SILAC-based chemoproteomics reveals a neoligan analogue as an anti-inflammatory agent targeting IRGM to ameliorate cytokine storm.
Zhang J, Li Y, Meng G, Lu K, Yan J, Wu J, Li P, Luo L, Chen X, Zhao X, Qiu F.
Cytokine storm is a key feature of sepsis and severe stage of COVID-19, and the immunosuppression after excessive immune activation is a substantial hazard to human life. Both pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) are recognized by various pattern recognition receptors (PRRs), which lead to the immune response. A number of neolignan analogues were synthesized in this work and showed powerful anti-inflammation properties linked to the response to innate and adaptive immunity, as well as NP-7 showed considerable anti-inflammatory activity at 100 nM. On the sepsis model caused by cecum ligation and puncture (CLP) in C57BL/6J mice, NP-7 displayed a strong regulatory influence on cytokine release. Then a photo-affinity probe of NP-7 was synthesized and chemoproteomics based on stable isotope labeling with amino acids in cell cultures (SILAC) identified Immunity-related GTPase M (IRGM) as a target suppressing cytokine storm, which was verified by competitive pull-down, cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS) and molecular dynamics simulations.