Much remains unknown about the roles of CD4⁺ T helper cells in shaping localized memory B cell and CD8⁺ T cell immunity in the mucosal tissues. Here, we report that lung T helper cells provide local assistance for the optimal development of tissue-resident memory B and CD8⁺ T cells after the resolution of primary influenza virus infection. We have identified a population of T cells in the lung that exhibit characteristics of both follicular T helper and T_RM cells, and we have termed these cells as resident helper T (T_RH) cells. Optimal T_RH cell formation was dependent on transcription factors involved in T follicular helper and resident memory T cell development including BCL6 and Bhlhe40. We show that T_RH cells deliver local help to CD8⁺ T cells through IL-21–dependent mechanisms. Our data have uncovered the presence of a tissue-resident helper T cell population in the lung that plays a critical role in promoting the development of protective B cell and CD8⁺ T cell responses.

关于 CD4 ⁺ T 辅助细胞在塑造黏膜组织中的局部记忆 B 细胞和 CD8 ^{+ T 细胞免疫方面的作用仍然未知。}在这里，我们报告肺 T 辅助细胞在原发性流感病毒感染消退后为组织驻留记忆 B 和 CD8 ^{+ T 细胞的最佳发育提供局部帮助。}我们已经确定了肺中的 T 细胞群，它们表现出滤泡 T 辅助细胞和 T _RM细胞的特征，我们将这些细胞称为常驻辅助 T (T _RH ) 细胞。最佳_TRH细胞形成依赖于参与 T 滤泡辅助细胞和常驻记忆 T 细胞发育的转录因子，包括 BCL6 和 Bhlhe40。我们表明，T _RH细胞通过 IL-21 依赖性机制向 CD8 ⁺ T细胞提供局部帮助。我们的数据揭示了肺中组织驻留的辅助 T 细胞群的存在，它在促进保护性 B 细胞和 CD8 ⁺ T 细胞反应的发展中起着关键作用。