title: Luciferase-expressing Leishmania infantum allows the monitoring of amastigote population size, in vivo, ex vivo and in vitro.
abstract: Here we engineered transgenic Leishmania infantum that express luciferase, the objectives being to more easily monitor in real time their establishment either in BALB/c mice--the liver and spleen being mainly studied-or in vitro. Whatever stationary phase L. infantum promastigotes population--wild type or engineered to express luciferase-the parasite burden was similar in the liver and the spleen at day 30 post the intravenous inoculation of BALB/c mice. Imaging of L. infantum hosting BALB/C mice provided sensitivity in the range of 20,000 to 40,000 amastigotes/mg tissue, two tissues-liver and spleen-being monitored. Once sampled and processed ex vivo for their luciferin-dependent bioluminescence the threshold sensitivity was shown to range from 1,000 to 6,000 amastigotes/mg tissue. This model further proved to be valuable for in vivo measurement of the efficiency of drugs such as miltefosine and may, therefore, additionally be used to evaluate vaccine-induced protection.
authors.affiliation: Université de Nice-Sophia Antipolis, Faculté de Médecine, Nice, France. gmichel@unice.fr
authors.forename: Grégory
authors.initials: G
authors.lastname: Michel
authors.forename: Bernard
authors.initials: B
authors.lastname: Ferrua
authors.forename: Thierry
authors.initials: T
authors.lastname: Lang
authors.forename: Madhavi P
authors.initials: MP
authors.lastname: Maddugoda
authors.forename: Patrick
authors.initials: P
authors.lastname: Munro
authors.forename: Christelle
authors.initials: C
authors.lastname: Pomares
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Lemichez
authors.forename: Pierre
authors.initials: P
authors.lastname: Marty
mesh_terms: D000818:Animals; D000981:Antiprotozoal Agents / Q000494:pharmacology; D004353:Drug Evaluation, Preclinical / Q000379:methods; D005260:Female; D018314:Leishmania infantum / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D007898:Leishmaniasis, Visceral / Q000188:drug therapy / Q000469:parasitology; D008018:Life Cycle Stages; D008099:Liver / Q000469:parasitology; D008156:Luciferases / Q000032:analysis* / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D008163:Luminescent Measurements; D051379:Mice; D008807:Mice, Inbred BALB C; D030781:Organisms, Genetically Modified; D059208:Parasite Load / Q000379:methods*; D010767:Phosphorylcholine / Q000031:analogs & derivatives / Q000494:pharmacology; D015800:Protozoan Proteins; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013057:Spectrum Analysis / Q000379:methods; D013154:Spleen / Q000469:parasitology; D018709:Statistics, Nonparametric; D051598:Whole Body Imaging
chemical_list: D000981:Antiprotozoal Agents; D015800:Protozoan Proteins; D010767:Phosphorylcholine; C039128:miltefosine; D008156:Luciferases