Jadie Y. Moon, Sonya Wolf, Amrita Joshi, He Zhang, James Shadiow, Tyler M. Bauer, Kevin Mangum, Lindsey D. Hughes, Christopher O. Audu, William J. Melvin, Emily Barrett, Sabrina Rocco, Gabriela Saldana de Jimenez, A.L. Estor, Moses Nelapudi, Qinmengge Li, Rachael Bogle, Benjamin Lévi, Frank M. Davis, Andrea T. Obi, Bethany B. Moore, Lam C. Tsoi, Jóhann E. Guðjónsson, Katherine Gallagher
IL-17A is a cytokine critical for tissue repair, but in excess, it prolongs inflammation and impairs healing. In type 2 diabetic (T2D) wounds, keratinocyte functions, including migration and inflammation, are disrupted, though mechanisms remain unclear. Here, we demonstrate that IL-17A regulates keratinocyte dysfunction via induction of the histone demethylase Jumonji domain-containing protein 3 (JMJD3) through a TRAF6/NFκB pathway. JMJD3 removes repressive histone 3 lysine 27 (H3K27me3) marks at anti-migratory (Itga3, Timp1) and inflammatory (Ccl20, Cxcl1, Cxcl3, Cxcl5) gene promoters, increasing transcription. Human and murine diabetic wounds exhibit elevated IL-17A signaling, JMJD3, and expression of associated anti-migratory and inflammatory genes compared to controls. Importantly, keratinocyte-specific deletion of IL-17A signaling or JMJD3 in diabetic mice improves wound healing and decreases expression of JMJD3 target genes. These findings reveal an IL-17A/JMJD3-mediated mechanism driving keratinocyte dysfunction in T2D wounds and highlight the therapeutic potential of targeting this axis to enhance wound repair. IL-17A, a cytokine important for tissue repair, can impair healing when increased, contributing to keratinocyte dysfunction in type 2 diabetic wounds. Here, the authors show that IL-17A drives this dysfunction via JMJD3-mediated epigenetic changes, and that blocking this pathway improves wound healing.