Division of Allergy, Immunology and Rheumatology, Buddhist Dalin Tzu Chi General Hospital, Taiwan.
Clin Exp Immunol. 2013 Jul;173(1):47-57. doi: 10.1111/cei.12089.
Ankylosing spondylitis (AS) is a chronic inflammatory disorder characterized by dysregulated T cells. We hypothesized that the aberrant expression of microRNAs (miRNAs) in AS T cells involved in the pathogenesis of AS. The expression profile of 270 miRNAs in T cells from five AS patients and five healthy controls were analysed by real-time polymerase chain reaction (PCR). Thirteen miRNAs were found potentially differential expression. After validation, we confirmed that miR-16, miR-221 and let-7i were over-expressed in AS T cells and the expression of miR-221 and let-7i were correlated positively with the Bath Ankylosing Spondylitis Radiology Index (BASRI) of lumbar spine in AS patients. The protein molecules regulated by miR-16, miR-221 and let-7i were measured by Western blotting. We found that the protein levels of Toll-like receptor-4 (TLR-4), a target of let-7i, in T cells from AS patients were decreased. In addition, the mRNA expression of interferon (IFN)-γ was elevated in AS T cells. Lipopolysaccharide (LPS), a TLR-4 agonist, inhibited IFN-γ secretion by anti-CD3(+) anti-CD28 antibodies-stimulated normal T cells but not AS T cells. In the transfection studies, we found the increased expression of let-7i enhanced IFN-γ production by anti-CD3(+) anti-CD28(+) lipopolysaccharide (LPS)-stimulated normal T cells. In contrast, the decreased expression of let-7i suppressed IFN-γ production by anti-CD3(+) anti-CD28(+) LPS-stimulated AS T cells. In conclusion, we found that miR-16, miR-221 and let-7i were over-expressed in AS T cells, but only miR-221 and let-7i were associated with BASRI of lumbar spine. In the functional studies, the increased let-7i expression facilitated the T helper type 1 (IFN-γ) immune response in T cells.
强直性脊柱炎（AS）是一种慢性炎症性疾病，其特征为 T 细胞失调。我们假设 AS T 细胞中异常表达的 microRNAs（miRNAs）参与了 AS 的发病机制。通过实时聚合酶链反应（PCR）分析了来自 5 名 AS 患者和 5 名健康对照者 T 细胞中的 270 种 miRNA 的表达谱。发现有 13 种 miRNA 可能存在差异表达。经过验证，我们确认 miR-16、miR-221 和 let-7i 在 AS T 细胞中过度表达，并且 miR-221 和 let-7i 的表达与 AS 患者的腰椎 Bath 强直性脊柱炎放射学指数（BASRI）呈正相关。通过 Western blot 测量了由 miR-16、miR-221 和 let-7i 调节的蛋白质分子。我们发现，AS 患者 T 细胞中 let-7i 的靶标 Toll 样受体 4（TLR-4）的蛋白水平降低。此外，AS T 细胞中干扰素（IFN）-γ的 mRNA 表达升高。脂多糖（LPS），一种 TLR-4 激动剂，可抑制抗 CD3（+）抗 CD28（+）抗体刺激的正常 T 细胞但不抑制 AS T 细胞分泌 IFN-γ。在转染研究中，我们发现 let-7i 的表达增加增强了抗 CD3（+）抗 CD28（+）脂多糖（LPS）刺激的正常 T 细胞中 IFN-γ 的产生。相反，let-7i 的表达降低抑制了抗 CD3（+）抗 CD28（+）LPS 刺激的 AS T 细胞中 IFN-γ 的产生。总之，我们发现 miR-16、miR-221 和 let-7i 在 AS T 细胞中过度表达，但只有 miR-221 和 let-7i 与腰椎 BASRI 相关。在功能研究中，let-7i 表达的增加促进了 T 辅助细胞 1（IFN-γ）免疫反应。
