将 2周龄雏鸡随机分成 3组,试验组雏鸡颈部皮下注射 0.l mL 107个/mL 非复制型尿嘧啶营养缺陷型弓形虫(NRTUAs),感染对照组和空白对照组分别注射等剂量的RH虫株和PBS;于感染的第 4天采集各组雏鸡的心脏、肝脏、脾脏、肺脏、肾脏、睾丸、法氏囊、胸腺、脑、胸肌、腿肌组织,提取其DNA,采用绝对荧光定量PCR检测各器官组织的荷虫量;提取剩余脾脏组织的RNA,采用相对荧光定量PCR仪检测脾脏中IL-1β、IL-6、TNF-α、CCL26、STAT1、IRF1、IFN-γ、IL-10的转录水平.结果表明,雏鸡感染弓形虫的第 4天,各器官组织不能完全清除NRTUAs,除肝脏、睾丸、腿肌和脑组织外,NRTUAs组的组织荷虫量均显著低于RH组的;NRTUAs刺激脾脏不会使免疫相关细胞因子的转录水平显著上调或下调,说明NRTUAs是致病性较低的虫株,不会刺激雏鸡脾脏引发强烈的先天性免疫反应,不会引起促炎、抑炎因子的过量产生.
The effect of the parasite load and expression levels of splenic cytokines in chicks infected with nonreplicating Toxoplasma uracil auxotrophs
The 2-week-old chicks were randomly divided into 3 groups.The chicks of experimental group were injected subcutaneously with 0.1 mL inoculum suspension containing 107 nonreplicating Toxoplasma uracil auxotrophs(NRTUAs)per milliliter,and the chickens of the infected control group(RH group)and the blank control group were injected with equal doses of the virulent Toxoplasma gondii RH strains and PBS respectively.On the 4th day of infection,the heart,liver,spleen,lung,kidney,testis,bursa of Fabricius,thymus,brain,pectoral muscle and leg muscle of chicks in each group were collected,from which tissue DNA was extracted.The parasite load in each organ was detected by absolute fluorescence quantitative PCR.RNA was extracted from the remaining spleen of each group,and the transcription levels of IL-1 β,IL-6,TNF-α,CCL26,STAT1,IRF1,IFN-γ and IL-10 in spleens were detected by relative fluorescent quantitative PCR.The results showed that on the 4th day of Toxoplasma infection,NRTUAs were not completely cleared from all organs,and the parasite load of NRTUAs group was lower than that of RH group except for liver,testis,leg muscle and brain.Among them,the parasite load of heart in NRTUAs group accounted for 1.14%of that in the RH group,the parasite load of pectoralis in the NRTUAs group accounted for 0.63%of that in the RH group,the parasite load of spleen in the NRTUAs group accounted for 10.01%of that in the RH group,the parasite load of lung in the NRTUAs group accounted for 0.18%of that in the RH group,the parasite load of kidney in the NRTUAs group accounted for 2.86%of that in the RH group,the parasite load of thymus in the NRTUAs group accounted for 1.33%of that in the RH group,and the parasite load of bursa of Fabricius in NRTUAs group accounted for 0.75%of that in the RH group.The measured immune-related cytokines were not significantly up-regulated or down-regulated in the spleens with NRTUAs stimulation,the expression levels of which were similar to those in the PBS group.Therefore,NRTUAs was a low pathogenic strain,which did not stimulate strong innate immune response or excessive production of pro-inflammatory and anti-inflammatory factors in chicks spleens.
chicksnonreplicating Toxoplasma uracil auxotrophs(NRTUAs)parasite loadexpression levels of cytokines in spleenreal-time PCR
万方数据
维普
