Innate lymphoid cells (ILCs) are guardians of mucosal immunity, yet the transcriptional networks that support their function remain poorly understood. We used inducible combinatorial deletion of key transcription factors (TFs) required for ILC development (RORγt, RORα and T-bet) to determine their necessity in maintaining ILC3 identity and function. Both RORγt and RORα were required to preserve optimum effector functions; however, RORα was sufficient to support robust interleukin-22 production among the lymphoid tissue inducer (LTi)-like ILC3 subset, but not natural cytotoxicity receptor (NCR)⁺ ILC3s. Lymphoid tissue inducer-like ILC3s persisted with only selective loss of phenotype and effector functions even after the loss of both TFs. In contrast, continued RORγt expression was essential to restrain transcriptional networks associated with type 1 immunity within NCR⁺ ILC3s, which coexpress T-bet. Full differentiation to an ILC1-like population required the additional loss of RORα. Together, these data demonstrate how TF networks integrate within mature ILCs after development to sustain effector functions, imprint phenotype and restrict alternative differentiation programs.

先天淋巴细胞（ILC）是粘膜免疫的守护者，但支持其功能的转录网络仍然知之甚少。我们使用 ILC 发育所需的关键转录因子 (TF)（RORγt、RORα 和 T-bet）的诱导组合删除来确定它们在维持 ILC3 身份和功能方面的必要性。 RORγt 和 RORα 都需要保持最佳效应器功能；然而，RORα 足以支持淋巴组织诱导物 (LTi) 样 ILC3 亚群中强劲的白细胞介素 22 产生，但不能支持天然细胞毒性受体 (NCR) ⁺ ILC3。即使在两个 TF 均丢失后，类淋巴组织诱导物 ILC3 仍然存在，仅选择性丧失表型和效应功能。相比之下，持续的 RORγt 表达对于抑制 NCR ⁺ ILC3 内与 1 型免疫相关的转录网络至关重要，NCR + ILC3 共表达 T-bet。完全分化为 ILC1 样群体需要额外损失 RORα。这些数据共同证明了 TF 网络在发育后如何整合到成熟的 ILC 中，以维持效应器功能、印记表型并限制替代分化程序。