Chiba Takahito, Kanda Akira, Ueki Shigeharu, Ito Wataru, Kamada Yumiko, Oyamada Hajime, Saito Norihiro, Kayaba Hiroyuki, Chihara Junichi
Department of Clinical and Laboratory Medicine, Akita University School of Medicine, Akita, Japan.
Int Arch Allergy Immunol. 2006;141(3):300-7. doi: 10.1159/000095436. Epub 2006 Aug 28.
Prostaglandin D(2) (PGD(2)), a major prostanoid produced by activated mast cells, has long been implicated in allergic diseases. PGD(2) demonstrates its effects through two G-protein-coupled receptors, DP and CRTH2. The PGD(2)/CRTH2 system mediates chemotaxis of eosinophils, basophils, and Th2 cells, which are involved in the induction of allergic inflammation. Although recent studies have shown that the specific receptors for PGD(2), DP, and CRTH2 are expressed in various human tissues, the role of PGD(2) is unknown in human bronchial epithelial cells. In this study, we investigated the expression and function of CRTH2/DP on NCI-H(292) and NHBE cells.
The CRTH2/DP expression was examined by RT-PCR and flow-cytometric analysis. NCI-H(292) and NHBE cells were cultured in the presence of various stimulants. The resulting supernatants were measured by ELISA.
We demonstrated that PGD(2) induced production of IL-8 and GM-CSF in NCI-H(292) and NHBE cells. DK-PGD(2) (CRTH2 agonist) and latanoprost (FP, a prostaglandin F receptor, agonist) failed to augment the production of these cytokines. Pretreatment with ramatroban (CRTH2 antagonist) and AL8810 (FP antagonist) did not reduce the production of these cytokines. The PGD(2)-induced cytokine production was inhibited by pertussis toxin or specific inhibitors for MAP/ERK kinase (PD98059) and p38 MAP kinase (SB202190).
These results suggest that PGD(2) is a potent inducer of IL-8 and GM-CSF production with MAP/ERK and p38 MAP kinase activation, but this is independent of CRTH2 activation.
前列腺素D2（PGD2）是活化肥大细胞产生的主要类前列腺素，长期以来一直被认为与过敏性疾病有关。PGD2通过两种G蛋白偶联受体DP和CRTH2发挥作用。PGD2/CRTH2系统介导嗜酸性粒细胞、嗜碱性粒细胞和Th2细胞的趋化作用，这些细胞参与过敏性炎症的诱导。尽管最近的研究表明PGD2的特异性受体DP和CRTH2在各种人体组织中表达，但PGD2在人支气管上皮细胞中的作用尚不清楚。在本研究中，我们调查了CRTH2/DP在NCI-H292和NHBE细胞中的表达和功能。
通过逆转录聚合酶链反应（RT-PCR）和流式细胞术分析检测CRTH2/DP的表达。NCI-H292和NHBE细胞在各种刺激物存在的情况下进行培养。通过酶联免疫吸附测定（ELISA）测量所得上清液。
我们证明PGD2可诱导NCI-H292和NHBE细胞产生白细胞介素-8（IL-8）和粒细胞-巨噬细胞集落刺激因子（GM-CSF）。DK-PGD2（CRTH2激动剂）和拉坦前列素（FP，前列腺素F受体激动剂）未能增加这些细胞因子的产生。用雷马曲班（CRTH2拮抗剂）和AL8810（FP拮抗剂）预处理并未降低这些细胞因子的产生。PGD2诱导的细胞因子产生受到百日咳毒素或丝裂原活化蛋白激酶/细胞外信号调节激酶（MAP/ERK激酶）特异性抑制剂（PD98059）和p38丝裂原活化蛋白激酶（SB202190）的抑制。
这些结果表明，PGD2是一种通过MAP/ERK和p38丝裂原活化蛋白激酶激活而有效诱导IL-8和GM-CSF产生的诱导剂，但这与CRTH2激活无关。
