Kennedy Aisling, Ng Chin Teck, Biniecka Monika, Saber Tajvur, Taylor Cormac, O'Sullivan Jacintha, Veale Douglas J, Fearon Ursula
Dublin Academic Health Care, St. Vincent's University Hospital and The Conway Institute of Biomolecular and Biomedical Research, Dublin, Ireland.
Arthritis Rheum. 2010 Mar;62(3):711-21. doi: 10.1002/art.27287.
To assess blood vessel stability in inflammatory synovial tissue (ST) and to examine neural cell adhesion molecule (NCAM), oxidative DNA damage, and hypoxia in vivo.
Macroscopic vascularity and ST oxygen levels were determined in vivo in patients with inflammatory arthritis who were undergoing arthroscopy. Vessel maturity/stability was quantified in matched ST samples by dual immunofluorescence staining for factor VIII (FVIII)/alpha-smooth muscle actin (alpha-SMA). NCAM and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) were examined by immunohistochemistry. Angiogenesis was assessed in vitro, using human dermal endothelial cells (HDECs) in a Matrigel tube formation assay.
A significant number of immature vessels (showing no pericyte recruitment) was observed in tissue from patients with inflammatory arthritis (P < 0.001), in contrast to osteoarthritic and normal tissue, which showed complete recruitment of pericytes. Low in vivo PO(2) levels in the inflamed joint (median [range] 22.8 [3.2-54.1] mm Hg) were inversely related to increased macroscopic vascularity (P < 0.04) and increased microscopic expression of FVIII and alpha-SMA (P < 0.04 and P < 0.03, respectively). A significant proportion of vessels showed focal expression of NCAM and strong nuclear 8-oxodG expression, implicating a loss of EC-pericyte contact and increased DNA damage, levels of which were inversely associated with low in vivo PO(2) (P = 0.04 for each comparison). Circulating cells were completely negative for 8-oxodG. Exposure of HDEC to 3% O(2) (reflecting mean ST in vivo measurements) significantly increased EC tube formation (P < 0.05).
Our findings indicate the presence of unstable vessels in inflamed joints associated with hypoxia, incomplete EC-pericyte interactions, and increased DNA damage. These changes may further contribute to persistent hypoxia in the inflamed joint to further drive this unstable microenvironment.
评估炎症滑膜组织（ST）中的血管稳定性，并在体内检测神经细胞黏附分子（NCAM）、氧化性DNA损伤和缺氧情况。
对接受关节镜检查的炎症性关节炎患者进行体内宏观血管形成和ST氧水平测定。通过对VIII因子（FVIII）/α平滑肌肌动蛋白（α-SMA）进行双重免疫荧光染色，对匹配的ST样本中的血管成熟度/稳定性进行定量分析。通过免疫组织化学检测NCAM和8-氧代-7,8-二氢-2'-脱氧鸟苷（8-氧代dG）。在体外使用人真皮内皮细胞（HDEC）进行基质胶管形成试验来评估血管生成。
与骨关节炎和正常组织中显示周细胞完全募集不同，在炎症性关节炎患者的组织中观察到大量未成熟血管（未显示周细胞募集）（P < 0.001）。炎症关节内的体内低PO₂水平（中位数[范围]22.8 [3.2 - 54.1] mmHg）与宏观血管形成增加（P < 0.04）以及FVIII和α-SMA的微观表达增加（分别为P < 0.04和P < 0.03）呈负相关。相当比例的血管显示NCAM的局灶性表达和强烈的核8-氧代dG表达，这意味着内皮细胞-周细胞接触丧失和DNA损伤增加，其水平与体内低PO₂呈负相关（每次比较P = 0.04）。循环细胞的8-氧代dG呈完全阴性。将HDEC暴露于3% O₂（反映ST体内平均测量值）显著增加了内皮细胞管形成（P < 0.05）。
我们的研究结果表明，炎症关节中存在与缺氧、内皮细胞-周细胞相互作用不完全以及DNA损伤增加相关的不稳定血管。这些变化可能进一步导致炎症关节持续缺氧，从而进一步推动这种不稳定的微环境。
