title: The virulence of Staphylococcus aureus correlates with strain genotype in a chicken embryo model but not a nematode model.
abstract: Staphylococcus aureus infections are of major importance in human and veterinary medicine. Studies of the virulence of this bacterium are complicated by inconsistent results obtained in different animal models. We searched for an uncomplicated and inexpensive model suitable to study virulence of poultry strains of S. aureus using a genome-wide approach. We determined that a useful model would clearly differentiate strains of high and low virulence, and that this would generally correlate with the genetic relatedness among strains. To this end Gallus gallus (chicken) embryo and Caenorhabditis elegans (nematode) models were selected, and their response to challenge by a set of well-characterized Staphylococcus strains was evaluated. The chicken embryo model allowed to determine variation in virulence among strains of poultry and human origin. The survival of embryos ranged from 0% to almost 100% for the various strains. In contrast, variation in virulence of most strains in the nematode model was comparable, regardless of their origin or genotype, demonstrating limited usefulness of this model. Most importantly, a clear correlation was found between the virulence level in the embryo model and the genotype of the tested poultry strains. Our findings indicate the potential usefulness of embryo model for future identification of host-specific adaptations and virulence factors in S. aureus.
authors.affiliation: Department of Microbiology, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland.
authors.forename: Klaudia
authors.initials: K
authors.lastname: Polakowska
authors.forename: Marcin W
authors.initials: MW
authors.lastname: Lis
authors.forename: Weronika M
authors.initials: WM
authors.lastname: Helbin
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Dubin
authors.forename: Adam
authors.initials: A
authors.lastname: Dubin
authors.forename: Jerzy W
authors.initials: JW
authors.lastname: Niedziolka
authors.forename: Jacek
authors.initials: J
authors.lastname: Miedzobrodzki
authors.forename: Benedykt
authors.initials: B
authors.lastname: Wladyka
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000382:microbiology*; D002642:Chick Embryo; D016000:Cluster Analysis; D004195:Disease Models, Animal; D005838:Genotype; D054884:Host-Pathogen Interactions; D058889:Molecular Typing; D011201:Poultry Diseases / Q000382:microbiology*; D013203:Staphylococcal Infections / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000235:genetics* / Q000472:pathogenicity*; D016019:Survival Analysis; D014774:Virulence