Swamynathan Sudha, Loughner Chelsea L, Swamynathan Shivalingappa K
Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, USA.
Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, USA; Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, USA; McGowan Institute of Regenerative Medicine, University of Pittsburgh, USA; Fox Center for Vision Restoration, University of Pittsburgh School of Medicine, Pittsburgh, USA.
Exp Eye Res. 2017 Nov;164:118-128. doi: 10.1016/j.exer.2017.08.007. Epub 2017 Aug 10.
Previously, we have reported that the Secreted Ly6/uPAR related protein-1 (SLURP1) serves an important immunomodulatory function in the ocular surface. Here, we examine the involvement of SLURP1 in regulating corneal angiogenic privilege. Slurp1 expression detected by QPCR, immunoblots and immunofluorescent stain, was significantly decreased in mouse corneas subjected to alkali burn-induced corneal neovascularization (CNV). Addition of exogenous SLURP1 (6XHis-tagged, E. coli expressed and partially purified using Ni-ion columns) significantly suppressed the tumor necrosis factor-α (TNF-α)-stimulated human umbilical cord vascular endothelial cell (HUVEC) tube formation. SLURP1 suppressed the HUVEC tube length, tube area and number of branch points, without affecting their viability and/or proliferation. Exogenous SLURP1 in HUVEC also suppressed the TNF-α-induced (i) interleukin-8 (IL-8) and TNF-α production, (ii) adhesion to different components of the extracellular matrix, (iii) migration, and (iv) nuclear localization of NFκB. Together, these results demonstrate that SLURP1 suppresses HUVEC tube formation by blocking nuclear translocation of NFκB, and suggest a potential role for SLURP1 in promoting corneal angiogenic privilege.
此前，我们曾报道分泌型Ly6/uPAR相关蛋白-1（SLURP1）在眼表发挥重要的免疫调节功能。在此，我们研究了SLURP1在调节角膜血管生成特权中的作用。通过定量聚合酶链反应（QPCR）、免疫印迹和免疫荧光染色检测发现，在遭受碱烧伤诱导角膜新生血管形成（CNV）的小鼠角膜中，Slurp1表达显著降低。添加外源性SLURP1（6X组氨酸标签，大肠杆菌表达并用镍离子柱部分纯化）可显著抑制肿瘤坏死因子-α（TNF-α）刺激的人脐静脉血管内皮细胞（HUVEC）管形成。SLURP1可抑制HUVEC管长度、管面积和分支点数量，而不影响其活力和/或增殖。HUVEC中的外源性SLURP1还可抑制TNF-α诱导的（i）白细胞介素-8（IL-8）和TNF-α产生，（ii）对细胞外基质不同成分的黏附，（iii）迁移，以及（iv）核因子κB（NFκB）的核定位。总之，这些结果表明SLURP1通过阻断NFκB的核转位来抑制HUVEC管形成，并提示SLURP1在促进角膜血管生成特权方面具有潜在作用。
