cHV68 WUMS (ATCC VR-1465) and all recombinant viruses were grown and titered as previously described [72] . DK3TET 2 cHV68 (cHV68-GFP) containing a GFP cassette under the control of an immediate early CMV promoter was generated and characterized by Dr. Phillip Stevenson [73] . cHV68 containing a stop codon within ORF 72 (v-cyclin.STOP. cHV68) was previously described [18] .