Department of Microbiology and Immunology, Medical School of Nantong University, Jiangsu, PR China.
Cell Immunol. 2010;266(1):32-9. doi: 10.1016/j.cellimm.2010.08.008. Epub 2010 Aug 31.
β-1,4-Galactosyltransferase-I (GalTI) is unusual among the galactosyltransferase family, which has two isoforms that differ only in the length of their cytoplasmic domains [1]. In this study, we found that both the long and short isoforms of GalTI were expressed in human monocyte-derived dendritic cells (MoDCs), and localized in the cytoplasm near nucleus and cytomembrane. The expression level of GalTI and cellular adhesion ability was increased when DCs continued to mature. We also demonstrated that the cellular adhesion ability of DCs was inhibited by α-lactalbumin (α-LA) via interference with cell surface GalTI function, suggesting that the adhesion ability was positively correlated with the expression of cell surface long GalTI. α-LA also could inhibit DC-T clustering and CD4(+) T cell proliferation. Collectively, the data suggests that GalTI might act as a key adhesion molecular participating in T cells-DCs contacts.
β-1,4-半乳糖基转移酶-I（GalTI）在半乳糖基转移酶家族中较为特殊，该家族有两种同工酶，仅在细胞质结构域的长度上存在差异[1]。本研究发现，GalTI 的长型和短型同工酶均在人单核细胞来源的树突状细胞（MoDC）中表达，并定位于靠近细胞核和细胞质膜的细胞质中。当 DC 持续成熟时，GalTI 的表达水平和细胞黏附能力增加。我们还证明，通过干扰细胞表面 GalTI 功能，α-乳白蛋白（α-LA）可抑制 DC 的细胞黏附能力，这表明黏附能力与细胞表面长型 GalTI 的表达呈正相关。α-LA 还可以抑制 DC-T 细胞簇形成和 CD4(+)T 细胞增殖。综上所述，数据表明 GalTI 可能作为一种关键的黏附分子，参与 T 细胞-DC 细胞的相互作用。
