Expression of US3 protein in recombinant virus-infected cells. HEp-2 cells (A) or Vero cells (B) were infected at an MOI of 5 for 12 h with HSV-1(F) (lane 1), vRR1202 (lane 2), vRR1202rep (lane 3), vRR1204 #1 (lane 4), vRR1204 #2 (lane5), vRR1205 #1 (lane 6), or vRR1205 #2 (lane 7). Equal amounts of total infected cell proteins were separated by SDS-PAGE (8%), transferred to a nitrocellulose membrane, and probed with an anti-US3 antibody (conjugated with alkaline phosphatase).