Axial spondyloarthritis (Ax-SpA) is a chronic inflammatory disease that predominantly affects the axial joints and is most common in young men. However, the precise immune cell subset involved in Ax-SpA remains unclear. Our study characterized the periphery immune landscape of Ax-SpA patients before and after anti-TNFα treatment using single-cell transcriptomics and proteomics sequencing and elucidated the effects of anti-TNFα treatment at the single-cell level. First, we found that peripheral granulocytes and monocytes significantly increased in Ax-SpA patients. Second, we identified a more functional subtype of regulatory T cells, which was present in synovial fluid and increased in patients after treatment. Third, we identified a cluster of inflammatory monocyte subset with stronger inflammatory and chemotactic characteristics. A potential interaction between classical monocytes and granulocytes via the CXCL8/2-CXCR1/2 signaling pathway was observed, which decreased after treatment. Together, these results defined the complex expression profiles and advanced our understanding of the immune atlas in Ax-SpA patients before and after anti-TNFα treatment.

中轴型脊柱关节炎 (Ax-SpA) 是一种主要影响中轴关节的慢性炎症性疾病，最常见于年轻男性。然而，参与 Ax-SpA 的精确免疫细胞亚群仍不清楚。我们的研究利用单细胞转录组学和蛋白质组测序描述了 Ax-SpA 患者在抗 TNFα 治疗前后的外周免疫状况，并在单细胞水平阐明了抗 TNFα 治疗的效果。首先，我们发现 Ax-SpA 患者外周粒细胞和单核细胞显着增加。其次，我们发现了一种功能更强的调节性 T 细胞亚型，这种亚型存在于滑液中，并且在治疗后在患者体内增加。第三，我们鉴定了一组具有更强炎症和趋化特征的炎症单核细胞亚群。观察到经典单核细胞和粒细胞之间通过 CXCL8/2-CXCR1/2 信号通路的潜在相互作用，这种相互作用在治疗后减少。总之，这些结果定义了复杂的表达谱，并加深了我们对 Ax-SpA 患者抗 TNFα 治疗前后免疫图谱的理解。