Evaluation of viral load and transcriptome changes in tracheal tissue of two hybrids of commercial broiler chickens infected with avian infectious bronchitis virus: a comparative study

Abstract

Infectious bronchitis virus (IBV) is one of the major threats to the poultry industry, with significant economic consequences. Despite strict measures, the disease is difficult to control worldwide. Experimental evidence demonstrates that the severity of IBV is affected by the genetic background of the chicken, and the selection of appropriate breeds can increase production efficiency. Therefore, the aim of the present study was to assess the strength of the immune response to IBV in tracheal tissues of Ross 308 and Cobb 500 broiler chickens by evaluating transcriptome changes, focusing on immune responses and the viral load in tracheal tissues two days after IBV infection. We identified 899 and 1350 differentially expressed genes (DEGs) in the Cobb 500 and Ross 308 experimental groups compared to their respective control groups. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated the involvement of signaling pathways (Toll-like receptor [TLR], NOD-like receptor [NLR], and RIG-I-like receptor [RLR] signaling pathways). Interestingly, the RLR signaling pathway appears to be affected only in the Cobb hybrid. Furthermore, the viral loads in tracheal samples obtained from the Ross challenged group were significantly higher than those of the Cobb challenged group. The results of this study indicated that the host transcriptional response to IBV infection as well as the viral load can differ by hybrid. Furthermore, genes such as TLR-3 , ChIFN-α , MDA5 , LGP2 , IRF-7 , NF-κB , and TRIM25 may interfere with IBV proliferation. Supplementary Information The online version contains supplementary material available at 10.1007/s00705-021-05322-5.

Host Immune Response Modulation in Avian Coronavirus Infection: Tracheal Transcriptome Profiling In Vitro and In Vivo

“…Smith and colleagues identified several important DE genes in IBV Mass41-infected tracheal tissues from susceptible and resistant birds, such as TLR3, IRF7, STAT1, IFIH1 (MDA5), MX1, IFIT5, and OASL, which were also up-regulated in our IBV-infected tracheal tissue data [ 43 ]. Ghobadian and colleagues indicated that the Iranian variant-2-like IBV strain IS/1494 induced variable host gene expression in different chicken hybrid tracheal tissues but also demonstrated the importance of certain genes such as TLR3, IFIH1 (MDA5), and IRF7 and the enrichment of the TLR signaling pathways [ 45 ]. Many of the important genes mentioned in the studies above and found in our DE gene data emphasize the importance of ISGs.…”

“…Since the early 2000s, researchers have aimed to map the host gene expression patterns involved in IBV infection [ 37 , 38 , 39 ]. More recent transcriptomic studies have looked at chicken spleen tissues [ 40 , 41 , 42 ], tracheal tissues [ 43 , 44 , 45 ], lung tissues [ 41 ], human lung epithelial-like cells [ 46 ], chicken kidney tissues and cells [ 47 , 48 , 49 , 50 , 51 ], dendritic cells [ 52 , 53 ], macrophages [ 54 ], and fibroblasts [ 55 ] upon infection with various strains of IBV. Currently, there are no RNA-seq studies specifically looking at IBV infection in chicken tracheal epithelial cells (cTECs), nor using the IBV DMV/1639 strain, which has been the dominant IBV genotype circulating in Canada [ 21 , 22 ] and the United States of America (USA) in recent years [ 20 , 56 ].…”

Comparison of Field and Hatchery Practices in Spray Vaccination Against Infectious Bronchitis

“…Aşı uygulama kalitesi broylerlerde hastalıklar ile mücadelede en önemli etkenlerdir. Çiftliklerde biyogüvenlik tedbirlerinin optimum düzeyde tutulması bulaşma kaynaklarının azalmasına neden olmaktadır [46]. IB hastalığında bölgenin risk altında olduğu durumlarda aşılamanın önemi artar.…”