Division of Otorhinolaryngology Head and Neck Surgery, Department of Sensory and Locomotor Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan.
Immun Inflamm Dis. 2021 Dec;9(4):1394-1405. doi: 10.1002/iid3.489. Epub 2021 Jul 19.
The chromosomal region 17q21 harbors the human orosomucoid-like 3 (ORMDL3) gene and has been linked to asthma and other inflammatory diseases. ORMDL3 is involved in the unfolded protein response (UPR), lipid metabolism, and inflammatory reactions. We investigated the effects of ORMDL3 overexpression in RBL-2H3 cells to determine the contribution of ORMDL3 to inflammatory disease development.
We generated ORMDL3 stably overexpressing RBL-2H3 cells to assess degranulation, transcriptional upregulation of interleukin-4 (IL-4), tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and mitogen-activated protein kinase (MAPK) phosphorylation via FcεRI. In addition, we examined the effects of ORMDL3 overexpression on thapsigargin (TG)-mediated proinflammatory cytokine transcription and UPR by monitoring MAPK, protein kinase-like endoplasmic reticulum kinase (PERK), and inositol-requiring enzyme 1 (IRE1) phosphorylation.
Overexpression of ORMDL3 enhanced IL-4, TNF-α, and MCP-1 expression after FcεRI cross-linking, whereas the sphingosine-1-phosphate (S1P) agonist FTY720 suppressed this enhancement. There was no significant difference in degranulation and MAPK phosphorylation via FcεRI-mediated activation between vector-transfected and ORMDL3-overexpressing cells. ORMDL3 overexpression accelerated TG-mediated PERK phosphorylation, while MAPK phosphorylation and proinflammatory cytokine expression showed no significant changes in ORMDL3-overexpressing cells.
Our findings suggest that ORMDL3 plays an important role in regulating proinflammatory cytokine expression via the S1P pathway and selectively affects the UPR pathway in mast cells.
染色体 17q21 区域含有人类粘蛋白样 3（ORMDL3）基因，与哮喘和其他炎症性疾病有关。ORMDL3 参与未折叠蛋白反应（UPR）、脂质代谢和炎症反应。我们研究了 ORMDL3 在 RBL-2H3 细胞中的过表达效应，以确定 ORMDL3 对炎症性疾病发展的贡献。
我们生成了 ORMDL3 稳定过表达的 RBL-2H3 细胞，以评估脱颗粒、白细胞介素 4（IL-4）、肿瘤坏死因子-α（TNF-α）、单核细胞趋化蛋白-1（MCP-1）和丝裂原激活蛋白激酶（MAPK）磷酸化的转录上调，通过 FcεRI。此外，我们通过监测 MAPK、蛋白激酶样内质网激酶（PERK）和肌醇需求酶 1（IRE1）磷酸化，研究了 ORMDL3 过表达对 thapsigargin（TG）介导的前炎症细胞因子转录和 UPR 的影响。
ORMDL3 过表达增强了 FcεRI 交联后的 IL-4、TNF-α 和 MCP-1 表达，而鞘氨醇-1-磷酸（S1P）激动剂 FTY720 抑制了这种增强。在 FcεRI 介导的激活中，载体转染和 ORMDL3 过表达细胞之间的脱颗粒和 MAPK 磷酸化没有显著差异。ORMDL3 过表达加速了 TG 介导的 PERK 磷酸化，而 MAPK 磷酸化和前炎症细胞因子表达在 ORMDL3 过表达细胞中没有显著变化。
我们的研究结果表明，ORMDL3 通过 S1P 途径在调节前炎症细胞因子表达中起重要作用，并选择性影响肥大细胞中的 UPR 途径。
