Exactly how US28 modulates CTCF expression during latent infection of monocytes is not completely clear, though it appears to be post-transcriptional as latent infection of monocytes or overexpression of US28 in THP-1 cells has little effect on levels of CTCF RNA (Fig. 3f, g, respectively), and awaits further investigation. This evidence concerns the gene CTCF and disease arising from reactivation of latent virus.