Preventive effect and mechanism of chIFN-γ-chCD154 against Salmonella typhi-murium infection in White Leghorn chickens
10.16303/j.cnki.1005-4545.2025.04.12
- VernacularTitle:ChIFN-γ-chCD154预防白来航鸡鼠伤寒沙门菌感染的作用及其机制
- Author:
Jingya ZHANG
1
;
Guofan REN
;
Honglin XIE
;
Juan WANG
;
Zengqi YANG
;
Yefei ZHOU
;
Xinglong WANG
Author Information
1. 西北农林科技大学动物医学院,陕西杨凌 712100
- Publication Type:Journal Article
- Keywords:
Salmonella typhimurium;
chIFN-γ-chCD154;
White Leghorn chickens;
survival rate
- From:
Chinese Journal of Veterinary Science
2025;45(4):707-716,737
- CountryChina
- Language:Chinese
-
Abstract:
This study aims to evaluate the preventive effect of the exogenous protein chIFN-γ-chCD154 against Salmonella typhimurium(S.typhimurium)infection in White Leghorn chick-ens,and the potential mechanism.In this study,Escherichia coli was used to express the proteins chIFN-γ,chCD154 and chIFN-γ-chCD154.Before S.typhimurium infection,the White Leghorn chickens were pre-immunized via drinking water for three consecutive days,and infected with S.typhimurium by gavage.The results from Western blot,quantitative real-time PCR(qRT-PCR)analysis and histopathology analysis showed that compared to chIFN-γ and chCD154,chIFN-γ-chCD154 pre-treatment could synergistically increase the survival rate of infected chickens,reduce the bacterial load in the liver and cecum,and attenuate the pathological damage of liver and cecum.Moreover,chIFN-γ-chCD154 significantly decreased the mRNA expression of Toll-like receptor-4(TLR-4)and myeloid differentiation primary response gene 88(MyD88)in the cecum,and then inhibited the mRNA expression of NF-κB and pro-inflammatory cytokines(TNF-α and IL-6),and maintained the integrity of the intestinal tight junction proteins(zo-1,claudin-1,occlu-din).Compared with single protein pretreatment,chIFN-γ-chCD154 pretreatment significantly up-regulated the mRNA expression of the genes related to the vitamin D(VD)pathway(cyp27b1,VD receptor VDR,antimicrobial peptide AvBD7 and cathelicidin-b1)in S.typhimurium-infected peripheral blood mononuclear cells(PBMCs).The results of colony counting showed that the num-ber of S.typhimurium in the chIFN-γ-chCD154 group were the lowest.Also,chIFN-γ-chCD154 could up-regulate the relative abundance of beneficial bacteria such as Blautia,Ruminococcus,En-terococcus and Faecalibacterium,while down-regulate the relative abundance of harmful bacteria such as Staphylococcaceae in the cecum and improve the intestinal dysbiosis.In conclusion,chIFN-γ-chCD154 could activate the VD-antimicrobial peptide pathway and inhibit the TLR-4/MyD88/NF-κB inflammatory signaling pathway in S.typhimurium-infected chickens,which significantly improve the intestinal barrier function,reduce the inflammatory damage of liver and cecum,im-prove the structure of cecum microbial,promote the health of intestinal tract,and provide theoreti-cal basis for the development of chIFN-γ-chCD154 as a safe and effective alternative antibiotic.
