CRISPR Screens Map Interferon Regulation in Monocytes

The Danish researchers used a CRISPR-­ Cas9 lentiviral library to screen THP-1 cells carrying a fluorescent IFNB1 reporter, comparing cells stimulated with cGAMP alone with cells first primed with IFN-α to model an ongoing inflammatory response. They identified 356 supporting and 217 restricting genes without priming, and 311 supporting and 177 restricting genes after priming. Only 13-14% had previously been linked to interferon or STING regulation.

Individual knockouts validated seven of nine supporting genes and eight of nine restricting genes. Several restricting genes belonged to autophagy pathways that terminate STING signalling, whereas RNA-processing and chromatin-associated genes influenced the magnitude and context of the response.

Loss of TBL1XR1 reduced IFNB1 expression after activation of cGAS-STING, RIG-I-like receptors and Toll-like receptors, as well as during herpes simplex virus 1 infection. Experiments suggested that TBL1XR1 cooperates with the deacetylase HDAC3 to support TBK1 activation and interferon-dependent transcription through the NCoR/SMRT complex.

The CRISPR-Cas9 screens were performed in a transformed cell line, and some regulatory relationships may not extend to primary monocytes or other cell types.

The study was led by Emil Aagaard Thomsen and Jacob Giehm Mikkelsen at Aarhus University, Denmark. It was published in Science Signaling on 18 August 2026.