title: Autophagy Is Associated with Pathogenesis ofHaemophilus parasuis.
abstract: Haemophilus parasuis(H. parasuis) is a common commensal Gram-negative extracellular bacterium in the upper respiratory tract of swine, which can cause Glässer's disease in stress conditions. Research on the pathogenicity ofH. parasuishas mainly focused on immune evasion and bacterial virulence factors, while few studies have examined the interactions ofH. parasuisand its host. Autophagy is associated with the replication and proliferation of many pathogenic bacteria, but whether it plays a role during infection byH. parasuisis unknown. In this study, an adenovirus construct expressing GFP, RFP, and LC3 was used to infectH. parasuis. Western blotting, laser confocal microscopy, and electron microscopy showed that Hps5 infection induced obvious autophagy in PK-15 cells. In cells infected with strains ofH. parasuisdiffering in invasiveness, the levels of autophagy were positively correlated with the presence of alive bacteria in PK-15 cells. In addition, autophagy inhibited the invasion of Hps5 in PK-15 cells. Autophagy related genes Beclin, Atg5 and Atg7 were silenced with RNA interference, the results showed that autophagy induced byH. parasuisinfection is a classical pathway. Our observations demonstrate thatH. parasuiscan induce autophagy and that the levels of autophagy are associated with the presence of alive bacteria in cells, which opened novel avenues to further our understanding ofH. parasuis-host interplay and pathogenesis.
authors.affiliation: Key Laboratory of Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University Nanjing, China.
authors.forename: Yaning
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University Nanjing, China.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University Nanjing, China.
authors.forename: Wentao
authors.initials: W
authors.lastname: Yuan
authors.affiliation: Key Laboratory of Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University Nanjing, China.
authors.forename: Yuting
authors.initials: Y
authors.lastname: Xia
authors.affiliation: Key Laboratory of Bacteriology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University Nanjing, China.
authors.forename: Yijuan
authors.initials: Y
authors.lastname: Shen
keywords: Haemophilus parasuis; adenovirus; autophagy; invasion; pathogenesis