Mactinin-induced production of cytokines from monocyts is blocked by Hsp90 inhibitors. Monocytes were incubated for 24 hrs with medium alone, mactinin alone or mactinin + one of 3 Hsp90 inhibitors (G: geldanamycin; A: 17-AAG; D: 17-DMAG). The concentrations of the indicated cytokines were determined in the supernatant. UD: undetectable at an assay sensitivity of 1.0 pg/ml. Data is shown as the mean +/- SEM. N = 3–4. Significance of differences between mactinin alone and the other conditions: *P < 0.01.