Chen Yao, Zhou Weitao, Li Leying, Chen Tong, Wu Qi, Li Qifan, Zhou Yufeng, Qian Liling
Department of Pulmonary Medicine, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China.
Department of Pulmonary Medicine, Shanghai Children's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
Transl Pediatr. 2025 Aug 31;14(8):1908-1920. doi: 10.21037/tp-2025-122. Epub 2025 Aug 27.
The non-canonical NF-κB2 pathway is crucial for immune regulation, and pathogenic mutations in NF-κB2 are linked to common variable immunodeficiency (CVID), recurrent infections, and autoimmune diseases. T follicular helper (Tfh) cells play a key role in B cell differentiation and antibody production, but the effects of NF-κB2 mutations on Tfh cell differentiation remain unclear. This study investigates the clinical and functional consequences of two NF-κB2 mutations: c.1714G>A (p.A572T) and c.2540dupT (p.R848Efs*38).
We analyzed clinical features, immunophenotypes, and endocrine profiles of three patients carrying NF-κB2 mutations. Transcriptome sequencing of peripheral blood mononuclear cells (PBMCs) from Patient 3 (P3) and five healthy donors was performed to examine gene expression changes. Flow cytometry quantified Tfh cell populations, and real-time quantitative polymerase chain reaction (RT-qPCR) validated the expression of genes involved in Tfh differentiation. The impact of NF-κB2 mutations on p100 processing and nuclear translocation was assessed via western blot and immunofluorescence in HEK293T cells.
Patient 1 (P1) exhibited mild clinical features, primarily asthma, while Patient 3 (P3) presented with severe immunodeficiency, recurrent pulmonary infections, and hormonal deficiencies. Transcriptome sequencing revealed significant downregulation of T cell differentiation pathways in P3, particularly Tfh-related genes such as , , and . Flow cytometry confirmed a marked reduction in circulating Tfh cells in P3. Western blot and immunofluorescence analyses demonstrated that the R848Efs*38 mutation impaired the conversion of p100 into p52 and disrupted nuclear translocation.
This study identifies novel mechanisms by which NF-κB2 mutations impair immune function. The R848Efs*38 mutation disrupts Tfh cell differentiation by interfering with p100 processing and reducing key Tfh-related transcription factors. These findings enhance our understanding of NF-κB2-related immunodeficiencies and their molecular underpinnings, contributing to the broader knowledge of immune regulation and potential therapeutic targets.
非经典NF-κB2信号通路对免疫调节至关重要，NF-κB2的致病性突变与常见可变免疫缺陷（CVID）、反复感染和自身免疫性疾病有关。滤泡辅助性T（Tfh）细胞在B细胞分化和抗体产生中起关键作用，但NF-κB2突变对Tfh细胞分化的影响仍不清楚。本研究调查了两种NF-κB2突变：c.1714G>A（p.A572T）和c.2540dupT（p.R848Efs*38）的临床和功能后果。
我们分析了三名携带NF-κB2突变患者的临床特征、免疫表型和内分泌特征。对患者3（P3）和五名健康供体的外周血单个核细胞（PBMC）进行转录组测序，以检查基因表达变化。流式细胞术定量Tfh细胞群体，实时定量聚合酶链反应（RT-qPCR）验证参与Tfh分化的基因表达。通过蛋白质免疫印迹法和免疫荧光法在HEK293T细胞中评估NF-κB2突变对p100加工和核转位的影响。
患者1（P1）表现出轻度临床特征，主要为哮喘，而患者3（P3）表现为严重免疫缺陷、反复肺部感染和激素缺乏。转录组测序显示P3中T细胞分化途径显著下调，尤其是与Tfh相关的基因，如 、 和 。流式细胞术证实P3中循环Tfh细胞明显减少。蛋白质免疫印迹法和免疫荧光分析表明，R848Efs*38突变损害了p100向p52的转化并破坏了核转位。
本研究确定了NF-κB2突变损害免疫功能的新机制。R848Efs*38突变通过干扰p100加工和减少关键的Tfh相关转录因子来破坏Tfh细胞分化。这些发现增进了我们对NF-κB2相关免疫缺陷及其分子基础的理解，有助于更广泛地了解免疫调节和潜在治疗靶点。
