scRNAseq for patients with immunodeficiency and HCs

The NFAT family of transcription factors plays central roles in adaptive immunity in murine models, however, their contribution to human immune homeostasis remains poorly defined. In a multigenerational pedigree, we identified three patients carrying germline biallelic missense variants in NFATC1, presenting with recurrent infections, hypogammaglobulinemia and decreased antibody responses. The compound heterozygous NFATC1 variants identified in the patients caused decreased stability and reduced binding of DNA and interacting proteins. We observed defects in early activation and proliferation of T and B cells from these patients, amenable to reconstitution upon genetic rescue. Following stimulation, T-cell activation and proliferation were impaired, reaching that of healthy controls with delay indicative of an adaptive capacity of the cells. Assessment of the metabolic capacity of patient T cells, revealed that NFATc1-dysfunction rendered T cells unable to engage in glycolysis following stimulation, although oxidative metabolic processes were intact. We hypothesized that NFATc1-mutant T cells could compensate for the energy deficit due to defective glycolysis by enhanced lipid metabolism as an adaptation, leading to a delayed, but not lost activation responses. Indeed, we observed increased 13C-labelled palmitate incorporation into citrate indicating higher fatty acid oxidation and we demonstrated that metformin and rosiglitazone improved patient T-cell effector functions. Collectively, enabled by our molecular dissection of NFATC1 mutations and extending the role of NFATc1 in human immunity beyond receptor signaling, and reveal evidence of metabolic plasticity in the context of impaired glycolysis observed in patient T cells to remedy delayed effector responses.EGA study EGAS00001007271

活化T细胞核因子（nuclear factor of activated T cells, NFAT）家族转录因子在小鼠模型的适应性免疫中发挥核心作用，然而其对人类免疫稳态的贡献仍未得到充分阐明。本研究通过一多世代家系，鉴定出3名携带活化T细胞核因子C1（NFATC1）基因生殖系双等位错义突变位点的患者，其临床表现为反复感染、低丙种球蛋白血症以及抗体应答能力下降。本次鉴定出的患者体内复合杂合型NFATC1突变可导致突变蛋白稳定性降低，以及其与DNA及互作蛋白的结合能力减弱。我们观察到上述患者的T细胞与B细胞在早期活化及增殖过程中存在缺陷，且此类缺陷可通过遗传拯救手段得到恢复。经体外刺激后，患者T细胞的活化与增殖过程均受到损伤，但其功能可随时间延迟逐步恢复至健康对照水平，提示该类细胞具备一定的适应性潜能。对患者T细胞代谢能力的评估结果显示，尽管氧化代谢过程仍保持完好，但NFATc1功能缺陷会导致T细胞在受刺激后无法正常激活糖酵解通路。据此我们提出假说：NFATc1突变型T细胞可通过增强脂质代谢以弥补糖酵解缺陷所引发的能量不足，以此作为一种适应性机制，最终使得细胞活化应答虽出现延迟但并未完全丧失。实验结果证实了该假说：我们观察到碳13标记的棕榈酸掺入柠檬酸的水平显著升高，提示脂肪酸氧化水平增强；同时我们证实二甲双胍与罗格列酮均可改善患者T细胞的效应功能。综上而言，本研究通过对NFATC1突变的分子解析，不仅拓展了NFATc1在人类免疫中的功能边界（使其不再局限于仅参与受体信号通路），同时证实了在患者T细胞糖酵解受损的背景下存在代谢可塑性现象，该可塑性可有效改善延迟出现的效应应答缺陷。欧洲基因组-表型组档案（European Genomephenome Archive, EGA）研究编号：EGAS00001007271