Mucosal-associated invariant T (MAIT) cells rapidly produce proinflammatory cytokines in an innate-like manner and play an important role in controlling the host immune response. This study examined the function of MAIT cells in trauma patients. The expression of cytokines in peripheral blood MAIT cells was measured by flow cytometry. MAIT cells in trauma patients displayed impaired tumor necrosis factor (TNF)-α production, together with elevated CD69 expression. The expression of CD69 was negatively correlated with MAIT cell frequency. These patients had higher plasma levels of interleukin (IL)-12 and IL-18. In particular, CD69 expression of MAIT cells was increased by stimulation with IL-18 in synergy with other proinflammatory cytokines or plasma of trauma patients. The production of TNF-α by MAIT cells was characterized by an initial burst and rapid decline, in contrast to delayed and sustained production of interferon (IFN)-γ. Activated MAIT cells showed a functional defect in the production of TNF-α upon restimulation. This study demonstrates that circulating MAIT cells are activated and functionally impaired in TNF-α production in patients with trauma. The activation and dysfunction of MAIT cells was mediated by proinflammatory cytokines. These findings provide important information underlying the innate immune response of patients with trauma.

中文翻译：

---

创伤患者循环黏膜相关不变T细胞的活化和肿瘤坏死因子-α的产生

粘膜相关不变T（MAIT）细胞以先天性方式快速产生促炎细胞因子，并在控制宿主免疫反应中起重要作用。这项研究检查了创伤患者中MAIT细胞的功能。通过流式细胞术测量外周血MAIT细胞中细胞因子的表达。创伤患者中的MAIT细胞显示受损的肿瘤坏死因子（TNF）-α产生，以及CD69表达升高。CD69的表达与MAIT细胞频率呈负相关。这些患者血浆中白介素（IL）-12和IL-18的水平较高。特别是，通过与创伤患者的其他促炎细胞因子或血浆协同作用的IL-18刺激，MAIT细胞的CD69表达增加。与干扰素（IFN）-γ的延迟和持续产生相反，MAIT细胞产生TNF-α的特征在于初始爆发和快速下降。重新刺激后，活化的MAIT细胞在TNF-α的产生中显示出功能缺陷。这项研究表明，创伤患者的循环MAIT细胞在TNF-α产生中被激活并功能受损。MAIT细胞的激活和功能障碍是由促炎细胞因子介导的。这些发现为创伤患者的先天免疫反应提供了重要的信息。这项研究表明，创伤患者的循环MAIT细胞在TNF-α产生中被激活并功能受损。MAIT细胞的激活和功能障碍是由促炎细胞因子介导的。这些发现为创伤患者的先天免疫反应提供了重要的信息。这项研究表明，创伤患者的循环MAIT细胞在TNF-α产生中被激活并功能受损。MAIT细胞的激活和功能障碍是由促炎细胞因子介导的。这些发现为创伤患者的先天免疫反应提供了重要的信息。