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Surdel MC, Anderson PN, Hahn BL, Coburn J. Hematogenous dissemination of pathogenic and non-pathogenic Leptospira in a short-term murine model of infection. Front Cell Infect Microbiol 2022; 12:917962. [PMID: 35923802 PMCID: PMC9339599 DOI: 10.3389/fcimb.2022.917962] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 06/27/2022] [Indexed: 01/19/2023] Open
Abstract
Leptospirosis is an emerging zoonosis caused by pathogenic Leptospira spp. Because rodents are natural hosts of Leptospira, rodent models of pathogenesis have been limited, but are valuable to understand infection in reservoir animals even in the absence of disease. Mouse models of infection provide advantages due to genetic tractability, so developing murine models of Leptospira infection is crucial for further understanding the biology of this organism. Previously our laboratory developed a short-term murine model of Borrelia burgdorferi hematogenous dissemination to investigate the role of adhesion proteins on bacterial survival and dissemination within a host. Here we adapt this model to Leptospira. C3H/HeJ mice are anesthetized, inoculated intravenously, and then bacteria are allowed to circulate for up to twenty-four hours. Mice are euthanized, perfused with saline, and tissues are harvested for culture and DNA purification. Bacterial burdens are determined by quantitative PCR. Reproducible burdens of bacteria were found in tissues upon inoculation with pathogens and non-pathogens, demonstrating the utility of this model to probe different Leptospira species and strains. Pathogenic L. interrogans has a significantly higher burden in blood, liver, kidney, and bladder at one-hour post-inoculation when compared to non-pathogenic L. biflexa. Colonization of the kidney is essential to the life cycle of pathogenic Leptospira in nature. Measurable burdens of non-pathogenic L. biflexa were found in numerous organs and live leptospires were recovered from blood samples for at least three hours post-inoculation, contrary to the previous belief that non-pathogenic leptospires are rapidly cleared. This short-term murine model of Leptospira hematogenous dissemination will allow for the interrogation of virulence factors potentially important for tissue colonization and evasion of host defenses, and represents a novel animal model for investigating determinants of Leptospira infection.
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Affiliation(s)
- Matthew C. Surdel
- Department of Medicine, Division of Infectious Diseases, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Phillip N. Anderson
- Department of Medicine, Division of Infectious Diseases, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Beth L. Hahn
- Department of Medicine, Division of Infectious Diseases, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Jenifer Coburn
- Department of Medicine, Division of Infectious Diseases, Medical College of Wisconsin, Milwaukee, WI, United States
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States
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Shetty A, Kundu S, Vernel-Pauillac F, Ratet G, Werts C, Gomes-Solecki M. Transient Presence of Live Leptospira interrogans in Murine Testes. Microbiol Spectr 2022; 10:e0277521. [PMID: 35446113 PMCID: PMC9241917 DOI: 10.1128/spectrum.02775-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 03/25/2022] [Indexed: 01/01/2023] Open
Abstract
Analysis of Leptospira dissemination and colonization of sex organs in rodents is of significant value as it queries the possibility of mammal-to-mammal venereal transmission. The aim of our study was to evaluate the presence and viability of Leptospira interrogans in testes of mice using models of infection that we previously developed. Using sublethal and lethal doses of bioluminescent strains of L. interrogans serovars Manilae and Copenhageni, we visualized the presence of leptospires in testes of C57BL/6 mice as early as 30 min and up to days 3-4 postinfection. This was confirmed by qPCR for the Copenhageni serovar after lethal infection of C3H/HeJ mice. In this model, no histopathological changes were noticed in testis. We further studied persistence of serovar Copenhageni in C3H/HeJ testes after lethal and sublethal infection, with different doses of leptospires. No viable leptospires were recovered from testes of lethally infected mice. However, we found live culturable Leptospira in testes of 19/19 (100%) sublethally infected mice at the acute phase but not at 15 days postinfection, which corresponds to the chronic phase of renal colonization. The data suggest that colonization of testes with live and potentially infectious leptospires is transient and limited to the spirochetemic phase of infection. Further studies are necessary to evaluate if presence of Leptospira in testes of mice leads to excretion in semen and to venereal transmission to female mice. IMPORTANCE Analysis of venereal transmission of Leptospira is important to determine if direct animal to animal transmission occurs, which could impact measures to prevent and treat leptospirosis. The goal of this study was to determine if live Leptospira colonize mouse testes. We found that colonization of mouse testes with live Leptospira was transient and limited to the acute spirochetemic phase of infection and that transient colonization of the testes was insufficient to cause histopathological changes.
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Affiliation(s)
- Advait Shetty
- Department of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Suman Kundu
- Department of Microbiology, Immunology and Biochemistry, The University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Frédérique Vernel-Pauillac
- Institut Pasteur, Université de Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la paroi bactérienne, Paris, France
| | - Gwendoline Ratet
- Institut Pasteur, Université de Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la paroi bactérienne, Paris, France
| | - Catherine Werts
- Institut Pasteur, Université de Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la paroi bactérienne, Paris, France
| | - Maria Gomes-Solecki
- Department of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, Tennessee, USA
- Department of Microbiology, Immunology and Biochemistry, The University of Tennessee Health Science Center, Memphis, Tennessee, USA
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Fortes-Gabriel E, Guedes MS, Shetty A, Gomes CK, Carreira T, Vieira ML, Esteves L, Mota-Vieira L, Gomes-Solecki M. Enzyme immunoassays (EIA) for serodiagnosis of human leptospirosis: specific IgG3/IgG1 isotyping may further inform diagnosis of acute disease. PLoS Negl Trop Dis 2022; 16:e0010241. [PMID: 35196321 PMCID: PMC8901056 DOI: 10.1371/journal.pntd.0010241] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 03/07/2022] [Accepted: 02/09/2022] [Indexed: 12/24/2022] Open
Abstract
The laborious microscopic agglutination test (MAT) is the gold standard serologic test for laboratory diagnosis of leptospirosis. We developed EIA based serologic assays using recombinant proteins (rLigA, rLigB, rLipL32) and whole-cell extracts from eight Leptospira serovars as antigen and assessed the diagnostic performance of the new assay within each class, against MAT positive (MAT+) human sera panels from Portugal/PT (n = 143) and Angola/AO (n = 100). We found that a combination of recombinant proteins rLigA, rLigB and rLipL32 correctly identified antigen-specific IgG from patients with clinical and laboratory confirmed leptospirosis (MAT+) with 92% sensitivity and ~ 97% specificity (AUC 0.974) in serum from the provinces of Luanda (LDA) and Huambo (HBO) in Angola. A combination of whole cell extracts of L. interrogans sv Copenhageni (LiC), L. kirschneri Mozdok (LkM), L. borgpetersenii Arborea (LbA) and L. biflexa Patoc (LbP) accurately identified patients with clinical and laboratory confirmed leptospirosis (MAT+) with 100% sensitivity and ~ 98% specificity for all provinces of Angola and Portugal (AUC: 0.997 for AO/LDA/HBO, 1.000 for AO/HLA, 0.999 for PT/AZ and 1.000 for PT/LIS). Interestingly, we found that MAT+ IgG+ serum from Angola had a significantly higher presence of IgD and that IgG3/IgG1 isotypes were significantly increased in the MAT+ IgG+ serum from Portugal. Given that IgM/IgD class and IgG3/IgG1 specific isotypes are produced in the earliest course of infection, immunoglobulin G isotyping may be used to inform diagnosis of acute leptospirosis. The speed, ease of use and accuracy of EIA tests make them excellent alternatives to the laborious and expensive MAT for screening acute infection in areas where circulating serovars of pathogenic Leptospira are well defined.
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Affiliation(s)
- Elsa Fortes-Gabriel
- Instituto Superior Técnico Militar—Estado Maior General das Forças Armadas Angolanas, Luanda, Angola,Immuno Technologies Inc, Memphis, Tennessee, United States of America
| | | | - Advait Shetty
- Department of Pharmaceutical Sciences—University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | | | - Teresa Carreira
- Instituto de Higiene e Medicina Tropical—Universidade Nova de Lisboa, Lisbon, Portugal
| | - Maria Luísa Vieira
- Instituto de Higiene e Medicina Tropical—Universidade Nova de Lisboa, Lisbon, Portugal
| | - Lisa Esteves
- Molecular Genetics and Pathlogy Unit—Hospital do Divino Espírito Santo de Ponta Delgada, São Miguel Island—Azores, Portugal
| | - Luísa Mota-Vieira
- Molecular Genetics and Pathlogy Unit—Hospital do Divino Espírito Santo de Ponta Delgada, São Miguel Island—Azores, Portugal,Azores Genetics Research Group—Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Maria Gomes-Solecki
- Immuno Technologies Inc, Memphis, Tennessee, United States of America,Department of Pharmaceutical Sciences—University of Tennessee Health Science Center, Memphis, Tennessee, United States of America,* E-mail:
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Phillip K, Nair N, Samanta K, Azevedo JF, Brown GD, Petersen CA, Gomes-Solecki M. Maternal transfer of neutralizing antibodies to B. burgdorferi OspA after oral vaccination of the rodent reservoir. Vaccine 2021; 39:4320-4327. [PMID: 34172332 PMCID: PMC8495753 DOI: 10.1016/j.vaccine.2021.06.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 05/23/2021] [Accepted: 06/10/2021] [Indexed: 11/26/2022]
Abstract
Lyme Disease presents unique challenges for public health. Transfer of protective antibodies between mothers and offspring should occur after vaccination of mice. We present new evidence for maternal transfer of oral vaccine induced neutralizing anti-OspA IgG antibodies to mouse pups mainly through ingestion of colostrum. We found a strong statistical correlation of antibody transfer between mothers that produced the most robust IgG response to OspA and their respective pups. OspA-specific antibody was detected as early as 24 h after birth and protective levels of antibodies lasted until ~5 weeks of age in the majority of pups but persisted in some mice until 9 weeks. This was further supported by detection of neutralizing antibodies in serum of all pups at 2-3 weeks after birth and in some offspring adult mice at 9 weeks of age. A clear association was found between robust antibody responses in mothers and the length of time antibody persisted in the respective pups using a novel longitudinal Bayesian model. These factors are likely to impact the enzootic cycle of B. burgdorferi if reservoir targeted OspA-based vaccination interventions are implemented.
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Affiliation(s)
- Kathryn Phillip
- University of Tennessee Health Science Center Department of Comparative Medicine
| | - Nisha Nair
- University of Tennessee Health Science Center Department of Microbiology, Immunology and Biochemistry
| | - Kamalika Samanta
- University of Tennessee Health Science Center Department of Microbiology, Immunology and Biochemistry
| | - Jose F. Azevedo
- University of Tennessee Health Science Center Department of Microbiology, Immunology and Biochemistry
| | | | - Christine A. Petersen
- University of Iowa Department of Epidemiology, Center for Emerging Infectious Diseases
| | - Maria Gomes-Solecki
- University of Tennessee Health Science Center, Department of Microbiology, Immunology and Biochemistry, United States.
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Nair N, Guedes MS, Hajjar AM, Werts C, Gomes-Solecki M. Role of TLR4 in Persistent Leptospira interrogans Infection: A Comparative In Vivo Study in Mice. Front Immunol 2021; 11:572999. [PMID: 33519799 PMCID: PMC7843520 DOI: 10.3389/fimmu.2020.572999] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 11/30/2020] [Indexed: 12/13/2022] Open
Abstract
Toll-Like Receptor (TLR) 4, the LPS receptor, plays a central role in the control of leptospirosis and absence of TLR4 results in lethal infection in mice. Because human TLR4 does not sense the atypical leptospiral-LPS, we hypothesized that TLR4/MD-2 humanized transgenic mice (huTLR4) may be more susceptible to leptospirosis than wild-type mice, and thus may constitute a model of acute human leptospirosis. We infected huTLR4 mice, which express human TLR4 but not murine TLR4, with a high dose of L. interrogans serovar Copenhageni FioCruz (Leptospira) in comparison to C57BL/6J wild-type (WT) and, as a control, a congenic strain in which the tlr4 coding sequences are deleted (muTLR4Lps-del). We show that the huTLR4 gene is fully functional in the murine background. We found that dissemination of Leptospira in blood, shedding in urine, colonization of the kidney and overall kinetics of leptospirosis progression is equivalent between WT and huTLR4 C57BL/6J mice. Furthermore, inflammation of the kidney appeared to be subdued in huTLR4 compared to WT mice in that we observed less infiltrates of mononuclear lymphocytes, less innate immune markers and no relevant differences in fibrosis markers. Thus, huTLR4 mice showed less inflammation and kidney pathology, and are not more susceptible to leptospirosis than WT mice. This study is significant as it indicates that one intact TLR4 gene, be it mouse or human, is necessary to control acute leptospirosis.
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Affiliation(s)
- Nisha Nair
- Department of Microbiology, Immunology and Biochemistry, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Mariana S. Guedes
- Department of Microbiology, Immunology and Biochemistry, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Adeline M. Hajjar
- Department of Comparative Medicine, University of Washington, Seattle, WA, United States
| | - Catherine Werts
- Institut Pasteur, Biology and Genetics of the Bacterial Cell Wall Unit, Paris, France,CNRS, UMR 2001 Microbiologie intégrative et Moléculaire, Paris, France
| | - Maria Gomes-Solecki
- Department of Microbiology, Immunology and Biochemistry, The University of Tennessee Health Science Center, Memphis, TN, United States,*Correspondence: Maria Gomes-Solecki,
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