Misago M, Tsukada J, Fukuda M N, Eto S
Laboratory of Clinical Hematology, School of Health Sciences, University of Occupational and Environmental Health, Kitakyushu, 807-8555, Japan.
Biochem Biophys Res Commun. 2000 Mar 5;269(1):219-25. doi: 10.1006/bbrc.2000.2269.
The effects of the N-linked oligosaccharide inhibitors swainsonine and N-butyldeoxynojirimycin (NB-DNJ) on granulopoiesis was investigated using human bone marrow cells in in vitro liquid and agar cultures. The addition of the inhibitors into cultures containing granulocyte colony-stimulating factor (G-CSF) suppressed maturation from myelocytes into mature neutrophils. Swainsonine did not induce apoptosis, but NB-DNJ induced considerable apoptosis, especially in the presence of G-CSF. This result indicated that the decrease of mature neutrophils by swainsonine was not because of cell degeneration. In the case of NB-DNJ, it was thought to be because of both maturation suppression and apoptosis. In a colony-forming unit-granuloid (CFU-G) colony assay, the number of colonies was increased in the presence of the inhibitors, but the morphology of colonies was predominantly compact, or immature. The inhibitors also suppressed the expressions of mRNAs of CCAAT/enhancer binding protein epsilon (C/EBPepsilon) and G-CSF receptor as markers of terminal neutrophil maturation. These findings suggested that the incompleteness of N-linked oligosaccharide leads to the suppression of terminal neutrophil maturation.
利用人骨髓细胞在体外液体和琼脂培养中研究了N-连接寡糖抑制剂苦马豆素和N-丁基脱氧野尻霉素（NB-DNJ）对粒细胞生成的影响。将抑制剂添加到含有粒细胞集落刺激因子（G-CSF）的培养物中会抑制髓细胞向成熟中性粒细胞的成熟过程。苦马豆素不会诱导细胞凋亡，但NB-DNJ会诱导大量细胞凋亡，尤其是在存在G-CSF的情况下。这一结果表明，苦马豆素导致成熟中性粒细胞减少并非由于细胞变性。就NB-DNJ而言，认为是由于成熟抑制和细胞凋亡两者所致。在粒系集落形成单位（CFU-G）集落测定中，在存在抑制剂的情况下集落数量增加，但集落形态主要为致密或不成熟。这些抑制剂还抑制了CCAAT/增强子结合蛋白ε（C/EBPε）和G-CSF受体的mRNA表达，它们是终末中性粒细胞成熟的标志物。这些发现提示N-连接寡糖的不完整导致终末中性粒细胞成熟的抑制。
