GPR55 and periodontitis: LPIs are bioactive lipids known to activate downstream signalling pathways via receptors such as GPR55, regulating inflammation, cell proliferation, and migration.1 Given that periodontitis is characterised by chronic inflammation and tissue destruction, elevated genetically predicted 1-palmitoyl-GPI (16:0) may increase susceptibility by enhancing pro-inflammatory responses or promoting pathological cellular activities.