In-Situ Hybridization of Varicella-Zoster Virus

ISH was performed using the RNAScope 2.5 HD Assay and probes directed to SVV VLT (core VLT exons 1–3; cat# 549461), SVV ORF63 (cat# 438091), universally expressed positive control gene ubiquitin C (UBC) and negative control bacterial transcript DapB (all from Advanced Cell Diagnostics). Staining was visualized using FastRed as a substrate, nuclei were stained with hematoxylin and slides were mounted with Ecomount (Biocare Medical). ISH was performed on normal skin and varicella skin rash of n = 2 animals (AGM 269 and 279 in [23 (link)]), with n = 2 independent experiments and 3–4 skin biopsies per tissue section. Additionally, we performed ISH on 21 DRG from n = 2 animals (RM 2207 and RM 9021, [40 (link)]), encompassing 3 or 4 sacral ganglia and 7 lumbar ganglia per animal.