A chromatin-regulated biphasic circuit coordinates IL-1β-mediated inflammation.
Ezio T FokSimone J C F M MoorlagYutaka NegishiLaszlo A GrohJéssica Cristina Dos SantosCathrin GräweValerie Villacorta MongeDaphne D D CraenmehrMellanie van RoosmalenDavid Pablo da Cunha JolvinoLetícia Busato MiglioriniAry Serpa NetoPatricia SeverinoMichiel VermeulenLeo A B JoostenMihai M NeteaStephanie FanucchiMusa M MhlangaPublished in: Nature genetics (2023)
Inflammation is characterized by a biphasic cycle consisting initially of a proinflammatory phase that is subsequently resolved by anti-inflammatory processes. Interleukin-1β (IL-1β) is a master regulator of proinflammation and is encoded within the same topologically associating domain (TAD) as IL-37, which is an anti-inflammatory cytokine that opposes the function of IL-1β. Within this TAD, we identified a long noncoding RNA called AMANZI, which negatively regulates IL-1β expression and trained immunity through the induction of IL37 transcription. We found that the activation of IL37 occurs through the formation of a dynamic long-range chromatin contact that leads to the temporal delay of anti-inflammatory responses. The common variant rs16944 present in AMANZI augments this regulatory circuit, predisposing individuals to enhanced proinflammation or immunosuppression. Our work illuminates a chromatin-mediated biphasic circuit coordinating expression of IL-1β and IL-37, thereby regulating two functionally opposed states of inflammation from within a single TAD.