Epigenetics compound library screening

The Epigenetics Compound Library with a unique collection of 181 epigenetics compounds (Cat L1900, Selleckchem, USA) was used as the inhibitor source. The library was purchased and obtained in January 2018 and the list of compounds in the library was shown in Supplementary Table ¹. For the screening assay, BG-trained or LPS-tolerant macrophages were pretreated with the inhibitors at two concentrations of inhibitory concentration 50 (IC50) from the manufacturer’s data for 1 h and during the priming or stimulation phase. Control cells received vehicle control DMSO and were subjected to the same priming. Cells were cultured in the presence of inhibitors during priming or stimulation for 24 h. The culture supernatant was subjected to ELISA to measure TNFα. The relative amount of TNFα was calculated as the fold change of the inhibitor-treated cells compared with the vehicle control-treated cells. The inhibitors that showed enhancing or suppressing effects with fold changes of 1.5-fold or higher and 0.75-fold or lower, respectively, were chosen for further confirmation. Interaction of the potential targets identified in this study was performed with STRING version 11.0 (https://string-db.org/)²¹.