Unified phase separation drives DNA-induced inflammasome activation of the AIM2-like receptors

AIM2-like receptors (ALRs) are critical for host defense by sensing intracellular foreign DNA and aberrant self-DNA to activate inflammasomes. Here, we demonstrate that both human and mouse AIM2 undergo liquid-liquid phase separation (LLPS) upon binding dsDNA. Multivalent interactions within the OB1 and OB2 subdomains of the AIM2 HIN domain are essential for LLPS and subsequent inflammasome activation. In AIM2 knockout THP-1 cells, LLPS-deficient AIM2 mutants exhibit markedly impaired inflammasome activation and antiviral responses. ASC recruitment promotes the solidification of AIM2-dsDNA condensates. Notably, HIN domains from multiple ALRs, including human AIM2, human IFI16, mouse AIM2, and porcine MNDAL, form dsDNA-induced condensates, suggesting that HIN-domain-mediated LLPS is a conserved mechanism across the HIN-200 family. Finally, we identify the α-herpesvirus tegument protein VP22 as a viral antagonist that disrupts AIM2-dsDNA LLPS to evade AIM2 inflammasome activation. Collectively, these findings elucidate a unified LLPS-dependent mechanism for ALR-mediated DNA sensing and inflammasome activation and uncover a viral immune evasion strategy targeting biomolecular condensates.