GFI1B and cytomegalovirus infection: To determine whether HCMV infection depends on the down-regulation of GFI1, human foreskin fibroblasts were transduced with pBabe-puro-based retroviral constructs of GFI1 or GFI1B, a GFI1-related gene, also encoding a SNAG domain-containing transcriptional repressor, or with the empty vector.