1,25-(OH)2D3抑制脂多糖诱导的脐血CD4+T细胞IL-13和IL-17的表达

1,25-(OH)2D3 inhibits lipopolysaccharide-induced expression of interleukin-13 and interleukin-17 in cord blood CD4+T cells

摘要:

目的 本研究旨在探讨生命早期脂多糖(LPS)对脐血CD4⁺T细胞白介素-13(IL-13)和白介素-17(IL-17)表达的影响及1,25-(OH)₂D₃对其表达的干预作用,为维生素D的临床合理应用及其对哮喘等变态反应性疾病的防治提供理论依据。方法 选取顺产的足月新生儿12例,断脐后立即取胎盘端脐静脉血50 mL,采用密度梯度离心法分离脐血单个核细胞(CBMCs),磁珠分选CD4⁺T细胞后依据不同的处理方法分为空白刺激组、LPS(10 μg/mL)单独刺激组和LPS(10 μg/mL)+1,25-(OH)₂D₃(10^-8 mmol/L)共刺激组。培养72 h后采用双抗夹心酶联免疫吸附试验(ELISA)和Real-Time PCR分别检测培养上清液中IL-13和IL-17水平及CD4⁺T细胞中IL-13和IL-17 mRNA表达。结果 与空白刺激组相比,LPS单独刺激组培养上清液中IL-13和IL-17水平及CD4⁺T细胞中IL-13和IL-17 mRNA表达水平明显升高(均P<0.01),而1,25-(OH)₂D₃处理可降低其表达水平(均P<0.05),但仍高于空白刺激组(均P<0.01)。结论 LPS可促进脐血CD4⁺T细胞IL-13和IL-17的表达;1,25-(OH)₂D₃对于LPS诱导的脐血CD4⁺T细胞IL-13和IL-17表达具有抑制作用,提示1,25-(OH)₂D₃可能在变应原致敏的早期发挥一定保护作用。

Abstract:

Objective To study the effect of 1,25-(OH)₂D₃ on lipopolysaccharide (LPS)-induced expression of interleukin-13 (IL-13) and interleukin-17 (IL-17) in cord blood CD4⁺T cells, providing theoretical basis for clinical reasonable application of vitamin D and prevention of asthma and allergic diseases. Methods Mononuclear cells (MNCs) were isolated from umblilical cord blood (50 mL) of 12 normal eutocia term newborns by gravity centrifugation. CD4⁺T cells were isolated using magnetic beads, which was cultured with following three kinds of stimulus for 72 hours:. natural state (blank group), LPS (10 μg/mL)stimulation alone and LPS(10 μg/mL)+1,25-(OH)₂D₃ (10^-8 mmol/L)stimulation. Levels of IL-13 and IL-17 in the culture supernatant and mRNA expressions in cord blood CD4⁺T cells were detected using ELISA and real Time-PCR respectively. Results Compared with the blank group, levels of IL-13 and IL-17 in the culture supernatant and mRNA expression of IL-13 and IL-17 in the cord blood CD4⁺T cells increased in the LPS stimulation alone group (P<0.01). When co-stimulation of 1,25-(OH)₂D₃ with LPS, levels of IL-13 and IL-17 in the culture supernatant and mRNA expression of IL-13 and IL-17 in the cord blood CD4⁺T cells decreased compared with LPS-stimulated alone group (P<0.05), but remained higher than the blank group (P<0.01). Conclusions LPS can promote expression of IL-13 and IL-17 in cord blood CD4⁺T cells. 1,25-(OH)₂D₃ inhibits the expression of IL-13 and IL-17, suggesting that vitamin D intake may provide protective effects in the development of atopy-predisposing immune responses in early life.