重组猪干扰素α对急性病毒性腹泻仔猪肾脏损伤的保护作用研究

Research of recombinant porcine interferon α on renal injury in reducing viral diarrhea in piglets

关键词:  重组猪干扰素α  PEDV  腹泻模型  肾脏损伤

Key words:  recombinant porcine interferon α  PEDV  diarrhea model  kidney damage

摘要:

(目的)研究重组猪干扰素α(recombinant porcine interferon α,rPoIFNα)在人工感染仔猪病毒性腹泻模型上对肾脏损伤的保护作用。(方法)选取7日龄健康三元哺乳仔猪15头,单圈隔离适应性饲喂人工乳3 d后,按体重相近原则,随机分为rPoIFNα治疗组和 猪流行性腹泻病毒(porcine epidemic diarrhea virus,PEDV)感染对照组 ,并设置正常对照组 。PEDV感染对照组 和rPoIFNα治疗组仔猪经口饲喂4mL病毒悬液(接种量为4.0×10_^5.5TCID50/头),正常对照组仔猪则同时同种方式饲喂4 mL生理盐水。攻毒8h后rPoIFNα治疗组仔猪给予注射rPoIFNα 100万单位/头/天,连续注射3天；PEDV感染对照组和正常对照组注射等量2 mL生理盐水。密切观察感染后72 h期间仔猪临床表现、肾组织剖检和HE染色结果,并采集三组仔猪血液和尿液样本进行肾功能指标(肌酐、尿素氮和尿酸)检测。(结果)攻毒后72h,PEDV感染对照组全部出现腹泻、脱水等典型病毒性腹泻症状,仔猪小肠及肾脏病料组织的PEDV核酸检测为阳性。rPoIFNα治疗组可有效治疗PEDV引起的仔猪腹泻,发病率降低至60%,并且发病仔猪全部治疗有效,有效率为100%,PEDV核酸检测阳性率仅为30%；与正常对照组相比,PEDV感染对照组仔猪血肌酐存在显著差异,rPoIFNα治疗组无明显差异；PEDV感染对照组 仔猪尿比重较其他两组偏高,存在颗粒管型和蛋白尿症状,并且肾间质中出现嗜酸性粒细胞,提示超敏反应导致的肾脏损伤。(结论)结果证明,rPoIFNα能够对哺乳仔猪病毒性腹泻导致的肾脏损伤具有明显保护作用。

Abstract:

(Objective) Research the protective effect of recombinant porcine interferon α (rPoIFN α) on renal injury in the model of artificial infectious diarrhea. (Method) 15 healthy three-way Suckling piglets of 7 days old were randomLy divided into rPoIFNα treatment group and PEDV control group according to the principle of similar body weight after feeding artificial milk for 3 days in isolation,and set negative control group. Piglets of PEDV control group and interferon treatment group were fed with 4mL virus suspension via mouth (inoculation amount 4.0×10^5.5TCID50/ head), while piglets of negative control group were fed with 4mL normal saline in the same way. Eight hours after the challenge, the piglets in the rPoIFNα treatment group were injected with rPoIFNα 1.0×10⁶U/Head/d, continuous injection for 3 days ;and the control group with PEDV infection was injected with the same amount 2 mL normal saline. The clinical manifestations, renal tissue necropsies and HE staining results of piglets during the 72-h post-infection period were closely observed, and blood and urine samples from three groups of piglets were collected for renal function indexes (creatinine, urea nitrogen and uric acid) detection. (Result)72h after challenge, typical viral diarrhea symptoms such as diarrhea and dehydration occurred in the PEDV control group,and the detection of PEDV nucleic acid in the diseased tissues of small intestine and kidney of piglets was positive.The rPoIFNα treatment group could effectively treat piglet diarrhea caused by PEDV,the incidence rate was reduced to 60%, and all the piglets were effective, with an effective rate of 100%,and the positive rate of nucleic acid detection of PEDV was only 30%. Compared with the negative control group,there was a significant difference with the PEDV control group,and there was no significant difference in the serum creatinine of the piglets treated with rPoIFNα.The urine proportion of piglets in the PEDV control group was higher than that in the other two groups, with symptoms of pellet tubulotype and proteinuria, and the presence of eosinophils in the renal stroma, suggesting renal injury caused by allergic reactions. (Conclusion) Recombinant porcine interferon α can reduce the kidney damage caused by viral diarrhea in suckling piglets.