血管活性肠肽对肺炎支原体诱导A549细胞分泌白细胞介素-8的影响

Secretion of interleukin-8 in A549 cells infected with Mycoplasma pneumoniae and its inhibition by vasoactive intestinal peptide in vitro

目的研究血管活性肠肽对肺炎支原体体外诱导人肺上皮细胞癌细胞株(A549细胞)产生细胞因子白细胞介素-8(IL-8)水平的影响。方法将A549细胞与不同感染复数和不同刺激时间的Mp共同孵育,用ELISA法检测细胞培养上清液中IL-8的含量;用不同浓度VIP作用于不同Mp感染复数的A549细胞,并取不同培养时间的细胞上清液,检测其中IL-8的含量。结果 A549细胞经Mp刺激后,IL-8的产生水平明显高于对照组(P<0.05),且IL-8的产生水平对Mp的感染复数和感染时间具有依赖性。VIP在一定程度上可抑制Mp诱导的A549细胞IL-8的产生(P<0.05)。结论 Mp可诱导A549细胞产生炎性细胞因子IL-8,VIP可有效降低Mp诱导的IL-8的产生,有望成为Mp感染新的免疫治疗方法。

Objective To investigate the effect of interleukin-8 （IL-8） production in A549 cells which were triggered with My- coplasma pneumoniae（Mp） and to observe the effect on the expression of IL-8 protein treated with vasoactive intestinal peptide（VIP）. Methods Enzyme-linked immunosorbent assay（ELISA） was adopted to detect the expression of IL-8 protein in the cell culture supernatants of A549 cells which were trigged with Mp of different multiplicity of infection （MOI）and different time. And the same technique was used to detect the production of IL-8 in the cells treated with different density of VIP. Results Mp could significantly increase the expression of IL-8 in the cell culture supernatants of A549 cells（P 〈 O. 05）. And the level of production of IL-8 depended on the MOI and time. VIP could significantly inhibit the production of IL-8 （P 〈 0.05 ）. Conclusions Mp may induce the A549 ceils to produce proinflammatory cytokine IL-8. VIP could significantly reduce the production of IL-8. VIP is hopeful to be a new means for treatment of Mp infection VIP.