Figure 1.

Safety of ZIKV^BR Intrathecal Injection in Dogs

(A) Viral RNA copies of peripheral blood serum at 3, 6, and 9 days after ZIKV^BR intrathecal injection in Pitbull immunosuppressed dog. (B) Viral titer in testicle, kidney, prostate bladder, and CSF samples at euthanasia in Pitbull dog, 18 days after ZIKV^BR injection (∗∗∗∗p < 0.0001). (C and D) Representative images of frontal lobe (C) and medulla (D) CNS tissues IF immunolabeling for ZIKV^BR (red), and nuclei DAPI (blue). Scale bar, 20 μm. (E) Representative images of neurons from CNS tissues IF immunolabeling for ZIKV^BR (red), β3-tubulin cytoplasmatic (green) protein, and nuclei DAPI (blue). Yellow staining in neuron image (E) shows unspecific staining for lipofuscin accumulation. Scale bar, 20 μm. (F) H&E representative images of urologic tissues: prostate (Fʹ) and testicle (Fʹʹ). Scale bar, 100 μm. (G) Representative spleen tissue of H&E (Gʹ) and IHC immunolabeling for ZIKV^BR (brown) and hematoxylin (blue) (Gʹʹ). Scale bar, 100 μm. (H) Representative lymph node tissue of H&E (Hʹ) and IHC immunolabeling for ZIKV^BR (brown) and hematoxylin (blue) (Hʹʹ). Scale bar, 500 μm. The brown areas in H&E preparation of spleen (Gʹ) and lymph node tissue (Hʹ) suggests a hemosiderin accumulation. Canine ZIKV-IgG and ZIKV-IgM quantification by ELISA in peripheral blood serum (I) and CSF (J) dog samples. (∗p < 0.05; ∗∗p < 0.01; ∗∗∗p < 0.001; ∗∗∗∗p < 0.0001, two-way ANOVA with Bonferroni multiple comparison test. Three technical replicas for each sample).