鼠伤寒沙门氏菌感染诱导鸡盲肠及脾脏TLR基因差异表达

Differential expression of chicken TLR genes between spleen and cecum following the Salmonella typhimuriuminfection

为研究鼠伤寒沙门氏菌感染后不同时间鸡盲肠和脾脏组织TLR4、TLR5、TLR15和TLR21 mRNA的表达规律,选用沙门氏菌阴性济宁百日鸡36只,随机分为2组,饲喂于隔离器中,2日龄分别接种1.23×108cfu鼠伤寒沙门氏菌和PBS溶液,接种后第1、3和7天采集盲肠和脾脏组织样品,应用荧光定量PCR检测感染后各时间、各组织中TLR4、TLR5、TLR15和TLR21的表达量。结果显示,1)济宁百日鸡感染鼠伤寒沙门氏菌后盲肠中TLR4、TLR5、TLR15和TLR21表达量均发生显著变化(P<0.05);2)脾脏中TLR21和TLR4的表达量分别在接种后第1天和第3天显著上调(P<0.05),而TLR5和TLR15的表达量差异不显著;3)感染后各时间点脾脏中TLR5的表达量显著低于盲肠(P<0.01),而TLR4、TLR15和TLR21表达量均显著高于盲肠(P<0.05)。鼠伤寒沙门氏菌感染后,鸡TLRs在盲肠和脾脏中发挥着不同的调控作用,而且这种表达调控表现出一定的时序性。

This experiment was conducted to study the differential expression levels of TLR4,TLR5,TLR15 and TLR21 in spleen and cecum in Jining Bairi chicken after the Salmonella typhimurium(S.typhimurium)infection.Thirty-six S.typhimuriu-negative Jining Bairi chickens were randomly divided into 2groups(a treated group and a control group with18 chickens in each group)and raised in different isolators.Each chicken in the treated group was orally inoculated with0.3mL of inoculum containing approximately 1.23×108 cfu S.typhimurium.Chickens in the control group were mockinoculated with PBS.Cecum and spleen were collected at day 1,3and 7post inoculation(dpi).Quantitative real-time PCR was performed to detect the expression levels of TLR4,TLR5,TLR15 and TLR21 in spleen and cecum.After the inoculation,the expression levels of TLR4,TLR5,TLR15 and TLR21 in cecum were significantly different(P<0.05)at each time point.The expression levels of TLR21 and TLR4 in spleen were significantly up-regulated(P<0.05)at 1and 3dpi,respectively.The expression levels of TLR5 and TLR15 in spleen were not significantly different.Between the two detected tissues,the expression levels of TLR5 in spleen were significantly lower than that in cecum following the S.typhimuriuminoculation(P<0.01).However,the expression levels of TLR4,TLR15 and TLR21 in spleen weresignificantly higher than that in cecum following the S.typhimurium inoculation(P <0.05).The result herein demonstrated that chicken TLRs played different regulatory roles in spleen and cecum in the response to the S.typhimuriuminfection in Jining Bairi chicken,the expression levels of TLRs showed a temporal variation following the S.typhimuriuminfection.