title: OmpN, outer membrane proteins of Edwardsiella ictaluri are potential vaccine candidates for channel catfish (Ictalurus punctatus).
abstract: Outer membrane proteins (OMPs) are a class of proteins that reside in the outer membrane of Gram-negative bacteria. OMPs act as epitopes and are potential vaccine candidates. Outer membrane protein N (OmpN) is a component of the outer membrane of Edwardsiella ictaluri (E. ictaluri). In a previous study, the OmpN1-, OmpN2-, OmpN3-encoding genes of E. ictaluri were cloned, and here they were expressed in Escherichia coli. Western blotting showed that these three proteins had molecular weights of ∼60kDa. Channel catfish were immunized with recombinant OmpNs (rOmpNs) and then challenged with E. ictaluri. The results showed that rOmpN1, rOmpN2, and rOmpN3, as well as a mixture of all three proteins (in a ratio of 1:1:1) generated moderate immune protection (relative percentage of survival=62.5, 62.5, 67.5, and 75%, respectively). In an agglutination antibody titer assay, fish antisera showed an antibody titer of 1:128. Furthermore, each of the proteins stimulated high levels of lysozyme activity. In addition, a real-time polymerase chain reaction analysis revealed significant up-regulation of immune-related genes encoding major histocompatibility complex class I (MHC I), MHC II, CD4L, tumor necrosis factor-α, and interferon-γ after 24 and 48h of challenge, compared with the levels stimulated by phosphate-buffered saline. Taken together, we conclude that rOmpNs may elicit immune responses and generate protection against E. ictaluri in channel catfish. Thus, rOmpNs could be promising vaccine candidates against E. ictaluri.
authors: Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China.
authors: Qian
authors: Q
authors: Yang
authors: Animal Husbandry Bureau of Agriculture and Forestry of Sichuan Province, Cuiping district Goldfish Road No.20, Yibin 644000, Sichuan, PR China.
authors: Yan-Le
authors: YL
authors: Pan
authors: Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China. Electronic address: kywang1955@126.com.
authors: Kai-Yu
authors: KY
authors: Wang
authors: Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China.
authors: Jun
authors: J
authors: Wang
authors: Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China.
authors: Yang
authors: Y
authors: He
authors: Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China.
authors: Er-Long
authors: EL
authors: Wang
authors: Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China.
authors: Tao
authors: T
authors: Liu
authors: Department of Basic Veterinary, College of Veterinary Medicine, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China; Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China.
authors: Yi Geng
authors: Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China; Department of Aquaculture, College of Animal Science & Technology, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China.
authors: De-Fang
authors: DF
authors: Chen
authors: Key Laboratory of Animal Disease and Human Health of Sichuan Province, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China; Department of Aquaculture, College of Animal Science & Technology, Sichuan Agricultural University, Wenjiang district Huimin Road No.211, Chengdu 611130, Sichuan, PR China.
authors: Xiao-Li
authors: XL
authors: Huang
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology*; D001428:Bacterial Vaccines / Q000276:immunology*; D015153:Blotting, Western; D002397:Catfishes / Q000276:immunology / Q000382:microbiology*; D020610:Edwardsiella ictaluri / Q000276:immunology*; D004756:Enterobacteriaceae Infections / Q000662:veterinary*; D005393:Fish Diseases / Q000276:immunology* / Q000382:microbiology; D016133:Polymerase Chain Reaction
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines
keywords: Channel catfish; Edwardsiella ictaluri; Immune efficacy; Vaccine; rOmpNs