Comparison of WNV_IS98 and WNV_KUN35911-induced apoptosis in hippocampus.

<p>Photomicrographs are representative of (A) CA3-hilus and (B) CA1 areas. Four micrometer coronal brain sections were stained for TUNEL (a-c, green), cleaved caspase 3 (d-f, red) and merged (g-i). (C) Neuronal loss in the CA1 pyramidal layer of WNV_KUN35911- but not WNV_IS98-infected mice. Brain sections were immuno-stained with anti-NeuN (a-c). (d) Total number of neurons per field in the CA1 area. Total number of (D) TUNEL-positive cells and (E) cleaved caspase 3-positive cells. (F) Percentage of cleaved caspase-3 positive cells among TUNEL-positive cells. Two sections were counted per mouse. Data represent the mean values +/- SD from 4 (WNV_KUN35911 – 10² PFU) to 5 (WNV_KUN35911 – 10³ PFU and WNV_IS98 – 10² PFU) mice. Statistical analyses were performed by employing the One-way ANOVA test. ns, not significant, **, P<0.01, ***, P<0.001.