Journal Article

Defactinib inhibits PYK2 phosphorylation of IRF5 and reduces intestinal inflammation

Bonham, Sarah, Ryzhakov, Grigory, Jostins-Dean, Luke, Almuttaqi, Hannah, Berthold, Dorothée L., Fischer, Roman, Corbin, Alastair L., Ai, Zhichao, Travis, Simon P. L., Udalova, Irina A., Kessler, Benedikt M., Pearson, Claire, Khoyratty, Tariq, Eames, Hayley L., Zec, Kristina, Bullers, Samuel

2021

Overview

Interferon regulating factor 5 (IRF5) is a multifunctional regulator of immune responses, and has a key pathogenic function in gut inflammation, but how IRF5 is modulated is still unclear. Having performed a kinase inhibitor library screening in macrophages, here we identify protein-tyrosine kinase 2-beta (PTK2B/PYK2) as a putative IRF5 kinase. PYK2-deficient macrophages display impaired endogenous IRF5 activation, leading to reduction of inflammatory gene expression. Meanwhile, a PYK2 inhibitor, defactinib, has a similar effect on IRF5 activation in vitro, and induces a transcriptomic signature in macrophages similar to that caused by IRF5 deficiency. Finally, defactinib reduces pro-inflammatory cytokines in human colon biopsies from patients with ulcerative colitis, as well as in a mouse colitis model. Our results thus implicate a function of PYK2 in regulating the inflammatory response in the gut via the IRF5 innate sensing pathway, thereby opening opportunities for related therapeutic interventions for inflammatory bowel diseases and other inflammatory conditions. The transcription factor, IRF5, has been implicated in the regulation of inflammation, but how IRF5 protein is activated is still unclear. Here the authors use inhibitor library screening, biochemical analyses and in vivo/ex vivo data to show that a protein tyrosine kinase, Pyk2, may be key for the activation of IRF5 in macrophages and inflammatory responses in the gut.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 101/58 / 13/109 / 13/21 / 13/95 / 38/90 / 38/91 / 45/15 / 631/250/2504/342 / 631/250/256 / 631/250/262 / 631/250/516 / 64/60 / Animals / Benzamides - pharmacology / Biopsy / Cell activation / Cells, Cultured / Colitis - genetics / Colitis - metabolism / Colitis - prevention & control / Colon / Cytokines / Cytokines - genetics / Cytokines - metabolism / Digestive system / Enzyme inhibitors / Focal Adhesion Kinase 2 - genetics / Focal Adhesion Kinase 2 - metabolism / Gastrointestinal tract / Gene expression / Gene Expression Profiling - methods / HEK293 Cells / Humanities and Social Sciences / Humans / Immune response / Inflammation / Inflammation - genetics / Inflammation - metabolism / Inflammation - prevention & control / Inflammatory bowel disease / Inflammatory bowel diseases / Inflammatory response / Interferon / Interferon Regulatory Factors - genetics / Interferon Regulatory Factors - metabolism / Intestines - pathology / Kinases / Libraries / Macrophages / Macrophages - drug effects / Macrophages - metabolism / Male / Mice / Mice, Inbred C57BL / multidisciplinary / Mutation / Phosphorylation / Phosphorylation - drug effects / Protein-tyrosine kinase / Protein-tyrosine kinase 2 / Proteins / Pyrazines - pharmacology / RAW 264.7 Cells / Science / Science (multidisciplinary) / Sulfonamides - pharmacology / Therapeutic applications / Transcriptomics / Tyrosine / Ulcerative colitis