Relationship Between Pneumocystis carinii Burden and the Degree of Host Immunosuppression in an Airborne Transmission Experimental Model.
To quantitatively assess the risk of contamination by Pneumocystis depending on the degree of immunosuppression (ID) of the exposed rat hosts, we developed an animal model, where rats went through different doses of dexamethasone. Then, natural and aerial transmission of Pneumocystis carinii occurred during cohousing of the rats undergoing gradual ID levels (receivers) with nude rats developing pneumocystosis (seeders). Following contact between receiver and seeder rats, the P. carinii burden of receiver rats was determined by toluidine blue ortho staining and by qPCR targeting the dhfr monocopy gene of this fungus. In this rat model, the level of circulating CD4(+) and CD8(+) T lymphocytes remained significantly stable and different for each dose of dexamethasone tested, thus reaching the goal of a new stable and gradual ID rat model. In addition, an inverse relationship between the P. carinii burden and the level of circulating CD4(+) or CD8(+) T lymphocytes was evidenced. This rat model may be used to study other opportunistic pathogens or even co-infections in a context of gradual ID.
Biology and Diversity of Emerging Eukaryotic Pathogens (BDPEE), Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France.|Health and Environment Microbiology Laboratory, AZM Center for Research in Biotechnology and its Application, Doctoral School of Sciences and Technology, Lebanese University, Tripoli, Lebanon.
Sara
S
Khalife
Biology and Diversity of Emerging Eukaryotic Pathogens (BDPEE), Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France.|Department of Parasitology, Faculty of Pharmacy of Lille, Univ. Lille, F-59000, Lille, France.
Magali
M
Chabé
Biology and Diversity of Emerging Eukaryotic Pathogens (BDPEE), Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France.
Nausicaa
N
Gantois
GENES DIFFUSION, Douai, France.|PEGASE-Biosciences, F-59000, Lille, France.
Christophe
C
Audebert
Biology and Diversity of Emerging Eukaryotic Pathogens (BDPEE), Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France.|Department of Parasitology, Faculty of Pharmacy of Lille, Univ. Lille, F-59000, Lille, France.
Muriel
M
Pottier
Health and Environment Microbiology Laboratory, AZM Center for Research in Biotechnology and its Application, Doctoral School of Sciences and Technology, Lebanese University, Tripoli, Lebanon.
Sani
S
Hlais
EA2694, Department of Biostatistics, Faculty of Pharmacy of Lille, Univ. Lille, F-59000, Lille, France.
Claire
C
Pinçon
Animal Unit, Pasteur Institute of Lille, F-59000, Lille, France.
Thierry
T
Chassat
Molecular Signaling and the Control of Parasite Growth and Differentiation, Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France.
Christine
C
Pierrot
Molecular Signaling and the Control of Parasite Growth and Differentiation, Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France.
Jamal
J
Khalife
Biology and Diversity of Emerging Eukaryotic Pathogens (BDPEE), Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France.|Department of Parasitology, Faculty of Pharmacy of Lille, Univ. Lille, F-59000, Lille, France.
Cécile-Marie
CM
Aliouat-Denis
Biology and Diversity of Emerging Eukaryotic Pathogens (BDPEE), Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France.|Department of Parasitology, Faculty of Pharmacy of Lille, Univ. Lille, F-59000, Lille, France.|Molecular Signaling and the Control of Parasite Growth and Differentiation, Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Center for Infection and Immunity of Lille, F-59000, Lille, France.
El Moukhtar
el M
Aliouat
D000336:Aerosols; D000391:Air Microbiology; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D015169:Colony Count, Microbial; D003907:Dexamethasone / Q000008:administration & dosage; D004195:Disease Models, Animal; D005800:Genes, Fungal; D016867:Immunocompromised Host; D008168:Lung / Q000382:microbiology; D008297:Male; D045363:Pneumocystis carinii / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology*; D011020:Pneumonia, Pneumocystis / Q000382:microbiology* / Q000635:transmission*; D051381:Rats
D000336:Aerosols; D003907:Dexamethasone
CD4+ T lymphocytes; CD8+ T lymphocytes; Pneumocystosis; colonization; fungal load