) and the neuronal marker (NeuN, green, B) or astrocyte marker (GFAP, green, C) show either neurons or astrocytes undergoing apoptotic cell death (arrows in B, C). Scale bar for A = 100 μm; for B = 50 μm; for C = 25 μm. (D) Comparison of cell viability with pan-caspase inhibitor treatment in influenza-infected primary brain cell culture. Primary cultured neuronal cells (105 cells/well) were treated with a Z-VAD-FMK inhibitor (20 μM) after virus inoculation. Statistical analysis of the three groups shows a significant increase in cell viability with pan-caspase inhibitor treatment. The different numbers above the bars indicate significant statistical difference (Dunn’s multiple comparison test, mean ± SEM, p < 0.0001).Back to article page