1
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Bucşan AN, Veatch A, Singh DK, Akter S, Golden NA, Kirkpatrick M, Threeton B, Moodley C, Ahmed M, Doyle LA, Russell-Lodrigue K, Norton EB, Didier PJ, Roy CJ, Abramovitch RB, Mehra S, Khader SA, Kaushal D. Response to Hypoxia and the Ensuing Dysregulation of Inflammation Impacts Mycobacterium tuberculosis Pathogenicity. Am J Respir Crit Care Med 2022; 206:94-104. [PMID: 35412961 PMCID: PMC9718519 DOI: 10.1164/rccm.202112-2747oc] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Rationale: Different Mycobacterium tuberculosis (Mtb) strains exhibit variable degrees of virulence in humans and animal models. Differing stress response strategies used by different strains of Mtb could influence virulence. Objectives: We compared the virulence of two strains of Mtb with use in animal model research: CDC1551 and Erdman. Methods: Rhesus macaques, which develop human-like tuberculosis attributes and pathology, were infected with a high dose of either strain via aerosol, and virulence was compared by bacterial burden and pathology. Measurements and Main Results: Infection with Erdman resulted in significantly shorter times to euthanasia and higher bacterial burdens and greater systemic inflammation and lung pathology relative to those infected with CDC1551. Macaques infected with Erdman also exhibited significantly higher early inflammatory myeloid cell influx to the lung, greater macrophage and T cell activity, and higher expression of lung remodeling (extracellular matrix) genes, consistent with greater pathology. Expression of NOTCH4 (neurogenic locus notch homolog 4) signaling, which is induced in response to hypoxia and promotes undifferentiated cellular state, was also higher in Erdman-infected lungs. The granulomas generated by Erdman, and not CDC1551, infection appeared to have larger regions of necrosis, which is strongly associated with hypoxia. To better understand the mechanisms of differential hypoxia induction by these strains, we subjected both to hypoxia in vitro. Erdman induced higher concentrations of DosR regulon relative to CDC1551. The DosR regulon is the global regulator of response to hypoxia in Mtb and critical for its persistence in granulomas. Conclusions: Our results show that the response to hypoxia is a critical mediator of virulence determination in Mtb, with potential impacts on bacillary persistence, reactivation, and efficiency of therapeutics.
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Affiliation(s)
- Allison N. Bucşan
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana
| | - Ashley Veatch
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana
| | - Dhiraj K. Singh
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas
| | - Sadia Akter
- Department of Molecular Microbiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri
| | - Nadia A. Golden
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana
| | - Melanie Kirkpatrick
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana
| | - Breanna Threeton
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana
| | - Chivonne Moodley
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana
| | - Mushtaq Ahmed
- Department of Molecular Microbiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri
| | - Lara A. Doyle
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana
| | - Kasi Russell-Lodrigue
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana
| | - Elizabeth B. Norton
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana; and
| | - Peter J. Didier
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana
| | - Chad J. Roy
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana;,Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas
| | - Robert B. Abramovitch
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan
| | - Smriti Mehra
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana;,Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas
| | - Shabaana A. Khader
- Department of Molecular Microbiology, Washington University in St. Louis School of Medicine, St. Louis, Missouri
| | - Deepak Kaushal
- Tulane National Primate Research Center, Tulane University Health Sciences Center, Covington, Louisiana;,Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas
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2
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Gough M, Singh DK, Moodley C, Niu T, Golden NA, Kaushal D, Mehra S. Peripheral Blood Markers Correlate with the Progression of Active Tuberculosis Relative to Latent Control of Mycobacterium tuberculosis Infection in Macaques. Pathogens 2022; 11:pathogens11050544. [PMID: 35631065 PMCID: PMC9146669 DOI: 10.3390/pathogens11050544] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/23/2022] [Accepted: 04/26/2022] [Indexed: 01/08/2023] Open
Abstract
Despite a century of research into tuberculosis (TB), there is a dearth of reproducible, easily quantifiable, biomarkers that can predict disease onset and differentiate between host disease states. Due to the challenges associated with human sampling, nonhuman primates (NHPs) are utilized for recapitulating the closest possible modelling of human TB. To establish a predictive peripheral biomarker profile based on a larger cohort of rhesus macaques (RM), we analyzed results pertaining to peripheral blood serum chemistry and cell counts from RMs that were experimentally exposed to Mtb in our prior studies and characterized as having either developed active TB (ATB) disease or latent TB infection (LTBI). We compared lung CFU burdens and quantitative pathologies with a number of measurables in the peripheral blood. Based on our results, the investigations were then extended to the study of specific molecules and cells in the lung compartments of a subset of these animals and their immune responses. In addition to the elevated serum C-reactive protein (CRP) levels, frequently used to discern the level of Mtb infection in model systems, reduced serum albumin-to-globulin (A/G) ratios were also predictive of active TB disease. Furthermore, higher peripheral myeloid cell levels, particularly those of neutrophils, kynurenine-to-tryptophan ratio, an indicator of induced expression of the immunosuppressive molecule indoleamine dioxygenase, and an influx of myeloid cell populations could also efficiently discriminate between ATB and LTBI in experimentally infected macaques. These quantifiable correlates of disease were then used in conjunction with a regression-based analysis to predict bacterial load. Our results suggest a potential biomarker profile of TB disease in rhesus macaques, that could inform future NHP–TB research. Our results thus suggest that specific biomarkers may be developed from the myeloid subset of peripheral blood or plasma with the ability to discriminate between active and latent Mtb infection.
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Affiliation(s)
- Maya Gough
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (M.G.); (D.K.S.); (C.M.)
| | - Dhiraj K. Singh
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (M.G.); (D.K.S.); (C.M.)
| | - Chivonne Moodley
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (M.G.); (D.K.S.); (C.M.)
- Tulane University Health Science Center, New Orleans, LA 70112, USA
| | - Tianhua Niu
- Department of Biostatistics and Bioinformatics, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA 70112, USA;
| | - Nadia A. Golden
- Tulane National Primate Research Center, Covington, LA 70433, USA;
| | - Deepak Kaushal
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (M.G.); (D.K.S.); (C.M.)
- Correspondence: (D.K); (S.M.); Tel.: +210-258-9209 (D.K.); +210-258-9508 (S.M.)
| | - Smriti Mehra
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX 78227, USA; (M.G.); (D.K.S.); (C.M.)
- Correspondence: (D.K); (S.M.); Tel.: +210-258-9209 (D.K.); +210-258-9508 (S.M.)
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3
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Han K, Blair RV, Iwanaga N, Liu F, Russell-Lodrigue KE, Qin Z, Midkiff CC, Golden NA, Doyle-Meyers LA, Kabir ME, Chandler KE, Cutrera KL, Ren M, Monjure CJ, Lehmicke G, Fischer T, Beddingfield B, Wanek AG, Birnbaum A, Maness NJ, Roy CJ, Datta PK, Rappaport J, Kolls JK, Qin X. Lung Expression of Human Angiotensin-Converting Enzyme 2 Sensitizes the Mouse to SARS-CoV-2 Infection. Am J Respir Cell Mol Biol 2021; 64:79-88. [PMID: 32991819 PMCID: PMC7781002 DOI: 10.1165/rcmb.2020-0354oc] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [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: 08/10/2020] [Accepted: 09/21/2020] [Indexed: 12/11/2022] Open
Abstract
Preclinical mouse models that recapitulate some characteristics of coronavirus disease (COVID-19) will facilitate focused study of pathogenesis and virus-host responses. Human agniotensin-converting enzyme 2 (hACE2) serves as an entry receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to infect people via binding to envelope spike proteins. Herein we report development and characterization of a rapidly deployable COVID-19 mouse model. C57BL/6J (B6) mice expressing hACE2 in the lung were transduced by oropharyngeal delivery of the recombinant human adenovirus type 5 that expresses hACE2 (Ad5-hACE2). Mice were infected with SARS-CoV-2 at Day 4 after transduction and developed interstitial pneumonia associated with perivascular inflammation, accompanied by significantly higher viral load in lungs at Days 3, 6, and 12 after infection compared with Ad5-empty control group. SARS-CoV-2 was detected in pneumocytes in alveolar septa. Transcriptomic analysis of lungs demonstrated that the infected Ad5-hACE mice had a significant increase in IFN-dependent chemokines Cxcl9 and Cxcl10, and genes associated with effector T-cell populations including Cd3 g, Cd8a, and Gzmb. Pathway analysis showed that several Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were enriched in the data set, including cytokine-cytokine receptor interaction, the chemokine signaling pathway, the NOD-like receptor signaling pathway, the measles pathway, and the IL-17 signaling pathway. This response is correlative to clinical response in lungs of patients with COVID-19. These results demonstrate that expression of hACE2 via adenovirus delivery system sensitized the mouse to SARS-CoV-2 infection and resulted in the development of a mild COVID-19 phenotype, highlighting the immune and inflammatory host responses to SARS-CoV-2 infection. This rapidly deployable COVID-19 mouse model is useful for preclinical and pathogenesis studies of COVID-19.
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Affiliation(s)
- Kun Han
- Tulane National Primate Research Center, Covington, Louisiana; and
| | - Robert V. Blair
- Tulane National Primate Research Center, Covington, Louisiana; and
| | - Naoki Iwanaga
- Department of Medicine and Department of Pediatrics, Center for Translational Research in Infection and Inflammation, and
| | - Fengming Liu
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
| | | | - Zhongnan Qin
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
| | | | - Nadia A. Golden
- Tulane National Primate Research Center, Covington, Louisiana; and
| | | | - Mohammad E. Kabir
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
| | | | | | - Mi Ren
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
| | | | - Gabrielle Lehmicke
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Tracy Fischer
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
| | | | - Alanna G. Wanek
- Department of Medicine and Department of Pediatrics, Center for Translational Research in Infection and Inflammation, and
| | - Angela Birnbaum
- Tulane National Primate Research Center, Covington, Louisiana; and
| | - Nicholas J. Maness
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Chad J. Roy
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Prasun K. Datta
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Jay Rappaport
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
| | - Jay K. Kolls
- Department of Medicine and Department of Pediatrics, Center for Translational Research in Infection and Inflammation, and
| | - Xuebin Qin
- Tulane National Primate Research Center, Covington, Louisiana; and
- Department of Immunology and Microbiology, Tulane University School of Medicine, New Orleans, Louisiana
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4
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Coskun FS, Srivastava S, Raj P, Dozmorov I, Belkaya S, Mehra S, Golden NA, Bucsan AN, Chapagain ML, Wakeland EK, Kaushal D, Gumbo T, van Oers NSC. sncRNA-1 Is a Small Noncoding RNA Produced by Mycobacterium tuberculosis in Infected Cells That Positively Regulates Genes Coupled to Oleic Acid Biosynthesis. Front Microbiol 2020; 11:1631. [PMID: 32849337 PMCID: PMC7399025 DOI: 10.3389/fmicb.2020.01631] [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: 05/01/2020] [Accepted: 06/23/2020] [Indexed: 12/21/2022] Open
Abstract
Nearly one third of the world’s population is infected with Mycobacterium tuberculosis (Mtb). While much work has focused on the role of different Mtb encoded proteins in pathogenesis, recent studies have revealed that Mtb also transcribes many noncoding RNAs whose functions remain poorly characterized. We performed RNA sequencing and identified a subset of Mtb H37Rv-encoded small RNAs (<30 nts in length) that were produced in infected macrophages. Designated as smaller noncoding RNAs (sncRNAs), three of these predominated the read counts. Each of the three, sncRNA-1, sncRNA-6, and sncRNA-8 had surrounding sequences with predicted stable secondary RNA stem loops. Site-directed mutagenesis of the precursor sequences suggest the existence of a hairpin loop dependent RNA processing mechanism. A functional assessment of sncRNA-1 suggested that it positively regulated two mycobacterial transcripts involved in oleic acid biosynthesis. Complementary loss- and gain- of-function approaches revealed that sncRNA-1 positively supports Mtb growth and survival in nutrient-depleted cultures as well as in infected macrophages. Overall, the findings reveal that Mtb produces sncRNAs in infected cells, with sncRNA-1 modulating mycobacterial gene expression including genes coupled to oleic acid biogenesis.
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Affiliation(s)
- Fatma S Coskun
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Shashikant Srivastava
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, United States
| | - Prithvi Raj
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Igor Dozmorov
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Serkan Belkaya
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Smriti Mehra
- Tulane National Primate Research Center, School of Medicine, Tulane University, Covington, LA, United States
| | - Nadia A Golden
- Tulane National Primate Research Center, School of Medicine, Tulane University, Covington, LA, United States
| | - Allison N Bucsan
- Tulane National Primate Research Center, School of Medicine, Tulane University, Covington, LA, United States
| | - Moti L Chapagain
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, United States
| | - Edward K Wakeland
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Deepak Kaushal
- Tulane National Primate Research Center, School of Medicine, Tulane University, Covington, LA, United States.,Texas Biomedical Research Institute, San Antonio, TX, United States
| | - Tawanda Gumbo
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, United States
| | - Nicolai S C van Oers
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, United States.,Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, TX, United States.,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, United States
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5
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Phillips BL, Gautam US, Bucsan AN, Foreman TW, Golden NA, Niu T, Kaushal D, Mehra S. LAG-3 potentiates the survival of Mycobacterium tuberculosis in host phagocytes by modulating mitochondrial signaling in an in-vitro granuloma model. PLoS One 2017; 12:e0180413. [PMID: 28880895 PMCID: PMC5589099 DOI: 10.1371/journal.pone.0180413] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [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: 04/12/2017] [Accepted: 05/28/2017] [Indexed: 11/23/2022] Open
Abstract
CD4+ T-cell mediated Th1 immune responses are critical for immunity to TB. The immunomodulatory protein, lymphocyte activation gene-3 (LAG-3) decreases Th1-type immune responses in T-cells. LAG-3 expression is significantly induced in the lungs of macaques with active TB and correlates with increased bacterial burden. Overproduction of LAG-3 can greatly diminish responses and could lead to uncontrolled Mtb replication. To assess the effect of LAG-3 on the progression of Mtb infection, we developed a co-culture system wherein blood-derived macrophages are infected with Mtb and supplemented with macaque blood or lung derived CD4+ T-cells. Silencing LAG-3 signaling in macaque lung CD4+ T-cells enhanced killing of Mtb in co-cultures, accompanied by reduced mitochondrial electron transport and increased IFN-γ expression. Thus, LAG-3 may modulate adaptive immunity to Mtb infection by interfering with the mitochondrial apoptosis pathway. Better understanding this pathway could allow us to circumvent immune features that promote disease.
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Affiliation(s)
- Bonnie L Phillips
- Tulane National Primate Research Center, Covington, Louisiana, United States of America.,Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Uma S Gautam
- Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Allison N Bucsan
- Tulane National Primate Research Center, Covington, Louisiana, United States of America.,Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Taylor W Foreman
- Tulane National Primate Research Center, Covington, Louisiana, United States of America.,Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Nadia A Golden
- Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Tianhua Niu
- Department of Biostatistics and Bioinformatics, Tulane University School of Public Health, New Orleans, Louisiana, United States of America
| | - Deepak Kaushal
- Tulane National Primate Research Center, Covington, Louisiana, United States of America.,Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Smriti Mehra
- Tulane National Primate Research Center, Covington, Louisiana, United States of America.,Department of Pathobiological Sciences, Louisiana State University School of Veterinary Medicine, Baton Rouge, Louisiana, United States of America
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6
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Hudock TA, Foreman TW, Bandyopadhyay N, Gautam US, Veatch AV, LoBato DN, Gentry KM, Golden NA, Cavigli A, Mueller M, Hwang SA, Hunter RL, Alvarez X, Lackner AA, Bader JS, Mehra S, Kaushal D. Hypoxia Sensing and Persistence Genes Are Expressed during the Intragranulomatous Survival of Mycobacterium tuberculosis. Am J Respir Cell Mol Biol 2017; 56:637-647. [PMID: 28135421 DOI: 10.1165/rcmb.2016-0239oc] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Although it is accepted that the environment within the granuloma profoundly affects Mycobacterium tuberculosis (Mtb) and infection outcome, our ability to understand Mtb gene expression in these niches has been limited. We determined intragranulomatous gene expression in human-like lung lesions derived from nonhuman primates with both active tuberculosis (ATB) and latent TB infection (LTBI). We employed a non-laser-based approach to microdissect individual lung lesions and interrogate the global transcriptome of Mtb within granulomas. Mtb genes expressed in classical granulomas with central, caseous necrosis, as well as within the caseum itself, were identified and compared with other Mtb lesions in animals with ATB (n = 7) or LTBI (n = 7). Results were validated using both an oligonucleotide approach and RT-PCR on macaque samples and by using human TB samples. We detected approximately 2,900 and 1,850 statistically significant genes in ATB and LTBI lesions, respectively (linear models for microarray analysis, Bonferroni corrected, P < 0.05). Of these genes, the expression of approximately 1,300 (ATB) and 900 (LTBI) was positively induced. We identified the induction of key regulons and compared our results to genes previously determined to be required for Mtb growth. Our results indicate pathways that Mtb uses to ensure its survival in a highly stressful environment in vivo. A large number of genes is commonly expressed in granulomas with ATB and LTBI. In addition, the enhanced expression of the dormancy survival regulon was a key feature of lesions in animals with LTBI, stressing its importance in the persistence of Mtb during the chronic phase of infection.
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Affiliation(s)
- Teresa A Hudock
- 1 Tulane National Primate Research Center, Covington, Louisiana.,2 Tulane University Health Sciences, New Orleans, Louisiana; and
| | - Taylor W Foreman
- 1 Tulane National Primate Research Center, Covington, Louisiana.,2 Tulane University Health Sciences, New Orleans, Louisiana; and
| | - Nirmalya Bandyopadhyay
- 3 Whitaker Biomedical Engineering Institute, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Uma S Gautam
- 1 Tulane National Primate Research Center, Covington, Louisiana
| | - Ashley V Veatch
- 1 Tulane National Primate Research Center, Covington, Louisiana.,2 Tulane University Health Sciences, New Orleans, Louisiana; and
| | - Denae N LoBato
- 1 Tulane National Primate Research Center, Covington, Louisiana
| | - Kaylee M Gentry
- 1 Tulane National Primate Research Center, Covington, Louisiana
| | - Nadia A Golden
- 1 Tulane National Primate Research Center, Covington, Louisiana
| | - Amy Cavigli
- 1 Tulane National Primate Research Center, Covington, Louisiana
| | | | - Shen-An Hwang
- 4 Department of Pathology and Laboratory Medicine, University of Texas Health Science Center, Houston, Texas
| | - Robert L Hunter
- 4 Department of Pathology and Laboratory Medicine, University of Texas Health Science Center, Houston, Texas
| | - Xavier Alvarez
- 1 Tulane National Primate Research Center, Covington, Louisiana
| | - Andrew A Lackner
- 1 Tulane National Primate Research Center, Covington, Louisiana.,2 Tulane University Health Sciences, New Orleans, Louisiana; and
| | - Joel S Bader
- 3 Whitaker Biomedical Engineering Institute, Whiting School of Engineering, Johns Hopkins University, Baltimore, Maryland
| | - Smriti Mehra
- 5 Department of Pathobiological Sciences, Louisiana State University School of Veterinary Medicine, Baton Rouge, Louisiana
| | - Deepak Kaushal
- 1 Tulane National Primate Research Center, Covington, Louisiana.,2 Tulane University Health Sciences, New Orleans, Louisiana; and
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7
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Kaushal D, Foreman TW, Gautam US, Alvarez X, Adekambi T, Rangel-Moreno J, Golden NA, Johnson AMF, Phillips BL, Ahsan MH, Russell-Lodrigue KE, Doyle LA, Roy CJ, Didier PJ, Blanchard JL, Rengarajan J, Lackner AA, Khader SA, Mehra S. Mucosal vaccination with attenuated Mycobacterium tuberculosis induces strong central memory responses and protects against tuberculosis. Nat Commun 2015; 6:8533. [PMID: 26460802 PMCID: PMC4608260 DOI: 10.1038/ncomms9533] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [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: 03/17/2015] [Accepted: 09/02/2015] [Indexed: 02/07/2023] Open
Abstract
Tuberculosis (TB) is a global pandaemic, partially due to the failure of vaccination approaches. Novel anti-TB vaccines are therefore urgently required. Here we show that aerosol immunization of macaques with the Mtb mutant in SigH (MtbΔsigH) results in significant recruitment of inducible bronchus-associated lymphoid tissue (iBALT) as well as CD4+ and CD8+ T cells expressing activation and proliferation markers to the lungs. Further, the findings indicate that pulmonary vaccination with MtbΔsigH elicited strong central memory CD4+ and CD8+ T-cell responses in the lung. Vaccination with MtbΔsigH results in significant protection against a lethal TB challenge, as evidenced by an approximately three log reduction in bacterial burdens, significantly diminished clinical manifestations and granulomatous pathology and characterized by the presence of profound iBALT. This highly protective response is virtually absent in unvaccinated and BCG-vaccinated animals after challenge. These results suggest that future TB vaccine candidates can be developed on the basis of MtbΔsigH. BCG, the only vaccine currently used against tuberculosis, confers only limited protection. Here the authors show that mucosal immunization of macaques with an attenuated strain of Mycobacterium tuberculosis confers a high level of protection from a lethal challenge with the bacterium.
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Affiliation(s)
- Deepak Kaushal
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA.,Department of Microbiology and Immunology, Tulane Health Sciences Center, New Orleans, Louisiana 70112, USA
| | - Taylor W Foreman
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA.,Biomedical Sciences Graduate Program, Tulane Health Sciences Center, New Orleans, Louisiana 70112, USA
| | - Uma S Gautam
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA
| | - Xavier Alvarez
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA
| | - Toidi Adekambi
- Yerkes National Primate Research Center, Atlanta, Georgia 30329, USA.,Emory Vaccine Center, Atlanta, Georgia 30329, USA
| | | | - Nadia A Golden
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA
| | | | - Bonnie L Phillips
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA.,Biomedical Sciences Graduate Program, Tulane Health Sciences Center, New Orleans, Louisiana 70112, USA
| | - Muhammad H Ahsan
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA
| | | | - Lara A Doyle
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA
| | - Chad J Roy
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA
| | - Peter J Didier
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA
| | - James L Blanchard
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA
| | - Jyothi Rengarajan
- Yerkes National Primate Research Center, Atlanta, Georgia 30329, USA.,Emory Vaccine Center, Atlanta, Georgia 30329, USA
| | - Andrew A Lackner
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA.,Department of Microbiology and Immunology, Tulane Health Sciences Center, New Orleans, Louisiana 70112, USA.,Department of Pathology, Tulane Health Sciences Center, New Orleans, Louisiana 70112, USA
| | - Shabaana A Khader
- Department of Molecular Microbiology, Washington University at St Louis, St Louis, Missouri 63110, USA
| | - Smriti Mehra
- Tulane National Primate Research Center, Covington, Louisiana 70433, USA.,Center for Biomedical Research Excellence, Louisiana State University School of Veterinary Medicine, Baton Rouge, Louisiana 70803, USA.,Department of Pathobiological Sciences, Louisiana State University School of Veterinary Medicine, Baton Rouge, Louisiana 70803, USA
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8
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Mothé BR, Lindestam Arlehamn CS, Dow C, Dillon MBC, Wiseman RW, Bohn P, Karl J, Golden NA, Gilpin T, Foreman TW, Rodgers MA, Mehra S, Scriba TJ, Flynn JL, Kaushal D, O'Connor DH, Sette A. The TB-specific CD4(+) T cell immune repertoire in both cynomolgus and rhesus macaques largely overlap with humans. Tuberculosis (Edinb) 2015; 95:722-735. [PMID: 26526557 DOI: 10.1016/j.tube.2015.07.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 07/23/2015] [Accepted: 07/26/2015] [Indexed: 01/05/2023]
Abstract
Non-human primate (NHP) models of tuberculosis (TB) immunity and pathogenesis, especially rhesus and cynomolgus macaques, are particularly attractive because of the high similarity of the human and macaque immune systems. However, little is known about the MHC class II epitopes recognized in macaques, thus hindering the establishment of immune correlates of immunopathology and protective vaccination. We characterized immune responses in rhesus macaques vaccinated against and/or infected with Mycobacterium tuberculosis (Mtb), to a panel of antigens currently in human vaccine trials. We defined 54 new immunodominant CD4(+) T cell epitopes, and noted that antigens immunodominant in humans are also immunodominant in rhesus macaques, including Rv3875 (ESAT-6) and Rv3874 (CFP10). Pedigree and inferred restriction analysis demonstrated that this phenomenon was not due to common ancestry or inbreeding, but rather presentation by common alleles, as well as, promiscuous binding. Experiments using a second cohort of rhesus macaques demonstrated that a pool of epitopes defined in the previous experiments can be used to detect T cell responses in over 75% of individual monkeys. Additionally, 100% of cynomolgus macaques, irrespective of their latent or active TB status, responded to rhesus and human defined epitope pools. Thus, these findings reveal an unexpected general repertoire overlap between MHC class II epitopes recognized in both species of macaques and in humans, showing that epitope pools defined in humans can also be used to characterize macaque responses, despite differences in species and antigen exposure. The results have general implications for the evaluation of new vaccines and diagnostics in NHPs, and immediate applicability in the setting of macaque models of TB.
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Affiliation(s)
- Bianca R Mothé
- Department of Biology, CSUSM, San Marcos, CA 92096, USA; La Jolla Institute for Allergy & Immunology, La Jolla, CA 92037, USA.
| | | | - Courtney Dow
- Department of Biology, CSUSM, San Marcos, CA 92096, USA
| | - Myles B C Dillon
- La Jolla Institute for Allergy & Immunology, La Jolla, CA 92037, USA
| | - Roger W Wiseman
- Wisconsin National Primate Research Center and Department of Pathology and Laboratory Medicine, UW-Madison, Madison, WI 53706, USA
| | - Patrick Bohn
- Wisconsin National Primate Research Center and Department of Pathology and Laboratory Medicine, UW-Madison, Madison, WI 53706, USA
| | - Julie Karl
- Wisconsin National Primate Research Center and Department of Pathology and Laboratory Medicine, UW-Madison, Madison, WI 53706, USA
| | - Nadia A Golden
- Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Trey Gilpin
- Department of Biology, CSUSM, San Marcos, CA 92096, USA
| | - Taylor W Foreman
- Tulane National Primate Research Center, Covington, LA 70433, USA
| | - Mark A Rodgers
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15216, USA
| | - Smriti Mehra
- Tulane National Primate Research Center, Covington, LA 70433, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University Baton Rouge, LA 70803, USA
| | - Thomas J Scriba
- South African Tuberculosis Vaccine Initiative, Institute of Infectious Disease and Molecular Medicine, and Department of Pediatrics and Child Health, University of Cape Town, Cape Town 7925, South Africa
| | - JoAnne L Flynn
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15216, USA
| | - Deepak Kaushal
- Tulane National Primate Research Center, Covington, LA 70433, USA
| | - David H O'Connor
- Wisconsin National Primate Research Center and Department of Pathology and Laboratory Medicine, UW-Madison, Madison, WI 53706, USA
| | - Alessandro Sette
- La Jolla Institute for Allergy & Immunology, La Jolla, CA 92037, USA
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Gautam US, McGillivray A, Mehra S, Didier PJ, Midkiff CC, Kissee RS, Golden NA, Alvarez X, Niu T, Rengarajan J, Sherman DR, Kaushal D. DosS Is required for the complete virulence of mycobacterium tuberculosis in mice with classical granulomatous lesions. Am J Respir Cell Mol Biol 2015; 52:708-16. [PMID: 25322074 DOI: 10.1165/rcmb.2014-0230oc] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) must counter hypoxia within granulomas to persist. DosR, in concert with sensor kinases DosS and DosT, regulates the response to hypoxia. Yet Mtb lacking functional DosR colonize the lungs of C57Bl/6 mice, presumably owing to the lack of organized lesions with sufficient hypoxia in that model. We compared the phenotype of the Δ-dosR, Δ-dosS, and Δ-dosT mutants to Mtb using C3HeB/FeJ mice, an alternate mouse model where lesions develop hypoxia. C3HeB/FeJ mice were infected via aerosol. The progression of infection was analyzed by tissue bacterial burden and histopathology. A measure of the comparative global immune responses was also analyzed. Although Δ-dosR and Δ-dosT grew comparably to wild-type Mtb, Δ-dosS exhibited a significant defect in bacterial burden and pathology in vivo, accompanied by ablated proinflammatory response. Δ-dosS retained the ability to induce DosR. The Δ-dosS mutant was also attenuated in murine macrophages ex vivo, with evidence of reduced expression of the proinflammatory signature. Our results show that DosS, but not DosR and DosT, is required by Mtb to survive in C3HeB/FeJ mice. The attenuation of Δ-dosS is not due to its inability to induce the DosR regulon, nor is it a result of the accumulation of hypoxia. That the in vivo growth restriction of Δ-dosS could be mimicked ex vivo suggested sensitivity to macrophage oxidative burst. Anoxic caseous centers within tuberculosis lesions eventually progress to cavities. Our results provide greater insight into the molecular mechanisms of Mtb persistence within host lungs.
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Mehra S, Foreman TW, Didier PJ, Ahsan MH, Hudock TA, Kissee R, Golden NA, Gautam US, Johnson AM, Alvarez X, Russell-Lodrigue KE, Doyle LA, Roy CJ, Niu T, Blanchard JL, Khader SA, Lackner AA, Sherman DR, Kaushal D. The DosR Regulon Modulates Adaptive Immunity and Is Essential for Mycobacterium tuberculosis Persistence. Am J Respir Crit Care Med 2015; 191:1185-96. [PMID: 25730547 DOI: 10.1164/rccm.201408-1502oc] [Citation(s) in RCA: 119] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
RATIONALE Hypoxia promotes dormancy by causing physiologic changes to actively replicating Mycobacterium tuberculosis. DosR controls the response of M. tuberculosis to hypoxia. OBJECTIVES To understand DosR's contribution in the persistence of M. tuberculosis, we compared the phenotype of various DosR regulon mutants and a complemented strain to M. tuberculosis in macaques, which faithfully model M. tuberculosis infection. METHODS We measured clinical and microbiologic correlates of infection with M. tuberculosis relative to mutant/complemented strains in the DosR regulon, studied lung pathology and hypoxia, and compared immune responses in lung using transcriptomics and flow cytometry. MEASUREMENTS AND MAIN RESULTS Despite being able to replicate initially, mutants in DosR regulon failed to persist or cause disease. On the contrary, M. tuberculosis and a complemented strain were able to establish infection and tuberculosis. The attenuation of pathogenesis in animals infected with the mutants coincided with the appearance of a Th1 response and organization of hypoxic lesions wherein M. tuberculosis expressed dosR. The lungs of animals infected with the mutants (but not the complemented strain) exhibited early transcriptional signatures of T-cell recruitment, activation, and proliferation associated with an increase of T cells expressing homing and proliferation markers. CONCLUSIONS Delayed adaptive responses, a hallmark of M. tuberculosis infection, not only lead to persistence but also interfere with the development of effective antituberculosis vaccines. The DosR regulon therefore modulates both the magnitude and the timing of adaptive immune responses in response to hypoxia in vivo, resulting in persistent infection. Hence, DosR regulates key aspects of the M. tuberculosis life cycle and limits lung pathology.
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McGillivray A, Golden NA, Kaushal D. The Mycobacterium tuberculosis Clp gene regulator is required for in vitro reactivation from hypoxia-induced dormancy. J Biol Chem 2014; 290:2351-67. [PMID: 25422323 DOI: 10.1074/jbc.m114.615534] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb) is the leading cause of death from an infectious disease worldwide and is the causative agent of tuberculosis (Chao, M. C., and Rubin, E. J. (2010) Annu. Rev. Microbiol. 64, 293-311). Throughout infection, Mtb encounters a variety of host pressures. Thus, responding to these host stresses via the induction of multiple regulatory networks is needed for survival within the host. The Clp protease gene regulator, Rv2745c (clgR), is induced in response to environmental stress conditions, implicating its potential role in Mtb pathogenesis. Transcriptional activation of genes downstream of Rv2745c occurs in a condition-dependent manner. Our isogenic Mtb:ΔRv2745c mutant expresses a significantly different phenotype upon reaeration conditions. Transcriptional analysis revealed differential gene expression profiles relative to wild-type Mtb. Rv2745c is strongly induced in response to hypoxic and reaeration conditions, implicating a role of Rv2745c in vivo during both establishment of infection and reactivation. We found dysregulation of downstream genes within both the σ(H)/σ(E) regulon as well as the dosR regulon in the isogenic mutant, Mtb:ΔRv2745c. Upon hypoxic and reaeration conditions, Clp protease induction occurred within wild-type Mtb, indicating that activation of clgR, which subsequently leads to Clp protease induction, is crucial for degradation of misfolded proteins and ultimately survival of Mtb upon specific stress conditions. Our data indicate the diverse response of Rv2745c, σ(H) and σ(E) in response to a variety of stress conditions. Activation of Rv2745c in response to various stress conditions leads to differential activation of downstream genes, indicating the diverse role of Rv2745c and its importance for Mtb survival in vivo.
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Affiliation(s)
- Amanda McGillivray
- From the Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana 70433
| | - Nadia A Golden
- From the Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana 70433
| | - Deepak Kaushal
- From the Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana 70433
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Luo Q, Mehra S, Golden NA, Kaushal D, Lacey MR. Identification of biomarkers for tuberculosis susceptibility via integrated analysis of gene expression and longitudinal clinical data. Front Genet 2014; 5:240. [PMID: 25104956 PMCID: PMC4109430 DOI: 10.3389/fgene.2014.00240] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [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: 04/25/2014] [Accepted: 07/03/2014] [Indexed: 11/21/2022] Open
Abstract
Tuberculosis (TB) is an infectious disease caused by the bacteria Mycobacterium tuberculosis (Mtb) that affects millions of people worldwide. The majority of individuals who are exposed to Mtb develop latent infections, in which an immunological response to Mtb antigens is present but there is no clinical evidence of disease. Because currently available tests cannot differentiate latent individuals who are at low risk from those who are highly susceptible to developing active disease, there is considerable interest in the identification of diagnostic biomarkers that can predict reactivation of latent TB. We present results from our analysis of a controlled longitudinal experiment in which a group of rhesus macaques were exposed to a low dose of Mtb to study their progression to latent infection or active disease. Subsets of the animals were then euthanized at scheduled time points, and granulomas taken from their lungs were assayed for gene expression using microarrays. The clinical profiles associated with the animals following Mtb exposure revealed considerable variability, and we developed models for the disease trajectory for each subject using a Bayesian hierarchical B-spline approach. Disease severity estimates were derived from these fitted curves and included as covariates in linear models to identify genes significantly associated with disease progression. Our results demonstrate that the incorporation of clinical data increases the value of information extracted from the expression profiles and contributes to the identification of predictive biomarkers for TB susceptibility.
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Affiliation(s)
- Qingyang Luo
- Mathematics Department, Tulane University New Orleans, LA, USA
| | - Smriti Mehra
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Covington, LA, USA
| | - Nadia A Golden
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Covington, LA, USA
| | - Deepak Kaushal
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Tulane University Covington, LA, USA
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Mehra S, Golden NA, Stuckey K, Didier PJ, Doyle LA, Russell-Lodrigue KE, Sugimoto C, Hasegawa A, Sivasubramani SK, Roy CJ, Alvarez X, Kuroda MJ, Blanchard JL, Lackner AA, Kaushal D. The Mycobacterium tuberculosis stress response factor SigH is required for bacterial burden as well as immunopathology in primate lungs. J Infect Dis 2012; 205:1203-13. [PMID: 22402035 DOI: 10.1093/infdis/jis102] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Sigma H (sigH) is a major Mycobacterium tuberculosis (Mtb) stress response factor. It is induced in response to heat, oxidative stress, cell wall damage, and hypoxia. Infection of macrophages with the Δ-sigH mutant generates more potent innate immune response than does infection with Mtb. The mutant is attenuated for pathology in mice. METHODS We used a nonhuman primate (NHP) model of acute tuberculosis, to better understand the phenotype of the Δ-sigH mutant in vivo. NHPs were infected with high doses of Mtb or the mutant, and the progression of tuberculosis was analyzed in both groups using clinical, pathological, microbiological, and immunological parameters. RESULTS Animals exposed to Mtb rapidly progressed to acute pulmonary tuberculosis as indicated by worsening clinical correlates, high lung bacterial burden, and granulomatous immunopathology. All the animals rapidly succumbed to tuberculosis. On the other hand, the NHPs exposed to the Mtb:Δ-sigH mutant did not exhibit acute tuberculosis, instead showing significantly blunted disease. These NHPs survived the entire duration of the study. CONCLUSIONS The Mtb:Δ-sigH mutant is completely attenuated for bacterial burden as well as immunopathology in NHPs. SigH and its regulon are required for complete virulence in primates. Further studies are needed to identify the molecular mechanism of this attenuation.
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Affiliation(s)
- Smriti Mehra
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, LA 70433, USA
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Mehra S, Golden NA, Dutta NK, Midkiff CC, Alvarez X, Doyle LA, Asher M, Russell-Lodrigue K, Monjure C, Roy CJ, Blanchard JL, Didier PJ, Veazey RS, Lackner AA, Kaushal D. Reactivation of latent tuberculosis in rhesus macaques by coinfection with simian immunodeficiency virus. J Med Primatol 2011; 40:233-43. [PMID: 21781131 DOI: 10.1111/j.1600-0684.2011.00485.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Tuberculosis (TB) and AIDS together present a devastating public health challenge. Over 3 million deaths every year are attributed to these twin epidemics. Annually, ∼11 million people are coinfected with HIV and Mycobacterium tuberculosis (Mtb). AIDS is thought to alter the spontaneous rate of latent TB reactivation. METHODOLOGY Macaques are excellent models of both TB and AIDS. Therefore, it is conceivable that they can also be used to model coinfection. Using clinical, pathological, and microbiological data, we addressed whether latent TB infection in rhesus macaques can be reactivated by infection with simian immunodeficiency virus (SIV). RESULTS A low-dose aerosol infection of rhesus macaques with Mtb caused latent, asymptomatic TB infection. Infection of macaques exhibiting latent TB with a rhesus-specific strain of SIV significantly reactivated TB. CONCLUSIONS Rhesus macaques are excellent model of TB/AIDS coinfection and can be used to study the phenomena of TB latency and reactivation.
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Affiliation(s)
- Smriti Mehra
- Divisions of Bacteriology & Parasitology, Tulane National Primate Research Center, Covington, LA 70433, USA
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