Immune checkpoints have emerged as promising therapeutic targets for autoimmune diseases. However, the specific roles of immune checkpoints in the pathophysiology of ankylosing spondylitis (AS) remain unclear. Hip ligament samples were obtained from two patient groups: those with AS and femoral head deformity, and those with femoral head necrosis but without AS, undergoing hip arthroplasty. Label-Free Quantification (LFQ) Protein Park Analysis was used to identify the protein composition of the ligaments. Peripheral blood samples of 104 AS patients from public database were used to validate the expression of key proteins. KEGG, GO, and GSVA were employed to explore potential pathways regulated by immune checkpoints in AS progression. xCell was used to calculate cell infiltration levels, LASSO regression was applied to select key cells, and the correlation between immune checkpoints and immune cells was analyzed. Drug sensitivity analysis was conducted to identify potential therapeutic drugs targeting immune checkpoints in AS. The expression of key genes was validated through immunohistochemistry (IHC). HLA-DMB and HLA-DPA1 were downregulated in the ligaments of AS and this has been validated through peripheral blood datasets and IHC. Significant differences in expression were observed in CD8 + Tcm, CD8 + T cells, CD8 + Tem, osteoblasts, Th1 cells, and CD8 + naive T cells in AS. The infiltration levels of CD8 + Tcm and CD8 + naive T cells were significantly positively correlated with the expression levels of HLA-DMB and HLA-DPA1. Immune cell selection using LASSO regression showed good predictive ability for AS, with AUC values of 0.98, 0.81, and 0.75 for the three prediction models, respectively. Furthermore, this study found that HLA-DMB and HLA-DPA1 are involved in Th17 cell differentiation, and both Th17 cell differentiation and the NF-kappa B signaling pathway are activated in the AS group. Drug sensitivity analysis showed that AS patients are more sensitive to drugs such as doramapimod and GSK269962A. Immune checkpoints and immune cells could serve as avenues for exploring diagnostic and therapeutic strategies for AS.

中文翻译：

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免疫检查点与免疫细胞在强直性脊柱炎诊治中联合作用的探索：强直性脊柱炎免疫检查点的初步研究


免疫检查点已成为自身免疫性疾病有希望的治疗靶点。然而，免疫检查点在强直性脊柱炎（AS）病理生理学中的具体作用仍不清楚。髋关节韧带样本取自两个患者组：患有 AS 和股骨头畸形的患者组，以及股骨头坏死但无 AS 且接受髋关节置换术的患者组。无标记定量（LFQ）蛋白质公园分析用于鉴定韧带的蛋白质组成。使用公共数据库中 104 名 AS 患者的外周血样本来验证关键蛋白的表达。采用 KEGG、GO 和 GSVA 来探索 AS 进展中免疫检查点调节的潜在途径。使用xCell计算细胞浸润水平，应用LASSO回归选择关键细胞，分析免疫检查点与免疫细胞的相关性。进行药物敏感性分析以确定针对 AS 免疫检查点的潜在治疗药物。通过免疫组织化学（IHC）验证关键基因的表达。 HLA-DMB 和 HLA-DPA1 在 AS 韧带中下调，这一点已通过外周血数据集和 IHC 得到验证。 AS 中 CD8 + Tcm、CD8 + T 细胞、CD8 + Tem、成骨细胞、Th1 细胞和 CD8 + 初始 T 细胞的表达存在显着差异。 CD8 + Tcm和CD8 + naive T细胞的浸润水平与HLA-DMB和HLA-DPA1的表达水平呈显着正相关。使用 LASSO 回归的免疫细胞选择对 AS 具有良好的预测能力，三个预测模型的 AUC 值分别为 0.98、0.81 和 0.75。 此外，本研究发现HLA-DMB和HLA-DPA1参与Th17细胞分化，并且在AS组中Th17细胞分化和NF-κB信号通路均被激活。药物敏感性分析显示，AS患者对doramapimod、GSK269962A等药物更为敏感。免疫检查点和免疫细胞可以作为探索 AS 诊断和治疗策略的途径。