聚肌胞苷酸刺激对鳜免疫因子活性及干扰素基因表达的影响

【目的】比较聚肌胞苷酸（Poly I:C）刺激对鳜（Siniperca chuatsi）免疫因子活性及干扰素系统相关基因表达的影响，为判断和指导鳜养殖过程中病原刺激后免疫应答和病毒监测提供参考依据。【方法】采用Poly I:C模拟病毒刺激，比较注射后不同时序（0、3、6、12、24、36、48和72 h）鳜白细胞组成百分比，以双抗体夹心酶联免疫法检测补体蛋白水平变化，荧光PCR相对定量检测免疫相关基因表达变化。【结果】血液白细胞百分比中，血栓细胞>单核细胞>淋巴细胞>嗜中性粒细胞，其中，与对照组比较，处理组6~72 h单核细胞百分比极显著提高（P<0.01，下同），且于48 h达峰值后恢复至初始水平，嗜中性粒细胞占比均有明显提升，淋巴细胞、血栓细胞占比均呈下降趋势。处理组血清补体C3含量在3 h高于初始，6 h低于初始，与对照组差异显著（P<0.05，下同）；补体C4含量处理组3 h显著高于对照组，6、24、48 h显著低于对照组。与初始0 h相比，处理组肾脏、胸腺、脾脏和肝脏IRF7基因表达量分别从3和6 h开始极显著上调，且胸腺表达量最高；处理组肾脏和肝脏IFNh基因表达量3~12 h极显著上调，胸腺IFNh基因表达量于6 h达峰值，12 h后恢复下降，脾脏IFNh基因表达在各时段均低于初始；处理组肾脏、胸腺、肝脏、脾脏IFNc基因表达量于12 h极显著上调，然后逐渐下降，分别于72、72、48和72 h达最低水平。【结论】鳜受Poly I:C模拟病毒刺激后，血细胞中各类白细胞、血清酶补体C3和C4含量有不同变化，干扰素在不同时序显著影响各组织中的表达变化。

Effects of polyinosinic acid stimulation on immune factor activity and interferon gene expression in Siniperca chuatsi

【Objective】 To compare the effects of polyinosinic acid(Poly I:C) stimulation on immune factor activity and gene expression related to interferon system in Siniperca chuatsi, and to provide a reference basis for estimating and guiding immune response and virus monitoring after pathogen stimulation in S. chuatsi culture.【Method】 Using Poly I:C to mimic viral stimulation, the percentage of leukocyte composition of S. chuatsi at different time sequences(0, 3, 6, 12, 24, 36, 48 and 72 h) after injection was compared and double antibody sandwich enzyme-linked immunosorbent assay (ELISA) was used to detect changes of complement protein and relative expression of immune related genes by real-time fluorescence quantitative PCR.【Result】 In the percentage of blood leukocytes, thrombu > monocyte > lymphocyte > neutrophil, among which, in the treatment group, the percentage of monocytes in the treatment group increased extremely significantly from 6 to 72 h(P<0.01, the same below) and returned to the initial level after peaking at 48 h. The percentage of neutrophils increased significantly, and the percentages of lymphocytes and thrombus cells decreased. Serum complement C3 in the treatment group were higher than that in initial level after 3 h, lower than initial level at 6 h, significantly different from that in control(P<0.05, the same below). Complement C4 levels in the treatment group were significantly higher than the control group at 3 h and significantly lower than the control group at 6, 24 and 48 h. Compared with initial 0 h, the expression of IRF7 gene in kidney, liver, spleen and thymus in the treatment group was extremely significantly upregulated from 3 h and from 6 h, and the expression in thymus was the highest; the expression of IFNh gene in kidney and liver in the treatment group was extremely significantly up-regulated at 3 h, peaked in thymus appeared at 6 h, and decreased again at 12 h, IFNc gene in spleen at all times were loner than initial time; the expression of IFNc gene in kidney, thymus, liver and spleen in the treatment group was extremely significant up-regulated at 12 h and then gradually decreased and reached the minimum at 72, 72, 48 and 72 h.【Conclusion】 S. chuatsi after virus stimulation mimicked by Poly I:C, various types of leukocytes in blood cells, serum enzyme complement C3 and C4 change differently, and interferon significantly affects expression changes in various tissues at different time sequences.