title: Passive immunisation against Pseudomonas aeruginosa recombinant flagellin in an experimental model of burn wound sepsis.
abstract: BACKGROUND
  This study was aimed to investigate whether anti-recombinant flagellin type A (anti r-fla-A) immunoglobulin G (IgG) provides protection in a mouse burn model of infection, and to determine the role of anti r-fla-A IgG as an opsonin and motility inhibitor in local and systemic infections.
  
  
  METHODS
  Following the preparation of r-flagellin type A, rabbit polyclonal IgG was prepared. Specificity of anti r-flagellin for r-flagellin was evaluated by immunoblot analysis. After burn and challenge, mortality rate was screened in the mice treated with anti r-fla-A IgG. The ability of antiserum to promote phagocytosis of bacteria was assessed by the opsonophagocytosis testing. Functional activity of anti r-fla-A IgG was assessed in vitro by motility inhibition assay. Bacterial quantity in skin and internal organs was evaluated to study systemic infection.
  
  
  RESULTS
  In vivo administration of anti r-fla-A IgG resulted in a significant improvement in survival in mice infected by a homologous strain of Pseudomonas aeruginosa from 16.6% to 75% compared with the control IgG. By contrast, this rate was 33.3% in the mice infected by the heterologous strain, PAO1 (type B flagellated strain). Protection was improved by giving a second treatment of r-flagellin antisera at 24-h post-burn and infection. Furthermore, anti r-fla-A IgG enhanced considerably the phagocytosis of the homologous strain but it was slight in the heterologous strain. The antiserum against r-flagellin type A was able to inhibit the motility of the PAK strain (type A flagellated strain), but slight inhibition was observed against PAO1. Meanwhile, anti r-fla-A IgG inhibited the systemic spread of PAK strain from the site of infection to internal organs.
  
  
  CONCLUSIONS
  In this study, passive immunisation with anti r-fla-A IgG was active against a homologous strain of infecting P. aeruginosa, but lost most of its efficiency against a heterologous strain. Therefore, passive treatment with anti r-fla-A IgG might protect burned mice against local and systemic infection of P. aeruginosa.
authors.affiliation: Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Sobhan
authors.initials: S
authors.lastname: Faezi
authors.forename: Morteza
authors.initials: M
authors.lastname: Sattari
authors.forename: Mehdi
authors.initials: M
authors.lastname: Mahdavi
authors.forename: Mehryar Habibi
authors.initials: MH
authors.lastname: Roudkenar
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D015153:Blotting, Western; D002056:Burns / Q000188:drug therapy / Q000382:microbiology*; D005408:Flagellin / Q000276:immunology*; D007116:Immunization, Passive; D007074:Immunoglobulin G / Q000276:immunology; D051379:Mice; D010587:Phagocytosis / Q000187:drug effects; D011552:Pseudomonas Infections / Q000276:immunology / Q000401:mortality / Q000517:prevention & control*; D011550:Pseudomonas aeruginosa / Q000276:immunology; D011994:Recombinant Proteins / Q000627:therapeutic use; D018805:Sepsis / Q000188:drug therapy / Q000382:microbiology* / Q000517:prevention & control; D012867:Skin / Q000382:microbiology; D014946:Wound Infection / Q000188:drug therapy / Q000382:microbiology
chemical_list: D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D011994:Recombinant Proteins; D005408:Flagellin