Pooled CRISPR screens in human macrophages

To identify the possible genes influencing macrophage pro-inflammatory activation, we designed CRISPR screens using a human metabolic sgRNA library containing metabolism-related transcription factors, small molecule transporters, and metabolic enzymes in a Cas9-expressing lentiviral vector. THP-1 cells or iPSCs were transduced with a viral library for 24 h. After puromycin selection for seven days, the transduced cells were differentiated into macrophages, then stimulated by LPS plus IFN-γ for 24 h. The stimulated cells were harvested and stained with anti-human CD80-FITC for 15 min at room temperature. The CD80-high and CD80-low cells were separated by flow cytometry sorting.