title: A panel of Trypanosoma brucei strains tagged with blue and red-shifted luciferases for bioluminescent imaging in murine infection models.
abstract: BACKGROUND
  Genetic engineering with luciferase reporter genes allows monitoring Trypanosoma brucei (T.b.) infections in mice by in vivo bioluminescence imaging (BLI). Until recently, luminescent T.b. models were based on Renilla luciferase (RLuc) activity. Our study aimed at evaluating red-shifted luciferases for in vivo BLI in a set of diverse T.b. strains of all three subspecies, including some recently isolated from human patients.
  
  
  RESULTS
  We transfected T.b. brucei, T.b. rhodesiense and T.b. gambiense strains with either RLuc, click beetle red (CBR) or Photinus pyralis RE9 (PpyRE9) luciferase and characterised their in vitro luciferase activity, growth profile and drug sensitivity, and their potential for in vivo BLI. Compared to RLuc, the red-shifted luciferases, CBR and PpyRE9, allow tracking of T.b. brucei AnTaR 1 trypanosomes with higher details on tissue distribution, and PpyRE9 allows detection of the parasites with a sensitivity of at least one order of magnitude higher than CBR luciferase. With CBR-tagged T.b. gambiense LiTaR1, T.b. rhodesiense RUMPHI and T.b. gambiense 348 BT in an acute, subacute and chronic infection model respectively, we observed differences in parasite tropism for murine tissues during in vivo BLI. Ex vivo BLI on the brain confirmed central nervous system infection by all luminescent strains of T.b. brucei AnTaR 1, T.b. rhodesiense RUMPHI and T.b. gambiense 348 BT.
  
  
  CONCLUSIONS
  We established a genetically and phenotypically diverse collection of bioluminescent T.b. brucei, T.b. gambiense and T.b. rhodesiense strains, including drug resistant strains. For in vivo BLI monitoring of murine infections, we recommend trypanosome strains transfected with red-shifted luciferase reporter genes, such as CBR and PpyRE9. Red-shifted luciferases can be detected with a higher sensitivity in vivo and at the same time they improve the spatial resolution of the parasites in the entire body due to the better kinetics of their substrate D-luciferin.
authors.affiliation: Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Nick
authors.initials: N
authors.lastname: Van Reet
authors.affiliation: Institute of Medical Microbiology, University Hospital of Münster, Münster, Germany.
authors.forename: Hélène
authors.initials: H
authors.lastname: Van de Vyver
authors.affiliation: Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium; Département de Parasitologie, Institut National de Recherche Biomédicale, Kinshasa Gombe, Democratic Republic of the Congo.
authors.forename: Patient Pati
authors.initials: PP
authors.lastname: Pyana
authors.affiliation: Faculty of Pharmaceutical, Biomedical and Veterinary Sciences, Bio-Imaging Lab, Department of Biomedical Sciences, University of Antwerp, Wilrijk, Belgium.
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Van der Linden
authors.affiliation: Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Philippe
authors.initials: P
authors.lastname: Büscher
mesh_terms: D000818:Animals; D001921:Brain / Q000469:parasitology; D004195:Disease Models, Animal; D005260:Female; D008156:Luciferases / Q000235:genetics; D008163:Luminescent Measurements; D051379:Mice; D014346:Trypanosoma brucei brucei / Q000302:isolation & purification*; D014353:Trypanosomiasis, African / Q000175:diagnosis*
chemical_list: D008156:Luciferases