聚肌胞(Poly I:C)是一种天然双链RNA(Double strand RNA, dsRNA)的拟似物,能够模拟病毒感染后所形成的 dsRNA 及刺激机体产生抗病毒免疫反应。文章以抗病力存在差异的大蒲莲和长白仔猪为研究对象,分离外周血单核细胞(Peripheral blood mononuclear cell, PBMC),在20μg/mL的Poly I:C的免疫刺激下体外培养24 h,对影响免疫应答过程中的7个细胞因子(IRF3、IL6、IL8、IL10、TNFα、IFNγ和IFNα)和3个模式识别受体(TLR3、TLR4和RIG1)利用实时荧光定量PCR检测Poly I:C免疫刺激组相对于对照组的基因表达变化倍数。结果表明:检测的大部分细胞因子和受体(6个)表达量变化倍数很大,其中3种白细胞介素IL6、IL8和IL10免疫刺激变化倍数最大,平均变化倍数分别为20.71、10.87和5.18倍。对不同个体和品种间的比较发现,不仅大蒲莲和长白两品种间(大蒲莲猪的变化倍数平均高于长白猪)而且同品种的3头全同胞仔猪间对Poly I:C免疫刺激的应答也存在较大的变化。文章利用Poly I:C体外模拟dsRNA对PBMC的感染,为下一步筛选仔猪对Poly I:C刺激的免疫应答基因及鉴定大蒲莲猪特殊的抗性基因奠定了基础。
Polyinosinic-polycytidylic acid (Poly I:C) is an analogue of natural double strand RNA (dsRNA), which can simulate the viral dsRNA and stimulate the immune response. In the present study, peripheral blood mononuclear cells (PBMC) were isolated from piglets of Dapulian and Landrace with different disease resistance, and stimulated with 20μg/mL Poly I:C for 24 hours in vitro culture. The expression of several cytokines (IL6, IL8, TNFα, IL10, IRF3, IFNαand IFNγ) and three pat-tern recognition receptors (TLR3, TLR4 and RIG1) was determined by qRT-PCR. The results showed that, most of the cyto-kines or receptors had obvious expression change compared with the control (without Poly I:C stimulation), especially the three cytokine genes IL6, IL8 and IL10, whose average expression change times were 20.71, 10.87 and 5.18, respectively. Ex-pression comparison between breeds and among individuals of the same breed indicated that there was obvious difference not only between Dapulain and Landrace (Dapulain higher than Landrace) but also among the three individuals of the same breed. Our study simulated the infection of dsRNA to host cells using Poly I:C, and provided experimental foundation for further study on selecting the immune genes in response to Poly I:C stimulation and identifying the unique disease-resistance genes of Dapulian.