Immunofluorescent detection of polyclonal antibody against orf virus demonstrates viral infection of MDA-MB-468 xenograft tumor tissue harvested one week after intratumoral CF189 injection. (A) Control tumor, 10X, (B) Tumor from 105 PFU treatment group, 10X, (C) Tumor from 105 PFU treatment group, 60X. (ORF: red; DAPI counterstain: blue).