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In vitro and in vivo activity of iclaprim, a diaminopyrimidine compound and potential therapeutic alternative against Pneumocystis pneumonia. Eur J Clin Microbiol Infect Dis 2018; 37:409-415. [DOI: 10.1007/s10096-018-3184-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 01/02/2018] [Indexed: 01/30/2023]
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Benamrouz S, Guyot K, Gazzola S, Mouray A, Chassat T, Delaire B, Chabé M, Gosset P, Viscogliosi E, Dei-Cas E, Creusy C, Conseil V, Certad G. Cryptosporidium parvum infection in SCID mice infected with only one oocyst: qPCR assessment of parasite replication in tissues and development of digestive cancer. PLoS One 2012; 7:e51232. [PMID: 23272093 PMCID: PMC3521773 DOI: 10.1371/journal.pone.0051232] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2012] [Accepted: 10/31/2012] [Indexed: 12/01/2022] Open
Abstract
Dexamethasone (Dex) treated Severe Combined Immunodeficiency (SCID) mice were previously described as developing digestive adenocarcinoma after massive infection with Cryptosporidium parvum as soon as 45 days post-infection (P.I.). We aimed to determine the minimum number of oocysts capable of inducing infection and thereby gastrointestinal tumors in this model. Mice were challenged with calibrated oocyst suspensions containing intended doses of: 1, 10, 100 or 105 oocysts of C. parvum Iowa strain. All administered doses were infective for animals but increasing the oocyst challenge lead to an increase in mice infectivity (P = 0.01). Oocyst shedding was detected at 7 days P.I. after inoculation with more than 10 oocysts, and after 15 days in mice challenged with one oocyst. In groups challenged with lower inocula, parasite growth phase was significantly higher (P = 0.005) compared to mice inoculated with higher doses. After 45 days P.I. all groups of mice had a mean of oocyst shedding superior to 10,000 oocyst/g of feces. The most impressive observation of this study was the demonstration that C. parvum-induced digestive adenocarcinoma could be caused by infection with low doses of Cryptosporidium, even with only one oocyst: in mice inoculated with low doses, neoplastic lesions were detected as early as 45 days P.I. both in the stomach and ileo-caecal region, and these lesions could evolve in an invasive adenocarcinoma. These findings show a great amplification effect of parasites in mouse tissues after challenge with low doses as confirmed by quantitative PCR. The ability of C. parvum to infect mice with one oocyst and to develop digestive adenocarcinoma suggests that other mammalian species including humans could be also susceptible to this process, especially when they are severely immunocompromised.
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Affiliation(s)
- Sadia Benamrouz
- Laboratoire Environnement & Santé, Faculté Libre des Sciences et Technologies de Lille, Université Lille Nord de France, Lille, France
- Laboratoire de Biologie et Diversité des Pathogènes Eucaryotes Emergents, Centre d'Infection et d'Immunité de Lille, Institut Pasteur de Lille, INSERM U1019, CNRS UMR 8402, Université Lille Nord de France, Lille, France
| | - Karine Guyot
- Laboratoire de Biologie et Diversité des Pathogènes Eucaryotes Emergents, Centre d'Infection et d'Immunité de Lille, Institut Pasteur de Lille, INSERM U1019, CNRS UMR 8402, Université Lille Nord de France, Lille, France
| | - Sophie Gazzola
- Laboratoire de Biologie et Diversité des Pathogènes Eucaryotes Emergents, Centre d'Infection et d'Immunité de Lille, Institut Pasteur de Lille, INSERM U1019, CNRS UMR 8402, Université Lille Nord de France, Lille, France
| | - Anthony Mouray
- Plateforme d'Expérimentations et de Hautes Technologies Animales, Institut Pasteur de Lille, Lille, France
| | - Thierry Chassat
- Plateforme d'Expérimentations et de Hautes Technologies Animales, Institut Pasteur de Lille, Lille, France
| | - Baptiste Delaire
- Service d'Anatomie et de Cytologie Pathologiques, Groupe Hospitalier de l'Université Catholique de Lille, Université Lille Nord de France, Lille, France
| | - Magali Chabé
- Laboratoire de Biologie et Diversité des Pathogènes Eucaryotes Emergents, Centre d'Infection et d'Immunité de Lille, Institut Pasteur de Lille, INSERM U1019, CNRS UMR 8402, Université Lille Nord de France, Lille, France
- Faculté de Pharmacie, Université Lille Nord de France, Lille, France
| | - Pierre Gosset
- Service d'Anatomie et de Cytologie Pathologiques, Groupe Hospitalier de l'Université Catholique de Lille, Université Lille Nord de France, Lille, France
| | - Eric Viscogliosi
- Laboratoire de Biologie et Diversité des Pathogènes Eucaryotes Emergents, Centre d'Infection et d'Immunité de Lille, Institut Pasteur de Lille, INSERM U1019, CNRS UMR 8402, Université Lille Nord de France, Lille, France
| | - Eduardo Dei-Cas
- Laboratoire de Biologie et Diversité des Pathogènes Eucaryotes Emergents, Centre d'Infection et d'Immunité de Lille, Institut Pasteur de Lille, INSERM U1019, CNRS UMR 8402, Université Lille Nord de France, Lille, France
- Laboratoire de Parasitologie-Mycologie, Centre de Biologie et Pathologie, Centre Hospitalier Régional et Universitaire de Lille & Faculté de Médicine de Lille, Université Lille Nord de France, Lille, France
| | - Colette Creusy
- Service d'Anatomie et de Cytologie Pathologiques, Groupe Hospitalier de l'Université Catholique de Lille, Université Lille Nord de France, Lille, France
| | - Valerie Conseil
- Laboratoire Environnement & Santé, Faculté Libre des Sciences et Technologies de Lille, Université Lille Nord de France, Lille, France
- Laboratoire de Biologie et Diversité des Pathogènes Eucaryotes Emergents, Centre d'Infection et d'Immunité de Lille, Institut Pasteur de Lille, INSERM U1019, CNRS UMR 8402, Université Lille Nord de France, Lille, France
| | - Gabriela Certad
- Laboratoire de Biologie et Diversité des Pathogènes Eucaryotes Emergents, Centre d'Infection et d'Immunité de Lille, Institut Pasteur de Lille, INSERM U1019, CNRS UMR 8402, Université Lille Nord de France, Lille, France
- * E-mail:
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Choukri F, Aliouat EM, Menotti J, Totet A, Gantois N, Garin YJF, Bergeron V, Dei-cas E, Derouin F. Dynamics of Pneumocystis carinii Air Shedding During Experimental Pneumocystosis. J Infect Dis 2011; 203:1333-6. [DOI: 10.1093/infdis/jir018] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Certad G, Creusy C, Ngouanesavanh T, Guyot K, Gantois N, Mouray A, Chassat T, Flament N, Fleurisse L, Pinon A, Delhaes L, Dei-Cas E. Development of Cryptosporidium parvum-induced gastrointestinal neoplasia in severe combined immunodeficiency (SCID) mice: severity of lesions is correlated with infection intensity. Am J Trop Med Hyg 2010; 82:257-65. [PMID: 20134002 DOI: 10.4269/ajtmh.2010.09-0309] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
We reported previously that Cryptosporidium parvum was able to induce intestinal tumors in severe combined immunodeficiency (SCID) mice treated with corticoids. To further characterize this Cryptosporidium-induced cell transformation, SCID mice treated with dexamethasone were challenged with C. parvum oocysts, and euthanatized sequentially after infection for histologic examination. Ki-67 was used as a marker of cellular proliferation. Our previous results were confirmed, and it was also found that mice receiving higher inocula (10(6)-10(7)) experienced more severe neoplastic development. Additionally, neoplastic changes were observed not only in the caecum but also in the stomach and duodenum of some animals. Interestingly, SCID mice (6/6) inoculated with 10(5)-10(7) oocysts showed high grade intraepithelial neoplasia or adenomas with high grade dysplasia in the caecum after Day 46 post-infection (PI). Immunohistochemistry for Ki-67 staining indicated the neoplastic process associated to cryptosporidiosis, and evidenced the first immunohistochemical alterations at early stages of the process, even at 3 weeks PI.
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Affiliation(s)
- Gabriela Certad
- Ecologie du Parasitisme (EA3609 Université de Lille 2), IFR 142, Institut Pasteur de Lille, Lille, France.
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Respaldiza N, Medrano FJ, Medrano AC, Varela JM, de la Horra C, Montes-Cano M, Ferrer S, Wichmann I, Gargallo-Viola D, Calderon EJ. High seroprevalence of Pneumocystis infection in Spanish children. Clin Microbiol Infect 2004; 10:1029-31. [PMID: 15522012 DOI: 10.1111/j.1469-0691.2004.00974.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Pneumocystis infection occurs worldwide, and most individuals test seropositive for Pneumocystis early in childhood. Little is known about the epidemiology of this infection in western Europe. The seroprevalence of Pneumocystis infection in 233 Spanish children was determined in a community study by immunoblot analysis of sera. The overall seroprevalence was 73%, with an age-related increase from 52% at 6 years to 66% at 10 years and 80% at 13 years. The data indicated a high seroprevalence of Pneumocystis infection in healthy Spanish children, thereby demonstrating that this pathogen is widespread in southern Spain.
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Affiliation(s)
- N Respaldiza
- Research Unit, Virgen del Rocio University Hospital, Seville, Spain
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Thullen TD, Ashbaugh AD, Daly KR, Linke MJ, Steele PE, Walzer PD. New rat model of Pneumocystis pneumonia induced by anti-CD4(+) T-lymphocyte antibodies. Infect Immun 2003; 71:6292-7. [PMID: 14573648 PMCID: PMC219604 DOI: 10.1128/iai.71.11.6292-6297.2003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The CD4(+) T lymphocyte plays a central role in host defense against Pneumocystis pneumonia but has received only limited attention in rats. CD4(+) T-cell-depleting (OX-38) and nondepleting (W3/25) monoclonal antibodies, which recognize an identical or adjacent epitope, were administered for up to 14 weeks to Lewis rats that had been exposed to PNEUMOCYSTIS: While OX-38 produced a greater decrease in circulating CD4(+) cells than W3/25, both antibody treatments resulted in similar effects on the health of the rats and the levels of Pneumocystis pneumonia, which were milder than those found with corticosteroids. W3/25 also did not enhance the severity of Pneumocystis pneumonia achieved with corticosteroids alone. We conclude that CD4(+) cell function is more important than CD4(+) cell number in host defense against Pneumocystis in the rat and that this new model permits study of opportunistic infections in the rat without the confounding effects of corticosteroids.
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Affiliation(s)
- Timothy D Thullen
- Veterans Affairs Medical Center, University of Cincinnati College of Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45220, USA
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Medrano FJ, Respaldiza N, Medrano A, Varela JM, Montes-Cano M, de la Horra C, Wichmann I, Ferrer S, Calderón E. Seroprevalence of Pneumocystis Human Infection in Southern Spain. J Eukaryot Microbiol 2003; 50 Suppl:649-50. [PMID: 14736202 DOI: 10.1111/j.1550-7408.2003.tb00669.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Francisco J Medrano
- Department of Internal Medicine, Virgen del Rocio University Hospital, Seville, Spain.
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Abstract
Pneumocystis organisms can cause pneumonia in mammals that lack a strong immune defense. The genus Pneumocystis contains many different organisms that can be distinguished by DNA sequence analysis. These different organisms are different species of yeast-like fungi that are most closely related to the ascomycete, Schizosaccharomyces pombe. Each species of Pneumocystis appears to be specific for the mammal in which it is found. The species that infects humans is Pneumocystis jiroveci. P. jiroveci has not been found in any other mammal and the species of Pneumocystis found in other mammals have not been seen in humans. Genetic variation among P. jiroveci samples is common, suggesting that there are many strains. Strain analysis shows that adults can be infected by more than one strain, and suggests that pneumonia can be the result of infection occurring proximal to the time of disease, rather than to reactivation of dormant organisms acquired in early childhood. Nevertheless, long-term colonisation may be occurring. A large fraction of normal children and animals show evidence of infection. A Pneumocystis species that grows in rats has been shown to possess a complex genetic system for surface antigen variation, a strategy employed by other microbes that dwell in immunocompetent hosts. These findings, together with strong host specificity, suggest that Pneumocystis species may be obligate parasites. The source of infection is not clear. Pneumocystis DNA is detectable in the air, but is scarce except in environments occupied by individuals with Pneumocystis pneumonia. In a few cases, there is direct evidence of person to person transmission. In general, however, patients and their contacts have been found to have different strains of P. jiroveci.
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Affiliation(s)
- James R Stringer
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati, Cincinnati, OH 45220-0524, USA.
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Jimenez E, Martínez A, Aliouat EM, Caballero J, Dei-Cas E, Gargallo-Viola D. Therapeutic efficacies of GW471552 and GW471558, two new azasordarin derivatives, against pneumocystosis in two immunosuppressed-rat models. Antimicrob Agents Chemother 2002; 46:2648-50. [PMID: 12121948 PMCID: PMC127331 DOI: 10.1128/aac.46.8.2648-2650.2002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Two new azasordarins, GW471552 and GW471558, were studied in vivo for treatment of Pneumocystis carinii pneumonia. In the Wistar rat spontaneous pneumonia model, both azasordarins significantly reduced the number of P. carinii cysts per gram of lung homogenate when administered at 1 mg/kg of body weight twice a day for 10 days. In a nude rat inoculation model, both compounds showed therapeutic efficacy at 0.25 mg/kg twice a day for 10 days.
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Affiliation(s)
- Elena Jimenez
- GlaxoSmithKline, Technological Park of Madrid, Severo Ochoa 2, 28760 Tres Cantos, Madrid., Spain.
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Abstract
This article reviews the molecular genetic data pertaining to the major surface glycoprotein (MSG) gene family of Pneumocystis carinii and its role in surface variation and compares this fungal system to antigenic variation systems in the protozoan Trypanosoma brucei and the bacteria Borrelia spp.
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Affiliation(s)
- J R Stringer
- Department of Molecular Genetics, Biochemistry, and Microbiology, College of Medicine, University of Cincinnati, Cincinnati, Ohio 45267, USA.
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Martinez A, Aviles P, Jimenez E, Caballero J, Gargallo-Viola D. Activities of sordarins in experimental models of candidiasis, aspergillosis, and pneumocystosis. Antimicrob Agents Chemother 2000; 44:3389-94. [PMID: 11083645 PMCID: PMC90210 DOI: 10.1128/aac.44.12.3389-3394.2000] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sordarin derivatives represent a new class of antifungal agents that act as potent inhibitors of fungal protein synthesis and possess a broad spectrum of activity. The in vivo activity of GM193663 and GM237354 was studied in mouse models of disseminated candidiasis and aspergillosis and in a rat model of pneumocystosis. The pharmacokinetic behavior of both sordarin derivatives was studied in mice and rats. In all studies, compounds were administered by the subcutaneous route. After a subcutaneous dose of 50 mg/kg of body weight to mice, the maximum level in serum, area under the concentration-time curve, half-life, and clearance for GM193663 and GM237354 were 51.8 and 23 microg/ml, 79.5 and 46 microg. h/ml, 0.8 and 0.85 h, and 21 and 25 ml/h, respectively. Systemic candidiasis and aspergillosis were established in CD-1 male mice infected with Candida albicans or Aspergillus fumigatus. For systemic candidiasis, compounds were given three times per day for seven consecutive days at 15, 30, 60, or 120 mg/kg/day. GM193663 and GM237354 showed dose-related efficacy against C. albicans, with 50% effective doses, 1 month after infection, of 25.2 and 10.7 mg/kg/dose, respectively. In experimental infections with A. fumigatus, GM237354 was given three times per day at 30, 60, or 120 mg/kg/day for five consecutive days. Animals treated with GM237354 demonstrated irregular responses. The survival of animals treated with GM237354 was 0, 30, and 0% at 30, 60, and 120 mg/kg/day, respectively. The therapeutic efficacy of GM193663 and GM237354 against Pneumocystis carinii was studied in an experimental P. carinii pneumonia (PCP) rat model. After a subcutaneous dose of 10 mg/kg given to rats, the maximum level in serum, area under the concentration-time curve, half-life, and clearance for GM193663 and GM237354 were 6.6 and 7.2 microg/ml, 8.5 and 11.8 microg. h/ml, 0.7 and 0.8 h, and 230 and 133 ml/h, respectively. To induce spontaneous PCP, rats were chronically immunosuppressed with dexamethasone. Infected animals were treated twice daily for 10 days at 0.2, 2, or 10 mg/kg/day. The therapeutic effect was estimated by the reduction in the number of cysts in the lungs of treated versus untreated animals. GM193663 and GM237354 significantly reduced the mean (+/- standard deviation) log number of cysts from 7.6 +/- 0.2 in the untreated group to 4.7 +/- 0.2 and 4.6 +/- 0.1, respectively, when the drugs were administered at a dose of 2 mg/kg/day. The log number of cysts was also reduced in infected animals given lower doses of the compounds (0.2 mg/kg/day). In summary, GM193663 and GM237354 are new sordarin derivatives that may potentially play a major role in the treatment of candidiasis and PCP. Further testing with Aspergillus in other animal models is warranted.
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Affiliation(s)
- A Martinez
- Research Department, Glaxo Wellcome S.A., 28760 Tres Cantos, Madrid, Spain
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Aviles P, Aliouat EM, Martinez A, Dei-Cas E, Herreros E, Dujardin L, Gargallo-Viola D. In vitro pharmacodynamic parameters of sordarin derivatives in comparison with those of marketed compounds against Pneumocystis carinii isolated from rats. Antimicrob Agents Chemother 2000; 44:1284-90. [PMID: 10770763 PMCID: PMC89856 DOI: 10.1128/aac.44.5.1284-1290.2000] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pneumocystis carinii pneumonia remains one of the most serious complications of immunosuppressed patients. In this study, the in vitro pharmacodynamic parameters of four sordarin derivatives (GM 191519, GM 237354, GM 193663, and GM 219771) have been evaluated by a new quantitative approach and compared with the commercially available drugs pentamidine, atovaquone, and trimethoprim-sulfamethoxazole (TMP-SMX). In vitro activities and in vivo therapeutic efficacies of sordarin derivatives against P. carinii were also evaluated. In vitro activity was determined by the broth microdilution technique, comparing the total number of microorganisms in treated and drug-free cultures by using Giemsa staining. The in vitro maximum effect (E(max)), the drug concentrations to reach 50% of E(max) (EC(50)), and the slope of the dose-response curve were then estimated by the Hill equation (E(max) sigmoid model). Sordarin derivatives were the most potent agents against P. carinii, with EC(50)s of 0.00025, 0.0007, 0.0043, and 0. 025 microg/ml for GM 191519, GM 237354, GM 193663, and GM 219771, respectively. The EC(50)s of pentamidine, atovaquone, and TMP-SMX were 0.025, 0.16, and 26.7/133.5 microg/ml, respectively. The results obtained with this approach showed GM 237354 and GM 191519 to be approximately 35- and 100-fold more active in vitro than pentamidine, the most active marketed compound. All sordarin derivatives tested were at least 5,000-fold more active in vitro than TMP-SMX. The three sordarin derivatives tested in vivo-GM 191519, GM 237354, and GM 219771-showed a marked therapeutic efficacy, defined as reduction of cyst forms per gram of lung. GM 191519 was the most potent (daily dose reducing 50% of the P. carinii burden in the lungs [ED(50)], 0.05 mg/kg/day) followed by GM 237354 and GM 219771 (ED(50)s, 0.30 and 0.49 mg/kg/day, respectively). Good agreement between in vitro parameters and in vivo outcome was obtained when P. carinii pneumonia in rats was treated with sordarin derivatives.
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Affiliation(s)
- P Aviles
- Department of Chemotherapy, GlaxoWellcome, S.A., Madrid, Spain
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Dei-Cas E, Brun-Pascaud M, Bille-Hansen V, Allaert A, Aliouat EM. Animal models of pneumocystosis. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 1998; 22:163-8. [PMID: 9792075 DOI: 10.1111/j.1574-695x.1998.tb01201.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
As in vitro culture systems allowing to isolate Pneumocystis samples from patients or other mammal hosts are still not available, animal models have critical importance in Pneumocystis research. The parasite was reported in numerous mammals but P. carinii pneumonia (PCP) experimental models were essentially developed by using rats, mice, rabbits and ferrets. The rat treated with corticosteroids for 9-12 weeks is a useful PCP model. Like laboratory rats, conventional mice develop PCP after prolonged corticosteroid administration. The ferret (Mustela putorius furo) also develop PCP under corticosteroid regime. Whilst bronchoalveolar lavage (BAL) is really difficult to perform on live laboratory rodents, serial BAL sampling can be performed on live ferrets. Rabbits currently develop spontaneous PCP at weaning without corticosteroid administration. For this reason this model has been used for studying the host immune response as well as Pneumocystis-surfactant interactions. Pigs and horses also develop spontaneous PCP. Treated with corticosteroids, piglets develop extensive PCP and could be used as a non-rodent model. Pneumocystis was detected in many non-human primates. Primates could represent a source of parasites taxonomically related to P. carinii sp. f. hominis. Moreover, primates might be used as experimental hosts to human Pneumocystis. A marked variability of parasite levels among corticosteroid-treated animals and the fact that the origin of the parasite strain remains unknown, are important drawbacks of the corticosteroid-treated models. For these reasons, inoculated animal models of PCP were developed. The intratracheal inoculation of lung homogenates containing viable parasites in corticosteroid-treated non-latently infected rats resulted in extensive, reproducible Pneumocystis infections. Extensive PCP can be obtained within 5-7 weeks, whilst 9-12 weeks are needed in the classical model. The severe combined immunodeficiency (SCID) mouse inoculated by nasal route and the athymic nude rats intratracheally inoculated were used to test the infectivity of Pneumocystis samples coming from cultures or from different hosts. They were also used to test the anti-Pneumocystis activity of antimicrobial molecules.
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Affiliation(s)
- E Dei-Cas
- Faculty of Medicine and Regional University Hospital Centre, Lille, France.
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