黄曲霉毒素B_(1)对卵白蛋白激发人外周血嗜碱性白血病细胞(KU812)脱颗粒的影响

Effects of aflatoxin B_(1) on the degranulation of ovalbumin-sensitized human peripheral blood basophilic leukemia cells(KU812 cells)

目的 研究黄曲霉毒素B_(1)(aflatoxin B_(1), AFB_(1))暴露对鸡蛋过敏原卵白蛋白(ovalbumin, OVA)激发人外周血嗜碱性白血病细胞(KU812)脱颗粒的影响,以阐明AFB_(1)暴露与食物过敏的相关性。方法 构建AFB_(1)暴露下OVA激发KU812细胞脱颗粒模型,采用酶联免疫吸附法(enzyme linked immunosorbent assay, ELISA)检测AFB_(1)对其生物活性介质β-氨基己糖苷酶(β-hexosaminidase,β-HEX)和组胺,以及细胞因子白细胞介素-4(interleukin-4, IL-4)、白细胞介素-6 (interleukin-6, IL-6)、白细胞介素-1β (interleukin-1β, IL-1β)释放量的影响;然后采用实时定量荧光聚合酶链反应法分析对IL-4和IL-6的mRNA表达水平的影响。结果 OVA刺激KU812细胞后会使其释放更多生物活性介质,包括β-HEX、组胺及细胞因子(IL-4、IL-6、IL-1β);当有AFB_(1)同时暴露,则会不同程度地加重这些生物活性介质的释放量。其中,AFB_(1)对β-HEX和组胺的释放量影响较小;但能够显著提高细胞因子IL-4、IL-6以及IL-1β的分泌量(P<0.01),尤其是对IL-1β的影响更显著,相较于对照组其分泌量提高84%。同时IL-4和IL-6的mRNA基因的表达水平也被提高。结论 OVA激发KU812会导致其脱颗粒并释放与食物过敏相关的一些活性介质和细胞因子。而AFB_(1)质量浓度为10000ng/mL的同时暴露,会提高这些相关活性介质和细胞因子的释放量,从而加重OVA所引发的食物过敏反应。

Objective To study the effects of aflatoxin B_(1)(AFB_(1))exposure on the degranulation of human peripheral blood basophilic leukemia cells(KU812)sensitized by ovalbumin(OVA),and clarify the correlation between AFB_(1) exposure and food allergy.Methods The degranulation model of KU812 cells being sensitized by OVA meanwhile exposed to AFB_(1) was firstly established.The effects of AFB_(1) on the release of some bioactive media and cytokines were detected by enzyme linked immunosorbent assay(ELISA),includingβ-hexosaminidase(β-HEX),histamine,interleukin-4(IL-4),interleukin-6(IL-6)and interleukin-1β(IL-1β),then real-time quantitative fluorescent polymerase chain reaction method was used to analyze the effects on the expression level of mRNA from IL-4 and IL-6,respectively.Results OVA could sensitize KU812 cells to releaseβ-HEX,histamine,and cytokines(IL-4,IL-6,IL-1β);in the meanwhile exposure to AFB_(1) these effects would be variously worsened.Among them,compared with the OVA group,the effect of AFB_(1) on release ofβ-HEX or histamine was relatively less,but the secretion of cytokines IL-4,IL-6 and IL-1βincreased significantly(P<0.01),in particular,the effect of IL-1βwas more significant,with an 84%increase in secretion compared to the control group.Meanwhile,mRNA expression levels of IL-4 and IL-6 were increased.Conclusion OVA sensitization can lead to degranulation of KU812 cells and release of some active mediators and cytokines associated with food allergy.When KU812 cells are sensitized by OVA meanwhile exposure to 10000 ng/mL AFB_(1),the release and secretion of some active media and cytokines,which associates with food allergy,can be got more increase during degranulation occurring,therefore,the OVA allergic reaction will be aggravated.