The role of IDO/TTS mediated tryptophan metabolic pathway in patients with immune thrombocytopenia
10.3969/j.issn.1006-5725.2014.21.025
- VernacularTitle:IDO／TTS介导的色氨酸代谢途径在免疫性血小板减少症患者发病及治疗中的作用
- Author:
Qiujie CHEN
;
Yu ZENG
;
Yunlong GAO
;
Yan MA
;
Xinzhong WU
- Publication Type:Journal Article
- Keywords:
Immune thrombocytopenia;
Indoleamine 2,3-dioxygenase;
Tryptophanyl tRNA synthetase;
Dexamethasone
- From:
The Journal of Practical Medicine
2014;(21):3441-3444
- CountryChina
- Language:Chinese
-
Abstract:
Objective To discuss the role of indoleamine 2, 3-dioxygenas e (IDO) and tryptophanyl-tRNA synthetase (TTS) mediated tryptophan catabolism in immune thrombocytopenia (ITP) patients treated with high doses of dexamethasone through the expressions of IDO and TTS in T cells , and the concentrations of plasma kynurenine and tryptophan. Methods 20 newly diagnosed or relapse ITP patients were treated with 40 mg/d × 4 d dose of dexamethasone. The heparin anticoagulant blood samples were obtained before treatment and the 5th day after treatment. 20 healthy subjects were selected as the control group. The IDO and TTS expressions in CD4+and CD8+ T cells were analyzed by flow cytometry. The concentrations of plasma kynurenine and tryptophan were detected by liquid-mass spectrometry system. Results Compared with healthy controls group, the plasma tryptophan and kynurenine concentration and the ratio of Kyn/Trp were significantly elevated in ITP patients (P <0.05); the IDO expressions of CD4+ and CD8+ T cells in ITP patients were significantly lower than those in healthy controls (P < 0.05), but the TTS expressions were significantly higher (P < 0.05). The concentration of tryptophan in effective group was significantly lower than before treatment (P < 0.05), in contrast, the kynurenine concentration and the ratio of Kyn/Trp were significantly higher than before (P < 0.05). The expression of IDO in effective group were significantly higher than that before treatment (P < 0.05), conversely, the expression of TTS in effective group were significantly decreased (P < 0.05). No significant difference can be found in ineffective group. Conclusion IDO/TTS-mediated tryptophan catabolism pathway could indicate the onset of ITP. The sensitivity of ITP patients with high dose of dexamethasone treatment can be observed through the level of IDO and TTS.
