Establishment and identification of a human megakaryocytic cell line with low Ley expression / 中国输血杂志

【Objective】 To establish a stable human megakaryocytic cell line with low expression of Ley antigen to further study the role of Ley on activation of platelets. 【Methods】 The expression level of the Ley antigen in a human megakaryocytic cell line, DAMI, was determined using Western Blot and flow cytometry. The expression level of genes that encode fucosyltransferase (FUTs), which was involved in the biosynthesis of Ley antigen, was also determined to identify the candidate genes to be knocked out. The candidate FUT gene was knocked out via a CRISPR/Cas 9 gene knockout system and cells with low Ley antigen expression were sorted by flow cytometry. The sorted cell line was cultured and characterized. 【Results】 The Ley was expressed intensively on DAMI cell. FUT1 and FUT4 mRNA was expressed relatively higher, both may be key enzymes for the biosynthesis of the Ley antigen. In the DAMI cell line with the knockout of FUT1 gene, the expression of the Ley adntigen was remarkedly reduced, while cell proliferation was not affected compared to the wildtype control cells. 【Conclusions】 Since various FUTs contributes to the biosynthesis of the Ley antigen, the knockout of the primary one of them cannot totally block its biosynthesis, but only reduce its expression. In this study, a stable FUT gene knockout human megakaryocyticcell line is established using CRISPR/Cas 9 technology, which provides basis for the study of the impact of the Ley antigen on platelet functions.

Effect and mechanism of terminal fucosylation inhibitor on ciclosporin-induced renal epithelial-mesenchymal transition / 器官移植

Objective To evaluate the effect and mechanism of terminal fucosylation inhibitor 2-deoxy-D-galactose (2-D-gal) on ciclosporin (CsA)-induced renal epithelial-mesenchymal transition (EMT). Methods Fifteen male C57BL/6 mice aged 8-10 weeks were randomly and evenly divided into the control group (Ctrl group), CsA group and CsA+2-D-gal group (n=5). The expression levels of fucosyltransferase 1 (FUT1), EMT-associated proteins including E-cadherin, Vimentin, α-smooth muscle actin (α-SMA) in the kidney tissues of the Ctrl and CsA groups were detected by Western blot. The expression levels of terminal fucose in the kidney tissues of Ctrl and CsA groups were determined by immunofluorescence. The renal fibrosis of mice in each group was evaluated by Masson staining. The blood urea nitrogen and serum creatinine levels of mice in each group were detected. The in vitro EMT model of renal tubular epithelial cell HK2 was induced by CsA. HK2 cells were stimulated with 0, 2.5, 5.0 and 10.0 μmol/L CsA for 24 h, respectively. In addition, HK2 cells were divided into the Ctrl, 2-D-gal, CsA and CsA+2-D-gal groups. The morphology of HK2 cells after stimulation with different concentrations of CsA and in each group was observed. The expression levels of FUT1, E-cadherin, Vimentin and α-SMA in HK2 cells after stimulation with different concentrations of CsA and in each group were detected by Western blot. The expression level of terminal fucose in HK2 cells of the Ctrl and CsA groups was measured by immunofluorescence. Results Compared with the Ctrl group, the relative expression of E-cadherin protein was down-regulated, those of FUT1, Vimentin and α-SMA proteins were up-regulated (all P < 0.05), and that of terminal fucose in the mouse kidney tissues was up-regulated in the CsA group. Compared with the Ctrl group, the blood urea nitrogen and serum creatinine levels in the CsA and CsA+2-D-gal groups were up-regulated (all P < 0.05). Compared with the CsA group, the blood urea nitrogen and serum creatinine levels in the CsA+2-D-gal group were down-regulated (both P < 0.05). Compared with the Ctrl group, the collagen fiber deposition was increased and the relative expression of α-SMA protein was up-regulated in the mouse kidney tissues of CsA and CsA+2-D-gal groups (all P < 0.05). Compared with the CsA group, the collagen fiber deposition was decreased and the relative expression of α-SMA protein in the mouse kidney tissues was down-regulated in the CsA+2-D-gal group (both P < 0.05). With the increase of CsA concentration, the morphology of HK2 cells gradually became longer and thinner from original normal cobblestone shape, the relative expression levels of FUT1, Vimentin and α-SMA protein in HK2 cells were up-regulated, and that of E-cadherin protein was down-regulated in a concentration-dependent manner. Compared with the Ctrl group, the expression level of terminal fucose of HK2 cells was up-regulated in the CsA group. After CsA treatment combined with 2-D-gal intervention, the morphology of HK2 cells in the CsA+2-D-gal group was restored to resemble that of normal HK2 cells. Compared with the CsA group, the relative expression of E-cadherin protein in HK2 cells was up-regulated, whereas those of Vimentin and α-SMA proteins were down-regulated in the CsA+2-D-gal group (all P < 0.05). Conclusions CsA may induce EMT both in vivo and in vitro, and the terminal fucosylation is increased. 2-D-gal may inhibit CsA-induced EMT by suppressing the terminal fucosylation.

Association of ulcerative colitis with FUT2 and FUT3 polymorphisms and their expression in Chinese patients / 解放军医学杂志

Objective To explore the association of genetic polymorphism of fucosyltransferase (FUT) 2 and FUT3 and expression of Lewis antigen with ulcerative colitis (UC) in Chinese Zhejiang Han population.Methods We genotyped FUT2 (rs281377, rs1047781 and rs601338) and FUT3 (rs28362459, rs3745635 and rs3894326) in 485 UC patients and 580 healthy controls using SNaPshot. By immunohistochemistry method, we also evaluated expression of Lewis a and b antigens in the sigmoid colon of 10 UC patients and 10 patients with benign colonic polyps.Results The frequencies of mutant allele (A) and genotype (GA+AA) in FUT3 rs3745635 were higher in UC patients than in controls (P=0.016, 95%CI 1.339-1.699;P=0.038, 95%CI 1.330-1.742, respectively). Stratified analyses revealed that the frequencies of mutant allele (G) and genotype (TG+GG) of FUT3 rs28362459 were significantly lower in patients with extensive colitis than in those with distal colitis (P=0.001, 95%CI 0.567-0.786;P<0.001, 95%CI 0.503-0.742, respectively). Similar conclusions were drawn for the mutant allele (A) and genotype (GA+AA) of FUT3 rs3745635 in patients with extensive colitis compared to those with distal colitis (P=0.011, 95%CI 0.621-0.900;P=0.006, 95%CI 0.553-0.845, respectively). Although expression of Lewis b antigen in the sigmoid colon did not differ between UC patients and controls, Lewis a antigen expression was higher in the crypt epithelium of both inflammatory and non-inflammatory sigmoid colon of UC patients than in controls (P=0.028).Conclusion Polymorphisms of FUT3 and expression level of Lewis a antigen might be associated with UC.

Effects of Neutralization by Soluble ABH Antigens Produced by Transplanted Kidneys From ABO-Incompatible Secretor Donors

BACKGROUND: Grafts survive despite blood group antigens on the transplant being continuously exposed to antibodies in the blood of recipients in ABO-incompatible kidney transplantation (ABOi KT), owing to the mechanism of accommodation. We analyzed the immunodynamics of soluble ABH antigens in allografts from secretor donors and the influence of such immunodynamics on accommodation and subsequent graft survival in ABOi KT. METHODS: The genotype of a known human β-galactoside α-1,2-fucosyltransferase gene (FUT2), which determines soluble ABH antigen secretor status, was established in 32 donors for ABOi KT at the Severance Hospital, from June 2010 to July 2015. Clinical outcomes of recipients, such as anti-A/B antibody titer change, renal function, and graft survival, were evaluated. RESULTS: Twenty-five donors were secretors (78.1%), and seven were nonsecretors (21.9%). The frequency of anti-A/B IgG or IgM antibody titer elevation or reduction post-transplantation was not significantly related to donor secretor status. However, IgM titer was rapidly reduced in recipients transplanted from nonsecretor donors (P=0.01), which could be explained by the lack of absorption effect of soluble antigens, enhancing the binding of antibodies to antigens in the allografts. Interestingly, soluble ABH antigens did not affect rejection-free graft survival, which may be due to the nature of β-galactoside α-1,2-fucosyltransferase. CONCLUSIONS: Soluble ABH antigens produced by transplanted kidneys from secretor donors played a role in inducing accommodation within three months of KT through neutralization; however, major graft outcomes were not affected.

α1, 6-fucosyltransferase and tumor: Recent progress / 第二军医大学学报

Core fucose glycosylation catalyzed by α1, 6-fucosetransferase(Fut8) is an important way for protein post-translational modification and functional regulation; it directly influences a series of biological characteristics of cells and is always seen under some pathological conditions. This paper reviews the recent studies on the regulation, biological function of Fut8 and its relationship with different kinds of tumors.

Biosynthesis of eukaryotic cell surface glycosphingolipids using solubilized glycosyltransferases.

Two fucsyltransferases (FucT-2 and FucT-3) have been solubilized from Golgi-rich membrane fraction of bovine spleen, using a cationic detergent. FucT-3 was distinguished from FucT-2 by comparing their kinetic parameters and heat stability. FucT-2 and FucT-3 lost activity (85 %) and (5 %), respectively, when heated at 55°C for 10 sec. Two galactosyltransferases (GalT-3 and GalT-4) and two sialyltransferases (SAT-2 and SAT-3) have also been solubilized from embryonic chicken brain membranes using nonionic detergents. Affinity chromatography and microisoelectric focusing were used to separate these enzymes into functionally pure fractions. Anomeric and positional linkages in some of the products (LM1 and LD1c) have also been established. The terminal NeuAc(α2–8) linkage in GD3 and LD1c was established by identification of the partially methylated penultimate [Ac-14C]sialic acid.