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Hirano M, Galarza-Muñoz G, Nagasawa C, Schott G, Wang L, Antonia AL, Jain V, Yu X, Widen SG, Briggs FBS, Gregory SG, Ko DC, Fagg WS, Bradrick S, Garcia-Blanco MA. The RNA helicase DDX39B activates FOXP3 RNA splicing to control T regulatory cell fate. eLife 2023; 12:e76927. [PMID: 37261960 PMCID: PMC10234631 DOI: 10.7554/elife.76927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 05/09/2023] [Indexed: 06/03/2023] Open
Abstract
Genes associated with increased susceptibility to multiple sclerosis (MS) have been identified, but their functions are incompletely understood. One of these genes codes for the RNA helicase DExD/H-Box Polypeptide 39B (DDX39B), which shows genetic and functional epistasis with interleukin-7 receptor-α gene (IL7R) in MS-risk. Based on evolutionary and functional arguments, we postulated that DDX39B enhances immune tolerance thereby decreasing MS risk. Consistent with such a role we show that DDX39B controls the expression of many MS susceptibility genes and important immune-related genes. Among these we identified Forkhead Box P3 (FOXP3), which codes for the master transcriptional factor in CD4+/CD25+ T regulatory cells. DDX39B knockdown led to loss of immune-regulatory and gain of immune-effector expression signatures. Splicing of FOXP3 introns, which belong to a previously unrecognized type of introns with C-rich polypyrimidine tracts, was exquisitely sensitive to DDX39B levels. Given the importance of FOXP3 in autoimmunity, this work cements DDX39B as an important guardian of immune tolerance.
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Affiliation(s)
- Minato Hirano
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- National Research Center for the Control and Prevention of Infectious Disease, Nagasaki UniversityNagasakiJapan
| | - Gaddiel Galarza-Muñoz
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- Autoimmunity Biological SolutionsGalvestonUnited States
| | - Chloe Nagasawa
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- Human Pathophysiology and Translational Medicine Program, Institute for Translational Sciences, University of Texas Medical BranchGalvestonUnited States
| | - Geraldine Schott
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
| | - Liuyang Wang
- Department of Molecular Genetics and Microbiology, Duke UniversityDurhamUnited States
| | - Alejandro L Antonia
- Department of Molecular Genetics and Microbiology, Duke UniversityDurhamUnited States
| | - Vaibhav Jain
- Duke Molecular Physiology Institute, Duke UniversityDurhamUnited States
| | - Xiaoying Yu
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- Department of Preventive Medicine and Population Health, University of Texas Medical BranchGalvestonUnited States
| | - Steven G Widen
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
| | - Farren BS Briggs
- Department of Population and Quantitative Health Sciences, School of Medicine, Case Western Reserve UniversityClevelandUnited States
| | - Simon G Gregory
- Department of Molecular Genetics and Microbiology, Duke UniversityDurhamUnited States
- Duke Molecular Physiology Institute, Duke UniversityDurhamUnited States
- Department of Neurology, Duke University School of MedicineDurhamUnited States
| | - Dennis C Ko
- Department of Molecular Genetics and Microbiology, Duke UniversityDurhamUnited States
- Division of Infectious Diseases, Department of Medicine, Duke UniversityDurhamUnited States
| | - William S Fagg
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- Transplant Division, Department of Surgery, University of Texas Medical BranchGalvestonUnited States
| | - Shelton Bradrick
- Institute of Human Infections and Immunity, University of Texas Medical BranchGalvestonUnited States
| | - Mariano A Garcia-Blanco
- Department of Biochemistry and Molecular Biology, University of Texas Medical BranchGalvestonUnited States
- Department of Internal Medicine, University of Texas Medical BranchGalvestonUnited States
- Department of Microbiology, Immunology and Cancer Biology, University of VirginiaCharlottesvilleUnited States
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Antonia AL, Barnes AB, Martin AT, Wang L, Ko DC. Variation in Leishmania chemokine suppression driven by diversification of the GP63 virulence factor. PLoS Negl Trop Dis 2021; 15:e0009224. [PMID: 34710089 PMCID: PMC8577781 DOI: 10.1371/journal.pntd.0009224] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [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: 02/10/2021] [Revised: 11/09/2021] [Accepted: 10/17/2021] [Indexed: 11/18/2022] Open
Abstract
Leishmaniasis is a neglected tropical disease with diverse outcomes ranging from self-healing lesions, to progressive non-healing lesions, to metastatic spread and destruction of mucous membranes. Although resolution of cutaneous leishmaniasis is a classic example of type-1 immunity leading to self-healing lesions, an excess of type-1 related inflammation can contribute to immunopathology and metastatic spread. Leishmania genetic diversity can contribute to variation in polarization and robustness of the immune response through differences in both pathogen sensing by the host and immune evasion by the parasite. In this study, we observed a difference in parasite chemokine suppression between the Leishmania (L.) subgenus and the Viannia (V.) subgenus, which is associated with severe immune-mediated pathology such as mucocutaneous leishmaniasis. While Leishmania (L.) subgenus parasites utilize the virulence factor and metalloprotease glycoprotein-63 (gp63) to suppress the type-1 associated host chemokine CXCL10, L. (V.) panamensis did not suppress CXCL10. To understand the molecular basis for the inter-species variation in chemokine suppression, we used in silico modeling to identify a putative CXCL10-binding site on GP63. The putative CXCL10 binding site is in a region of gp63 under significant positive selection, and it varies from the L. major wild-type sequence in all gp63 alleles identified in the L. (V.) panamensis reference genome. Mutating wild-type L. (L.) major gp63 to the L. (V.) panamensis sequence at the putative binding site impaired cleavage of CXCL10 but not a non-specific protease substrate. Notably, Viannia clinical isolates confirmed that L. (V.) panamensis primarily encodes non-CXCL10-cleaving gp63 alleles. In contrast, L. (V.) braziliensis has an intermediate level of activity, consistent with this species having more equal proportions of both alleles. Our results demonstrate how parasite genetic diversity can contribute to variation in immune responses to Leishmania spp. infection that may play critical roles in the outcome of infection. Leishmaniasis is a neglected tropical disease caused by Leishmania parasites and spread by the bites of infected sand flies. Most cases of leishmaniasis present as self-healing sores that are resolved by a balanced immune response. Other cases of leishmaniasis involve spread to sites distant from the original bite, including damage of the inner surfaces of the mouth and nose. These cases of leishmaniasis involve an excessive immune response. Leishmania parasites produce virulence factor proteins, such as GP63, to trick the immune system into mounting a weaker response. GP63 specifically degrades signaling proteins that attract and activate certain immune cells. Here, we demonstrate that Leishmania parasite species have evolved to differ in their ability to degrade signaling proteins. In Leishmania species known to cause more immune-mediated tissue damage, the GP63 virulence factor has evolved to not degrade specific immune signaling proteins, thus attracting, and activating more immune cells. Our results demonstrate how diversity among Leishmania parasite species can contribute to variation in immune responses that may play critical roles in the outcome of infection.
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Affiliation(s)
- Alejandro L. Antonia
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, North Carolina, United States of America
| | - Alyson B. Barnes
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, North Carolina, United States of America
| | - Amelia T. Martin
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, North Carolina, United States of America
| | - Liuyang Wang
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, North Carolina, United States of America
| | - Dennis C. Ko
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, North Carolina, United States of America
- Division of Infectious Diseases, Department of Medicine, School of Medicine, Duke University, Durham, North Carolina, United States of America
- * E-mail:
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Wang L, Balmat TJ, Antonia AL, Constantine FJ, Henao R, Burke TW, Ingham A, McClain MT, Tsalik EL, Ko ER, Ginsburg GS, DeLong MR, Shen X, Woods CW, Hauser ER, Ko DC. An atlas connecting shared genetic architecture of human diseases and molecular phenotypes provides insight into COVID-19 susceptibility. Genome Med 2021; 13:83. [PMID: 34001247 PMCID: PMC8127495 DOI: 10.1186/s13073-021-00904-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 05/05/2021] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND While genome-wide associations studies (GWAS) have successfully elucidated the genetic architecture of complex human traits and diseases, understanding mechanisms that lead from genetic variation to pathophysiology remains an important challenge. Methods are needed to systematically bridge this crucial gap to facilitate experimental testing of hypotheses and translation to clinical utility. RESULTS Here, we leveraged cross-phenotype associations to identify traits with shared genetic architecture, using linkage disequilibrium (LD) information to accurately capture shared SNPs by proxy, and calculate significance of enrichment. This shared genetic architecture was examined across differing biological scales through incorporating data from catalogs of clinical, cellular, and molecular GWAS. We have created an interactive web database (interactive Cross-Phenotype Analysis of GWAS database (iCPAGdb)) to facilitate exploration and allow rapid analysis of user-uploaded GWAS summary statistics. This database revealed well-known relationships among phenotypes, as well as the generation of novel hypotheses to explain the pathophysiology of common diseases. Application of iCPAGdb to a recent GWAS of severe COVID-19 demonstrated unexpected overlap of GWAS signals between COVID-19 and human diseases, including with idiopathic pulmonary fibrosis driven by the DPP9 locus. Transcriptomics from peripheral blood of COVID-19 patients demonstrated that DPP9 was induced in SARS-CoV-2 compared to healthy controls or those with bacterial infection. Further investigation of cross-phenotype SNPs associated with both severe COVID-19 and other human traits demonstrated colocalization of the GWAS signal at the ABO locus with plasma protein levels of a reported receptor of SARS-CoV-2, CD209 (DC-SIGN). This finding points to a possible mechanism whereby glycosylation of CD209 by ABO may regulate COVID-19 disease severity. CONCLUSIONS Thus, connecting genetically related traits across phenotypic scales links human diseases to molecular and cellular measurements that can reveal mechanisms and lead to novel biomarkers and therapeutic approaches. The iCPAGdb web portal is accessible at http://cpag.oit.duke.edu and the software code at https://github.com/tbalmat/iCPAGdb .
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Affiliation(s)
- Liuyang Wang
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA
| | - Thomas J Balmat
- Duke Research Computing, Duke University, Durham, NC, 27710, USA
| | - Alejandro L Antonia
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA
| | - Florica J Constantine
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC, 27710, USA
| | - Ricardo Henao
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC, 27710, USA
| | - Thomas W Burke
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC, 27710, USA
| | - Andy Ingham
- Duke Research Computing, Duke University, Durham, NC, 27710, USA
| | - Micah T McClain
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC, 27710, USA
- Durham Veterans Affairs Health Care System, Durham, NC, 27705, USA
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - Ephraim L Tsalik
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC, 27710, USA
- Durham Veterans Affairs Health Care System, Durham, NC, 27705, USA
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - Emily R Ko
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC, 27710, USA
- Department of Hospital Medicine, Duke Regional Hospital, Durham, NC, 27705, USA
| | - Geoffrey S Ginsburg
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC, 27710, USA
| | - Mark R DeLong
- Duke Research Computing, Duke University, Durham, NC, 27710, USA
| | - Xiling Shen
- Department of Biomedical Engineering, Woo Center for Big Data and Precision Health, Duke University, Durham, NC, 27710, USA
| | - Christopher W Woods
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC, 27710, USA
- Durham Veterans Affairs Health Care System, Durham, NC, 27705, USA
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - Elizabeth R Hauser
- Duke Molecular Physiology Institute and Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC, 27710, USA
- Cooperative Studies Program Epidemiology Center-Durham, Durham VA Health Care System, Durham, NC, 27705, USA
| | - Dennis C Ko
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA.
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA.
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Wang L, Balmat TJ, Antonia AL, Constantine FJ, Henao R, Burke TW, Ingham A, McClain MT, Tsalik EL, Ko ER, Ginsburg GS, DeLong MR, Shen X, Woods CW, Hauser ER, Ko DC. An atlas connecting shared genetic architecture of human diseases and molecular phenotypes provides insight into COVID-19 susceptibility. medRxiv 2020:2020.12.20.20248572. [PMID: 33398303 PMCID: PMC7781346 DOI: 10.1101/2020.12.20.20248572] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
While genome-wide associations studies (GWAS) have successfully elucidated the genetic architecture of complex human traits and diseases, understanding mechanisms that lead from genetic variation to pathophysiology remains an important challenge. Methods are needed to systematically bridge this crucial gap to facilitate experimental testing of hypotheses and translation to clinical utility. Here, we leveraged cross-phenotype associations to identify traits with shared genetic architecture, using linkage disequilibrium (LD) information to accurately capture shared SNPs by proxy, and calculate significance of enrichment. This shared genetic architecture was examined across differing biological scales through incorporating data from catalogs of clinical, cellular, and molecular GWAS. We have created an interactive web database (interactive Cross-Phenotype Analysis of GWAS database (iCPAGdb); http://cpag.oit.duke.edu) to facilitate exploration and allow rapid analysis of user-uploaded GWAS summary statistics. This database revealed well-known relationships among phenotypes, as well as the generation of novel hypotheses to explain the pathophysiology of common diseases. Application of iCPAGdb to a recent GWAS of severe COVID-19 demonstrated unexpected overlap of GWAS signals between COVID-19 and human diseases, including with idiopathic pulmonary fibrosis driven by the DPP9 locus. Transcriptomics from peripheral blood of COVID-19 patients demonstrated that DPP9 was induced in SARS-CoV-2 compared to healthy controls or those with bacterial infection. Further investigation of cross-phenotype SNPs with severe COVID-19 demonstrated colocalization of the GWAS signal of the ABO locus with plasma protein levels of a reported receptor of SARS-CoV-2, CD209 (DC-SIGN), pointing to a possible mechanism whereby glycosylation of CD209 by ABO may regulate COVID-19 disease severity. Thus, connecting genetically related traits across phenotypic scales links human diseases to molecular and cellular measurements that can reveal mechanisms and lead to novel biomarkers and therapeutic approaches.
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Affiliation(s)
- Liuyang Wang
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | | | - Alejandro L. Antonia
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Florica J. Constantine
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Ricardo Henao
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Thomas W. Burke
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Andy Ingham
- Duke Research Computing, Duke University, Durham, NC 27710, USA
| | - Micah T. McClain
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
- Durham Veterans Affairs Health Care System, Durham, NC 27705, USA
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Ephraim L. Tsalik
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
- Durham Veterans Affairs Health Care System, Durham, NC 27705, USA
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Emily R. Ko
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
- Department of Hospital Medicine, Duke Regional Hospital, Durham, NC, 27705, USA
| | - Geoffrey S. Ginsburg
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Mark R. DeLong
- Duke Research Computing, Duke University, Durham, NC 27710, USA
| | - Xiling Shen
- Department of Biomedical Engineering, Woo Center for Big Data and Precision Health, Duke University, Durham, NC 27710, USA
| | - Christopher W. Woods
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
- Durham Veterans Affairs Health Care System, Durham, NC 27705, USA
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Elizabeth R. Hauser
- Duke Molecular Physiology Institute and Department of Biostatistics and Bioinformatics, Duke University Medical Center Durham, NC 27710, USA
- Cooperative Studies Program Epidemiology Center-Durham, Durham VA Health Care System, Durham, NC 27705, USA
| | - Dennis C. Ko
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
- Lead contact
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Schott BH, Antonia AL, Wang L, Pittman KJ, Sixt BS, Barnes AB, Valdivia RH, Ko DC. Modeling of variables in cellular infection reveals CXCL10 levels are regulated by human genetic variation and the Chlamydia-encoded CPAF protease. Sci Rep 2020; 10:18269. [PMID: 33106516 PMCID: PMC7588472 DOI: 10.1038/s41598-020-75129-y] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 10/12/2020] [Indexed: 01/01/2023] Open
Abstract
Susceptibility to infectious diseases is determined by a complex interaction between host and pathogen. For infections with the obligate intracellular bacterium Chlamydia trachomatis, variation in immune activation and disease presentation are regulated by both host genetic diversity and pathogen immune evasion. Previously, we discovered a single nucleotide polymorphism (rs2869462) associated with absolute abundance of CXCL10, a pro-inflammatory T-cell chemokine. Here, we report that levels of CXCL10 change during C. trachomatis infection of cultured cells in a manner dependent on both host and pathogen. Linear modeling of cellular traits associated with CXCL10 levels identified a strong, negative correlation with bacterial burden, suggesting that C. trachomatis actively suppresses CXCL10. We identified the pathogen-encoded factor responsible for this suppression as the chlamydial protease- or proteasome-like activity factor, CPAF. Further, we applied our modeling approach to other host cytokines in response to C. trachomatis and found evidence that RANTES, another T-cell chemoattractant, is actively suppressed by Chlamydia. However, this observed suppression of RANTES is not mediated by CPAF. Overall, our results demonstrate that CPAF suppresses CXCL10 to evade the host cytokine response and that modeling of cellular infection parameters can reveal previously unrecognized facets of host-pathogen interactions.
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Affiliation(s)
- Benjamin H Schott
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA
- Duke University Program in Genetics and Genomics, Duke University, Durham, NC, 27710, USA
| | - Alejandro L Antonia
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA
| | - Liuyang Wang
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA
| | - Kelly J Pittman
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA
| | - Barbara S Sixt
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA
- Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research, Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Alyson B Barnes
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA
| | - Raphael H Valdivia
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA
| | - Dennis C Ko
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, 0049 CARL Building Box 3053, 213 Research Drive, Durham, NC, 27710, USA.
- Duke University Program in Genetics and Genomics, Duke University, Durham, NC, 27710, USA.
- Division of Infectious Diseases, Department of Medicine, School of Medicine, Duke University, Durham, NC, 27710, USA.
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Antonia AL, Ko DC. Leishmaniasis: A spectrum of diseases shaped by evolutionary pressures across diverse life cycle. Evol Med Public Health 2020; 2020:139-140. [PMID: 32983539 PMCID: PMC7502267 DOI: 10.1093/emph/eoaa032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 08/18/2020] [Indexed: 01/09/2023] Open
Affiliation(s)
- Alejandro L Antonia
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Dennis C Ko
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
- Division of Infectious Diseases, Department of Medicine, School of Medicine, Duke University, Durham, NC 27710, USA
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Antonia AL, Gibbs KD, Trahair ED, Pittman KJ, Martin AT, Schott BH, Smith JS, Rajagopal S, Thompson JW, Reinhardt RL, Ko DC. Pathogen Evasion of Chemokine Response Through Suppression of CXCL10. Front Cell Infect Microbiol 2019; 9:280. [PMID: 31440475 PMCID: PMC6693555 DOI: 10.3389/fcimb.2019.00280] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 07/23/2019] [Indexed: 01/10/2023] Open
Abstract
Clearance of intracellular pathogens, such as Leishmania (L.) major, depends on an immune response with well-regulated cytokine signaling. Here we describe a pathogen-mediated mechanism of evading CXCL10, a chemokine with diverse antimicrobial functions, including T cell recruitment. Infection with L. major in a human monocyte cell line induced robust CXCL10 transcription without increasing extracellular CXCL10 protein concentrations. We found that this transcriptionally independent suppression of CXCL10 is mediated by the virulence factor and protease, glycoprotein-63 (gp63). Specifically, GP63 cleaves CXCL10 after amino acid A81 at the base of a C-terminal alpha-helix. Cytokine cleavage by GP63 demonstrated specificity, as GP63 cleaved CXCL10 and its homologs, which all bind the CXCR3 receptor, but not distantly related chemokines, such as CXCL8 and CCL22. Further characterization demonstrated that CXCL10 cleavage activity by GP63 was produced by both extracellular promastigotes and intracellular amastigotes. Crucially, CXCL10 cleavage impaired T cell chemotaxis in vitro, indicating that cleaved CXCL10 cannot signal through CXCR3. Ultimately, we propose CXCL10 suppression is a convergent mechanism of immune evasion, as Salmonella enterica and Chlamydia trachomatis also suppress CXCL10. This commonality suggests that counteracting CXCL10 suppression may provide a generalizable therapeutic strategy against intracellular pathogens. Importance Leishmaniasis, an infectious disease that annually affects over one million people, is caused by intracellular parasites that have evolved to evade the host's attempts to eliminate the parasite. Cutaneous leishmaniasis results in disfiguring skin lesions if the host immune system does not appropriately respond to infection. A family of molecules called chemokines coordinate recruitment of the immune cells required to eliminate infection. Here, we demonstrate a novel mechanism that Leishmania (L.) spp. employ to suppress host chemokines: a Leishmania-encoded protease cleaves chemokines known to recruit T cells that fight off infection. We observe that other common human intracellular pathogens, including Chlamydia trachomatis and Salmonella enterica, reduce levels of the same chemokines, suggesting a strong selective pressure to avoid this component of the immune response. Our study provides new insights into how intracellular pathogens interact with the host immune response to enhance pathogen survival.
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Affiliation(s)
- Alejandro L. Antonia
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, United States
| | - Kyle D. Gibbs
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, United States
| | - Esme D. Trahair
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, United States
| | - Kelly J. Pittman
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, United States
| | - Amelia T. Martin
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, United States
| | - Benjamin H. Schott
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, United States
| | - Jeffrey S. Smith
- Department of Biochemistry, School of Medicine, Duke University, Durham, NC, United States
| | - Sudarshan Rajagopal
- Department of Biochemistry, School of Medicine, Duke University, Durham, NC, United States
- Division of Cardiology, Department of Medicine, School of Medicine, Duke University, Durham, NC, United States
| | - J. Will Thompson
- Proteomics and Metabolomics Shared Resource, Center for Genomics and Computational Biology, School of Medicine, Duke University, Durham, NC, United States
| | - Richard Lee Reinhardt
- Department of Biomedical Research, National Jewish Health, Denver, CO, United States
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
| | - Dennis C. Ko
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC, United States
- Division of Infectious Diseases, Department of Medicine, School of Medicine, Duke University, Durham, NC, United States
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Antonia AL, Wang L, Ko DC. A real-time PCR assay for quantification of parasite burden in murine models of leishmaniasis. PeerJ 2018; 6:e5905. [PMID: 30430041 PMCID: PMC6231426 DOI: 10.7717/peerj.5905] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 10/09/2018] [Indexed: 12/22/2022] Open
Abstract
Eukaryotic parasites in the genus Leishmania place approximately 350 million people per year at risk of disease. In addition to their global health significance, Leishmania spp. have served as an important model for delineating basic concepts in immunology such as T-helper cell polarization. There have been many qPCR-based assays reported for measuring parasite burden in humans and animals. However, these are largely optimized for use in clinical diagnosis and not specifically for animal models. This has led several of these assays to have suboptimal characteristics for use in animal models. For example, multi-copy number genes have been frequently used to increase sensitivity but are subject to greater plasticity within the genome and thus may confound effects of experimental manipulations in animal models. In this study, we developed a sybr-green based quantitative touchdown PCR assay for a highly conserved and single-copy putative RNA-binding protein, DRBD3. With primers that share greater than 90% sequence identity across all sequenced Leishmania spp., we demonstrate that this assay has a lower limit of detection of 100 fg of parasite DNA for Leishmania major, L. donovani, L. venezuelensis, and L. panamensis. Using C57BL6/J mice, we used this assay to monitor parasite burden over 1 month of infection with two strains of L. major (Seidman and Friedlin), and L. venezeuelensis. These characteristics rival the sensitivity of previously reported qPCR based methods of parasite quantitation while amplifying a stable, single copy gene. Use of this protocol in the future will lead to improved accuracy in animal based models and help to tease apart differences in biology of host-parasite interactions.
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Affiliation(s)
- Alejandro L. Antonia
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
| | - Liuyang Wang
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
| | - Dennis C. Ko
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
- Division of Infectious Diseases, Department of Medicine, Duke University, Durham, NC, USA
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Wang L, Pittman KJ, Barker JR, Salinas RE, Stanaway IB, Williams GD, Carroll RJ, Balmat T, Ingham A, Gopalakrishnan AM, Gibbs KD, Antonia AL, Heitman J, Lee SC, Jarvik GP, Denny JC, Horner SM, DeLong MR, Valdivia RH, Crosslin DR, Ko DC. An Atlas of Genetic Variation Linking Pathogen-Induced Cellular Traits to Human Disease. Cell Host Microbe 2018; 24:308-323.e6. [PMID: 30092202 PMCID: PMC6093297 DOI: 10.1016/j.chom.2018.07.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/28/2018] [Accepted: 07/05/2018] [Indexed: 12/18/2022]
Abstract
Pathogens have been a strong driving force for natural selection. Therefore, understanding how human genetic differences impact infection-related cellular traits can mechanistically link genetic variation to disease susceptibility. Here we report the Hi-HOST Phenome Project (H2P2): a catalog of cellular genome-wide association studies (GWAS) comprising 79 infection-related phenotypes in response to 8 pathogens in 528 lymphoblastoid cell lines. Seventeen loci surpass genome-wide significance for infection-associated phenotypes ranging from pathogen replication to cytokine production. We combined H2P2 with clinical association data from patients to identify a SNP near CXCL10 as a risk factor for inflammatory bowel disease. A SNP in the transcriptional repressor ZBTB20 demonstrated pleiotropy, likely through suppression of multiple target genes, and was associated with viral hepatitis. These data are available on a web portal to facilitate interpreting human genome variation through the lens of cell biology and should serve as a rich resource for the research community.
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Affiliation(s)
- Liuyang Wang
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Kelly J Pittman
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Jeffrey R Barker
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Raul E Salinas
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Ian B Stanaway
- Department of Biomedical Informatics and Medical Education, School of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Graham D Williams
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Robert J Carroll
- Department of Biomedical Informatics, School of Medicine, Vanderbilt University, Nashville, TN 37212, USA
| | - Tom Balmat
- Social Science Research Institute, Duke University, Durham, NC 27710, USA
| | - Andy Ingham
- Duke Research Computing, Duke University, Durham, NC 27710, USA
| | - Anusha M Gopalakrishnan
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Kyle D Gibbs
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Alejandro L Antonia
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA; Division of Infectious Diseases, Department of Medicine, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Soo Chan Lee
- South Texas Center for Emerging Infectious Diseases (STCEID), Department of Biology, College of Sciences, the University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Gail P Jarvik
- Department of Medicine, Division of Medical Genetics, School of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Joshua C Denny
- Department of Biomedical Informatics, School of Medicine, Vanderbilt University, Nashville, TN 37212, USA
| | - Stacy M Horner
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA; Division of Infectious Diseases, Department of Medicine, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Mark R DeLong
- Duke Research Computing, Duke University, Durham, NC 27710, USA
| | - Raphael H Valdivia
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA
| | - David R Crosslin
- Department of Biomedical Informatics and Medical Education, School of Medicine, University of Washington, Seattle, WA 98195, USA
| | - Dennis C Ko
- Department of Molecular Genetics and Microbiology, School of Medicine, Duke University, Durham, NC 27710, USA; Division of Infectious Diseases, Department of Medicine, School of Medicine, Duke University, Durham, NC 27710, USA.
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Taylor SM, Antonia AL, Harrington WE, Goheen MM, Mwapasa V, Chaluluka E, Fried M, Kabyemela E, Madanitsa M, Khairallah C, Kalilani-Phiri L, Tshefu AK, Rogerson SJ, Ter Kuile FO, Duffy PE, Meshnick SR. Independent lineages of highly sulfadoxine-resistant Plasmodium falciparum haplotypes, eastern Africa. Emerg Infect Dis 2015; 20:1140-8. [PMID: 24960247 PMCID: PMC4073871 DOI: 10.3201/eid2007.131720] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Parasites with increased resistance to sulfadoxine might undermine malaria control measures. Sulfadoxine-resistant Plasmodium falciparum undermines malaria prevention with sulfadoxine/pyrimethamine. Parasites with a highly resistant mutant dihydropteroate synthase (dhps) haplotype have recently emerged in eastern Africa; they negated preventive benefits of sulfadoxine/pyrimethamine, and might exacerbate placental malaria. We explored emerging lineages of dhps mutant haplotypes in Malawi, the Democratic Republic of the Congo, and Tanzania by using analyses of genetic microsatellites flanking the dhps locus. In Malawi, a triple-mutant dhps SGEG (mutant amino acids are underlined) haplotype emerged in 2010 that was closely related to pre-existing double-mutant SGEA haplotypes, suggesting local origination in Malawi. When we compared mutant strains with parasites from the Democratic Republic of the Congo and Tanzania by multiple independent analyses, we found that SGEG parasites were partitioned into separate lineages by country. These findings support a model of local origination of SGEGdhps haplotypes, rather than geographic diffusion, and have implications for investigations of emergence and effects of parasite drug resistance.
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Antonia AL, Taylor SM, Janko M, Emch M, Tshefu AK, Meshnick SR. A cross-sectional survey of Plasmodium falciparum pfcrt mutant haplotypes in the Democratic Republic of Congo. Am J Trop Med Hyg 2014; 90:1094-7. [PMID: 24732459 DOI: 10.4269/ajtmh.13-0378] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In the Democratic Republic of the Congo (DRC), artesunate-amodiaquine is first-line therapy for falciparum malaria; little is known about the prevalence of molecular markers of parasite drug resistance. Across the DRC, we genotyped 166 parasites in Plasmodium falciparum chloroquine resistance transporter (pfcrt) using polymerase chain reaction (PCR) and sequencing. Of these parasites, 73 (44%) parasites were pure wild-type CVMNK, 55 (31%) parasites were chloroquine-resistant CVIET: , 35 (21.1%) parasites were mixed CVMNK and CVIET: , and 3 parasites were other genotypes. Ninety-two infections (55.4%) harbored the pfcrt K76T: substitution that is highly correlated with chloroquine failure. The amodiaquine-resistant S: VMNT: haplotype was absent. Geographically, pfcrt haplotypes were not clearly clustered. Chloroquine accounted for 19.4% of antimalarial use, and amodiaquine accounted for 15.3% of antimalarial use; there were no associations between drug use and mutant haplotype prevalence. In the DRC, our molecular survey indicates that resistance to chloroquine is substantial but that resistance to amodiaquine is absent. These contrasting findings highlight the need for molecular surveillance of drug resistance to inform malaria control policies.
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Affiliation(s)
- Alejandro L Antonia
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina; Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, North Carolina; Department of Geography, University of North Carolina, Chapel Hill, North Carolina; Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina; Ecole de Sante Publique, Faculte de Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Steve M Taylor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina; Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, North Carolina; Department of Geography, University of North Carolina, Chapel Hill, North Carolina; Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina; Ecole de Sante Publique, Faculte de Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Mark Janko
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina; Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, North Carolina; Department of Geography, University of North Carolina, Chapel Hill, North Carolina; Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina; Ecole de Sante Publique, Faculte de Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Michael Emch
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina; Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, North Carolina; Department of Geography, University of North Carolina, Chapel Hill, North Carolina; Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina; Ecole de Sante Publique, Faculte de Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Antoinette K Tshefu
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina; Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, North Carolina; Department of Geography, University of North Carolina, Chapel Hill, North Carolina; Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina; Ecole de Sante Publique, Faculte de Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina; Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, North Carolina; Department of Geography, University of North Carolina, Chapel Hill, North Carolina; Carolina Population Center, University of North Carolina, Chapel Hill, North Carolina; Ecole de Sante Publique, Faculte de Medicine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
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Taylor SM, Antonia AL, Parobek CM, Juliano JJ, Janko M, Emch M, Alam MT, Udhayakumar V, Tshefu AK, Meshnick SR. Plasmodium falciparum sulfadoxine resistance is geographically and genetically clustered within the DR Congo. Sci Rep 2013; 3:1165. [PMID: 23372922 PMCID: PMC3558697 DOI: 10.1038/srep01165] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [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: 11/06/2012] [Accepted: 12/13/2012] [Indexed: 11/10/2022] Open
Abstract
Understanding the spatial clustering of Plasmodium falciparum populations can assist efforts to contain drug-resistant parasites and maintain the efficacy of future drugs. We sequenced single nucleotide polymorphisms (SNPs) in the dihydropteroate synthase gene (dhps) associated with sulfadoxine resistance and 5 microsatellite loci flanking dhps in order to investigate the genetic backgrounds, genetic relatedness, and geographic clustering of falciparum parasites in the Democratic Republic of the Congo (DRC). Resistant haplotypes were clustered into subpopulations: one in the northeast DRC, and the other in the balance of the DRC. Network and clonal lineage analyses of the flanking microsatellites indicate that geographically-distinct mutant dhps haplotypes derive from separate lineages. The DRC is therefore a watershed for haplotypes associated with sulfadoxine resistance. Given the importance of central Africa as a corridor for the spread of antimalarial resistance, the identification of the mechanisms of this transit can inform future policies to contain drug-resistant parasite strains.
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Affiliation(s)
- Steve M Taylor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina , Chapel Hill, USA.
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Taylor SM, Antonia AL, Chaluluka E, Mwapasa V, Feng G, Molyneux ME, ter Kuile FO, Meshnick SR, Rogerson SJ. Antenatal receipt of sulfadoxine-pyrimethamine does not exacerbate pregnancy-associated malaria despite the expansion of drug-resistant Plasmodium falciparum: clinical outcomes from the QuEERPAM study. Clin Infect Dis 2012; 55:42-50. [PMID: 22441649 DOI: 10.1093/cid/cis301] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Antenatal intermittent preventive therapy with 2 doses of sulfadoxine-pyrimethamine (IPTp-SP) is the mainstay of efforts in sub-Saharan Africa to prevent pregnancy-associated malaria (PAM). Recent studies report that drug resistance may cause IPTp-SP to exacerbate PAM morbidity, raising fears that current policies will cause harm as resistance spreads. METHODS We conducted a serial, cross-sectional analysis of the relationships between IPTp-SP receipt, SP-resistant Plasmodium falciparum, and PAM morbidity in delivering women during a period of 9 years at a single site in Malawi. PAM morbidity was assessed by parasite densities, placental histology, and birth outcomes. RESULTS The prevalence of parasites with highly SP-resistant haplotypes increased from 17% to 100% (P < .001), and the proportion of women receiving full IPTp (≥2 doses) increased from 25% to 82% (P < .001). Women who received full IPTp with SP had lower peripheral (P = .018) and placental (P < .001) parasite densities than women who received suboptimal IPTp (<2 doses). This effect was not significantly modified by the presence of highly SP-resistant haplotypes. After adjustment for covariates, the receipt of SP in the presence of SP-resistant P. falciparum did not exacerbate any parasitologic, histologic, or clinical measures of PAM morbidity. CONCLUSIONS In this longitudinal study of malaria at delivery, the receipt of SP as IPTp did not potentiate PAM morbidity despite the increasing prevalence and fixation of SP-resistant P. falciparum haplotypes. Even when there is substantial resistance, SP may be used in modified IPTp regimens as a component of comprehensive antenatal care.
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Affiliation(s)
- Steve M Taylor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, 27599, USA.
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