肠上皮细胞 (IEC) 损伤是乳糜泻 (CeD) 的一个标志；然而，其在麸质依赖性 T 细胞激活中的作用尚不清楚。我们研究了表达人 MHC II 类 (HLA-DQ2.5) 的类器官单层中的 IEC-麸质 -T 细胞相互作用，这有助于 CeD 中 CD4 T 细胞识别麸质抗原。在活性和治疗中测定了上皮 MHC II 类 (MHCII) CeD，以及未免疫和麸质免疫的 DR3-DQ2.5 转基因小鼠，缺乏小鼠 MHCII 分子。使用或不使用 IFN-γ 处理 DR3-DQ2.5 小鼠的类器官单层，并通过流式细胞术评估 MHCII 表达。将类器官单层和 CD4 T 细胞共培养物与谷蛋白一起孵育，预消化，或不通过产生弹性蛋白酶的铜绿假单胞菌或其 lasB 突变体进行孵育。根据共培养上清液中的增殖、激活标记物的表达和细胞因子释放来评估 T 细胞功能。活性 CeD 患者和麸质免疫的 DR3-DQ2.5 小鼠表现出上皮 MHCII 表达。来自麸质免疫的 DR3-DQ2.5 小鼠的类器官单层表达 MHCII，并被 IFN-γ 上调。在类器官单层 T 细胞共培养物中，麸质增加了共培养上清液中 CD4 T 细胞的增殖、T 细胞激活标记物的表达以及 IL-2、IFN-γ 和 IL-15 的释放。铜绿假单胞菌（而非 lasB 突变体）代谢的麸质增强了 CD4 T 细胞的增殖和活化。麸质抗原由表达 MHCII 的 IEC 有效呈递，导致麸质特异性 CD4 T 细胞的激活，而麸质预纯化可增强麸质特异性 CD4 T 细胞的激活。 -用微生物弹性蛋白酶消化。针对 IEC 的治疗可能为调节 CeD 患者的适应性和先天免疫提供一种新方法。版权所有 © 2024 AGA Institute。由爱思唯尔公司出版。保留所有权利。

Intestinal epithelial cell (IEC) damage is a hallmark of celiac disease (CeD); however, its role in gluten-dependent T-cell activation is unknown. We investigated IEC-gluten-T cell interactions in organoid monolayers expressing human MHC class II (HLA-DQ2.5), which facilitates gluten antigen recognition by CD4+ T cells in CeD.Epithelial MHC class II (MHCII) was determined in active and treated CeD, and in non-immunized and gluten-immunized DR3-DQ2.5 transgenic mice, lacking mouse MHCII molecules. Organoid monolayers from DR3-DQ2.5 mice were treated with or without IFN-γ, and MHCII expression was evaluated by flow cytometry. Organoid monolayers and CD4+ T cell co-cultures were incubated with gluten, pre-digested, or not by elastase-producing Pseudomonas aeruginosa or its lasB mutant. T cell function was assessed based on proliferation, expression of activation markers, and cytokine release in the co-culture supernatants.Active CeD patients and gluten-immunized DR3-DQ2.5 mice demonstrated epithelial MHCII expression. Organoid monolayers derived from gluten-immunized DR3-DQ2.5 mice expressed MHCII, which was upregulated by IFN-γ. In organoid monolayer-T cell co-cultures, gluten increased the proliferation of CD4+ T cells, expression of T cell activation markers, and the release of IL-2, IFN-γ, and IL-15 in co-culture supernatants. Gluten metabolized by P. aeruginosa, but not the lasB mutant, enhanced CD4+ T cell proliferation and activation.Gluten antigens are efficiently presented by MHCII-expressing IECs, resulting in the activation of gluten-specific CD4+ T cells, which is enhanced by gluten pre-digestion with microbial elastase. Therapeutics directed at IECs may offer a novel approach for modulating both adaptive and innate immunity in CeD patients.Copyright © 2024 AGA Institute. Published by Elsevier Inc. All rights reserved.