The major source of endogenous prostaglandin D2 production is likely antigen-presenting cells. Localization of glutathione-requiring prostaglandin D synthetase in histiocytes, dendritic, and Kupffer cells in various rat tissues.
The major source of endogenous prostaglandin D2 production is likely antigen-presenting cells. Localization of glutathione-requiring prostaglandin D synthetase in histiocytes, dendritic, and Kupffer cells in various rat tissues.
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内源性前列腺素 D2 产生的主要来源可能是抗原呈递细胞。
作者：
Y. Urade;M. Ujihara;Y. Horiguchi;K. Ikai;O. Hayaishi
需要谷胱甘肽的 PGD 合成酶（催化各种外周组织中 PGD2 的主要形成）的细胞定位，通过使用对该酶具有特异性的多克隆抗体进行免疫过氧化物酶染色，在成年大鼠中进行了研究。尽管合成酶的 25 个 N 端氨基酸残基与几种大鼠谷胱甘肽 S-转移酶亚基的 25 个 N 端氨基酸残基有 56% 相同和 76% 相似，但该抗体仅与斑点印迹中的合成酶发生交叉反应，并且与迄今为止纯化的所有转移酶同工酶几乎完全失活。在对大鼠脾脏粗提物进行 SDS-PAGE 后的蛋白质印迹中，该抗体在与纯化酶相同的位置显示出单个阳性条带 (Mr = 26,000)。在脾脏、胸腺和小肠派尔氏结的许多组织细胞和/或树突状细胞中发现了阳性免疫细胞化学染色。在小肠和结肠绒毛固有层、胃粘膜下层和肝脏库普弗细胞中的此类细胞中也观察到免疫染色。免疫电镜证实该酶的免疫反应性分布在这些细胞的细胞质中。在脑、脊髓、肾、心脏、睾丸和骨骼肌中没有观察到此类免疫反应细胞。这些观察结果表明，PGD2 是由位于各种组织中这些类型的 APC 中的需要谷胱甘肽的 PGD 合成酶产生的，并且可能在决定免疫反应的进展中发挥关键作用。
The cellular localization of glutathione-requiring PGD synthetase, which catalyzes the predominant formation of PGD2 in various peripheral tissues, was investigated in adult rats by immunoperoxidase-staining with a polyclonal antibody specific for this enzyme. Although the 25 N-terminal amino acid residues of synthetase are 56% identical and 76% similar to those of several rat glutathione S-transferase subunits, the antibody cross-reacted only with synthetase in dot blotting and was nearly completely inactive with all transferase isozymes thus far purified. In Western blotting after SDS-PAGE of crude extracts of rat spleen, the antibody showed a single positive band at the same position as that of the purified enzyme (Mr = 26,000). The positive immunocytochemical stain was found in a number of histiocytes and/or dendritic cells in spleen, thymus, and Peyer's patch of intestine. The immunostain was also observed in such cells in lamina propria of the villus in small intestine and colon, in submucosal layer of stomach, and in Kupffer cells in liver. Immunoelectron microscopy confirmed that immunoreactivity of this enzyme was distributed in cytoplasm of those cells. Such immunoreactive cells were not observed in brain, spinal cord, kidney, heart, testis, and skeletal muscle. These observations suggest that PGD2 is produced by glutathione-requiring PGD synthetase localized in these types of APC in various tissues and may play a critical role in dictating the progression of immune responses.