title: Protective efficacy of four recombinant fimbrial proteins of virulent Aeromonas hydrophila strain ML09-119 in channel catfish.
abstract: Aeromonas hydrophila is a reemerging pathogen of channel catfish (Ictalurus punctatus); recent outbreaks from 2009 to 2014 have caused the loss of more than 12 million pounds of market size catfish in Alabama and Mississippi. Genome sequencing revealed a clonal group of A. hydrophila isolates with unique genetic and phenotypic features that is highly pathogenic in channel catfish. Comparison of the genome sequence of a representative catfish isolate (ML09-119) from this virulent clonal group with lower virulence A. hydrophila isolates revealed four fimbrial proteins unique to strain ML09-119. In this work, we expressed and purified four A. hydrophila fimbrial proteins (FimA, Fim, MrfG, and FimOM) and assessed their ability to protect and stimulate protective immunity in channel catfish fingerlings against A. hydrophila ML09-119 infection for vaccine development. Our results showed catfish immunized with FimA, Fim, FimMrfG, and FimOM exhibited 59.83%, 95.41%, 85.72%, and 75.01% relative percent survival, respectively, after challenge with A. hydrophila strain ML09-119. Bacterial concentrations in liver, spleen, and anterior kidney were significantly (p<0.05) lower in vaccinated fish compared to the non-vaccinated sham groups at 48h post-infection. However, only the Fim immunized group showed a significantly higher antibody titer in comparison to the non-vaccinated treatment group (p<0.05) at 21days post-vaccination. Altogether, Fim and FimMrfG recombinant proteins have potential for vaccine development against virulent A. hydrophila infection.
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Hossam
authors.initials: H
authors.lastname: Abdelhamed
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Seong Won
authors.initials: SW
authors.lastname: Nho
authors.affiliation: Center for Excellence in Regenerative Health and Biotechnology, University of Florida, Gainesville, FL 32611, USA.
authors.forename: Gokul
authors.initials: G
authors.lastname: Turaga
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Banes
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA. Electronic address: a.karsi@msstate.edu.
authors.forename: Attila
authors.initials: A
authors.lastname: Karsi
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA. Electronic address: lawrence@cvm.msstate.edu.
authors.forename: Mark L
authors.initials: ML
authors.lastname: Lawrence
mesh_terms: D016980:Aeromonas hydrophila / Q000472:pathogenicity*; D000818:Animals; D001426:Bacterial Proteins / Q000276:immunology*; D001428:Bacterial Vaccines / Q000276:immunology*; D010861:Fimbriae, Bacterial / Q000378:metabolism*; D005393:Fish Diseases / Q000382:microbiology / Q000517:prevention & control*; D016905:Gram-Negative Bacterial Infections / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary; D007059:Ictaluridae; D011994:Recombinant Proteins; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D011994:Recombinant Proteins
keywords: Aeromonas hydrophila; Channel catfish; Fimbrial proteins