Detection of HCMV DNA and IE transcripts in HCMV-infected CD34⁺ progenitor cells 3 and 7 days postinfection. (A) Ethidium bromide-stained 1% agarose gel of PCR products for HCMV DNA (lanes 1 through 3) and of RT-PCR for IE transcripts (lanes 4 through 6; 3 days postinfection). The arrow indicates the IE PCR and RT-PCR products of 332 bp. Lane 1, DNA from CD34⁺ cells infected with HCMV strain 95(2); lane 2, DNA from CD34⁺ cells infected with Towne/lox2; lane 3, DNA from mock-infected CD34⁺ cells; lane 4, RNA from CD34⁺ cells infected with 95(2); lane 5, RNA frm CD34⁺ cells infected with Towne/lox²; lane 6, RNA from mock-infected CD34⁺ cells. (B) Ethidium bromide-stained 1% agarose gel of RT-PCR products of an IE transcripts (7 days postinfection) using primers spanning exons 1 and 2. The arrows indicate the RT-PCR products of spliced IE transcripts of 218 bp and unspliced IE transcripts of 332 bp. Lane 1, RNA from CD34⁺ cells infected with 95(2); lane 2, RNA from CD34⁺ cells infected with Towne/lox²; lane 3, RNA from mock-infected CD34⁺ cells; lane 4, positive control of HCMV-infected fibroblasts amplified from DNA displaying genomic size (332 bp) banding pattern; lane 5, RT-PCR H₂O control. All RNA samples were treated with Rnase-free Dnase. Lane m, 100-bp ladder (GIBCO/BRL). Primers and predicted PCR products are listed in Table 1.