CD4⁺ CD8αα⁺ double-positive intraepithelial T lymphocytes (DP T cells), a newly characterized subset of intraepithelial T cells, are reported to contribute to local immunosuppression. However, the presence of DP T cells in Helicobacter. pylori -induced gastritis and their relationship with disease prognosis has yet to be elucidated. In this study, a chronic gastritis model was established by infecting mice with Helicobacter felis. Gastric-infiltrating lymphocytes were isolated from these mice and analyzed by flow cytometry. The frequency of DP T cells in H. felis-induced gastritis mice was higher than that in uninfected mice. The gastric DP T cells were derived from lamina propria cells but were predominantly distributed in the gastric epithelial layer. These gastric DP T cells also exhibited anti-inflammatory functions, and they inhibited the maturation of dendritic cells and proliferation of CD4⁺ T lymphocytes in vitro. Elimination of DP T cells simultaneously resulted in severe gastritis and a reduction of H. felis load in vivo. Finally, vaccine mixed with different adjuvants was used to explore the relationship between vaccine efficacy and DP cells. Silk fibroin as the vaccine delivery system enhanced vaccine efficacy by reducing the number of DP T cells. This study demonstrated that DP T cells perform an immunosuppressive role in Helicobacter felis-induced gastritis, and consequently, DP T cells may affect disease prognosis and vaccine efficacy.

据报道，CD4 ⁺ CD8αα ⁺双阳性上皮内 T 淋巴细胞（DP T 细胞）是一种新表征的上皮内 T 细胞亚群，有助于局部免疫抑制。然而，在螺杆菌中存在DP T细胞。pylori诱发的胃炎及其与疾病预后的关系尚未阐明。本研究通过猫螺杆菌感染小鼠建立慢性胃炎模型。从这些小鼠中分离出胃浸润淋巴细胞并通过流式细胞术进行分析。H. felis中DP T细胞的频率诱导性胃炎小鼠高于未感染小鼠。胃 DP T 细胞来源于固有层细胞，但主要分布在胃上皮层。这些胃DP T细胞还表现出抗炎功能，它们在体外抑制树突细胞的成熟和CD4 ⁺ T淋巴细胞的增殖。DP T 细胞的消除同时导致严重的胃炎和体内河猫负荷的减少. 最后，通过混合不同佐剂的疫苗来探索疫苗效力与DP细胞之间的关系。丝素蛋白作为疫苗递送系统通过减少 DP T 细胞的数量来增强疫苗效力。该研究表明DP T细胞在猫螺杆菌诱导的胃炎中发挥免疫抑制作用，因此，DP T细胞可能影响疾病预后和疫苗效力。