Abstract：
BACKGROUND: Intracellular methotrexate polyglutamates (MTX-PGs) concentrations are measurable in red blood cells (RBCs) during MTX treatment. MTX-PG3 concentrations correlate with efficacy in patients with Crohn\'s disease (CD). Since RBCs are not involved in pathogenesis of CD and lack extended MTX metabolism, we determined MTX-PGs accumulation in peripheral blood mononuclear cells (PBMCs: effector cells) and intestinal mucosa (target cells) and compared those with RBCs as a potential more precise biomarker.
METHODS: In a multicentre prospective cohort study, blood samples of patients with CD were collected during the first year of MTX therapy. Mucosal biopsies were obtained from non-inflamed rectum and/or inflamed intestine. MTX-PGs concentrations in mucosa, PBMCs and RBCs were measured by liquid chromatography-tandem mass spectrometry.
RESULTS: From 80 patients with CD, a total of 27 mucosal biopsies, 9 PBMC and 212 RBC samples were collected. From 12 weeks of MTX therapy onwards, MTX-PG3 was the most predominant species (33%) in RBCs. In PBMCs, the distribution was skewed towards MTX-PG1 (48%), which accounted for an 18 times higher concentration than in RBCs. Long-chain MTX-PGs were highly present in mucosa: 21% of MTX-PGtotal was MTX-PG5. MTX-PG6 was measurable in all biopsies.
CONCLUSIONS: MTX-PG patterns differ between mucosa, PBMCs and RBCs of patients with CD.
METHODS: In a multicentre prospective cohort study, blood samples of patients with CD were collected during the first year of MTX therapy. Mucosal biopsies were obtained from non-inflamed rectum and/or inflamed intestine. MTX-PGs concentrations in mucosa, PBMCs and RBCs were measured by liquid chromatography-tandem mass spectrometry.
RESULTS: From 80 patients with CD, a total of 27 mucosal biopsies, 9 PBMC and 212 RBC samples were collected. From 12 weeks of MTX therapy onwards, MTX-PG3 was the most predominant species (33%) in RBCs. In PBMCs, the distribution was skewed towards MTX-PG1 (48%), which accounted for an 18 times higher concentration than in RBCs. Long-chain MTX-PGs were highly present in mucosa: 21% of MTX-PGtotal was MTX-PG5. MTX-PG6 was measurable in all biopsies.
CONCLUSIONS: MTX-PG patterns differ between mucosa, PBMCs and RBCs of patients with CD.
摘要：
背景：在MTX治疗期间，细胞内甲氨蝶呤聚谷氨酸（MTX-PGs）浓度在红细胞（RBC）中是可测量的。MTX-PG3浓度与克罗恩病（CD）患者的疗效相关。由于红细胞不参与CD的发病机制，缺乏延长的MTX代谢，我们测定了外周血单个核细胞(PBMC:效应细胞)和肠粘膜(靶细胞)中MTX-PGs的积累,并将其与RBC作为潜在的更精确的生物标志物进行了比较.
方法：在一项多中心前瞻性队列研究中，在MTX治疗的第一年收集CD患者的血样.从未发炎的直肠和/或发炎的肠获得粘膜活检。粘膜中的MTX-PG浓度，通过液相色谱-串联质谱法测量PBMC和RBC。
结果：来自80例CD患者，共进行了27次粘膜活检,收集9个PBMC和212个RBC样品。从MTX治疗12周开始，MTX-PG3是红细胞中最主要的物种(33%)。在PBMC中,分布偏向MTX-PG1（48%），比红细胞中的浓度高18倍。长链MTX-PGs高度存在于粘膜中:21%的MTX-PGtotal是MTX-PG5。MTX-PG6在所有活检中均可测量。
结论：粘膜之间的MTX-PG模式不同，CD患者的PBMC和RBC。
方法：在一项多中心前瞻性队列研究中，在MTX治疗的第一年收集CD患者的血样.从未发炎的直肠和/或发炎的肠获得粘膜活检。粘膜中的MTX-PG浓度，通过液相色谱-串联质谱法测量PBMC和RBC。
结果：来自80例CD患者，共进行了27次粘膜活检,收集9个PBMC和212个RBC样品。从MTX治疗12周开始，MTX-PG3是红细胞中最主要的物种(33%)。在PBMC中,分布偏向MTX-PG1（48%），比红细胞中的浓度高18倍。长链MTX-PGs高度存在于粘膜中:21%的MTX-PGtotal是MTX-PG5。MTX-PG6在所有活检中均可测量。
结论：粘膜之间的MTX-PG模式不同，CD患者的PBMC和RBC。
