FIG 1 .

Infection of monocytes with Titan-ΔUS28 results in lytic infection. CD14⁺ peripheral blood monocytes were isolated and experimentally infected at an MOI of 5 with HCMV Titan-WT or Titan-ΔUS28. (A) Seven days postinfection, RNA from these cultures was harvested and analyzed for expression of the latency-associated UL138 gene, the major immediate early lytic IE1 gene, and the major late UL99 gene. Data were normalized to GAPDH RNA. (B) Seven days postinfection, monocytes were also fixed and stained for IE protein and UL32-GFP (using an antibody against the GFP tag). (C) These monocyte cultures were then cocultured with HFFs, and the number of infected HFFs was measured by staining for cells expressing HCMV IE protein at 72 h postcoculture. All data points show means of results from at least four independent experiments; error bars show standard deviations. *, P = 0.05 (statistically significant result; calculated using Student’s t test).