To provide a therapeutic method and therapeutic composition for activating and amplifying an existing endogenous mechanism directed to suppressing a chronic inflammatory response.SOLUTION: According to the present invention, there is provided a nanoparticle comprising an antigen-MHC complex. Here, the complex comprises a MHC protein complexed with an antigen derived from a microorganism of the gastrointestinal tract or a GI-related antigen. The nanoparticle has a diameter selected from the group of diameters of approximately 1 nm to approximately 100 nm, approximately 5 nm to approximately 50 nm, or approximately 5 nm to approximately 15 nm. According to the present invention, there is also provided a therapeutic method using the nanoparticles.SELECTED DRAWING: None【課題】慢性的な炎症反応を抑制することに指向された既存の内因性メカニズムを活性化しかつ増幅する治療方法ならびに治療用組成物の提供。【解決手段】、抗原-MHC複合体を含むナノ粒子であって、該複合体が、胃腸管の微生物に由来する抗原と複合体化されたかまたはGI関連抗原である抗原と複合体化されたMHCタンパク質を含む、約1nm～約100nm、約5nm～約50nm、または約5nm～約15nmの直径の群より選択される直径を有するナノ粒子、および当該ナノ粒子を用いた治療方法。【選択図】なし
