Transcriptional effects of siRNA-mediated MAFB knockdown on SARS-CoV-2-infected human M-CSF and GM-derived macrophages.

To investigate the MAFB-dependent genes in the SARS-COV-2 infection on human macrophages, we generated M-CSF and GM-CSF-dependent monocyte-derived macrophages in which MAFB has been knocked down by siRNA and then infected with SARS-CoV-2. Monocytes from three independent donors (0.5 x 106 cells/ml, >95% CD14+ cells) were cultured in RPMI 1640 supplemented with 10% fetal bovine serum (FBS) at 37°C in a humidified atmosphere with 5% CO2 for 6 days in the presence of GM-CSF or M-CSF, with cytokine addition every two days. Then, monocyte-derived macrophages were transfected with MAFB-specific siRNA or control siRNA, kept in culture for 6 hours, and then were exposed to SARS-CoV-2 (SARS-CoV-2 clinical isolate Gisaid EPI_ISL_1120962, corresponding to ancestral S D614G, at an MOI=1) or uninfected. After 36 hours, cells were lysed and RNA isolated for transcriptional analysis. We performed gene expression profiling analysis using data obtained from RNA-seq of 3 different donors. Overall design: Comparative gene expression profiling analysis of RNA-seq data for cells transfected with siMAFB (siMAFB_GM/siMAFB_M) or siControl (siCNT_GM/siCNT_M) exposed or not to SARS-COV-2 (MOI).