Gene expression analysis of porcine whole blood cells infected with foot-and-mouth disease virus using high-throughput sequencing technology

: Foot-and-mouth disease virus (FMDV) is a single-stranded positive RNA virus that belongs to the family Picornaviridae. FMDV infects cloven-hoofed animals, such as pigs, sheep, goats, cattle and diverse wildlife species, and remains a major threat to the livestock industry worldwide. In this study, a transcriptome analysis of whole blood from pigs infected with FMDV was performed using the paired-end Illumina sequencing technique to understand the interactions between the pathogen and its host cells. During infection with FMDV, a total of 120 differentially expressed genes (DEGs) were identified, including 110 up-regulated genes and 10 down-regulated genes. To further investigate the DEGs involved in interactions between the virus and its host, gene ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were conducted. GO annotation indicated that a number of DEGs were enriched in categories involved in host-virus interactions, such as response to stimulus, immune system process and regulation of biological process. KEGG enrichment analysis indicated that the DEGs were primarily involved in the ribosome signaling pathway and immune-related signaling pathways. Ten DEGs, including the immune-related genes BTK1, C1QB, TIMD4 and CXCL10, were selected and validated using quantitative PCR, which showed that the expression patterns of these genes are consistent with the results of the in silico expression analysis. In conclusion, this study presents the first transcriptome analysis of pig whole blood cells infected with FMDV, and the results obtained in this study improve our understanding of the interactions between FMDV and host cells as well as the diagnosis and control of FMD.