title: Galleria mellonella is an effective model to study Actinobacillus pleuropneumoniae infection.
abstract: Actinobacillus pleuropneumoniae is responsible for swine pleuropneumonia, a respiratory disease that causes significant global economic loss. Its virulence depends on many factors, such as capsular polysaccharides, RTX toxins and iron-acquisition systems. Analysis of virulence may require easy-to-use models that approximate mammalian infection and avoid ethical issues. Here, we investigate the potential use of the wax moth Galleria mellonella as an informative model for A. pleuropneumoniae infection. Genotypically distinct A. pleuropneumoniae clinical isolates were able to kill larvae at 37 °C but had different LD50 values, ranging from 10(4) to 10(7) c.f.u. per larva. The most virulent isolate (1022) was able to persist and replicate within the insect, while the least virulent (780) was rapidly cleared. We observed a decrease in haemocyte concentration, aggregation and DNA damage post-infection with isolate 1022. Melanization points around bacterial cells were observed in the fat body and pericardial tissues of infected G. mellonella, indicating vigorous cell and humoral immune responses close to the larval dorsal vessel. As found in pigs, an A. pleuropneumoniae hfq mutant was significantly attenuated for infection in the G. mellonella model. Additionally, the model could be used to assess the effectiveness of several antimicrobial agents against A. pleuropneumoniae in vivo. G. mellonella is a suitable inexpensive alternative infection model that can be used to study the virulence of A. pleuropneumoniae, as well as assess the effectiveness of antimicrobial agents against this pathogen.
authors.affiliation: Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil.
authors.forename: Monalessa Fábia
authors.initials: MF
authors.lastname: Pereira
authors.affiliation: Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil.
authors.forename: Ciro César
authors.initials: CC
authors.lastname: Rossi
authors.affiliation: Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil.
authors.forename: Marisa
authors.initials: M
authors.lastname: Vieira de Queiroz
authors.affiliation: Laboratório de Biologia Molecular de Insetos, Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Brazil.
authors.forename: Gustavo Ferreira
authors.initials: GF
authors.lastname: Martins
authors.affiliation: Department of Zoology, Ambrose Alli University, Akpoma, Nigeria.|Laboratório de Biologia Molecular de Insetos, Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Brazil.
authors.forename: Clement
authors.initials: C
authors.lastname: Isaac
authors.affiliation: Section of Paediatrics, Imperial College London, London, UK.
authors.forename: Janine T
authors.initials: JT
authors.lastname: Bossé
authors.affiliation: Section of Paediatrics, Imperial College London, London, UK.
authors.forename: Yanwen
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
authors.forename: Brendan W
authors.initials: BW
authors.lastname: Wren
authors.affiliation: Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
authors.forename: Vanessa Sofia
authors.initials: VS
authors.lastname: Terra
authors.affiliation: Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
authors.forename: Jon
authors.initials: J
authors.lastname: Cuccui
authors.affiliation: Section of Paediatrics, Imperial College London, London, UK.
authors.forename: Paul R
authors.initials: PR
authors.lastname: Langford
authors.affiliation: Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil.
authors.forename: Denise Mara Soares
authors.initials: DMS
authors.lastname: Bazzolli
mesh_terms: D000189:Actinobacillus Infections / Q000382:microbiology*; D016977:Actinobacillus pleuropneumoniae / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D000818:Animals; D004195:Disease Models, Animal; D006801:Humans; D007814:Larva / Q000382:microbiology; D009036:Moths / Q000382:microbiology*; D014774:Virulence