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Gonçalves-de-Albuquerque CF, Cunha CMCD, Castro LVGD, Martins CDA, Barnese MRC, Burth P, Younes-Ibrahim M. Cellular Pathophysiology of Leptospirosis: Role of Na/K-ATPase. Microorganisms 2023; 11:1695. [PMID: 37512868 PMCID: PMC10383190 DOI: 10.3390/microorganisms11071695] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2023] [Revised: 06/04/2023] [Accepted: 06/19/2023] [Indexed: 07/30/2023] Open
Abstract
Inada and Ido identified Leptospira sp. as the pathogen responsible for Weil's Disease in 1915. Later, it was confirmed that Leptospira causes leptospirosis. The host microorganism's interaction at the cellular level remained misunderstood for many years. Although different bacterial components have been isolated and purified, the complexity of the molecular interactions between these components and the host and the molecular mechanisms responsible for the systemic dysfunctions still needs to be fully unveiled. Leptospirosis affects virtually all animal species. Its cellular pathophysiology must involve a ubiquitous cellular mechanism in all eukaryotes. Na/K-ATPase is the molecular target of the leptospiral endotoxin (glycolipoprotein-GLP). Na/K-ATPase dysfunctions on different types of cells give rise to the organ disorders manifested in leptospirosis. Concomitantly, the development of a peculiar metabolic disorder characterized by dyslipidemia, with increased levels of circulating free fatty acids and an imbalance in the fatty acid/albumin molar ratio, triggers events of cellular lipotoxicity. Synergistically, multiple molecular stimuli are prompted during the infection, activating inflammasomes and Na/K-ATPase signalosome, leading to pro-inflammatory and metabolic alterations during leptospirosis. Leptospirosis involves diverse molecular mechanisms and alteration in patient inflammatory and metabolic status. Nonetheless, Na/K-ATPase is critical in the disease, and it is targeted by GLP, its components, and other molecules, such as fatty acids, that inhibit or trigger intracellular signaling through this enzyme. Herein, we overview the role of Na/K-ATPase during leptospirosis infection as a potential therapeutic target or an indicator of disease severity.
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Affiliation(s)
| | - Carolina Medina Coeli da Cunha
- Laboratory of Immunopharmacology, Department of Physiology, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro 20211-030, Brazil
- Neuroscience Graduate Program, Federal Fluminense University (UFF), Niteroi 24000-000, Brazil
| | | | - Caroline de Azevedo Martins
- School of Medicine and Surgery, Federal University of the State of Rio de Janeiro (UNIRIO), Rio de Janeiro 20270-901, Brazil
| | | | - Patrícia Burth
- Laboratory of Enzymology and Cellular Signaling, Department of Cellular and Molecular Biology, Federal Fluminense University (UFF), Niteroi 24000-000, Brazil
| | - Mauricio Younes-Ibrahim
- FISCLINEX Postgraduate Program, State University of Rio de Janeiro (UERJ), Rio de Janeiro 20550-900, Brazil
- Department of Medicine, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro 22453-900, Brazil
- State University of Rio de Janeiro (UERJ), Rio de Janeiro 20550-900, Brazil
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2
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Sumaiya K, Akino Mercy CS, Muralitharan G, Hajinur Hirad A, Alarfaj AA, Natarajaseenivasan K. Assessment of Serum Macrophage Migration Inhibitory Factor (MIF) as an Early Diagnostic Marker of Leptospirosis. Front Cell Infect Microbiol 2022; 11:781476. [PMID: 35237527 PMCID: PMC8884337 DOI: 10.3389/fcimb.2021.781476] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/27/2021] [Indexed: 12/26/2022] Open
Abstract
The search for valuable early diagnostic markers for leptospirosis is ongoing. The aim of the present study was to evaluate the diagnostic value of macrophage migration inhibitory factor (MIF) for leptospirosis. MIF is an immunoregulatory cytokine secreted by a variety of cell types involved in immune response and the pathogenesis of various diseases. It was previously described as a severity predictor of diseases. Samples of 142 leptospirosis cases, 101 other febrile cases, and 57 healthy controls were studied. The prevalence of leptospirosis was 47.3%. Autumnalis, Australis, and Canicola were the highly prevalent leptospiral serovars with a microscopic agglutination test (MAT) titer in the range 1:80–1:2,560. Enzyme-linked immunosorbent assay (ELISA) of MIF was carried out to measure the serum MIF levels. We found that the serum MIF levels [median, (interquartile range)] were significantly (p < 0.001) elevated in different clinical forms of leptospirosis, such as febrile illness [7.5 ng/ml (5.32–8.97)], pulmonary hemorrhage [13.2 ng/ml (11.77–16.72)], Weil’s syndrome [8.8 ng/ml (7.25–9.95)], and renal failure [8.6 ng/ml (7.18–10.5)], than in healthy controls [0.65n g/ml (0.5–1.1)]. Serum MIF had sensitivity, specificity, positive predictive value, and negative predictive value of 100%, >90%, >90%, and 100%, respectively. Receiver operating characteristic (ROC) analysis revealed that the serum MIF levels between leptospirosis cases and control subjects had an area under the curve (AUC) value of >0.9 (p < 0.0001). In leptospirosis patients, elevation of serum MIF was significantly (p < 0.001) higher in severe cases with organ dysfunction [10 ng/ml (7.8–14.5)] than that in mild febrile cases [7.5 ng/ml (5.32–8.97)], with the difference of 2.5 indicating that serum MIF acts as a predictor of leptospirosis severity. Pearson’s correlation test demonstrated that the serum MIF level was strongly correlated (r = 0.75, p < 0.0001) with disease progression. The median lethal dose (LD50) of leptospiral lipopolysaccharide (LPS) in BALB/c mice was determined to be 20 mg/kg, which gave rise to endotoxemia. Leptospiral LPS triggered the upregulation of MIF expression at 24 h post-infection, which reached the peak level at 24 h post-treatment in THP-1 cells and showed elevated MIF expressions in different tissues of BALB/c mice at the early stage of infection. Taken together, MIF is an early-phase cytokine that could serve as a rapid diagnostic marker for leptospirosis.
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Affiliation(s)
- Krishnamoorthi Sumaiya
- Medical Microbiology Laboratory, Department of Microbiology, Centre for Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli, India
| | - Charles Solomon Akino Mercy
- Medical Microbiology Laboratory, Department of Microbiology, Centre for Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli, India
| | - Gangatharan Muralitharan
- Medical Microbiology Laboratory, Department of Microbiology, Centre for Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli, India
| | - Abdurahman Hajinur Hirad
- Department of Botany & Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Abdullah A. Alarfaj
- Department of Botany & Microbiology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Kalimuthusamy Natarajaseenivasan
- Medical Microbiology Laboratory, Department of Microbiology, Centre for Excellence in Life Sciences, Bharathidasan University, Tiruchirappalli, India
- Department of Neural Sciences, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, United States
- *Correspondence: Kalimuthusamy Natarajaseenivasan, ;
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Shetty A, Kundu S, Gomes-Solecki M. Inflammatory Signatures of Pathogenic and Non-Pathogenic Leptospira Infection in Susceptible C3H-HeJ Mice. Front Cell Infect Microbiol 2021; 11:677999. [PMID: 34249775 PMCID: PMC8264587 DOI: 10.3389/fcimb.2021.677999] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 05/25/2021] [Indexed: 12/17/2022] Open
Abstract
The exact global impact of leptospirosis is unknown due to inadequate surveillance systems in place in most low-income countries. In this study, we analyzed the differences in mouse inflammatory signatures involved in pathogenic versus non-pathogenic Leptospira recognition at 24h and 72h post infection. Injection of C3H-HeJ mice with non-pathogenic L. biflexa increased circulation of a few chemokines (5/21, 24%) without secretion of cytokines in blood that resulted in engagement of resident macrophages, dendritic cells, neutrophils and NK cells without engagement of T cells. In contrast, pathogenic L. interrogans induced circulation of a much higher panel of chemokines (18/21, 86%) and pro- and anti-inflammatory cytokines (11/19, 58%) in blood with a resulting signaling cascade leading to engagement of macrophages, dendritic cells, monocytes, NK cells and T cells without engagement of neutrophils. Although neutrophils do not appear to be engaged, a considerable number of chemokines that recruit other granulocytes such as eosinophils and basophils were also increased at 72h post infection with L. interrogans. Overall, the data suggest that prevention of dissemination of L. biflexa is associated with an early engagement of the innate immune response characterized by upregulation of a few chemokines that results in an efficacious phagocytic response without an overwhelming increase of pro-inflammatory cytokines. However, when macrophages fail to clear a pathogenic serovar such as L. interrogans, the adaptive response (T cells) is engaged to help out, but the resulting chemo-cytokine storm mediates a robust but non-resolving inflammatory response to pathogenic Leptospira that results in dissemination, kidney colonization, pathology and disease.
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Affiliation(s)
- Advait Shetty
- Department of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Suman Kundu
- Department of Microbiology, Immunology and Biochemistry, The University of Tennessee Health Science Center, Memphis, TN, United States
| | - Maria Gomes-Solecki
- Department of Pharmaceutical Sciences, The University of Tennessee Health Science Center, Memphis, TN, United States,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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Nair N, Gomes-Solecki M. A Mouse Model of Sublethal Leptospirosis: Protocols for Infection with Leptospira Through Natural Transmission Routes, for Monitoring Clinical and Molecular Scores of Disease, and for Evaluation of the Host Immune Response. CURRENT PROTOCOLS IN MICROBIOLOGY 2020; 59:e127. [PMID: 33141517 PMCID: PMC7643393 DOI: 10.1002/cpmc.127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Leptospirosis is a zoonotic disease caused by pathogenic Leptospira species that are maintained in sylvatic and domestic environments by transmission among rodents and other carriers. Humans become infected after contact of breached skin or mucosa with contaminated water or soil. Understanding persistent or sublethal infection in a host is critical for controlling human risk of exposure to pathogenic Leptospira. Animal models that recapitulate disease progression after infection via natural transmission routes are more appropriate for validation of vaccines and therapeutics. Furthermore, the ability to measure shedding of live Leptospira in urine of reservoir and carrier hosts can be used to develop new diagnostic assays and sensors to evaluate human risk of exposure. We developed inbred mouse models of Leptospirosis, that bypass survival as a criterion, in which we can analyze both pathogen and host factors affecting sublethal infection (<1 month), including shedding of Leptospira in urine. Mice are infected with pathogenic Leptospira using a physiologic route, and the clinical, histological, and molecular scores of disease are measured. Furthermore, the host immune response to Leptospira is evaluated. This mouse model also provides a tool in which to test fundamental hypotheses related to host-pathogen interactions and the immune mechanisms engaged in protective and pathogenic immune responses. © 2020 Wiley Periodicals LLC Basic Protocol 1: Culture and maintenance of virulent Leptospira Basic Protocol 2: Infection of mice through a physiologic route and collection of clinical scores and biological samples Basic Protocol 3: Analysis of pathogenesis after Leptospira infection.
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Affiliation(s)
- Nisha Nair
- Department of Microbiology, Immunology and Biochemistry, The University of Tennessee Health Science Center, Memphis, TN, USA
| | - Maria Gomes-Solecki
- Department of Microbiology, Immunology and Biochemistry, The University of Tennessee Health Science Center, Memphis, TN, USA
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5
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de Araújo Junior EC, Garcia LE, Araújo MJ, Oliveira-Junior IS, Arnold DR, Lopes FL, Marinho M. Gene expression is associated with virulence in murine macrophages infected with Leptospira spp. PLoS One 2019; 14:e0225272. [PMID: 31800570 PMCID: PMC6892507 DOI: 10.1371/journal.pone.0225272] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 10/31/2019] [Indexed: 11/25/2022] Open
Abstract
Leptospira genus contains species that affect human health with varying degrees of pathogenicity. In this context, we aimed to evaluate the differences in the modulation of host gene expression by strains of Leptospira varying in virulence. Our data showed a high number of differentially expressed transcripts in murine macrophages following 6h of infection. Leptospira infection modulated a set of genes independently of their degree of virulence. However, pathway analysis indicated that Apoptosis, ATM Signaling, and Cell Cycle: G2/M DNA Damage Checkpoint Regulation were exclusively regulated following infection with the virulent strain. Taken together, results demonstrated that species and virulence play a role during host response to Leptospira spp in murine macrophages, which could contribute to understanding the pathogenesis of leptospirosis.
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Affiliation(s)
- Erivelto Corrêa de Araújo Junior
- Department of Production and Animal Health, São Paulo State University (Unesp), School of Veterinary Medicine, Araçatuba, SP, Brazil
| | - Leandro Encarnação Garcia
- Department of Production and Animal Health, São Paulo State University (Unesp), School of Veterinary Medicine, Araçatuba, SP, Brazil
| | - Matheus Janeck Araújo
- Department of Production and Animal Health, São Paulo State University (Unesp), School of Veterinary Medicine, Araçatuba, SP, Brazil
| | - Itamar Souza Oliveira-Junior
- Department of Surgery, Discipline of Anesthesia, Pain and Intensive Medicine, Federal University of São Paulo, São Paulo, Brazil
| | - Daniel Robert Arnold
- Department of Production and Animal Health, São Paulo State University (Unesp), School of Veterinary Medicine, Araçatuba, SP, Brazil
| | - Flavia Lombardi Lopes
- Department of Production and Animal Health, São Paulo State University (Unesp), School of Veterinary Medicine, Araçatuba, SP, Brazil
| | - Márcia Marinho
- Department of Production and Animal Health, São Paulo State University (Unesp), School of Veterinary Medicine, Araçatuba, SP, Brazil
- * E-mail:
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6
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Werts C. Interaction of Leptospira with the Innate Immune System. Curr Top Microbiol Immunol 2019; 415:163-187. [PMID: 29038956 DOI: 10.1007/82_2017_46] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Innate immunity encompasses immediate host responses that detect and respond to microbes. Besides recognition by the complement system (see the chapter by A. Barbosa, this volume), innate immunity concerns cellular responses. These are triggered through recognition of conserved microbial components (called MAMPs) by pattern recognition receptors (PRRs), leading, through secretion of cytokines, antimicrobial peptides, and immune mediators, to cellular recruitment and phagocytosis. Leptospira spp. are successful zoonotic pathogenic bacteria that obviously overcome the immune system of their hosts. The first part of this chapter summarizes what is known about leptospires recognition and interaction with phagocytes and other innate immune cells, and the second part describes specific interactions of leptospiral MAMPs with PRRs from the TLR and NLR families. On the one hand, pathogenic leptospires appear to escape macrophage and neutrophil phagocytosis. On the other hand, studies about PRR sensing of leptospires remain very limited, but suggest that pathogenic leptospires escape some of the PRRs in a host-specific manner, due to peculiar cell wall specificities or post-translational modifications that may impair their recognition. Further studies are necessary to clarify the mechanisms and consequences of leptospiral escape on phagocytic functions and hopefully give clues to potential therapeutic strategies aimed at restoring the defective activation of PRRs by pathogenic Leptospira spp.
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Affiliation(s)
- Catherine Werts
- Unité Biologie et Génétique de La Paroi Bactérienne, Institut Pasteur, Paris, France.
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7
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de Castro ÍA, Bavia L, Fraga TR, Amano MT, Breda LCD, Granados-Martinez AP, da Silva AMG, Vasconcellos SA, Isaac L. Role of Murine Complement Component C5 in Acute in Vivo Infection by Pathogenic Leptospira interrogans. Front Cell Infect Microbiol 2018; 8:63. [PMID: 29568732 PMCID: PMC5852101 DOI: 10.3389/fcimb.2018.00063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 02/13/2018] [Indexed: 01/07/2023] Open
Abstract
Leptospirosis is considered one of the most important zoonosis worldwide. The activation of the Complement System is important to control dissemination of several pathogens in the host. Only a few studies have employed murine models to investigate leptospiral infection and our aim in this work was to investigate the role of murine C5 during in vivo infection, comparing wild type C57BL/6 (B6 C5+/+) and congenic C57BL/6 (B6 C5−/−, C5 deficient) mice during the first days of infection. All animals from both groups survived for at least 8 days post-infection with pathogenic Leptospira interrogans serovar Kennewicki strain Fromm (LPF). At the third day of infection, we observed greater numbers of LPF in the liver of B6 C5−/− mice when compared to B6 C5+/+ mice. Later, on the sixth day of infection, the LPF population fell to undetectable levels in the livers of both groups of mice. On the third day, the inflammatory score was higher in the liver of B6 C5+/+ mice than in B6 C5−/− mice, and returned to normal on the sixth day of infection in both groups. No significant histopathological differences were observed in the lung, kidney and spleen from both infected B6 C5+/+ than B6 C5−/− mice. Likewise, the total number of circulating leukocytes was not affected by the absence of C5. The liver levels of IL-10 on the sixth day of infection was lower in the absence of C5 when compared to wild type mice. No significant differences were observed in the levels of several inflammatory cytokines when B6 C5+/+ and B6 C5−/− were compared. In conclusion, C5 may contribute to the direct killing of LPF in the first days of infection in C57BL/6 mice. On the other hand, other effector immune mechanisms probably compensate Complement impairment since the mice survival was not affected by the absence of C5 and its activated fragments, at least in the early stage of this infection.
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Affiliation(s)
- Íris A de Castro
- Laboratory of Complement, Department of Immunology, University of São Paulo, São Paulo, Brazil
| | - Lorena Bavia
- Laboratory of Complement, Department of Immunology, University of São Paulo, São Paulo, Brazil
| | - Tatiana R Fraga
- Laboratory of Complement, Department of Immunology, University of São Paulo, São Paulo, Brazil
| | - Mariane T Amano
- Laboratory of Complement, Department of Immunology, University of São Paulo, São Paulo, Brazil
| | - Leandro C D Breda
- Laboratory of Complement, Department of Immunology, University of São Paulo, São Paulo, Brazil
| | | | - Ana M G da Silva
- Institute of Tropical Medicine, University of São Paulo, São Paulo, Brazil
| | | | - Lourdes Isaac
- Laboratory of Complement, Department of Immunology, University of São Paulo, São Paulo, Brazil
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Thirumalairaj J, Sivasankari K, Natarajaseenivasan K, Balagurunathan R. Potential anti-leptospiral compound, leptomycin B from marine Streptomyces indiaensis MSU5: taxonomy, fermentation, compound isolation, in vitro and in vivo efficacy. World J Microbiol Biotechnol 2017; 33:187. [PMID: 28956236 DOI: 10.1007/s11274-017-2351-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 09/21/2017] [Indexed: 11/30/2022]
Abstract
Leptospirosis is a worldwide reemerging tropical zoonotic disease with symptoms of mild febrile illness to more severe multiple organ failure caused by pathogenic leptospiral strains. There was no effective antibiotic for treating leptospirosis. Here, the anti-leptospiral potential of marine actinobacterial compound from Streptomyces indiaensis MSU5 isolated from Manakudy marine sediment, Tamil Nadu, India was evaluated. The potential actinobacterial strain was identified by phenotypic, cell wall, 16S rRNA gene sequence and phylogenetic analysis. In vitro anti-leptospiral activity of the actinobacterial compound was determined using broth microdilution test against various serovars of Leptospira with different concentration ranging from 15.625 to 500 µg/ml. Mass production of anti-leptospiral compound was carried out in agar surface fermentation with optimized condition and purified by preparative TLC. The purified fraction of anti-leptospiral compound named as MSU5-1, and it was confirmed by microdilution test. Remarkably, the compound MSU5-1 showed minimum inhibitory concentration of 62.5 µg/ml and minimum bactericidal concentration of 125 µg/ml against human pathogenic leptospiral isolate strain N2. The structural elucidation of purified compound was carried out using UV, FT-IR, NMR and LC-MS analysis. The compound MSU5-1 was tentatively identified as leptomycin B (C33H48O6) with molecular weight 541.1 g/mol. Anti-leptospiral activity of compound MSU5-1 exhibited 80% of survival rate in mice model, further it was confirmed by Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) analysis. From the available literature, this is the first report on the marine actinobacterial compound for evaluating both in vitro and in vivo leptospiricidal activity.
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Affiliation(s)
- Jeyaraman Thirumalairaj
- Actinobacterial Research Laboratory, Department of Microbiology, Periyar University, Salem, Tamil Nadu, 636 011, India
| | - Karikalacholan Sivasankari
- Medical Microbiology Laboratory, Department of Microbiology, Bharathidasan University, Tiruchirappalli, Tamil Nadu, 620 024, India
| | - Kalimuthusamy Natarajaseenivasan
- Medical Microbiology Laboratory, Department of Microbiology, Bharathidasan University, Tiruchirappalli, Tamil Nadu, 620 024, India
| | - Ramasamy Balagurunathan
- Actinobacterial Research Laboratory, Department of Microbiology, Periyar University, Salem, Tamil Nadu, 636 011, India.
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Gomes-Solecki M, Santecchia I, Werts C. Animal Models of Leptospirosis: Of Mice and Hamsters. Front Immunol 2017; 8:58. [PMID: 28270811 PMCID: PMC5318464 DOI: 10.3389/fimmu.2017.00058] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 01/16/2017] [Indexed: 01/27/2023] Open
Abstract
Pathogenic Leptospira sp. are spirochetal bacteria responsible for leptospirosis, an emerging worldwide zoonosis. These spirochetes are very successful pathogens that infect a wide range of hosts such as fish, reptiles, birds, marsupials, and mammals. Transmission occurs when chronically infected animals excrete live bacteria in their urine, contaminating the environment. Leptospira sp. enter their hosts through damaged skin and mucosa. Chronically infected rats and mice are asymptomatic and are considered as important reservoirs of the disease. Infected humans may develop either a flu-like, usually mild illness with or without chronic asymptotic renal colonization, or a severe acute disease with kidney, liver, and heart failure, potentially leading to death. Leptospirosis is an economic burden on society due to health-care costs related to elevated morbidity of humans and loss of animals of agricultural interest. There are no effective vaccines against leptospirosis. Leptospira sp. are difficult to genetically manipulate which delays the pace of research progress. In this review, we discuss in an historical perspective how animal models have contributed to further our knowledge of leptospirosis. Hamsters, guinea pigs, and gerbils have been instrumental to study the pathophysiology of acute lethal leptospirosis and the Leptospira sp. genes involved in virulence. Chronic renal colonization has been mostly studied using experimentally infected rats. A special emphasis will be placed on mouse models, long thought to be irrelevant since they survive lethal infection. However, mice have recently been shown to be good models of sublethal infection leading to chronic colonization. Furthermore, congenic and transgenic mice have proven essential to study how innate immune cells interact with the pathogen and to understand the role of the toll-like receptor 4, which is important to control Leptospira sp. load and disease. The use of inbred and transgenic mouse models opens up the field to the comprehensive study of immune responses to Leptospira sp. infection and subsequent pathophysiology of inflammation. It also allows for testing of drugs and vaccines in a biological system that can avail of a wealth of molecular tools that enable understanding of the mechanisms of action of protective vaccines.
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Affiliation(s)
- Maria Gomes-Solecki
- Department of Microbiology, Immunology and Biochemistry, The University of Tennessee Health Science Center , Memphis, TN , USA
| | - Ignacio Santecchia
- Institut Pasteur, Unité Biologie et Génétique de la Paroi Bactérienne, Paris, France; INSERM, équipe Avenir, Paris, France
| | - Catherine Werts
- Institut Pasteur, Unité Biologie et Génétique de la Paroi Bactérienne, Paris, France; INSERM, équipe Avenir, Paris, France
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10
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Lessa-Aquino C, Lindow JC, Randall A, Wunder E, Pablo J, Nakajima R, Jasinskas A, Cruz JS, Damião AO, Nery N, Ribeiro GS, Costa F, Hagan JE, Reis MG, Ko AI, Medeiros MA, Felgner PL. Distinct antibody responses of patients with mild and severe leptospirosis determined by whole proteome microarray analysis. PLoS Negl Trop Dis 2017; 11:e0005349. [PMID: 28141801 PMCID: PMC5302828 DOI: 10.1371/journal.pntd.0005349] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 02/10/2017] [Accepted: 01/22/2017] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND Leptospirosis is an important zoonotic disease worldwide. Humans usually present a mild non-specific febrile illness, but a proportion of them develop more severe outcomes, such as multi-organ failure, lung hemorrhage and death. Such complications are thought to depend on several factors, including the host immunity. Protective immunity is associated with humoral immune response, but little is known about the immune response mounted during naturally-acquired Leptospira infection. METHODS AND PRINCIPAL FINDINGS Here, we used protein microarray chip to profile the antibody responses of patients with severe and mild leptospirosis against the complete Leptospira interrogans serovar Copenhageni predicted ORFeome. We discovered a limited number of immunodominant antigens, with 36 antigens specific to patients, of which 11 were potential serodiagnostic antigens, identified at acute phase, and 33 were potential subunit vaccine targets, detected after recovery. Moreover, we found distinct antibody profiles in patients with different clinical outcomes: in the severe group, overall IgM responses do not change and IgG responses increase over time, while both IgM and IgG responses remain stable in the mild patient group. Analyses of individual patients' responses showed that >74% of patients in the severe group had significant IgG increases over time compared to 29% of patients in the mild group. Additionally, 90% of IgM responses did not change over time in the mild group, compared to ~51% in the severe group. CONCLUSIONS In the present study, we detected antibody profiles associated with disease severity and speculate that patients with mild disease were protected from severe outcomes due to pre-existing antibodies, while patients with severe leptospirosis demonstrated an antibody profile typical of first exposure. Our findings represent a significant advance in the understanding of the humoral immune response to Leptospira infection, and we have identified new targets for the development of subunit vaccines and diagnostic tests.
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Affiliation(s)
| | - Janet C. Lindow
- Fiocruz, Gonçalo Moniz Research Institute, Brazilian Ministry of Health, Salvador, BA, Brazil
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States of America
| | - Arlo Randall
- Antigen Discovery Inc, Irvine, CA, United States of America
| | - Elsio Wunder
- Fiocruz, Gonçalo Moniz Research Institute, Brazilian Ministry of Health, Salvador, BA, Brazil
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States of America
| | - Jozelyn Pablo
- Department of Medicine, Division of Infectious Disease, University of California Irvine, Irvine, California, United States of America
| | - Rie Nakajima
- Department of Medicine, Division of Infectious Disease, University of California Irvine, Irvine, California, United States of America
| | - Algis Jasinskas
- Department of Medicine, Division of Infectious Disease, University of California Irvine, Irvine, California, United States of America
| | - Jaqueline S. Cruz
- Fiocruz, Gonçalo Moniz Research Institute, Brazilian Ministry of Health, Salvador, BA, Brazil
| | - Alcineia O. Damião
- Fiocruz, Gonçalo Moniz Research Institute, Brazilian Ministry of Health, Salvador, BA, Brazil
| | - Nívison Nery
- Fiocruz, Gonçalo Moniz Research Institute, Brazilian Ministry of Health, Salvador, BA, Brazil
| | - Guilherme S. Ribeiro
- Institute of Collective Health, Federal University of Bahia, Salvador, BA, Brazil
| | - Federico Costa
- Fiocruz, Gonçalo Moniz Research Institute, Brazilian Ministry of Health, Salvador, BA, Brazil
- Institute of Collective Health, Federal University of Bahia, Salvador, BA, Brazil
| | - José E. Hagan
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States of America
| | - Mitermayer Galvão Reis
- Fiocruz, Gonçalo Moniz Research Institute, Brazilian Ministry of Health, Salvador, BA, Brazil
| | - Albert I. Ko
- Fiocruz, Gonçalo Moniz Research Institute, Brazilian Ministry of Health, Salvador, BA, Brazil
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States of America
| | | | - Philip L. Felgner
- Department of Medicine, Division of Infectious Disease, University of California Irvine, Irvine, California, United States of America
- * E-mail:
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Ilangovan A, Sakthivel P, Sivasankari K, Mercy CSA, Natarajaseenivasan K. Discovery of 6,7-dihydro-3H-pyrano[4,3-c]isoxazol-3-ones as a new class of pathogen specific anti-leptospiral agents. Eur J Med Chem 2017; 125:29-40. [PMID: 27643561 DOI: 10.1016/j.ejmech.2016.09.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 09/06/2016] [Accepted: 09/07/2016] [Indexed: 11/30/2022]
Abstract
A simple and efficient method for the synthesis of a series of 6,7-dihydro-3H-pyrano[4,3-c]isoxazol-3-one derivatives starting from 5-carboalkoxy-2,3-dihydropyranone (5-CDHPs) has been developed. Pyranoisoxazolones 10a-j, dihydronaphthopyran-4-one (DHNPs) class of natural product 12b and 12c and its analogues 12a and 13a-c were preliminarily screened against pathogenic leptospiral serovar Autumnalis strain N2 at various concentrations. Six pyranoisoxazolones, 10b, 10d, 10f, 10g, 10i and 10j which displayed very good anti-leptospiral activity was taken for secondary screening against twelve strains of pathogenic and one non-pathogenic leptospiral serovars. While all the compounds displayed significant anti-leptospiral activity against the pathogenic serovars at MIC of 62.5-500 μg/mL. Compounds 10d, 10g and 10j did not show any significant effect on non-pathogenic serovar. Inhibition of leptospires at a significant level by pyranoisoxazolone 10g was confirmed using RT-qPCR assay. In vivo treatment of BALB/c mice with compound 10g revealed that, it has 95% survivability against the pathogenic strain Canicola and also showed inhibition of renal colonization of leptospires. Compound 10g was found to show cytotoxicity against THP-1 cells only at higher concentration (≥75 μg/mL). Effective binding of compound 10g with leptospiral outer membrane protein LipL32 observed via in silico molecular docking provided a suitable explanation for pathogen specificity of compound 10g. Antibiotics acting against leptospirosis in human are very few. The results obtained from in vitro, in vivo and in silico study reveals that 6,7-dihydro-3H-pyrano[4,3-c]isoxazol-3-ones class of compounds are lead molecules for further development as pathogen specific anti-leptospiral agents.
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Affiliation(s)
- Andivelu Ilangovan
- School of Chemistry, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu, India.
| | - Palaniappan Sakthivel
- School of Chemistry, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu, India
| | - Karikalacholan Sivasankari
- Medical Microbiology Laboratory, Department of Microbiology, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu, 620024, India
| | - Charles Solomon Akino Mercy
- Medical Microbiology Laboratory, Department of Microbiology, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu, 620024, India
| | - Kalimuthusamy Natarajaseenivasan
- Medical Microbiology Laboratory, Department of Microbiology, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu, 620024, India
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Real-Time PCR Reveals Rapid Dissemination of Leptospira interrogans after Intraperitoneal and Conjunctival Inoculation of Hamsters. Infect Immun 2016; 84:2105-2115. [PMID: 27141082 DOI: 10.1128/iai.00094-16] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2016] [Accepted: 04/27/2016] [Indexed: 01/06/2023] Open
Abstract
The pathogen Leptospira interrogans is a highly motile spirochete that causes acute and fulminant infections in humans and other accidental hosts. Hematogenous dissemination is important for infection by the pathogen but remains poorly understood because few animal model studies have used sensitive tools to quantify the bacteria. We evaluated the kinetics of leptospiral infection in Golden Syrian hamsters by a sensitive quantitative real-time PCR (TaqMan) with lipl32 as the target gene. The dissemination and bacterial burden were measured after intraperitoneal infection with a high dose (10(8)) or low dose (2.5 × 10(2)) of leptospires. We also examined the conjunctival challenge route to mimic the natural history of infection. Quantification of leptospires in perfused animals revealed that pathogens were detected in all organs of intraperitoneally infected hamsters, including the eye and brain, within 1 h after inoculation of 10(8) virulent L. interrogans bacteria. Peaks of 10(5) to 10(8) leptospires per gram or per milliliter were achieved in blood and all tissues between day 4 and day 8 after intraperitoneal inoculation of high- and low-dose challenges, respectively, coinciding with macroscopic and histological changes. The conjunctival route resulted in a delay in the time to peak organ burden in comparison to intraperitoneal infection, indicating that although infection could be established, penetration efficiency was low across this epithelial barrier. Surprisingly, infection with a large inoculum of high-passage-number attenuated L. interrogans strains resulted in dissemination to all organs in the first 4 days postinfection, albeit with a lower burden, followed by clearance from the blood and organs 7 days postinfection and survival of all animals. These results demonstrate that leptospiral dissemination and tissue invasion occur. In contrast, development of a critical level of tissue burden and pathology are dependent on the virulence of the infecting strain.
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Mouse model for sublethal Leptospira interrogans infection. Infect Immun 2015; 83:4693-700. [PMID: 26416909 DOI: 10.1128/iai.01115-15] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 09/15/2015] [Indexed: 01/24/2023] Open
Abstract
Although Leptospira can infect a wide range of mammalian species, most studies have been conducted in golden Syrian hamsters, a species particularly sensitive to acute disease. Chronic disease has been well characterized in the rat, one of the natural reservoir hosts. Studies in another asymptomatic reservoir host, the mouse, have occasionally been done and have limited infection to mice younger than 6 weeks of age. We analyzed the outcome of sublethal infection of C3H/HeJ mice older than age 10 weeks with Leptospira interrogans serovar Copenhageni. Infection led to bloodstream dissemination of Leptospira, which was followed by urinary shedding, body weight loss, hypothermia, and colonization of the kidney by live spirochetes 2 weeks after infection. In addition, Leptospira dissemination triggered inflammation in the kidney but not in the liver or lung, as determined by increased levels of mRNA transcripts for the keratinocyte-derived chemokine, RANTES, macrophage inflammatory protein 2, tumor necrosis factor alpha, interleukin-1β, inducible nitric oxide synthase, interleukin-6, and gamma interferon in kidney tissue. The acquired humoral response to Leptospira infection led to the production of IgG mainly of the IgG1 subtype. Flow cytometric analysis of splenocytes from infected mice revealed that cellular expansion was primarily due to an increase in the levels of CD4(+) and double-negative T cells (not CD8(+) cells) and that CD4(+) T cells acquired a CD44(high) CD62L(low) effector phenotype not accompanied by increases in memory T cells. A mouse model for sublethal Leptospira infection allows understanding of the bacterial and host factors that lead to immune evasion, which can result in acute or chronic disease or resistance to infection (protection).
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Abstract
Pathogenic Leptospira has the capacity to infect a broad range of mammalian hosts. Leptospirosis may appear as an acute, potentially fatal infection in accidental hosts, or progress into a chronic, largely asymptomatic infection in natural maintenance hosts. The course that Leptospira infection follows is dependent upon poorly understood factors, but is heavily influenced by both the host species and bacterial serovar involved in infection. Recognition of pathogen-associated molecular patterns (PAMPs) by a variety of host pattern recognition receptors (PRRs) activates the host immune system. The outcome of this response may result in bacterial clearance, limited bacterial colonization of a few target organs, principally the kidney, or induction of sepsis as the host succumbs to infection and dies. This chapter describes current knowledge of how the host recognizes Leptospira and responds to infection using innate and acquired immune responses. Aspects of immune-mediated pathology and pathogen strategies to evade the host immune response are also addressed.
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Affiliation(s)
- Richard L Zuerner
- Department of Biomedical Sciences and Veterinary Public Health, Swedish University for Agricultural Sciences, 75007, Uppsala, Sweden,
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Decay-accelerating factor 1 deficiency exacerbates leptospiral-induced murine chronic nephritis and renal fibrosis. PLoS One 2014; 9:e102860. [PMID: 25032961 PMCID: PMC4102560 DOI: 10.1371/journal.pone.0102860] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Accepted: 06/24/2014] [Indexed: 01/27/2023] Open
Abstract
Leptospirosis is a global zoonosis caused by pathogenic Leptospira, which can colonize the proximal renal tubules and persist for long periods in the kidneys of infected hosts. Here, we characterized the infection of C57BL/6J wild-type and Daf1−/− mice, which have an enhanced host response, with a virulent Leptospira interrogans strain at 14 days post-infection, its persistence in the kidney, and its link to kidney fibrosis at 90 days post-infection. We found that Leptospira interrogans can induce acute moderate nephritis in wild-type mice and is able to persist in some animals, inducing fibrosis in the absence of mortality. In contrast, Daf1−/− mice showed acute mortality, with a higher bacterial burden. At the chronic stage, Daf1−/− mice showed greater inflammation and fibrosis than at 14 days post-infection and higher levels at all times than the wild-type counterpart. Compared with uninfected mice, infected wild-type mice showed higher levels of IL-4, IL-10 and IL-13, with similar levels of α-smooth muscle actin, galectin-3, TGF-β1, IL-17, IFN-γ, and lower IL-12 levels at 90 days post-infection. In contrast, fibrosis in Daf1−/− mice was accompanied by high expression of α-smooth muscle actin, galectin-3, IL-10, IL-13, and IFN-γ, similar levels of TGF-β1, IL-12, and IL-17 and lower IL-4 levels. This study demonstrates the link between Leptospira-induced murine chronic nephritis with renal fibrosis and shows a protective role of Daf1.
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Gene expression profiles of immune mediators and histopathological findings in animal models of leptospirosis: comparison between susceptible hamsters and resistant mice. Infect Immun 2011; 79:4480-92. [PMID: 21844232 DOI: 10.1128/iai.05727-11] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Leptospirosis is a widespread zoonosis characterized by multiple organ failure and variable host susceptibility toward pathogenic Leptospira strains. In this study, we put the role of inflammatory mediators in parallel with bacterial burdens and organ lesions by comparing a susceptible animal model, the hamster, and a resistant one, the Oncins France 1 (OF1) mouse, both infected with virulent Leptospira interrogans serovar Icterohaemorrhagiae strain Verdun. Histological observations evidenced edema, congestion, hemorrhage, and inflammatory infiltration in the organs of hamsters, in contrast to limited changes in mice. Using reverse transcription-quantitative PCR techniques, we showed that the relative Leptospira burden progressively increased in hamster tissues, while a rapid clearance was observed in mouse tissues. The early regulation of the proinflammatory mediators interleukin-1β (IL-1β), IL-6, tumor necrosis factor alpha, and cyclo-oxygenase-2 and the chemokines gamma interferon-inducible protein 10 kDa/CXCL10 and macrophage inflammatory protein-1α/CCL3 in mouse tissues contrasted with their delayed and massive overexpression in hamster tissues. Conversely, the induction of the anti-inflammatory cytokine IL-10 was faster in the resistant than in the susceptible animal model. The role of these cytokines in the pathophysiology of leptospirosis and the implications of their differential regulation in the development of this disease are discussed.
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Haanwinckel MCS, de Oliveira SL. Production of reactive oxygen (H2O2) and nitrogen (NO) intermediates and tnf-α in mice genetically selected for high (H) and low (L) antibody response and experimentally infected with Leptospira serovar pomona. Braz J Microbiol 2011; 42:729-39. [PMID: 24031688 PMCID: PMC3769827 DOI: 10.1590/s1517-838220110002000041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 05/24/2010] [Accepted: 01/13/2011] [Indexed: 11/30/2022] Open
Abstract
The aim of the present study was to evaluate the activity of macrophages, and the production of TNF-α and antibodies against experimental infection by Leptospira serovar Pomona in mice genetically selected for High (H) or Low (L) humoral immune response. To evaluate macrophagic activity, peritoneal and splenic lavages were performed for determination of oxygen (H2O2) and nitrogen (NO) intermediates. The production of the tumor necrosis factor (TNF-α) was investigated through bioassays in serum and homogenates of splenic and hepatic cells of control and infected animals, as was as specific antibodies production. The immune response against serovar Pomona in those lines, was characterized by high antibody production, especially in later periods of the infectious process, whereas values of bacterial recovery in culture medium were lower. The production of reactives oxygen and nitrogen intermediate, also helped to eliminate Leptospira Pomona in both lines; H2O2 production an important factor in HIV-A, as well as NO production in LIV-A, especially in later post-inoculation periods. The same was detected for TNF-α. Results suggest that such lines could be an important model to investigate the pathogenesis and the immune response of animals against the several Leptospira serovars.
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Affiliation(s)
- Maria Cristina Santos Haanwinckel
- Departamento de Microbiologia-Imunologia, Instituto de Biociências, Universidade Estadual Paulista , Botucatu, SP , Brasil; ; Departamento de Doenças Tropicais e Diagnóstico por Imagem, Faculdade de Medicina, Universidade Estadual Paulista , Botucatu, SP , Brasil
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Srikram A, Zhang K, Bartpho T, Lo M, Hoke DE, Sermswan RW, Adler B, Murray GL. Cross-protective immunity against leptospirosis elicited by a live, attenuated lipopolysaccharide mutant. J Infect Dis 2011; 203:870-9. [PMID: 21220775 DOI: 10.1093/infdis/jiq127] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Leptospira species cause leptospirosis, a zoonotic disease found worldwide. Current vaccines against leptospirosis provide protection only against closely related serovars. METHODS We evaluated an attenuated transposon mutant of Leptospira interrogans serovar Manilae (M1352, defective in lipopolysaccharide biosynthesis) as a live vaccine against leptospirosis. Hamsters received a single dose of vaccine and were challenged with the homologous serovar (Manilae) and a serologically unrelated heterologous serovar (Pomona). Comparisons were made with killed vaccines. Potential cross-protective antigens against leptospirosis were investigated. RESULTS Live M1352 vaccine induced superior protection in hamsters against homologous challenge. The live vaccine also stimulated cross-protection against heterologous challenge, with 100% survival (live M1352) versus 40% survival (killed vaccine). Hamsters receiving either vaccine responded to the dominant membrane proteins LipL32 and LipL41. Hamsters receiving the live vaccine additionally recognized LA3961/OmpL36 (unknown function), Loa22 (OmpA family protein, recognized virulence factor), LA2372 (general secretory protein G), and LA1939 (hypothetical protein). Manilae LigA was recognized by M1352 vaccinates, whereas LipL36 was detected in Pomona. CONCLUSION This study demonstrated that a live, attenuated vaccine can stimulate cross-protective immunity to L. interrogans and has identified antigens that potentially confer cross-protection against leptospirosis.
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Affiliation(s)
- Amporn Srikram
- Faculty of Medicine, Melioidosis Research Center, Khon Kaen University, Khon Kaen, Thailand
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Transcriptional response of Leptospira interrogans to iron limitation and characterization of a PerR homolog. Infect Immun 2010; 78:4850-9. [PMID: 20805337 DOI: 10.1128/iai.00435-10] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Leptospirosis is a globally significant zoonosis caused by Leptospira spp. Iron is essential for growth of most bacterial species. Since iron availability is low in the host, pathogens have evolved complex iron acquisition mechanisms to survive and establish infection. In many bacteria, expression of iron uptake and storage proteins is regulated by Fur. L. interrogans encodes four predicted Fur homologs; we have constructed a mutation in one of these, la1857. We conducted microarray analysis to identify iron-responsive genes and to study the effects of la1857 mutation on gene expression. Under iron-limiting conditions, 43 genes were upregulated and 49 genes were downregulated in the wild type. Genes encoding proteins with predicted involvement in inorganic ion transport and metabolism (including TonB-dependent proteins and outer membrane transport proteins) were overrepresented in the upregulated list, while 54% of differentially expressed genes had no known function. There were 16 upregulated genes of unknown function which are absent from the saprophyte L. biflexa and which therefore may encode virulence-associated factors. Expression of iron-responsive genes was not significantly affected by mutagenesis of la1857, indicating that LA1857 is not a global regulator of iron homeostasis. Upregulation of heme biosynthetic genes and a putative catalase in the mutant suggested that LA1857 is more similar to PerR, a regulator of the oxidative stress response. Indeed, the la1857 mutant was more resistant to peroxide stress than the wild type. Our results provide insights into the role of iron in leptospiral metabolism and regulation of the oxidative stress response, including genes likely to be important for virulence.
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Lo M, Cordwell SJ, Bulach DM, Adler B. Comparative transcriptional and translational analysis of leptospiral outer membrane protein expression in response to temperature. PLoS Negl Trop Dis 2009; 3:e560. [PMID: 19997626 PMCID: PMC2780356 DOI: 10.1371/journal.pntd.0000560] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Accepted: 10/28/2009] [Indexed: 11/19/2022] Open
Abstract
Background Leptospirosis is a global zoonosis affecting millions of people annually. Transcriptional changes in response to temperature were previously investigated using microarrays to identify genes potentially expressed upon host entry. Past studies found that various leptospiral outer membrane proteins are differentially expressed at different temperatures. However, our microarray studies highlighted a divergence between protein abundance and transcript levels for some proteins. Given the abundance of post-transcriptional expression control mechanisms, this finding highlighted the importance of global protein analysis systems. Methodology/Principal Findings To complement our previous transcription study, we evaluated differences in the proteins of the leptospiral outer membrane fraction in response to temperature upshift. Outer membrane protein-enriched fractions from Leptospira interrogans grown at 30°C or overnight upshift to 37°C were isolated and the relative abundance of each protein was determined by iTRAQ analysis coupled with two-dimensional liquid chromatography and tandem mass spectrometry (2-DLC/MS-MS). We identified 1026 proteins with 99% confidence; 27 and 66 were present at elevated and reduced abundance respectively. Protein abundance changes were compared with transcriptional differences determined from the microarray studies. While there was some correlation between the microarray and iTRAQ data, a subset of genes that showed no differential expression by microarray was found to encode temperature-regulated proteins. This set of genes is of particular interest as it is likely that regulation of their expression occurs post-transcriptionally, providing an opportunity to develop hypotheses about the molecular dynamics of the outer membrane of Leptospira in response to changing environments. Conclusions/Significance This is the first study to compare transcriptional and translational responses to temperature shift in L. interrogans. The results thus provide an insight into the mechanisms used by L. interrogans to adapt to conditions encountered in the host and to cause disease. Our results suggest down-regulation of protein expression in response to temperature, and decreased expression of outer membrane proteins may facilitate minimal interaction with host immune mechanisms. Leptospirosis, caused by Leptospira spp., is a disease of worldwide significance affecting millions of people annually. Bacteria of this species are spread by various carrier animals, including rodents and domestic livestock, which shed the leptospires via their urine into the environment. Humans become infected through direct contact with carrier animals or indirectly via contaminated water or soil. Temperature is a key trigger used by many bacteria to sense changes in environmental conditions, including entry from the environment into the host. This study was the first comprehensive research into changes occurring in the outer membrane of Leptospira in response to temperature and how these changes correlate with gene expression changes. An understanding of the regulation and function of these proteins is important as they may provide an adaptation and survival advantage for the microorganism which may enhance its ability to infect hosts and cause disease. Our data suggest regulation of proteins in the outer membrane which may possibly be a mechanism to minimise interactions with the host immune response.
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Affiliation(s)
- Miranda Lo
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Department of Microbiology, Monash University, Melbourne, Australia
| | - Stuart J. Cordwell
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Department of Microbiology, Monash University, Melbourne, Australia
- School of Molecular and Microbial Biosciences, University of Sydney, Sydney, Australia
| | - Dieter M. Bulach
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Department of Microbiology, Monash University, Melbourne, Australia
- Victorian Bioinformatics Consortium, Monash University, Melbourne. Australia
| | - Ben Adler
- Australian Research Council Centre of Excellence in Structural and Functional Microbial Genomics, Department of Microbiology, Monash University, Melbourne, Australia
- Victorian Bioinformatics Consortium, Monash University, Melbourne. Australia
- * E-mail: .
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Chassin C, Picardeau M, Goujon JM, Bourhy P, Quellard N, Darche S, Badell E, d'Andon MF, Winter N, Lacroix-Lamandé S, Buzoni-Gatel D, Vandewalle A, Werts C. TLR4- and TLR2-Mediated B Cell Responses Control the Clearance of the Bacterial Pathogen,Leptospira interrogans. THE JOURNAL OF IMMUNOLOGY 2009; 183:2669-77. [DOI: 10.4049/jimmunol.0900506] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Silva ÉF, Medeiros MA, McBride AJA, Matsunaga J, Esteves GS, Ramos JGR, Santos CS, Croda J, Homma A, Dellagostin OA, Haake DA, Reis MG, Ko AI. The terminal portion of leptospiral immunoglobulin-like protein LigA confers protective immunity against lethal infection in the hamster model of leptospirosis. Vaccine 2007; 25:6277-86. [PMID: 17629368 PMCID: PMC1994161 DOI: 10.1016/j.vaccine.2007.05.053] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2007] [Revised: 05/15/2007] [Accepted: 05/23/2007] [Indexed: 10/23/2022]
Abstract
Subunit vaccines are a potential intervention strategy against leptospirosis, which is a major public health problem in developing countries and a veterinary disease in livestock and companion animals worldwide. Leptospiral immunoglobulin-like (Lig) proteins are a family of surface-exposed determinants that have Ig-like repeat domains found in virulence factors such as intimin and invasin. We expressed fragments of the repeat domain regions of LigA and LigB from Leptospira interrogans serovar Copenhageni. Immunization of Golden Syrian hamsters with Lig fragments in Freund's adjuvant induced robust antibody responses against recombinant protein and native protein, as detected by ELISA and immunoblot, respectively. A single fragment, LigANI, which corresponds to the six carboxy-terminal Ig-like repeat domains of the LigA molecule, conferred immunoprotection against mortality (67-100%, P<0.05) in hamsters which received a lethal inoculum of L. interrogans serovar Copenhageni. However, immunization with this fragment did not confer sterilizing immunity. These findings indicate that the carboxy-terminal portion of LigA is an immunoprotective domain and may serve as a vaccine candidate for human and veterinary leptospirosis.
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Affiliation(s)
- Éverton F. Silva
- Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Brazil
- Biotechnology Centre, Federal University of Pelotas, Pelotas, Brazil
| | - Marco A. Medeiros
- Bio-Manguinhos, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Rio de Janeiro, Brazil
| | - Alan J. A. McBride
- Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Brazil
| | - Jim Matsunaga
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California
- Department of Medicine, the David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Gabriela S. Esteves
- Bio-Manguinhos, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Rio de Janeiro, Brazil
| | - João G. R. Ramos
- Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Brazil
| | - Cleiton S. Santos
- Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Brazil
| | - Júlio Croda
- Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Brazil
| | - Akira Homma
- Bio-Manguinhos, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Rio de Janeiro, Brazil
| | | | - David A. Haake
- Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California
- Department of Medicine, the David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Mitermayer G. Reis
- Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Brazil
| | - Albert I. Ko
- Gonçalo Moniz Research Center, Oswaldo Cruz Foundation, Brazilian Ministry of Health, Salvador, Brazil
- Division of International Medicine and Infectious Disease, Weill Medical College of Cornell University, New York, USA
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Lo M, Bulach DM, Powell DR, Haake DA, Matsunaga J, Paustian ML, Zuerner RL, Adler B. Effects of temperature on gene expression patterns in Leptospira interrogans serovar Lai as assessed by whole-genome microarrays. Infect Immun 2006; 74:5848-59. [PMID: 16988264 PMCID: PMC1594916 DOI: 10.1128/iai.00755-06] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Leptospirosis is an important zoonosis of worldwide distribution. Humans become infected via exposure to pathogenic Leptospira spp. from infected animals or contaminated water or soil. The availability of genome sequences for Leptospira interrogans, serovars Lai and Copenhageni, has opened up opportunities to examine global transcription profiles using microarray technology. Temperature is a key environmental factor known to affect leptospiral protein expression. Leptospira spp. can grow in artificial media at a range of temperatures reflecting conditions found in the environment and the mammalian host. Therefore, transcriptional changes were compared between cultures grown at 20 degrees C, 30 degrees C, 37 degrees C, and 39 degrees C to represent ambient temperatures in the environment, growth under laboratory conditions, and temperatures in healthy and febrile hosts. Data from direct pairwise comparisons of the four temperatures were consolidated to examine transcriptional changes at two generalized biological conditions representing mammalian physiological temperatures (37 degrees C and 39 degrees C) versus environmental temperatures (20 degrees C and 30 degrees C). Additionally, cultures grown at 30 degrees C then shifted overnight to 37 degrees C were compared with those grown long-term at 30 degrees C and 37 degrees C to identify genes potentially expressed in the early stages of infection. Comparison of data sets from physiological versus environmental experiments with upshift experiments provided novel insights into possible transcriptional changes at different stages of infection. Changes included differential expression of chemotaxis and motility genes, signal transduction systems, and genes encoding proteins involved in alteration of the outer membrane. These findings indicate that temperature is an important factor regulating expression of proteins that facilitate invasion and establishment of disease.
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Affiliation(s)
- Miranda Lo
- Department of Microbiology, Monash University, Victoria 3800, Australia
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Palaniappan RUM, McDonough SP, Divers TJ, Chen CS, Pan MJ, Matsumoto M, Chang YF. Immunoprotection of recombinant leptospiral immunoglobulin-like protein A against Leptospira interrogans serovar Pomona infection. Infect Immun 2006; 74:1745-50. [PMID: 16495547 PMCID: PMC1418682 DOI: 10.1128/iai.74.3.1745-1750.2006] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We previously reported the cloning and characterization of leptospiral immunoglobulin-like proteins LigA and LigB of Leptospira interrogans. LigA and LigB are conserved at the amino-terminal region but are variable at the carboxyl-terminal region. Here, we evaluate the potential of recombinant LigA (rLigA) as a vaccine candidate against infection by L. interrogans serovar Pomona in a hamster model. rLigA was truncated into conserved (rLigAcon) and variable (rLigAvar) regions and expressed in Escherichia coli as a fusion protein with glutathione-S-transferase (rLigA). Golden Syrian hamsters were immunized at 3 and 6 weeks of age with rLigA (rLigAcon and rLigAvar) with aluminum hydroxide as an adjuvant. Hamsters given recombinant glutathione-S-transferase (rGST)-adjuvant and phosphate-buffered saline-adjuvant served as nonvaccinated controls. Three weeks after the last vaccination, all animals were challenged intraperitoneally with 10(8) L. interrogans serovar Pomona bacteria (NVSL 1427-35-093002). All hamsters immunized with recombinant LigA survived after challenge and had no significant histopathological changes. In contrast, nonimmunized and rGST-immunized hamsters were subjected to lethal doses, and the hamsters that survived showed severe tubulointerstitial nephritis. All vaccinated animals showed a rise in antibody titers against rLigA. Results from this study indicate that rLigA is a potential vaccine candidate against L. interrogans serovar Pomona infection.
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Affiliation(s)
- Raghavan U M Palaniappan
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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Viriyakosol S, Matthias MA, Swancutt MA, Kirkland TN, Vinetz JM. Toll-like receptor 4 protects against lethal Leptospira interrogans serovar icterohaemorrhagiae infection and contributes to in vivo control of leptospiral burden. Infect Immun 2006; 74:887-95. [PMID: 16428731 PMCID: PMC1360355 DOI: 10.1128/iai.74.2.887-895.2006] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The roles of innate immune responses in protection from or pathogenesis of severe leptospirosis remain unclear. We examined the role of Toll-like receptors (TLRs) in mouse infection and macrophage responses to Leptospira. C3H/HeJ mice (TLR4 deficient) and C3H/HeJ-SCID mice, but not C3H/OuJ mice (TLR4 intact), died after intraperitoneal infection with Leptospira interrogans serovar Icterohaemorrhagiae. Death in both C3H/HeJ mouse strains was associated with jaundice and pulmonary hemorrhage, similar to the patient from whom the isolate was obtained. In chronic sublethal infection, TLR4-deficient mice harbored more leptospires in liver, lung, and kidney than control mice. Heat-killed Leptospira stimulated macrophages to secrete proinflammatory cytokines, tumor necrosis factor alpha, interleukin-6, and macrophage inflammatory protein 2 not inhibited by polymyxin B, suggesting that leptospiral lipopolysaccharide (LPS) did not drive these responses. Anti-TLR4 and anti-MD-2 but not anti-CD14 monoclonal antibodies inhibited cytokine production. Peritoneal macrophages from CD14-/- and TLR2-/- mice exhibited no defect in cytokine responses to Leptospira compared to controls. Macrophages from C3H/HeJ, TLR4-/-, and MyD88-/- mice secreted far-lower levels of cytokines than wild-type macrophages in response to Leptospira. TLR4 plays a crucial role in protection from acute lethal infection and control of leptospiral burden during sublethal chronic infection. Cytokine responses in macrophages correlated with leptospiral clearance. These TLR4-dependent but CD14/TLR2-independent responses are likely mediated by a leptospiral ligand(s) other than LPS.
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Affiliation(s)
- Suganya Viriyakosol
- Division of Infectious Diseases, Department of Medicine, University of California San Diego, 9500 Gilman Dr. 0640, La Jolla, CA 92093-0640, USA
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Nally JE, Fishbein MC, Blanco DR, Lovett MA. Lethal infection of C3H/HeJ and C3H/SCID mice with an isolate of Leptospira interrogans serovar copenhageni. Infect Immun 2005; 73:7014-7. [PMID: 16177383 PMCID: PMC1230959 DOI: 10.1128/iai.73.10.7014-7017.2005] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Leptospira interrogans serovar Copenhageni strain RJ16441, a blood isolate from humans with the severe pulmonary form of leptospirosis, has previously been shown to cause fatal pulmonary hemorrhage in guinea pigs and asymptomatic chronic renal tubular colonization with urinary shedding in rats. In this study, RJ16441 caused lethal infection of both C3H/HeJ and C3H/SCID mice, but no hemorrhagic phenomena were observed.
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Affiliation(s)
- Jarlath E Nally
- Department of Medicine, Division of Infectious Diseases, University of California--Los Angeles, 90095, USA.
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Nally JE, Chantranuwat C, Wu XY, Fishbein MC, Pereira MM, Da Silva JJP, Blanco DR, Lovett MA. Alveolar septal deposition of immunoglobulin and complement parallels pulmonary hemorrhage in a guinea pig model of severe pulmonary leptospirosis. THE AMERICAN JOURNAL OF PATHOLOGY 2004; 164:1115-27. [PMID: 14982864 PMCID: PMC1614724 DOI: 10.1016/s0002-9440(10)63198-7] [Citation(s) in RCA: 140] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Human patients suffering from leptospirosis present with a diverse array of clinical manifestations, including the more severe and often fatal pulmonary form of the disease. The etiology of pulmonary hemorrhage is unclear. Isolates of Leptospira acquired from patients suffering from pulmonary hemorrhage were used to develop a guinea pig model of pulmonary hemorrhage. Gross findings post-infection confirmed extensive hemorrhage in the lungs and on peritoneal surfaces as the likely cause of death. Immunohistochemistry confirmed the presence of large numbers of leptospires in kidney, liver, intestinal tissues, and spleen, but few inflammatory cells were seen. In marked contrast, few leptospires were detected in infected hemorrhagic lung tissue. Blood chemistries and hematology did not reveal the etiology of the hemorrhage observed. There was no chemical or microscopic evidence for disseminated intravascular coagulation. To ascertain an immunopathologic role during disease, immunofluorescence was performed on infected lung tissues and confirmed the presence of IgM, IgG, IgA, and C3 along the alveolar basement membrane. This suggests that an autoimmune process may be the etiology of fatal pulmonary hemorrhage in leptospirosis.
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Affiliation(s)
- Jarlath E Nally
- Division of Infectious Diseases, Department of Medicine, University of California Los Angeles, Los Angeles, California 90095, USA.
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Truccolo J, Charavay F, Merien F, Perolat P. Quantitative PCR assay to evaluate ampicillin, ofloxacin, and doxycycline for treatment of experimental leptospirosis. Antimicrob Agents Chemother 2002; 46:848-53. [PMID: 11850271 PMCID: PMC127490 DOI: 10.1128/aac.46.3.848-853.2002] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The susceptibility of Leptospira interrogans serovar icterohaemorrhagiae strain Verdun to selected antibiotics used in medical practice (ampicillin, doxycycline, and ofloxacin) was evaluated in a Syrian hamster model, to determine the efficacy of these antibiotics during the course of the disease. A quantitative PCR assay was used to monitor the density of leptospires in blood and in target organs (liver, kidney, lung, heart, and spleen). Our results demonstrated the ability of ampicillin at a high dose (100 mg/kg of body weight) to clear leptospires from the host, except from kidneys and heart, where 10(2) leptospires/g remained at day 6. Ofloxacin (30 mg/kg) was unable to clear bacteria from blood or kidneys. With doxycycline (10 mg/kg), the clearance of leptospires occurred in 2 days in all the target organs studied, with the exception of liver, which required 3 days. Our data demonstrate the value of monitoring the kinetics of experimental leptospiral infection in order to accurately evaluate the efficacy of antibiotics. We have demonstrated the potential value of doxycycline for the treatment of leptospirosis cases, except in circumstances where it is contraindicated. This experimental model could be used to define better therapeutic strategies for human leptospirosis, by testing associations or new formulations of antibiotics.
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Affiliation(s)
- Johann Truccolo
- Leptospira Laboratory, Institut Pasteur de Nouvelle-Calédonie, 98845 Nouméa Cedex, New Caledonia
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Truccolo J, Serais O, Merien F, Perolat P. Following the course of human leptospirosis: evidence of a critical threshold for the vital prognosis using a quantitative PCR assay. FEMS Microbiol Lett 2001; 204:317-21. [PMID: 11731142 DOI: 10.1111/j.1574-6968.2001.tb10904.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
In order to follow the course of acute human leptospirosis, an ELISA microtiter plate hybridization method was developed for the quantitative determination of Leptospira spp. in biological samples after PCR. The biotin-labelled amplified product (331 bp from the rrs gene) was hybridized with a complementary capture probe covalently linked onto aminated polystyrene wells, and detected using a colorimetric reaction. The mean detection limit was 50 copies per 10 microl. In a prospective study of human leptospirosis cases, we obtained evidence that a density of 10(4) leptospires per ml of blood is a critical threshold for the vital prognosis of the patients. The practicability of the method makes it suitable for use in tropical areas for multicentric studies. Such studies could lead to a better knowledge of the natural history of the human disease. The method is also suitable for experimental evaluation of improved antibiotic treatments for leptospirosis.
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Affiliation(s)
- J Truccolo
- Leptospira Laboratory, Institut Pasteur de Nouvelle-Calédonie, P.O. Box 61, 98845 Cedex, Nouméa, New Caledonia
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Younes-Ibrahim M, Buffin-Meyer B, Cheval L, Burth P, Castro-Faria MV, Barlet-Bas C, Marsy S, Doucet A. Na,K-ATPase: a molecular target for Leptospira interrogans endotoxin. Braz J Med Biol Res 1997; 30:213-23. [PMID: 9239307 DOI: 10.1590/s0100-879x1997000200009] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
On the basis of our report that a glycolipoprotein fraction (GLP) extracted from Leptospira interrogans contains a potent inhibitor of renal Na,K-ATPase, we proposed that GLP-induced inhibition of Na,K-ATPase might be the primary cellular defect in the physiopathology of leptospirosis. The present study was designed to test this hypothesis by determining whether or not 1). GLP inhibits all the isoforms of Na,K-ATPase which are expressed in the tissues affected by leptospirosis, 2) Na,K-ATPase from leptospirosis-resistant species, such as the rat, is sensitive to GLP, 3) GLP inhibits Na,K-ATPase from intact cells, and 4) GLP inhibits ouabain-sensitive H,K-ATPase. The results indicate that in the rabbit, a leptospirosis-sensitive species, GLP inhibits with similar efficiency (apparent IC50: 120-220 micrograms protein GLP/ml) all isoforms of Na,K-ATPase known to be expressed in target tissues for the disease. Na,K-ATPase from rat kidney displays a sensitivity to GLP similar to that of the rabbit kidney enzyme (apparent IC50: 25-80 and 50-150 micrograms protein GLP/ml for rat and rabbit, respectively), indicating that resistance to the disease does not result from the resistance of Na,K-ATPase to GLP. GLP also reduces ouabain-sensitive rubidium uptake in rat thick ascending limbs (pmol mm-1 min-1 +/- SEM; control: 23.8 +/- 1.8; GLP, 88 micrograms protein/ml: 8.2 +/- 0.9), demonstrating that it is active in intact cells. Finally, GLP had no demonstrable effect on renal H,K-ATPase activity, even on the ouabain-sensitive form, indicating that the active principle of GLP is more specific for Na,K-ATPase than ouabain itself. Although the hypothesis remains to be demonstrated in vivo, the present findings are compatible with the putative role of GLP-induced inhibition of Na,K-ATPase as an initial mechanism in the physiopathology of leptospirosis.
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Affiliation(s)
- M Younes-Ibrahim
- Laboratoire de Biologie Integrée des Cellules Rénales, CNRS URA 1859, Commissariat à l'Energie Atomique, Saclay, France
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Midwinter A, Vinh T, Faine S, Adler B. Characterization of an antigenic oligosaccharide from Leptospira interrogans serovar pomona and its role in immunity. Infect Immun 1994; 62:5477-82. [PMID: 7960129 PMCID: PMC303291 DOI: 10.1128/iai.62.12.5477-5482.1994] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
An antigenic oligosaccharide fraction derived from the lipopolysaccharide of Leptospira interrogans serovar pomona was isolated by endo-glycosidase H digestion and column chromatography. The oligosaccharide contained rhamnose, ribose, glucose, and glucosamine and inhibited the binding of opsonic, protective monoclonal antibodies directed against the lipopolysaccharide. When conjugated to diphtheria toxoid, the oligosaccharide elicited the production of agglutinating, opsonic antibodies.
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Affiliation(s)
- A Midwinter
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
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Yukawa M, Mochizuki K, Kosaka T, Kamata H, Awaya A, Kobayashi H, Onodera T. Protective effects of serum thymic factor to Leptospira interrogans serovar Copenhageni infection in Mongolian gerbils. Vet Microbiol 1994; 41:99-106. [PMID: 7801529 DOI: 10.1016/0378-1135(94)90139-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The susceptibility to Leptospira interrogans serovar copenhageni in Mongolian gerbils treated with 10 micrograms of serum thymic factor (FTS) 1 day before infection was examined. Susceptibility of gerbils treated 5 times with 10 micrograms of FTS was also investigated. Mortality of FTS-treated gerbils was significantly lower than that of controls when small challenge doses were used. To analyse the FTS-induced resistance to leptospiral infection, natural killer (NK) cell activity and macrophage activity were studied. Macrophage activity was unaltered but NK cell activity was enhanced in FTS-treated gerbils, with or without leptospiral infection. Since no side-effects of FTS were observed, this compound should be considered for the treatment of leptospirosis.
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Affiliation(s)
- M Yukawa
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, Nihon University, Kanagawa, Japan
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Brown JA, LeFebvre RB, Pan MJ. Protein and antigen profiles of prevalent serovars of Leptospira interrogans. Infect Immun 1991; 59:1772-7. [PMID: 2019441 PMCID: PMC257914 DOI: 10.1128/iai.59.5.1772-1777.1991] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Whole-cell and detergent-soluble proteins, enriched for outer membrane antigens, of the Leptospira interrogans serovars present in commercially available pentavalent vaccines (hardjo, pomona, icterohaemorrhagiae, grippotyphosa, and canicola) were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting (immunoblotting). Protein and antigenic profiles of these serovars, representing several serogroups, were compared with similar profiles of the most common North American bovine pathogen, serovar hardjo type hardjo bovis. The reference strain of serovar balcanica and a hardjoprajitno bovine field isolate (serovar hardjo) were also assayed. Coomassie blue-stained gels revealed extensive protein similarities, and Western blots demonstrated antigenic relatedness throughout the low- and high-molecular-weight regions. Possible quantitative differences in protein expression among the strains were noted, as were similarities in the protein profiles of type hardjo bovis and the balcanica reference strain. A cocktail composed of these homologous antigens may serve as an efficacious subunit vaccine for leptospirosis.
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Affiliation(s)
- J A Brown
- VM Veterinary Microbiology and Immunology, University of California, Davis 95616
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Masuzawa T, Suzuki R, Yanagihara Y. Comparison of protective effects with tetra-valent glycolipid antigens and whole cell-inactivated vaccine in experimental infection of Leptospira. Microbiol Immunol 1991; 35:199-208. [PMID: 1870437 DOI: 10.1111/j.1348-0421.1991.tb01548.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The protective antigens (PAgs), glycolipid substance, were extracted from Leptospira interrogans serovars autumnalis, hebdomadis, australis and copenhageni, which were considered as main causal serovars of human leptospirosis in Japan, with chloroform-methanol-water (1:2:0.8, [vol/vol/vol]) solution. The tetra-valent formalin-inactivated leptospiral vaccine (Weil's disease and Akiyami combined vaccine) composed of the four serovars mentioned are used as vaccine to protect human from leptospiral infection in Japan. The protective effect, agglutinating antibody-inducing activity and opsonin-inducing activity of tetra-valent PAgs were compared with those of vaccines now in use, which were supplied by two companies, Takeda Chemical Industries, Ltd., and Denka-Seiken Co., in Japan. The tetra-valent PAgs which contained 10 micrograms of each PAg protected hamsters and cyclophosphamide-treated mice from lethal infection of serovar copenhageni and induced agglutinating antibodies against the four serovars in the same degrees as vaccines. These results suggested that the tetra-valent PAgs might be useful as a component vaccine against leptospiral infection instead of formalized whole cells vaccines for human.
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Affiliation(s)
- T Masuzawa
- Department of Microbiology, School of Pharmaceutical Sciences, University of Shizuoka
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36
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Chapman AJ, Faine S, Adler B. Antigens recognized by the human immune response to vaccination with a bivalent hardjo/pomona leptospiral vaccine. FEMS MICROBIOLOGY IMMUNOLOGY 1990; 2:111-8. [PMID: 2257162 DOI: 10.1111/j.1574-6968.1990.tb03508.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Serum from volunteer subjects vaccinated with a bivalent whole cell vaccine of Leptospira interrogans serovar hardjo/serovar pomona grown in protein-free medium, was tested by the microscopic agglutination test (MAT), enzyme-immunoassay (EIA) and immunoblotting. Specific IgM antibodies to either serovars hardjo or pomona were detected in some subjects as early as 6 days after vaccination with peak antibody levels occurring 13-68 days after vaccination. Whereas all subjects produced specific IgM to both serovars, not all produced specific IgG to both serovars. Immunoblotting with hardjo sonicate revealed that all subjects produced IgM antibodies reacting with the 15, 23 and 28 kDa components of hardjo lipopolysaccharide (LPS), and most produced IgM antibodies that reacted with the 34.5 kDa flagellar doublet. In contrast, not all sera immunoblotted against pomona sonicate reacted with the 29 and 35 kDa components of pomona LPS. However all subjects produced antibodies reacting with a diffuse 14.4-27 kDa band. These antibodies appeared early in the immune response. Serum from the one vaccinated subject tested protected hamsters from acute lethal infection with serovar pomona.
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Affiliation(s)
- A J Chapman
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
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37
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Masuzawa T, Nakamura R, Shimizu T, Yanagihara Y. Heat stability of protective antigen of Leptospira interrogans serovar lai. J Clin Microbiol 1990; 28:660-3. [PMID: 2332463 PMCID: PMC267772 DOI: 10.1128/jcm.28.4.660-663.1990] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Protective antigen (PAg; glycolipid antigen; molecular size, 23 to 30 kilodaltons), the serogroup-specific antigen partially purified from leptospiral cells, is one of the most important protective antigens. The heat stability of PAg was compared with that of whole-cell (WC) antigen by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, immunoblotting, protective activity, opsonin-inducing activity, agglutinating antibody-inducing activity, and an inhibition test in an enzyme-linked immunosorbent assay. A band of 23 to 30 kilodaltons of PAg, which was seen in untreated PAg and WC, shifted to a position with a molecular size of ca. 20 kilodaltons after heat treatment of PAg at 80 degrees C for 30 min and WC at 100 degrees C for 30 min. In the enzyme-linked immunosorbent assay inhibition test with monoclonal antibody LW2 and a sonicated antigen of WC, the inhibition rate of PAg and WC to sonicated WC was reduced by heat treatment at 80 degrees C for 30 min and at 100 degrees C for 30 min, respectively. Agglutinating antibody-inducing activities and opsonin-inducing activities of PAg and WC in mice were reduced by heat treatment under the same conditions; these activities were assayed by a microscopic agglutination test and by chemical luminescence response in serum from immunized mice, respectively. Protective activity of heated PAg and heated WC in cyclophosphamide-pretreated mice agreed with the results of immunogenicity in mice. These results indicate that the Leptospira PAg is one of the important protective antigens and is altered by heat treatment at 80 degrees C. Furthermore, the immunogenicity and antigenicity of the PAg present in WC are more stable than that of the extracted PAg, and the coexistence of other cellular components with PAg might protect and stabilize PAg from the heat treatment.
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Affiliation(s)
- T Masuzawa
- Department of Microbiology, School of Pharmaceutical Sciences, University of Shizuoka, Japan
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Remesar MC, Blejer JL, Negroni R, Nejamkis MR. Cyclophosphamide effect on coccidioidomycosis in the rat. Rev Inst Med Trop Sao Paulo 1989; 31:423-9. [PMID: 2640515 DOI: 10.1590/s0036-46651989000600009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cocidioidomycosis is a systemic mycosis, endemic in arid areas of the American continent. The rat was employed as an experimental host, since it had been shown to reproduce human lesions and present a chronic course of disease with granulomas mainly restricted to lungs. Given the influence of immunosuppressive therapy on the clinical course of human coccidioidomycosis, we studied the effect of cyclophosphamide (CY) in the experimental rat model. Accordingly, animals were inoculated with 400 Coccidioides immitis arthroconidia of the Acosta strain, by intracardiacal route. As single CY doses failed to alter the course of disease, three schedules were used: A) 4 daily doses of 20 mg/kg each, prior to C. immitis inoculation; B) 4 similar daily doses after infection; and C); 6 doses of 20 mg/kg each, given from day +1 to +4 then on days +8 and +9, post infection (pi), taking day 0 as the time of fungal inoculation. The first two schedules inhibited antibody formation up to day 28 pi, without modifying cellular response to coccidioidin as measured by foodpad swelling. Initially, there was greater fungal spread than in controls receiving C. immitis alone, which proved self-limiting in the latter. In contrast, schedule C led to 55% mortality with both humoral and cellular response abrogation, accompanied by extensive C. immitis dissemination. Histology disclosed significant alterations, such as the persistence of primary infection sporangia, corresponding to the acute stage of coccidioidomycosis in the absence of granuloma development. Therefore, the observed depression in cellular immunity seems responsible for the lack of inflammatory reaction capable of restricting sporangia proliferation in tissues which, in turn, enhances pathogen spread and mortality rate.
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McGrath H, Adler B, Vinh T, Faine S. Phagocytosis of virulent and avirulent leptospires by guinea-pig and human polymorphonuclear leukocytes in vitro. Pathology 1984; 16:243-9. [PMID: 6514391 DOI: 10.3109/00313028409068531] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Chemiluminescence (CL) and electron microscopy were used to study the phagocytosis of both virulent and avirulent strains of Leptospira interrogans serovar copenhageni by guinea-pig and human polymorphonuclear leukocytes (PMN). A significant CL response was observed when guinea-pig PMN were incubated with virulent leptospires in the presence but not in the absence of specific immune serum. This response was markedly enhanced by the addition of guinea-pig complement. Phagocytosis was confirmed by the observation of intracellular leptospires in guinea-pig PMN by electron microscopy. The phagocytosis of avirulent leptospires by guinea-pig PMN and of both virulent and avirulent leptospires by human PMN required the presence of both specific immune serum and complement. Thus the ability of leptospires to resist phagocytosis by PMN in the absence of immune serum does not appear to be a major determinant of virulence.
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40
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Wang B, Sullivan J, Sullivan GW, Mandell GL. Interaction of leptospires with human polymorphonuclear neutrophils. Infect Immun 1984; 44:459-64. [PMID: 6715045 PMCID: PMC263541 DOI: 10.1128/iai.44.2.459-464.1984] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The role of the polymorphonuclear neutrophils (PMN) in defense against leptospires has not been adequately studied, in part, because of difficulty in quantitating pathogenic leptospires. By using pour plates to quantitate nonpathogenic leptospires and the most-probable-number procedure to quantitate the pathogenic leptospires, we examined the interactions of nonpathogenic Leptospira biflexa and pathogenic Leptospira interrogans serovar icterohemorrhagiae with human neutrophils. Phase-contrast, scanning electron, and transmission electron microscopic observations were made. Leptospires were incubated with PMN at 37 degrees C and tumbled together. There was no ingestion or killing of nonpathogenic leptospires (with no serum) or of pathogenic organisms (with 10% normal serum). However, when leptospires were incubated with PMN (without serum) in a pellet and then resuspended, 91 +/- 6% of nonpathogenic leptospires were removed from the supernatant, and 93 +/- 4% of these organisms were killed. The pathogenic leptospires became cell associated in a pellet, but were not killed by PMN even in the presence of 10% normal serum. Observations of morphological interactions indicated that PMN phagocytized the nonpathogenic leptospires in the absence of serum and that the pathogenic leptospires attached to but were not ingested by neutrophils in the presence of 10% normal serum. PMN do not seem to be an efficient defense factor for pathogenic leptospires in nonimmune hosts. The virulence of leptospires appears to be related to their ability to resist killing by serum and to resist ingestion and killing by neutrophils.
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Baccarini M, Bistoni F, Puccetti P, Garaci E. Natural cell-mediated cytotoxicity against Candida albicans induced by cyclophosphamide: nature of the in vitro cytotoxic effector. Infect Immun 1983; 42:1-9. [PMID: 6352489 PMCID: PMC264515 DOI: 10.1128/iai.42.1.1-9.1983] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
We have recently reported the in vivo modulation of resistance to experimental Candida albicans infection by cyclophosphamide (150 mg/kg intraperitoneally) in mice and have shown that increased resistance to the microbial challenge occurs 12 to 21 days after treatment with the drug (Bistoni et al., Infect. Immun. 40: 46-55, 1983). The event is accompanied by the appearance of a highly candidacidal cell population in the spleen and the activation of a subpopulation of natural cytotoxic effectors reactive in vitro against YAC-1 tumor cells. We now provide evidence that these anti-YAC-1 cytotoxic effectors are clearly distinct from the cyclophosphamide-induced candidacidal effectors, which seem to belong to a macrophage-monocyte lineage. The enhanced cytotoxic activity induced by cyclophosphamide was not restricted to C. albicans but was also exerted against a panel of Candida strains.
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42
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Adler B, Faine S. A pomona serogroup-specific, agglutinating antigen in Leptospira, identified by monoclonal antibodies. Pathology 1983; 15:247-50. [PMID: 6417619 DOI: 10.3109/00313028309083501] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Monoclonal antibodies were produced by hybridoma cell lines derived by fusion of mouse NS-1 myeloma cells with splenocytes from mice immunized with Leptospira interrogans serovar pomona. One hybridoma (A3) produced an IgG2a antibody which agglutinated all leptospires of the Pomona serogroup but not leptospires representative of serovars of any other serogroup. The antibody precipitated in immunodiffusions with either alkali- or phenol-extracted lipopolysaccharide and also with the TM antigen of Yanagawa et al., indicating a common determinant on both antigens. A3 antibody opsonized viable leptospires for phagocytosis by mouse macrophages in vitro.
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Bistoni F, Baccarini M, Blasi E, Marconi P, Puccetti P, Garaci E. Correlation between in vivo and in vitro studies of modulation of resistance to experimental Candida albicans infection by cyclophosphamide in mice. Infect Immun 1983; 40:46-55. [PMID: 6339410 PMCID: PMC264816 DOI: 10.1128/iai.40.1.46-55.1983] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Mice receiving a single injection of cyclophosphamide (150 mg/kg) 1 to 6 days before inoculation with viable Candida albicans showed an increased susceptibility to the challenge accompanied by a reduction in peripheral blood polymorphonuclear leukocytes and lymphocytes as well as in spleen cellularity. Several immunological in vitro functions also appeared to be dramatically depressed. Most of these hematological and functional parameters returned to control values by day 9 after cyclophosphamide administration, at a time when resistance to C. albicans infection appeared to be unchanged. However, when exposure to cyclophosphamide occurred 12 to 21 days before inoculation with the live yeast, enhanced resistance was observed with the majority of the animals surviving challenge. To gain some insight into the mechanisms underlying this late increase in resistance to C. albicans infection after cyclophosphamide administration, we analyzed a series of immunological functions, including the in vitro candidacidal activity of polymorphonuclear neutrophils and plastic-adherent and nonadherent spleen cells as well as the activity of natural killer cells and alloreactive T lymphocytes. The results show that a numerical rebound of blood polymorphonuclear neutrophils and the appearance of a highly candidacidal cell population in the spleen may be among the factors underlying the late increase in resistance to C. albicans after administration of cyclophosphamide.
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44
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Tu V, Adler B, Faine S. The role of macrophages in the protection of mice against leptospirosis: in vitro and in vivo studies. Pathology 1982; 14:463-8. [PMID: 6760092 DOI: 10.3109/00313028209092128] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Balb/c mice are naturally resistant to infection with Leptospira interrogans serovar copenhageni, but leptospires were not phagocytosed by mouse peritoneal macrophages in vitro without added specific antibody. Similar results were obtained irrespective of whether leptospires were viable or killed, virulent or avirulent, or whether macrophages were obtained from normal mice, immunized mice or mice previously infected with BCG. Suppression or stimulation of macrophage function in vivo did not affect the outcome of infection of immunosuppressed mice with leptospires; specific antibody was essential for protection from infection.
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45
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Adler B, Faine S, Muller HK, Green DE. Maturation of humoral immune response determines the susceptibility of guinea-pigs to leptospirosis. Pathology 1980; 12:529-38. [PMID: 6970358 DOI: 10.3109/00313028009086806] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Baby guinea-pigs were susceptible to infection with Leptospira interrogans serovar pomona, but rapidly became resistant as they matured. Increased resistance with increasing weight of guinea-pigs was correlated with the development of ability to produce agglutinating antibodies to leptospires and with maturation of B-cell dependent (but not T-cell dependent) areas in lymphoid organs. These observations can explain the basis of species-resistance of adult guinea-pigs to infection with serovar pomona.
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Wyburn RS. Diagnosis of hip dysplasia in dogs. Aust Vet J 1979; 55:601. [PMID: 539945 DOI: 10.1111/j.1751-0813.1979.tb07065.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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47
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Awaad MH, Gräf K, Schmatz HD, Krauss H. Electrophoretic changes in serum transferrin and gammaglobulins following rickettsia mooseri infection in cyclophosphamide treated mice. ZENTRALBLATT FUR VETERINARMEDIZIN. REIHE B. JOURNAL OF VETERINARY MEDICINE. SERIES B 1978; 25:586-95. [PMID: 83756 DOI: 10.1111/j.1439-0450.1978.tb00767.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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49
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Adler B, Faine S. Serological specificities of erythrocyte-sensitizing antigens of leptospires. FEMS Microbiol Lett 1978. [DOI: 10.1111/j.1574-6968.1978.tb02840.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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50
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Adler B, Faine S. Host immunological mechanisms in the resistance of mice to leptospiral infections. Infect Immun 1977; 17:67-72. [PMID: 885617 PMCID: PMC421082 DOI: 10.1128/iai.17.1.67-72.1977] [Citation(s) in RCA: 78] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Several serovars of Leptospira virulent for hamsters and guinea pigs caused acute lethal leptospirosis in mice immunosuppressed with cyclophosphamide. Neither BCG vaccine nor Corynebacterium parvum suspension influenced the course of leptospiral infection in either immunosuppressed or normal BALB/c mice. Nude athymic mice produced anti-leptospiral antibody and were therefore resistant to infection with leptospires. Nude mice were made susceptible with cyclophosphamide but were immune if they had acquired antibody from previous infection or immunization. The evidence suggests that mechanisms of resistance to primary infection and immunity to reinfection are exclusively humorally mediated in mice. The roles of host and microbial factors in the outcome of infection are discussed.
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