Table 1_Single-cell transcriptomics reveals systemic immune dysregulation in non-segmental vitiligo.xlsx

BackgroundNon-segmental vitiligo (NSV) is an autoimmune disorder characterized by irregular depigmented skin patches due to melanocyte loss, which causes considerable psychosocial burden. Although localized mechanisms underlying vitiligo pathogenesis have been studied extensively, investigations into peripheral blood mononuclear cells (PBMCs), key mediators of autoimmune diseases, remain limited.
MethodsTo address this gap, we performed single-cell RNA sequencing (scRNA-seq) on peripheral blood samples from 3 untreated patients with generalized, progressive non-segmental vitiligo (GP-NSV) and 3 healthy controls. Findings were validated using flow cytometry in an additional cohort of 7 GP-NSV patients and 30 controls. Computational analyses, including pseudotime trajectory reconstruction and pathway enrichment, were employed to characterize immune cell subsets and their functional states.
ResultsVitiligo patients exhibited striking heterogeneity in PBMC subsets. KLRC2+ NK cells were markedly reduced and enriched in tumor necrosis factor (TNF) and apoptotic signaling pathways, a finding further confirmed by flow cytometry. Pseudotime analysis indicated that NK cells underwent negative regulation of DNA metabolic processes alongside activation of granzyme-mediated programmed cell death. In addition, the frequency of FCGR3A+ Cytotoxic CD8+T cell was reduced, with enrichment in T cell activation and differentiation signatures. STAM+ regulatory T cells (Tregs) were increased, whereas EGR1+ B cells were decreased, both subsets showing enrichment in pathways linked to osteoclast differentiation and calcium ion metabolism, suggesting a potential role of calcium homeostasis dysregulation in disease pathogenesis.
ConclusionsThis study provides the single-cell atlas of PBMCs in GP-NSV, uncovering profound transcriptional and compositional alterations across multiple immune cell subsets in active vitiligo. These findings offer novel insights into systemic immune dysregulation in GP-NSV and pave the way for novel targeted therapeutic strategies.

背景 非节段性白癜风（non-segmental vitiligo, NSV）是一类自身免疫性疾病，以黑素细胞丢失导致的不规则色素脱失性皮肤斑块为特征，会给患者带来显著的社会心理负担。尽管白癜风发病的局部机制已得到广泛研究，但作为自身免疫疾病关键介导因子的外周血单个核细胞（peripheral blood mononuclear cells, PBMCs）的相关研究仍然有限。
方法 为填补这一研究空白，我们对3名未接受治疗的泛发性进展性非节段性白癜风（generalized, progressive non-segmental vitiligo, GP-NSV）患者及3名健康对照的外周血样本开展了单细胞RNA测序（single-cell RNA sequencing, scRNA-seq）。随后在包含7名GP-NSV患者与30名健康对照的额外队列中，通过流式细胞术（flow cytometry）对研究结果进行了验证。我们采用包括拟时间轨迹重构、通路富集分析在内的计算分析方法，对免疫细胞亚群及其功能状态进行了表征。
结果 白癜风患者的PBMC亚群呈现出显著的异质性。KLRC2+ NK细胞显著减少，且富集于肿瘤坏死因子（tumor necrosis factor, TNF）及凋亡信号通路，这一发现经流式细胞术进一步证实。拟时间分析显示，NK细胞在发生颗粒酶介导的程序性细胞死亡激活的同时，伴随DNA代谢过程的负向调控。此外，FCGR3A+ 细胞毒性CD8+T细胞的频率降低，且富集于T细胞活化与分化特征通路。STAM+ 调节性T细胞（regulatory T cells, Tregs）数量增加，而EGR1+ B细胞数量减少，这两个亚群均富集于与破骨细胞分化及钙离子代谢相关的通路，提示钙稳态失调可能在疾病发病机制中发挥潜在作用。
结论 本研究构建了GP-NSV患者外周血单个核细胞的单细胞图谱，揭示了活动性白癜风患者体内多个免疫细胞亚群存在显著的转录组与组成层面的改变。上述发现为GP-NSV的系统性免疫失调提供了全新的研究视角，并为新型靶向治疗策略的开发奠定了基础。