Figure 7. Integrin αvβ5 Mediates In Vivo ZIKV Targeting of GSCs in Mouse Models and in Human GBM.
(A) Immunostaining of the subventricular zone (SVZ) of mice 72 h following ZIKV infection ZIKV-E (green), SOX2 (red, top panels), and integrin αvβ5 (red, bottom panels). Scale bars, 50 μm.
(B) Higher magnification of images from (A), demonstrating ZIKV infection of SOX2+ (top panels) and integrin αvβ5+ cells. Scale bars, 10 μm.
(C) Survival of ZIKV-infected NSG mice from (A) was plotted by the Kaplan-Meier method.
(D) ZIKV-infected brains from the mice in (A) were collected upon death, and histology was assessed by H&E staining. Scale bars, 20 μm.
(E) Survival of NSG mice following implantation of GSCs treated with isotype control, P1F6 antibody, ZIKV, combined P1F6 and ZIKV, combined CRISPR knockout (KO) of integrin β5 (sgRNA1 sgRNA2) with ZIKV inoculation, analyzed by log rank test; p < 0.01.
(F) H&E staining of tumor-bearing brains from (E). Scale bars, 50 μm.
(G) Intraoperative brain slices from GBM patients were pre-incubated with an IgG control antibody or an integrin-blocking antibody under mock conditions or upon ZIKV infection (10e3 FFU). Slices then underwent immunofluorescence staining for ZIKV-E (green), integrin αvβ5 (red), and DAPI (blue). Scale bars, 10 μm.
(H) Intraoperative brain slices from GBM patients were pre-incubated with an IgG control antibody or an integrin-blocking antibody under mock conditions or upon ZIKV infection. Slices then underwent a viral RNA copy assay by qRT-PCR. Experiments were performed in two biological replicates with three technical repeats. Values represent mean ± SEM. ****p < 0.0001 by one-way ANOVA.