TGFB1 and cytomegalovirus infection: HCMV infected HK-2 cells (HCMV TR+/raTGF-β1-) also produced similar amounts of active TGF-β1 compared to uninfected cells, indicating that HCMV infection alone did not induce de novo TGF-β1 production in these epithelial cells (Figure 3A).