Department of Orthopaedics, Affiliated Hospital of Nantong University, People's Republic of China.
Clin Exp Med. 2011 Sep;11(3):147-54. doi: 10.1007/s10238-010-0121-6. Epub 2010 Dec 16.
β1,4-galactosyltransferase-I (β1,4-GalT-I), which is one of the best-studied glycosyltransferases, plays a key role in the synthesis of selectin ligands such as sialyl Lewis (sLe(x)) and sulfated sLe(x). Previous studies showed that inflammatory responses of β1,4-GalT-I-deficient mice were impaired because of the defect in selectin-ligand biosynthesis. However, the expression of β1,4-GalT-I and its biological function in rheumatoid arthritis (RA) remain to be elucidated. The mRNA and protein expression of β1,4-GalT-I increased in synovial tissue of the RA group compared with the Normal group at 10d and 15d after collagen-induced. Double staining indicated β1,4-GalT-I overlapped with macrophage-like synoviocytes (MLSs), fibroblast-like synoviocytes (FLSs), neutrophils and tumor necrosis factor-α (TNF-α). Moreover, β1,4-GalT-I mRNA in FLSs in vitro was affected in a dose- and time-dependent manner in response to TNF-α stimulation. ELISA revealed that expression of TNF-α was attenuated in FLSs in vitro treated with β1,4-GalT-I-Ab. We therefore suggest that β1,4-GalT-I may play an important role in the inflammation process of RA synovial tissue, which would provide the foundation for further researching into the concrete mechanism of β1,4-GalT-I in RA.
β1,4-半乳糖基转移酶-I（β1,4-GalT-I）是研究最为深入的糖基转移酶之一，在选择素配体（如唾液酸化路易斯（sLe(x)）和硫酸化 sLe(x））的合成中发挥关键作用。先前的研究表明，由于选择素配体生物合成缺陷，β1,4-GalT-I 缺陷小鼠的炎症反应受损。然而，β1,4-GalT-I 在类风湿关节炎（RA）中的表达及其生物学功能仍有待阐明。与正常组相比，在胶原诱导后 10d 和 15d，RA 组的滑膜组织中β1,4-GalT-I 的 mRNA 和蛋白表达增加。双染色表明β1,4-GalT-I 与巨噬细胞样滑膜细胞（MLSs）、成纤维样滑膜细胞（FLSs）、中性粒细胞和肿瘤坏死因子-α（TNF-α）重叠。此外，体外 TNF-α刺激下，FLSs 中β1,4-GalT-I mRNA 呈剂量和时间依赖性变化。ELISA 显示，体外用β1,4-GalT-I-Ab 处理的 FLSs 中 TNF-α的表达减弱。因此，我们认为β1,4-GalT-I 可能在 RA 滑膜组织的炎症过程中发挥重要作用，这将为进一步研究β1,4-GalT-I 在 RA 中的具体机制提供基础。
