5．免疫応答/修飾—近年の研究から解明されてきたこと

Immune response and modification

熱傷は，激しい全身性炎症を引き起こし複雑な臨床経過を示す。これは損傷組織から放出される内因性分子（DAMPs）による自然免疫と獲得免疫の活性化による免疫反応であることが明らかとなってきた。近年，熱傷/外傷による組織損傷から放出されるDAMPsが数多く同定されるとともに，それを認識する自然免疫受容体も明らかとなり，組織損傷後の無菌性炎症の免疫学的理解が進んできた。熱傷後は免疫系が炎症と抗炎症のバランスをとりつつ恒常性を取り戻して治癒に向かうが，皮膚バリアが破綻する熱傷では感染症の合併も避けられない。免疫の安定化が得られず，長期にわたり免疫と異化の異常が持続するpersistent-inflammation immunosuppression and catabolism syndrome（PIICS）が近年問題視されている。

Burn injury causes severe systemic inflammation with a complex clinical course. It has become clear that this is an immune reaction caused by the activation of innate and acquired immunity by endogenous molecules：damage-associated molecular patterns （DAMPs）that are released from injured tissue. In recent years, many DAMPs released from injured tissue in burns/trauma have been identified, and innate immune receptors that recognize DAMPs have also been identified, leading to an improved immunological understanding of sterile inflammation after tissue damage. After a burn injury, the immune system balances inflammation and anti-inflammation and restores homeostasis for healing. However, in burn wounds where the skin barrier fails, complications of infection are inevitable. Persistent-Inflammation Immunosuppression and Catabolism Syndrome （PIICS）, in which long-term abnormalities of immunity and catabolism persist without stabilization of immunity, has recently been recognized.