de Jong T A, Semmelink J F, Bolt J W, Grasso C, Hoebe R A, Krawczyk P M, van Baarsen L G M
Department of Rheumatology & Clinical Immunology and Laboratory for Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.
Inflammatory Diseases, Amsterdam Institute for Infection and Immunity, Amsterdam, The Netherlands.
Clin Exp Immunol. 2025 Jan 21;219(1). doi: 10.1093/cei/uxaf029.
Cellular senescence, a state of proliferation arrest, is implicated in the pathogenesis of age-related diseases such as rheumatoid arthritis (RA). The pathogenesis of RA, characterized by immune dysregulation and systemic autoimmunity preceding clinical onset of disease, may involve early accumulation of senescent lymph node (LN) fibroblasts driving immune tolerance breakdown. This study aims to explore the hallmarks of senescence in LN fibroblasts during the earliest phases of RA and evaluate the effects of dasatinib. Human LN fibroblasts were isolated from inguinal LN needle biopsies from autoantibody-positive individuals at risk of developing RA (RA-risk individuals), RA patients, and seronegative healthy volunteers. Senescence hallmarks and the effects of dasatinib treatment were assessed using quantitative gene expression analysis, flow cytometry, microscopy, and live-cell imaging. Cell size, granularity, and autofluorescence were significantly greater in RA LN fibroblasts compared with controls. Altered gene expression of senescence-associated genes was observed in RA LN fibroblasts. Elevated senescence-associated β-galactosidase activity, more lipofuscin-positive granules, and DNA damage were observed in RA-risk and RA LN fibroblasts. Notably, RA(-risk) LN fibroblasts presented impaired DNA damage repair capacity. Dasatinib treatment significantly improved the size and ability of the LN fibroblast pool to repair DNA damage. We observed multiple senescence hallmarks in RA LN fibroblasts and, to a lesser extent, in RA-risk LN fibroblasts, which could be partially restored by senescent cell removal via dasatinib treatment. These findings suggest a role for senescent LN fibroblasts in RA pathogenesis and highlight the potential of dasatinib as a potential therapeutic intervention to mitigate senescence-associated defects in RA.
细胞衰老，一种增殖停滞状态，与类风湿性关节炎（RA）等年龄相关疾病的发病机制有关。RA的发病机制以疾病临床发作前的免疫失调和全身自身免疫为特征，可能涉及衰老的淋巴结（LN）成纤维细胞的早期积累，从而导致免疫耐受破坏。本研究旨在探索RA最早阶段LN成纤维细胞衰老的特征，并评估达沙替尼的作用。从有患RA风险的自身抗体阳性个体（RA风险个体）、RA患者和血清阴性健康志愿者的腹股沟LN针吸活检中分离出人LN成纤维细胞。使用定量基因表达分析、流式细胞术、显微镜检查和活细胞成像评估衰老特征和达沙替尼治疗的效果。与对照组相比，RA LN成纤维细胞的细胞大小、颗粒度和自发荧光明显更大。在RA LN成纤维细胞中观察到衰老相关基因的表达改变。在RA风险个体和RA LN成纤维细胞中观察到衰老相关β-半乳糖苷酶活性升高、更多脂褐素阳性颗粒和DNA损伤。值得注意的是，RA（-风险）LN成纤维细胞的DNA损伤修复能力受损。达沙替尼治疗显著改善了LN成纤维细胞池的大小和修复DNA损伤的能力。我们在RA LN成纤维细胞中观察到多种衰老特征，在RA风险LN成纤维细胞中观察到的程度较轻，通过达沙替尼治疗去除衰老细胞可部分恢复这些特征。这些发现表明衰老的LN成纤维细胞在RA发病机制中起作用，并突出了达沙替尼作为减轻RA中衰老相关缺陷的潜在治疗干预措施的潜力。
