IDO/TTS介導(dǎo)的色氨酸代謝途徑在免疫性血小板減少癥患者發(fā)病及治療中的作用

應(yīng)伊麗　袁遠(yuǎn)

[摘要] 目的 探討IDO/TTS介導(dǎo)的色氨酸代謝途徑在免疫性血小板減少癥患者的發(fā)病和治療中的作用。 方法 選取2015年7月～2017年8月我院收治的36例免疫性血小板減少癥患者和36例來(lái)我院體檢的健康人為研究對(duì)象，分別為觀察組和對(duì)照組，觀察組給予地塞米松40 mg/d進(jìn)行治療，對(duì)照組不采取任何處理。通過(guò)液相-質(zhì)譜分析儀檢測(cè)血漿中犬尿氨酸（Kyn）和色氨酸（Trp）的濃度；通過(guò)流式細(xì)胞儀檢測(cè)T淋巴細(xì)胞中IDO和TTS的表達(dá)。 結(jié)果 與對(duì)照組相比，治療前免疫性血小板減少癥患者血漿中Kyn、Trp、Kyn/Trp的表達(dá)量較高，IDO的表達(dá)量較低，而TTS的表達(dá)量則明顯較高，差異有統(tǒng)計(jì)學(xué)意義（P<0.05）；觀察組經(jīng)有效治療后，患者血漿中Trp的濃度降低，而Kyn濃度及Kyn/Trp比值則明顯升高，差異有統(tǒng)計(jì)學(xué)意義（P<0.05）；患者IDO表達(dá)量明顯上升，而TTS的表達(dá)量則明顯下降，差異有統(tǒng)計(jì)學(xué)意義（P<0.05）。 結(jié)論 地塞米松對(duì)免疫性血小板減少癥患者療效顯著，主要通過(guò)IDO/TTS介導(dǎo)的色氨酸代謝途徑發(fā)揮作用，臨床可以通過(guò)監(jiān)測(cè)IDO、TTS的水平指導(dǎo)其治療。

[關(guān)鍵詞] IDO；TTS；免疫性血小板減少癥；發(fā)病；治療

[中圖分類號(hào)] R593.2 [文獻(xiàn)標(biāo)識(shí)碼] A [文章編號(hào)] 1673-9701（2017）36-0006-04

[Abstract] Objective To investigate the role of IDO/TTS-mediated tryptophan metabolic pathway in the pathogenesis and treatment of patients with immune thrombocytopenia. Methods A total of 36 patients with immune thrombocytopenia admitted in our hospital from July 2015 to August 2016 and 36 healthy volunteers who were in our hospital for physical examination were divided into observation group and control group. The observation group was given dexamethasone 40 mg/d. The control group was not given any treatment. Plasma concentrations of Kyn and Tryptophan were measured by liquid chromatography-mass spectrometry. The expression of IDO and TTS in T lymphocytes was detected by flow cytometry. Results Compared with that of the control group， the Kyn， Trp and Kyn/Trp plasma level in patients with pre-immune thrombocytopenia was higher， and the expression of IDO was lower， and the expression of TTS was significantly higher， and the difference was significant（P<0.05）. After effective treatment， the concentration of Trp in the plasma of the observation group was decreased， while the Kyn concentration and Kyn/Trp ratio of the observation group was significantly increased， and the difference was statistically significant（P<0.05）. The IDO expression level significantly increased， while the expression of TTS was significantly decreased， and the difference was statistically significant（P<0.05）. Conclusion Dexamethasone has a significant effect on patients with immune thrombocytopenia. It plays a role mainly through the tryptophan metabolic pathway mediated by IDO/TTS. Dexamethasone can monitor the level of IDO and TTS in order to guide its treatment. Clinically， IDO and TTS levels can be monitored to guide the treatment.

[Key words] IDO； TTS； Immune thrombocytopenia； Incidence； Treatment

免疫性血小板減少癥（primary immune thrombocytopenia，ITP）又稱特發(fā)性血小板減少性紫癜，屬于獲得性自身免疫性疾病[1，2]，是由于自身反應(yīng)性B和T細(xì)胞被自身血小板抗原所激活[3]，而發(fā)生免疫介導(dǎo)的單核巨噬細(xì)胞系統(tǒng)過(guò)度破壞被自身抗體致敏的血小板或免疫介導(dǎo)的巨核細(xì)胞抑制血小板的釋放，導(dǎo)致患者產(chǎn)生血小板減少或破壞的免疫性疾病[2，4]，主要表現(xiàn)為血小板減少、皮膚黏膜出血、乏力等癥狀[5]。地塞米松屬于腎上腺糖皮質(zhì)激素，具有抗炎、抗過(guò)敏、抗病毒的多種功效，主要用于治療嚴(yán)重過(guò)敏[6]、哮喘、皮膚病和慢性阻塞性肺部疾病[7]、結(jié)核病[8]、免疫性疾病[9，10]，作為治療免疫性血小板減少癥的首選藥物，其臨床有效率可達(dá)70%[11]。色氨酸（Trp）是細(xì)胞生存和周期進(jìn)展中的必須氨基酸，T細(xì)胞的周期進(jìn)程對(duì)細(xì)胞內(nèi)Trp含量很敏感，當(dāng)Trp濃度降低時(shí)，T細(xì)胞周期發(fā)生阻滯，T細(xì)胞的增殖會(huì)發(fā)生抑制[12]。……