FIG. 4.

Representative CAT assay demonstrating clarithromycin-induced inhibition of NF-κB-mediated transcription by TNF-α in U-937 cells transfected with the HIV-1 LTR CAT gene. The clarithromycin-pretreated cells treated with TNF-α for 2 h expressed less activity than the non-clarithromycin-pretreated cells. The results are expressed as fold increases in activity over that in the cells treated with the medium alone (control). ∗, P < 0.05; ∗∗, P < 0.01.