鸡肠相关性淋巴组织中IFN-γ和IL-2 mRNA表达的动态变化

Dynamic changes of IFN-γmRNA and IL-2 mRNA expressions in chicken gut-associated lymphoid tissue

通过实时荧光定量PCR方法,检测鸡在胚胎时期和出壳后初期肠道相关性淋巴组织(GALT)中IFN-γ基因和IL-2基因mRNA的表达水平,从而了解鸡GALT免疫功能的建立情况并反映鸡在此阶段的免疫状态。结果显示,胚胎20日龄和出壳后1日龄各肠段GALT中均有少量IL-2mRNA和IFN-γmRNA的表达。盲肠扁桃体、直肠和食管扁桃体中IL-2基因的表达水平在出壳后4日龄时显著升高(P<0.05),而在7日龄时又略有下降。除食管扁桃体外,各肠段GALT中IFN-γmRNA的表达水平在4日龄时显著升高(P<0.05),而空肠、回肠和直肠中其表达水平在7日龄时又显著下降(P<0.05)。各肠段在第2周内IL-2基因和IFN-γ基因表达水平迅速升高,并在14日龄时达到最高峰,之后各日龄都趋于稳定。另外,各日龄同一肠段IFN-γ基因的表达水平要明显高于IL-2基因的表达水平。证实,鸡GALT在出壳后4日龄就初步具有细胞免疫功能,直至第2周尤其是14日龄时其功能基本达到成熟水平。

The mRNA expression levels of IFN-γ and IL-2 gene in chicken gut-associated lymphoid tissue（GALT） were detected by real-time PCR.Accordingly,the establishment of immune function in chicken GALT could be understood,and the immune state at this stage could be reflected.The findings showed that there were some expression of IFN-γ and IL-2 gene in each intestine section on embryonic day 20 and the first day post-hatch.The expression of IL-2 in cecal tonsil,rectum and esophago tonsil significantly increased on day 4 post-hatch（P0.05）,but slightly decreased on day 7 post-hatch.The expression of IFN-γ in each intestine section except esophago tonsil significantly increased on day 4 post-hatch（P0.05）,but significantly decreased on day 7 post-hatch in jejunum,ileum and rectum（P0.05）.The expression level of IFN-γ and IL-2 gene mRNA increased quickly in each intestine section during the second week,and reached peak on day 14 post-hatch,afterward to be stable.Moreover,the average expression level of IFN-γ in the same intestine section at every stage was significantly higher than that of IL-2.These results revealed that there were celluar immune function initially in chicken GALT from day 4 post-hatch,and reached the mature level until the second week post-hatch especially when chickens were 14 days-old.