The ORF3 encodes a predicted 179 amino acid protein with a potential role in gene expression. Several studies showed ORF3 protein as dispensable for viral replication and establishment of latency. Thus, its exact function in the infected cells is not yet clarified. Our anti-VZV ORF3 antibody VZ 3.01 (described in J Virol. 2013 Jun;87(12):6943-54.) works in ELISA (on immunogen) and IF (on VZV infected cells) and each LOT is validated for Western blot (of VZV infected cell lysates) where it specifically recognizes a protein species of ~20 kDa in lysates obtained from VZV infected cells.