title: Reverse vaccinology as an approach for developing Histophilus somni vaccine candidates.
abstract: Histophilosis of cattle is caused by the Gram negative bacterial pathogen Histophilus somni (H. somni) which is also associated with the bovine respiratory disease (BRD) complex. Existing vaccines for H. somni include either killed cells or bacteria-free outer membrane proteins from the organism which have proven to be moderately successful. In this study, reverse vaccinology was used to predict potential H. somni vaccine candidates from genome sequences. In turn, these may protect animals against new strains circulating in the field. Whole genome sequencing of six recent clinical H. somni isolates was performed using an Illumina MiSeq and compared to six genomes from the 1980's. De novo assembly of crude whole genomes was completed using Geneious 6.1.7. Protein coding regions was predicted using Glimmer3. Scores from multiple web-based programs were utilized to evaluate the antigenicity of these predicted proteins which were finally ranked based on their surface exposure scores. A single new strain was selected for future vaccine development based on conservation of the protein candidates among all 12 isolates. A positive signal with convalescent serum for these antigens in western blots indicates in vivo recognition. In order to test the protective capacity of these antigens bovine animal trials are ongoing.
authors.affiliation: Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan S7N 5E3, Canada. Electronic address: cam965@mail.usask.ca.
authors.forename: Claudia Avis
authors.initials: CA
authors.lastname: Madampage
authors.affiliation: Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan S7N 5E3, Canada.
authors.forename: Neil
authors.initials: N
authors.lastname: Rawlyk
authors.affiliation: Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan S7N 5E3, Canada.
authors.forename: Gordon
authors.initials: G
authors.lastname: Crockford
authors.affiliation: Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan S7N 5E3, Canada.
authors.forename: Yejun
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan S7N 5E3, Canada.
authors.forename: Aaron P
authors.initials: AP
authors.lastname: White
authors.affiliation: Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan S7N 5E3, Canada.
authors.forename: Robert
authors.initials: R
authors.lastname: Brownlie
authors.affiliation: Alberta Beef Health Solutions Inc, Box 307, Picture Butte, Alberta T0K 1V0, Canada.
authors.forename: Joyce
authors.initials: J
authors.lastname: Van Donkersgoed
authors.affiliation: Veterinary Agri-Health Services, 201-151 East Lake Blvd, Airdrie, Alberta T4A 2G1, Canada.
authors.forename: Craig
authors.initials: C
authors.lastname: Dorin
authors.affiliation: Vaccine and Infectious Disease Organization-International Vaccine Centre, University of Saskatchewan, 120 Veterinary Road, Saskatoon, Saskatchewan S7N 5E3, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Potter
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology; D001428:Bacterial Vaccines / Q000276:immunology*; D015153:Blotting, Western; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology / Q000517:prevention & control*; D019295:Computational Biology / Q000379:methods*; D003198:Computer Simulation; D004269:DNA, Bacterial / Q000235:genetics* / Q000302:isolation & purification; D015723:Gene Library; D016680:Genome, Bacterial; D006192:Haemophilus Infections / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary*; D044138:Haemophilus somnus / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification / Q000472:pathogenicity; D008957:Models, Genetic; D016366:Open Reading Frames / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000276:immunology / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D014774:Virulence
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D004269:DNA, Bacterial; D011993:Recombinant Fusion Proteins
keywords: Genome; Histophilus somni; Reverse-vaccinology