Role of Peptidyl arginine deiminase 4-dependent macrophage extracellular traps formation on Type 1 Diabetes pathogenesis

Excessive macrophage extracellular traps (METs) formation has been implicated in several autoimmune disease pathogenesis; however, its impact on Type 1 Diabetes (T1D) and related mechanisms remains enigmatic. Here, we demonstrated the pivotal role of peptidyl arginine deiminase 4 (PAD4) in driving profuse METs formation and macrophage M1 polarization in intestinal inflammation of non-obese diabetic (NOD) mice. Genetic knockout of PAD4 or adoptive transfer of METs alters the proportion of pro-inflammatory T cells in the intestine, subsequently influencing their migration to the pancreas. Combining RNA sequencing and CUT&Tag analysis we found activated PAD4 transcriptionally regulated CXCL10 expression. This study comprehensively investigated how excessive PAD4-mediated METs formation in the colon increases the aggravation of intestinal inflammation and pro-inflammatory T cells migration, and finally involves T1D progression, suggesting that inhibition METs formation may be a potential therapeutic target for T1D.