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Obaldía N, Da Silva Filho JL, Núñez M, Glass KA, Oulton T, Achcar F, Wirjanata G, Duraisingh M, Felgner P, Tetteh KK, Bozdech Z, Otto TD, Marti M. Sterile protection against P. vivax malaria by repeated blood stage infection in the Aotus monkey model. Life Sci Alliance 2024; 7:e202302524. [PMID: 38158220 PMCID: PMC10756917 DOI: 10.26508/lsa.202302524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024] Open
Abstract
The malaria parasite Plasmodium vivax remains a major global public health challenge, and no vaccine is approved for use in humans. Here, we assessed whether P. vivax strain-transcendent immunity can be achieved by repeated infection in Aotus monkeys. Sterile immunity was achieved after two homologous infections, whereas subsequent heterologous challenge provided only partial protection. IgG levels based on P. vivax lysate ELISA and protein microarray increased with repeated infections and correlated with the level of homologous protection. Parasite transcriptional profiles provided no evidence of major antigenic switching upon homologous or heterologous challenge. However, we observed significant sequence diversity and transcriptional differences in the P. vivax core gene repertoire between the two strains used in the study, suggesting that partial protection upon heterologous challenge is due to molecular differences between strains rather than immune evasion by antigenic switching. Our study demonstrates that sterile immunity against P. vivax can be achieved by repeated homologous blood stage infection in Aotus monkeys, thus providing a benchmark to test the efficacy of candidate blood stage P. vivax malaria vaccines.
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Affiliation(s)
- Nicanor Obaldía
- Departamento de Investigaciones en Parasitologia, Instituto Conmemorativo Gorgas de Estudios de la Salud, Panamá City, Republic of Panamá
- Department of Immunology and Infectious Diseases, Harvard TH Chan School of Public Health, Harvard University, Boston, MA, USA
- https://ror.org/00vtgdb53 Wellcome Centre for Integrative Parasitology, School of Infection and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Joao Luiz Da Silva Filho
- https://ror.org/00vtgdb53 Wellcome Centre for Integrative Parasitology, School of Infection and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
- https://ror.org/02crff812 Institute of Parasitology, Vetsuisse and Medical Faculty, University of Zurich, Zurich, Switzerland
| | - Marlon Núñez
- Departamento de Investigaciones en Parasitologia, Instituto Conmemorativo Gorgas de Estudios de la Salud, Panamá City, Republic of Panamá
| | - Katherine A Glass
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, UK
| | - Tate Oulton
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, UK
| | - Fiona Achcar
- https://ror.org/00vtgdb53 Wellcome Centre for Integrative Parasitology, School of Infection and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
- https://ror.org/02crff812 Institute of Parasitology, Vetsuisse and Medical Faculty, University of Zurich, Zurich, Switzerland
| | - Grennady Wirjanata
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Manoj Duraisingh
- Department of Immunology and Infectious Diseases, Harvard TH Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Philip Felgner
- Institute for Immunology, University of California, Irvine, CA, USA
| | - Kevin Ka Tetteh
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, UK
| | - Zbynek Bozdech
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Thomas D Otto
- https://ror.org/00vtgdb53 Wellcome Centre for Integrative Parasitology, School of Infection and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Matthias Marti
- Department of Immunology and Infectious Diseases, Harvard TH Chan School of Public Health, Harvard University, Boston, MA, USA
- https://ror.org/00vtgdb53 Wellcome Centre for Integrative Parasitology, School of Infection and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
- https://ror.org/02crff812 Institute of Parasitology, Vetsuisse and Medical Faculty, University of Zurich, Zurich, Switzerland
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Obaldía N, Barahona I, Lasso J, Avila M, Quijada M, Nuñez M, Marti M. Comparison of PvLAP5 and Pvs25 qRT-PCR assays for the detection of Plasmodium vivax gametocytes in field samples preserved at ambient temperature from remote malaria endemic regions of Panama. PLoS Negl Trop Dis 2022; 16:e0010327. [PMID: 35394999 PMCID: PMC9020738 DOI: 10.1371/journal.pntd.0010327] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 04/20/2022] [Accepted: 03/14/2022] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND As the elimination of malaria in Mesoamerica progresses, detection of Plasmodium vivax using light microscopy (LM) becomes more difficult. Highly sensitive molecular tools have been developed to help determine the hidden reservoir of malaria transmission in low transmission settings. In this study we compare the performance of PvLAP5 and Pvs25 qRT-PCR assays to LM for the detection of Plasmodium vivax gametocytes in field samples preserved at ambient temperature from malaria endemic regions of Panama. METHODS For this purpose, we collected a total of 83 malaria field samples during 2017-2020 preserved in RNAprotect (RNAp) of which 63 (76%) were confirmed P. vivax by LM and selected for further analysis. Additionally, 16 blood samples from local healthy malaria smear negative volunteers, as well as, from 15 malaria naïve lab-bred Aotus monkeys were used as controls. To optimize the assays, we first determined the minimum blood volume sufficient for detection of PvLAP5 and Pv18SrRNA using P. vivax infected Aotus blood that was preserved in RNAp and kept either at ambient temperature for up to 8 days before freezing or was snap-frozen at -80° Celsius at the time of bleeding. We then compared the mean differences in gametocyte detection rates of both qRT-PCR assays to LM and performed a multivariate correlation analysis of study variables. Finally, we determined the sensitivity (Se) and specificity (Sp) of the assays at detecting gametocytes compared to LM. RESULTS Blood volume optimization indicated that a blood volume of at least 60 μL was sufficient for detection of PvLAP5 and Pv18SrRNA and no significant differences were found between RNA storage conditions. Both PvLAP5 and Pvs25 qRT-PCR assays showed a 37-39% increase in gametocyte detection rate compared to LM respectively. Strong positive correlations were found between gametocytemia and parasitemia and both PvLAP5 and Pvs25 gametocyte markers. However, no significant differences were detected in the Se and Sp of the Pvs25 and PvLAP5 qRT-PCR assays, even though data from control samples suggested Pvs25 to be more abundant than PvLAP5. CONCLUSIONS This study shows that the PvLAP5 qRT-PCR assay is as Se and Sp as the gold standard Pvs25 assay and is at least 37% more sensitive than LM at detecting P. vivax gametocytes in field samples preserved in RNAp at ambient temperature from malaria endemic regions of Panama. AUTHOR SUMMARY Plasmodium vivax is one of the five species of malaria (P. falciparum, P. malariae, P. ovale and P. knowlesi) that are transmitted to man by the bite of female anopheles mosquitoes. It causes ~14.3 million cases mainly in Southeast Asia, India, the Western Pacific and the Americas annually. In the Americas, malaria remains a major problem in underdeveloped areas and indigenous communities in the Amazon region and eastern Panama, where it is endemic and difficult to eliminate. As malaria elimination progresses, detection of P. vivax by light microscopy (LM) becomes more difficult. Therefore, highly sensitive molecular tools have been developed that use genetic markers for the parasite to help determine the hidden reservoir of malaria transmission. This study compares the performance of two molecular assays based on the genetic markers of mature gametocytes PvLAP5 and Pvs25 with LM. The study shows that the PvLAP5 qRT-PCR assay is as sensitive and specific as the gold standard Pvs25 assay and is at least 37% more sensitive than LM at detecting P. vivax gametocytes. These data suggest that the PvLAP5 qRT-PCR assay can be a useful tool to help determine the hidden reservoir of transmission in endemic foci approaching elimination.
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Affiliation(s)
- Nicanor Obaldía
- Departamento de Investigaciones en Parasitología, Instituto Conmemorativo Gorgas de Estudios de la Salud, Panamá City, Panamá, Republic of Panamá
- Department of Immunology and Infectious Diseases, Harvard T.H. CHAN School of Public Health, Boston, Massachusetts, United States of America
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom
| | - Itza Barahona
- Departamento de Control de Vectores, Dirección General de Salud Pública, Ministerio de Salud de Panamá, Panamá, Republic of Panamá
| | - José Lasso
- Departamento de Control de Vectores, Dirección General de Salud Pública, Ministerio de Salud de Panamá, Panamá, Republic of Panamá
| | - Mario Avila
- Departamento de Control de Vectores, Dirección General de Salud Pública, Ministerio de Salud de Panamá, Panamá, Republic of Panamá
| | - Mario Quijada
- Departamento de Investigaciones en Parasitología, Instituto Conmemorativo Gorgas de Estudios de la Salud, Panamá City, Panamá, Republic of Panamá
| | - Marlon Nuñez
- Departamento de Investigaciones en Parasitología, Instituto Conmemorativo Gorgas de Estudios de la Salud, Panamá City, Panamá, Republic of Panamá
| | - Matthias Marti
- Department of Immunology and Infectious Diseases, Harvard T.H. CHAN School of Public Health, Boston, Massachusetts, United States of America
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, Scotland, United Kingdom
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Obaldía N, Nuñez M. On the survival of 48 h Plasmodium vivax Aotus monkey-derived ex vivo cultures: the role of leucocytes filtration and chemically defined lipid concentrate media supplementation. Malar J 2020; 19:278. [PMID: 32746814 PMCID: PMC7398384 DOI: 10.1186/s12936-020-03348-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 07/25/2020] [Indexed: 11/10/2022] Open
Abstract
Background Filtration of leukocytes (WBCs) is a standard practice of malaria ex vivo cultures. To date, few studies have considered the effect of filtration or the lack thereof on the survival of Plasmodium vivax ex vivo cultures through one cycle of maturation. This study investigates the effect of WBC filtration and culture media supplementation on the survival of 48–72 h ex vivo cultures. Methods Using parasitaemia density, the study compares the survival of Plasmodipur® filtered, filter-retained or washed ex vivo cultures, maintained with McCoy’s5A medium supplemented with 25% serum alone or 20% in combination with 5% chemically defined lipid concentrate (CDLC), and in washed ex vivo cultures plus GlutaMAX™, benchmarked against IMDM™ or AIM-V™ media; also, assessed the survival of ex vivo cultures co-cultivated with human red blood cells (hRBCs). Results After 48 h of incubation a statistically significant difference was detected in the survival proportions of filtered and the filter-retained ex vivo cultures supplemented with serum plus CDLC (p = 0.0255), but not with serum alone (p = 0.1646). To corroborate these finding, parasitaemias of washed ex vivo cultures maintained with McCoy’s5A complete medium were benchmarked against IMDM™ or AIM-V™ media; again, a statistically significant difference was detected in the cultures supplemented with CDLC and GlutaMAX™ (p = 0.03), but not when supplemented with either alone; revealing a pattern of McCoy’s5A medium supplementation for Aotus-derived P. vivax cultures as follows: serum < serum + GlutaMAX™ < serum + CDLC < serum + CDLC + GlutaMAX™; confirming a key role of CDLC in combination with GlutaMAX™ in the enhanced survival observed. Lastly, results showed that co-cultivation with malaria-naïve hRBCs improved the survival of ex vivo cultures. Conclusions This study demonstrates that WBC filtration is not essential for the survival of P. vivax ex vivo cultures. It also demonstrates that McCoy’s5A complete medium improves the survival of Aotus-derived P. vivax ex vivo cultures, with no significant difference in survival compared to IMDM and AIM-V media. Finally, the study demonstrates that co-cultivation with hRBCs enhances the survival of ex vivo cultures. These findings are expected to help optimize seeding material for long-term P. vivax in vitro culture.
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Affiliation(s)
- Nicanor Obaldía
- Center for the Evaluation of Antimalarial Drugs and Vaccines, Tropical Medicine Research/Instituto Conmemorativo Gorgas de Estudios de la Salud, Panama city, Panama. .,Center for Global Health & Infectious Diseases Research, Department of Global Health, University of South Florida, Tampa, FL, USA. .,Department of Immunology and Infectious Diseases, Harvard, T.H. Chan School of Public Health, Boston, MA, USA.
| | - Marlon Nuñez
- Center for the Evaluation of Antimalarial Drugs and Vaccines, Tropical Medicine Research/Instituto Conmemorativo Gorgas de Estudios de la Salud, Panama city, Panama
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Obaldía N, Nuñez M, Montilla S, Otero W, Marin JC. Tuberculosis (TB) outbreak in a closed Aotus monkey breeding colony: Epidemiology, diagnosis and TB screening using antibody and interferon-gamma release testing. Comp Immunol Microbiol Infect Dis 2018; 58:1-10. [PMID: 30245044 DOI: 10.1016/j.cimid.2018.06.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 03/05/2018] [Accepted: 06/10/2018] [Indexed: 11/19/2022]
Abstract
Tuberculosis (TB) caused by Mycobacterium tuberculosis (MTB) is a devastating and terminal disease in non-human primates (NHPs). Regular TB screenings using the intradermal tuberculin test (TST) have been the mainstay of TB surveillance and control in NHPs. Historically, Aotus monkeys have been considered less susceptible to TB than other NHPs. Here we present the diagnosis and epidemiology of a TB outbreak at The Gorgas Memorial Institute Aotus colony in Panama, and the results of two cross-sectional randomized TB screening studies, using antibody (Ab) and IFN-gamma release assay testing. RESULTS Epidemiological and spatial analysis confirmed that the outbreak was the result of a continuing intermittent exposure, with human to monkey transmission as the most likely source. During the outbreak that lasted five months (January-June 2015), Mycobacterium kansassi and MTB were isolated from lung caseous granulomas in 1/7 and 3/7 TB suspicious animals respectively. Furthermore, MTB was detected by qRT-PCR in formalin fixed lung and liver granulomas in 2/7 and 1/6 monkeys respectively, suggesting an aerosol route of infection. Likewise, a random sample that included 63 / 313 adult (>2 year-old) monkeys, screened for latent TB with the Primagam® IFN-gamma release assay, between March-May, 2016, were all non-reactors; indicating that the outbreak was self-limiting and the colony was likely free or latent TB infection. Control measures included, quarantine, disinfection and TST screening of all personnel. In conclusion, this study demonstrates that Aotus are highly susceptible to TB, therefore, TB prevention measures should be strictly enforced in Aotus monkey colonies.
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Affiliation(s)
- Nicanor Obaldía
- Center for the Evaluation of Antimalarial Drugs and Vaccines, Tropical Medicine Research/Instituto Conmemorativo Gorgas de Estudios de la Salud, Panama, Panama; Department of Immunology and Infectious Diseases, Harvard | T.H Chan School of Public Health, Boston, MA, USA; Department of Parasitology, Instituto Conmemorativo Gorgas de Estudios de la Salud, Panama, Panama.
| | - Marlon Nuñez
- Department of Parasitology, Instituto Conmemorativo Gorgas de Estudios de la Salud, Panama, Panama
| | - Santiago Montilla
- Department of Parasitology, Instituto Conmemorativo Gorgas de Estudios de la Salud, Panama, Panama
| | - William Otero
- Center for the Evaluation of Antimalarial Drugs and Vaccines, Tropical Medicine Research/Instituto Conmemorativo Gorgas de Estudios de la Salud, Panama, Panama
| | - Jose Camilo Marin
- Center for the Evaluation of Antimalarial Drugs and Vaccines, Tropical Medicine Research/Instituto Conmemorativo Gorgas de Estudios de la Salud, Panama, Panama; Department of Parasitology, Instituto Conmemorativo Gorgas de Estudios de la Salud, Panama, Panama
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Shaw-Saliba K, Thomson-Luque R, Obaldía N, Nuñez M, Dutary S, Lim C, Barnes S, Kocken CHM, Duraisingh MT, Adams JH, Pasini EM. Insights into an Optimization of Plasmodium vivax Sal-1 In Vitro Culture: The Aotus Primate Model. PLoS Negl Trop Dis 2016; 10:e0004870. [PMID: 27463518 PMCID: PMC4963040 DOI: 10.1371/journal.pntd.0004870] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 06/30/2016] [Indexed: 01/03/2023] Open
Abstract
Malaria is one of the most significant tropical diseases, and of the Plasmodium species that cause human malaria, P. vivax is the most geographically widespread. However, P. vivax remains a relatively neglected human parasite since research is typically limited to laboratories with direct access to parasite isolates from endemic field settings or from non-human primate models. This restricted research capacity is in large part due to the lack of a continuous P. vivax in vitro culture system, which has hampered the ability for experimental research needed to gain biological knowledge and develop new therapies. Consequently, efforts to establish a long-term P. vivax culture system are confounded by our poor knowledge of the preferred host cell and essential nutrients needed for in vitro propagation. Reliance on very heterogeneous P. vivax field isolates makes it difficult to benchmark parasite characteristics and further complicates development of a robust and reliable culture method. In an effort to eliminate parasite variability as a complication, we used a well-defined Aotus-adapted P. vivax Sal-1 strain to empirically evaluate different short-term in vitro culture conditions and compare them with previous reported attempts at P. vivax in vitro culture Most importantly, we suggest that reticulocyte enrichment methods affect invasion efficiency and we identify stabilized forms of nutrients that appear beneficial for parasite growth, indicating that P. vivax may be extremely sensitive to waste products. Leuko-depletion methods did not significantly affect parasite development. Formatting changes such as shaking and static cultures did not seem to have a major impact while; in contrast, the starting haematocrit affected both parasite invasion and growth. These results support the continued use of Aotus-adapted Sal-1 for development of P. vivax laboratory methods; however, further experiments are needed to optimize culture conditions to support long-term parasite development.
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Affiliation(s)
- Kathryn Shaw-Saliba
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Richard Thomson-Luque
- Center for Global Health & Infectious Diseases Research, Department of Global Health, College of Public Health, University of South Florida, Tampa, Florida, United States of America
| | - Nicanor Obaldía
- Center for the Evaluation of Antimalarial Drugs and Vaccines, Tropical Medicine Research / Instituto Conmemorativo Gorgas de Estudios de la Salud, Panamá, Panamá
| | - Marlon Nuñez
- Center for the Evaluation of Antimalarial Drugs and Vaccines, Tropical Medicine Research / Instituto Conmemorativo Gorgas de Estudios de la Salud, Panamá, Panamá
| | - Sahir Dutary
- Center for the Evaluation of Antimalarial Drugs and Vaccines, Tropical Medicine Research / Instituto Conmemorativo Gorgas de Estudios de la Salud, Panamá, Panamá
| | - Caeul Lim
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Samantha Barnes
- Center for Global Health & Infectious Diseases Research, Department of Global Health, College of Public Health, University of South Florida, Tampa, Florida, United States of America
| | | | - Manoj T. Duraisingh
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
- * E-mail: (MTD); (JHA); (EMP)
| | - John H. Adams
- Center for Global Health & Infectious Diseases Research, Department of Global Health, College of Public Health, University of South Florida, Tampa, Florida, United States of America
- * E-mail: (MTD); (JHA); (EMP)
| | - Erica M. Pasini
- Biomedical Primate Research Centre, Rijswijk, The Netherlands
- * E-mail: (MTD); (JHA); (EMP)
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Obaldía N, Dow GS, Gerena L, Kyle D, Otero W, Mantel PY, Baro N, Daniels R, Mukherjee A, Childs LM, Buckee C, Duraisingh MT, Volkman SK, Wirth DF, Marti M. Altered drug susceptibility during host adaptation of a Plasmodium falciparum strain in a non-human primate model. Sci Rep 2016; 6:21216. [PMID: 26880111 PMCID: PMC4754742 DOI: 10.1038/srep21216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 01/19/2016] [Indexed: 01/07/2023] Open
Abstract
Infections with Plasmodium falciparum, the most pathogenic of the Plasmodium species affecting man, have been reduced in part due to artemisinin-based combination therapies. However, artemisinin resistant parasites have recently emerged in South-East Asia. Novel intervention strategies are therefore urgently needed to maintain the current momentum for control and elimination of this disease. In the present study we characterize the phenotypic and genetic properties of the multi drug resistant (MDR) P. falciparum Thai C2A parasite strain in the non-human Aotus primate model, and across multiple passages. Aotus infections with C2A failed to clear upon oral artesunate and mefloquine treatment alone or in combination, and ex vivo drug assays demonstrated reduction in drug susceptibility profiles in later Aotus passages. Further analysis revealed mutations in the pfcrt and pfdhfr loci and increased parasite multiplication rate (PMR) across passages, despite elevated pfmdr1 copy number. Altogether our experiments suggest alterations in parasite population structure and increased fitness during Aotus adaptation. We also present data of early treatment failures with an oral artemisinin combination therapy in a pre-artemisinin resistant P. falciparum Thai isolate in this animal model.
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Affiliation(s)
- Nicanor Obaldía
- Department of Immunology and Infectious Diseases, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States.,Center for the Evaluation of Antimalarial Drugs and Vaccines, Tropical Medicine Research/Instituto Conmemorativo Gorgas de Estudios de la Salud, Panamá City, Republic of Panama
| | - Geoffrey S Dow
- Walter Reed Army Institute of Research, Silver Springs, MD, United States
| | - Lucia Gerena
- Walter Reed Army Institute of Research, Silver Springs, MD, United States
| | - Dennis Kyle
- Department of Global Health, University of South Florida, Tampa, FL, United States
| | - William Otero
- Center for the Evaluation of Antimalarial Drugs and Vaccines, Tropical Medicine Research/Instituto Conmemorativo Gorgas de Estudios de la Salud, Panamá City, Republic of Panama
| | - Pierre-Yves Mantel
- Department of Immunology and Infectious Diseases, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States
| | - Nicholas Baro
- Department of Immunology and Infectious Diseases, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States
| | - Rachel Daniels
- Department of Immunology and Infectious Diseases, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States
| | - Angana Mukherjee
- Department of Immunology and Infectious Diseases, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States
| | - Lauren M Childs
- Center for Communicable Disease Dynamics and Harvard
- T.H. Chan School of Public Health, Boston, MA, United States.,Department of Epidemiology, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States
| | - Caroline Buckee
- Center for Communicable Disease Dynamics and Harvard
- T.H. Chan School of Public Health, Boston, MA, United States.,Department of Epidemiology, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States
| | - Manoj T Duraisingh
- Department of Immunology and Infectious Diseases, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States
| | - Sarah K Volkman
- Department of Immunology and Infectious Diseases, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States.,The Broad Institute of MIT and Harvard, Cambridge, MA, United States.,School of Nursing and Health Sciences, Simmons College, Boston, MA United States
| | - Dyann F Wirth
- Department of Immunology and Infectious Diseases, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States.,The Broad Institute of MIT and Harvard, Cambridge, MA, United States
| | - Matthias Marti
- Department of Immunology and Infectious Diseases, Harvard
- T.H. Chan School of Public Health, Boston, MA, United States
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Obaldía N, Milhous W, Kyle D. Adaptation of a Thai multidrug-resistant C2A clone of Plasmodium falciparum to Aotus monkeys and its preliminary in vivo antimalarial drug efficacy-resistance profile. Am J Trop Med Hyg 2009; 81:587-94. [PMID: 19815871 DOI: 10.4269/ajtmh.2009.08-0445] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
A multidrug-resistant (MDR) clone of Plasmodium falciparum (C2A) from Thailand was adapted through serial passage to Aotus monkeys. During adaptation, the parasite showed resistance to a single 20 or 40 mg/kg oral dose of mefloquine (MQ). Infection was only cured when MQ was administered orally at 40 mg/kg once in combination with intravenous artesunic acid at 20 mg/kg for 3 days. Similarly, the parasite clone was found to be resistant to quinine, failing at 20 mg/kg orally for 5 days in combination with an experimental dihydrofolate reductase (DHFR) inhibitor (WR297608) at 10, 20, or 40 mg/kg orally for 3 days, and with atovaquone/proguanil at 25 mg/kg for 3 days. This new model will allow in vivo testing of new antimalarial compounds or their combinations against a currently circulating MDR P. falciparum strain.
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Affiliation(s)
- Nicanor Obaldía
- Malaria Drug and Vaccine Evaluation Center, Tropical Medicine Research, Panama City, Republic of Panama.
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Obaldía N. Clinico-pathological observations on the pathogenesis of severe thrombocytopenia and anemia induced by Plasmodium vivax infections during antimalarial drug efficacy trials in Aotus monkeys. Am J Trop Med Hyg 2007; 77:3-13. [PMID: 17620623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023] Open
Abstract
During routine antimalarial drug efficacy trials, we observed, for the first time, severe thrombocytopenia developing in Aotus monkeys infected with Plasmodium vivax. Data obtained from 26 Aotus infected with the AMRU-1 strain showed that 77% developed severe thrombocytopenia, whereas only 15% had severe anemia, with hemorrhagic diathesis ensuing in 31%. In general, thrombocytopenic monkeys either failed primary treatment with experimental antimalarial drugs or were found to have higher-density parasitemias, longer patency duration, and lower hematocrits. In these monkeys, severe thrombocytopenia inversely correlated to parasitemia (R = -1.0), and animals that received a blood transfusion had significantly higher platelet counts (P < 0.05) by day 38 after inoculation. In conclusion, the AMRU-1 strain of P. vivax, was considered to be highly pathogenic to Aotus monkeys, and thrombocytopenia rather than anemia should be regarded an early indicator of drug treatment failure with this strain.
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Affiliation(s)
- Nicanor Obaldía
- Malaria Drug and Vaccine Evaluation Center, Tropical Medicine Research, Panama City, Republic of Panama.
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Obaldía N. Clinico-Pathological Observations on the Pathogenesis of Severe Thrombocytopenia and Anemia Induced by Plasmodium vivax Infections During Antimalarial Drug Efficacy Trials in Aotus Monkeys. Am J Trop Med Hyg 2007. [DOI: 10.4269/ajtmh.2007.77.3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Samudio F, Santamaría AM, Obaldía N, Pascale JM, Bayard V, Calzada JE. Prevalence of Plasmodium falciparum mutations associated with antimalarial drug resistance during an epidemic in Kuna Yala, Panama, Central America. Am J Trop Med Hyg 2005; 73:839-41. [PMID: 16282290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023] Open
Abstract
A molecular epidemiology study was conducted to determine the distribution of antimalarial drug resistance alleles among field isolates of Plasmodium falciparum. Samples were obtained during an epidemic affecting Kuna Amerindians in Panama. A high prevalence of mutations associated with chloroquine, pyrimethamine, and sulfadoxine was observed. Genotype analysis of msp2 revealed a low genetic diversity of P. falciparum parasites circulating in the studied area. The public health implications of these findings for the Central American region are discussed.
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Affiliation(s)
- Franklyn Samudio
- Instituto Conmemorativo Gorgas de Estudio de la Salud, ICGES, Panama, Republic of Panama
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Affiliation(s)
- N Obaldía
- Gorgas Memorial Institute, Panamá, Republic of Panamá.
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Hirsch S, de la Maza MP, Obaldía N, Espinoza J, Hübner C, Petermann M, Bunout D. [Muscular strength: an indicator of nutritional status]. Rev Med Chil 1992; 120:615-20. [PMID: 1341789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A hand dynamometer was used to measure muscle strength in 207 patients admitted to the Gastroenterology service of a general hospital. Validation of international standards in a normal population of both sexes and different ages revealed that our normals perform at the 25% percentile of international values. Results were correlated with other measurements of nutritional status, namely anthropometric measurements, serum albumin level and tuberculin test. Compared to normals, muscle strength was significantly (p < 0.01) lower in patients with body mass index under 19, cutaneous tricipital folding < 85%, brachial circumference < 85%, and serum albumin < 3.5 g/dl. No difference in muscle strength between tuberculin positive or negative subjects was observed. None of the nutritional parameter was helpful to predict complications in patients submitted to surgery. Thus, muscle strength is a useful parameter to evaluate nutritional status but, similar to other measurements, is not predictive of surgical complications.
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Affiliation(s)
- S Hirsch
- Facultad de Medicina, Universidad de Chile, Hospital San Borja-Arriarán, Santiago de Chile
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