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Varma VP, Kadivella M, Kavela S, Faisal SM. Leptospira Lipid A Is a Potent Adjuvant That Induces Sterilizing Immunity against Leptospirosis. Vaccines (Basel) 2023; 11:1824. [PMID: 38140228 PMCID: PMC10748165 DOI: 10.3390/vaccines11121824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/16/2023] [Accepted: 11/30/2023] [Indexed: 12/24/2023] Open
Abstract
Leptospirosis is a globally significant zoonotic disease. The current inactivated vaccine offers protection against specific serovars but does not provide complete immunity. Various surface antigens, such as Leptospira immunoglobulin-like proteins (LigA and LigB), have been identified as potential subunit vaccine candidates. However, these antigens require potent adjuvants for effectiveness. Bacterial lipopolysaccharides (LPSs), including lipid A, are a well-known immunostimulant, and clinical adjuvants often contain monophosphoryl lipid A (MPLA). Being less endotoxic, we investigated the adjuvant properties of lipid A isolated from L. interrogans serovar Pomona (PLA) in activating innate immunity and enhancing antigen-specific adaptive immune responses. PLA activated macrophages to a similar degree as MPLA, albeit at a higher dose, suggesting that it is less potent in stimulation than MPLA. Mice immunized with a variable portion of LigA (LAV) combined with alum and PLA (LAV-alum-PLA) exhibited significantly higher levels of LAV-specific humoral and cellular immune responses compared to alum alone but similar to those induced by alum-MPLA. The adjuvant activity of PLA resembles that of MPLA and is primarily achieved through the increased recruitment, activation, and uptake of antigens by innate immune cells. Furthermore, like MPLA, PLA formulation establishes a long-lasting memory response. Notably, PLA demonstrated superior potency than MPLA formulation and provided sterilizing immunity against the leptospirosis in a hamster model. Overall, our study sheds light on the adjuvant properties of Leptospira lipid A and offers promising avenues for developing LPS-based vaccines against this devastating zoonotic disease.
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Affiliation(s)
- Vivek P. Varma
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad 500032, India; (V.P.V.); (M.K.); (S.K.)
- Graduate Studies, Manipal Academy of Higher Education, Manipal 576104, India
| | - Mohammad Kadivella
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad 500032, India; (V.P.V.); (M.K.); (S.K.)
- Regional Centre for Biotechnology, Faridabad 121001, India
| | - Sridhar Kavela
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad 500032, India; (V.P.V.); (M.K.); (S.K.)
| | - Syed M. Faisal
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad 500032, India; (V.P.V.); (M.K.); (S.K.)
- Regional Centre for Biotechnology, Faridabad 121001, India
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2
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Pětrošová H, Mikhael A, Culos S, Giraud-Gatineau A, Gomez AM, Sherman ME, Ernst RK, Cameron CE, Picardeau M, Goodlett DR. Lipid A structural diversity among members of the genus Leptospira. Front Microbiol 2023; 14:1181034. [PMID: 37303810 PMCID: PMC10248169 DOI: 10.3389/fmicb.2023.1181034] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 05/02/2023] [Indexed: 06/13/2023] Open
Abstract
Lipid A is the hydrophobic component of bacterial lipopolysaccharide and an activator of the host immune system. Bacteria modify their lipid A structure to adapt to the surrounding environment and, in some cases, to evade recognition by host immune cells. In this study, lipid A structural diversity within the Leptospira genus was explored. The individual Leptospira species have dramatically different pathogenic potential that ranges from non-infectious to life-threatening disease (leptospirosis). Ten distinct lipid A profiles, denoted L1-L10, were discovered across 31 Leptospira reference species, laying a foundation for lipid A-based molecular typing. Tandem MS analysis revealed structural features of Leptospira membrane lipids that might alter recognition of its lipid A by the host innate immune receptors. Results of this study will aid development of strategies to improve diagnosis and surveillance of leptospirosis, as well as guide functional studies on Leptospira lipid A activity.
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Affiliation(s)
- Helena Pětrošová
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
- University of Victoria Genome British Columbia Proteomics Center, University of Victoria, Victoria, BC, Canada
| | - Abanoub Mikhael
- University of Victoria Genome British Columbia Proteomics Center, University of Victoria, Victoria, BC, Canada
| | - Sophie Culos
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | | | - Alloysius M. Gomez
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | - Matthew E. Sherman
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, United States
| | - Robert K. Ernst
- Department of Microbial Pathogenesis, University of Maryland, Baltimore, MD, United States
| | - Caroline E. Cameron
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
- Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington, Seattle, WA, United States
| | - Mathieu Picardeau
- Institut Pasteur, Université Paris Cité, CNRS UMR 6047, Biology of Spirochetes Unit, Paris, France
| | - David R. Goodlett
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
- University of Victoria Genome British Columbia Proteomics Center, University of Victoria, Victoria, BC, Canada
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3
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Bonhomme D, Hernandez-Trejo V, Papadopoulos S, Pigache R, Fanton d'Andon M, Outlioua A, Boneca IG, Werts C. Leptospira interrogans Prevents Macrophage Cell Death and Pyroptotic IL-1β Release through Its Atypical Lipopolysaccharide. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 210:459-474. [PMID: 36602965 DOI: 10.4049/jimmunol.2200584] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 12/03/2022] [Indexed: 01/06/2023]
Abstract
Leptospira interrogans are bacteria that can infect all vertebrates and are responsible for leptospirosis, a neglected zoonosis. Some hosts, such as humans, are susceptible to the disease, whereas mice are resistant and get chronically colonized. Although leptospires escape recognition by some immune receptors, they activate the NOD-like receptor pyrin 3-inflammasome and trigger IL-1β secretion. Classically, IL-1β secretion is associated with lytic inflammatory cell death called pyroptosis, resulting from cytosolic LPS binding to inflammatory caspases, such as caspase 11. Interestingly, we showed that L. interrogans and Leptospira biflexa do not trigger cell death in either murine, human, hamster, or bovine macrophages, escaping both pyroptosis and apoptosis. We showed, in murine cells, that the mild IL-1β secretion induced by leptospires occurred through nonlytic caspase 8-dependent gasdermin D pore formation and not through activation of caspase 11/noncanonical inflammasome. Strikingly, we demonstrated a potent antagonistic effect of pathogenic L. interrogans and their atypical LPS on spontaneous and Escherichia coli LPS-induced cell death. Indeed, LPS of L. interrogans efficiently prevents caspase 11 dimerization and subsequent massive gasdermin D cleavage. Finally, we showed that pyroptosis escape by leptospires prevents massive IL-1β release, and we consistently found no major role of IL-1R in controlling experimental leptospirosis in vivo. Overall, to our knowledge, our findings described a novel mechanism by which leptospires dampen inflammation, thus potentially contributing to their stealthiness.
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Affiliation(s)
- Delphine Bonhomme
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Veronica Hernandez-Trejo
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Stylianos Papadopoulos
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Rémi Pigache
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Martine Fanton d'Andon
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Ahmed Outlioua
- INSERM, UMR_S 1197, Hôpital Paul Brousse, Villejuif, France.,Université Paris-Saclay, Paris, France; and.,Health and Environment Laboratory, Aïn Chock Faculty of Sciences, Hassan II University of Casablanca, Casablanca, Morocco
| | - Ivo G Boneca
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Catherine Werts
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
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4
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Novak A, Hindriks E, Hoek A, Veraart C, Broens EM, Ludwig I, Rutten V, Sloots A, Broere F. Cellular and humoral immune responsiveness to inactivated Leptospira interrogans in dogs vaccinated with a tetravalent Leptospira vaccine. Vaccine 2023; 41:119-129. [PMID: 36411135 DOI: 10.1016/j.vaccine.2022.11.017] [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: 08/30/2022] [Revised: 11/09/2022] [Accepted: 11/13/2022] [Indexed: 11/19/2022]
Abstract
Vaccination is commonly used to protect dogs against leptospirosis, however, memory immune responses induced by canine Leptospira vaccines have not been studied. In the present study, antibody and T cell mediated responses were assessed in dogs before and 2 weeks after annual revaccination with a commercial tetravalent Leptospira vaccine containing serogroups Canicola and Australis. Vaccination significantly increased average log2 IgG titers from 6.50 to 8.41 in year 1, from 5.99 to 7.32 in year 2, from 5.32 to 8.32 in year 3 and from 5.32 to 7.82 in year 4. The CXCL-10 levels, induced by in vitro stimulation of PBMC with Canicola and Australis, respectively, significantly increased from 1039.05 pg/ml and 1037.38 pg/ml before vaccination to 2547.73 pg/ml and 2730.38 pg/ml after vaccination. IFN-γ levels increased from 85.60 pg/ml and 178.13 pg/ml before vaccination to 538.62 pg/ml and 210.97 pg/ml after vaccination. The percentage of proliferating CD4+ T cells in response to respective Leptospira strains significantly increased from 1.43 % and 1.25 % before vaccination to 24.11 % and 14.64 % after vaccination. Similar responses were also found in the CD8+ T cell subset. Vaccination also significantly enhanced the percentages of central memory CD4+ T cells from 12 % to 26.97 % and 27.65 %, central memory CD8+ T cells from 3 % to 9.47 % and 7.55 %, and effector CD8+ T cells from 3 % to 7.6 % and 6.42 %, as defined by the expression of CD45RA and CD62L, following stimulation with Canicola and Australis, respectively. Lastly, enhanced expression of the activation marker CD25 on T cells after vaccination was found. Together, our results show that next to IgG responses, also T cell responses are induced in dogs upon annual revaccination with a tetravalent Leptospira vaccine, potentially contributing to protection.
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Affiliation(s)
- Andreja Novak
- Division Infectious Diseases & Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, the Netherlands; Intravacc, Bilthoven, the Netherlands
| | - Esther Hindriks
- Division Infectious Diseases & Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, the Netherlands
| | - Aad Hoek
- Division Infectious Diseases & Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, the Netherlands
| | - Claire Veraart
- Division Infectious Diseases & Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, the Netherlands
| | - Els M Broens
- Division Infectious Diseases & Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, the Netherlands
| | - Irene Ludwig
- Division Infectious Diseases & Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, the Netherlands
| | - Victor Rutten
- Division Infectious Diseases & Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, the Netherlands; Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
| | | | - Femke Broere
- Division Infectious Diseases & Immunology, Department Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, the Netherlands; Division Internal Medicine of Companion Animals, Department Clinical Science, Faculty of Veterinary Medicine, Utrecht University, the Netherlands
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5
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Russell FD, Visagie JC, Noll JL. Secretion of IL-6 by fibroblasts exposed to Australian honeys involves lipopolysaccharide and is independent of floral source. Sci Rep 2022; 12:16628. [PMID: 36198760 PMCID: PMC9534836 DOI: 10.1038/s41598-022-21130-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 09/22/2022] [Indexed: 11/18/2022] Open
Abstract
Honey stimulates cellular secretion of cytokines, which has been attributed to activation of lipopolysaccharide (LPS)-dependent and LPS-independent pathways. The objective of this study was to identify whether LPS is present in Australian honey samples at levels that can stimulate interleukin-6 (IL-6) secretion by fibroblasts and whether it can transduce cell signalling by activating toll-like receptor 4 (TLR4). IL-6 was measured in culture media of fibroblasts exposed to honey for 24 h. LPS was detected in a 0.125 mg/mL solution of grey ironbark honey (0.61 ± 0.05 ng/g honey). TLR4 signalling was observed in RAW264.7 macrophages that were exposed to honey and this was prevented by preincubating the honey with the LPS-neutralising agent, polymyxin B. Australian Eucalyptus, Leptospermum and Cyathode honeys stimulated IL-6 secretion in cultured human dermal fibroblasts. To examine whether the response was dependent on floral source, fibroblasts were exposed to four different samples of grey ironbark honey obtained from Queensland and New South Wales, Australia. The magnitude of the cytokine response to these honeys was highly varied. We conclude that Australian honeys contain endotoxin at levels that can stimulate IL-6 secretion by fibroblasts and that signalling in macrophages involves TLR4 activation. The IL-6 secretory response was independent of floral source.
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Affiliation(s)
- Fraser D Russell
- Centre for Bioinnovation, University of the Sunshine Coast, Maroochydore DC, QLD, 4558, Australia. .,School of Health and Behavioural Sciences, University of the Sunshine Coast, Maroochydore DC, QLD, 4558, Australia.
| | - Jeanne C Visagie
- School of Health and Behavioural Sciences, University of the Sunshine Coast, Maroochydore DC, QLD, 4558, Australia
| | - Jamie L Noll
- School of Health and Behavioural Sciences, University of the Sunshine Coast, Maroochydore DC, QLD, 4558, Australia
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6
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Novak A, Pennings JLA, van der Maas L, Meiring HD, Ludwig I, Verkoeijen S, Rutten V, Broere F, Sloots A. Transcriptome and proteome analysis of innate immune responses to inactivated Leptospira and bivalent Leptospira vaccines in canine 030-D cells. Sci Rep 2022; 12:13418. [PMID: 35927283 PMCID: PMC9352656 DOI: 10.1038/s41598-022-16457-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 07/11/2022] [Indexed: 11/09/2022] Open
Abstract
Mandatory potency testing of Leptospira vaccine batches relies partially on in vivo procedures, requiring large numbers of laboratory animals. Cell-based assays could replace in vivo tests for vaccine quality control if biomarkers indicative of Leptospira vaccine potency are identified. We investigated innate immune responsiveness induced by inactivated L. interrogans serogroups Canicola and Icterohaemorrhagiae, and two bivalent, non-adjuvanted canine Leptospira vaccines containing the same serogroups. First, the transcriptome and proteome analysis of a canine monocyte/macrophage 030-D cell line stimulated with Leptospira strains, and vaccine B revealed more than 900 DEGs and 23 DEPs in common to these three stimuli. Second, comparison of responses induced by vaccine B and vaccine D revealed a large overlap in DEGs and DEPs as well, suggesting potential to identify biomarkers indicative of Leptospira vaccine quality. Because not many common DEPs were identified, we selected seven molecules from the identified DEGs, associated with pathways related to innate immunity, of which CXCL-10, IL-1β, SAA, and complement C3 showed increased secretion upon stimulation with both Leptospira vaccines. These molecules could be interesting targets for development of biomarker-based assays for Leptospira vaccine quality control in the future. Additionally, this study contributes to the understanding of the mechanisms by which Leptospira vaccines induce innate immune responses in the dog.
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Affiliation(s)
- Andreja Novak
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.,Intravacc, Bilthoven, The Netherlands
| | - Jeroen L A Pennings
- Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | | | | | - Irene Ludwig
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Saertje Verkoeijen
- Research Centre Healthy and Sustainable Living, Innovative Testing in Life Sciences and Chemistry, University of Applied Sciences Utrecht, Utrecht, The Netherlands
| | - Victor Rutten
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.,Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
| | - Femke Broere
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.,Division of Internal Medicine of Companion Animals, Department of Clinical Science, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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7
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Bonhomme D, Werts C. Host and Species-Specificities of Pattern Recognition Receptors Upon Infection With Leptospira interrogans. Front Cell Infect Microbiol 2022; 12:932137. [PMID: 35937697 PMCID: PMC9353586 DOI: 10.3389/fcimb.2022.932137] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 06/24/2022] [Indexed: 12/12/2022] Open
Abstract
Leptospirosis is a zoonotic infectious disease affecting all vertebrates. It is caused by species of the genus Leptospira, among which are the highly pathogenic L. interrogans. Different mammals can be either resistant or susceptible to the disease which can present a large variety of symptoms. Humans are mostly asymptomatic after infection but can have in some cases symptoms varying from a flu-like syndrome to more severe forms such as Weil's disease, potentially leading to multiorgan failure and death. Similarly, cattle, pigs, and horses can suffer from acute forms of the disease, including morbidity, abortion, and uveitis. On the other hand, mice and rats are resistant to leptospirosis despite chronical colonization of the kidneys, excreting leptospires in urine and contributing to the transmission of the bacteria. To this date, the immune mechanisms that determine the severity of the infection and that confer susceptibility to leptospirosis remain enigmatic. To our interest, differential immune sensing of leptospires through the activation of or escape from pattern recognition receptors (PRRs) by microbe-associated molecular patterns (MAMPs) has recently been described. In this review, we will summarize these findings that suggest that in various hosts, leptospires differentially escape recognition by some Toll-like and NOD-like receptors, including TLR4, TLR5, and NOD1, although TLR2 and NLRP3 responses are conserved independently of the host. Overall, we hypothesize that these innate immune mechanisms could play a role in determining host susceptibility to leptospirosis and suggest a central, yet complex, role for TLR4.
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Affiliation(s)
| | - Catherine Werts
- Institut Pasteur, Université de Paris, CNRS UMR2001, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
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Santecchia I, Bonhomme D, Papadopoulos S, Escoll P, Giraud-Gatineau A, Moya-Nilges M, Vernel-Pauillac F, Boneca IG, Werts C. Alive Pathogenic and Saprophytic Leptospires Enter and Exit Human and Mouse Macrophages With No Intracellular Replication. Front Cell Infect Microbiol 2022; 12:936931. [PMID: 35899053 PMCID: PMC9310662 DOI: 10.3389/fcimb.2022.936931] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 06/14/2022] [Indexed: 02/03/2023] Open
Abstract
Leptospira interrogans are pathogenic bacteria responsible for leptospirosis, a zoonosis impacting 1 million people per year worldwide. Leptospires can infect all vertebrates, but not all hosts develop similar symptoms. Human and cattle may suffer from mild to acute illnesses and are therefore considered as sensitive to leptospirosis. In contrast, mice and rats remain asymptomatic upon infection, although they get chronically colonized in their kidneys. Upon infection, leptospires are stealth pathogens that partially escape the recognition by the host innate immune system. Although leptospires are mainly extracellular bacteria, it was suggested that they could also replicate within macrophages. However, contradictory data in the current literature led us to reevaluate these findings. Using a gentamicin-protection assay coupled to high-content (HC) microscopy, we observed that leptospires were internalized in vivo upon peritoneal infection of C57BL/6J mice. Additionally, three different serotypes of pathogenic L. interrogans and the saprophytic L. biflexa actively infected both human (PMA differentiated) THP1 and mouse RAW264.7 macrophage cell lines. Next, we assessed the intracellular fate of leptospires using bioluminescent strains, and we observed a drastic reduction in the leptospiral intracellular load between 3 h and 6 h post-infection, suggesting that leptospires do not replicate within these cells. Surprisingly, the classical macrophage microbicidal mechanisms (phagocytosis, autophagy, TLR-mediated ROS, and RNS production) were not responsible for the observed decrease. Finally, we demonstrated that the reduction in the intracellular load was associated with an increase of the bacteria in the supernatant, suggesting that leptospires exit both human and murine macrophages. Overall, our study reevaluated the intracellular fate of leptospires and favors an active entrance followed by a rapid exit, suggesting that leptospires do not have an intracellular lifestyle in macrophages.
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Affiliation(s)
- Ignacio Santecchia
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Delphine Bonhomme
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Stylianos Papadopoulos
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Pedro Escoll
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, Unité Biologie des Bactéries Intracellulaires, Paris, France
| | - Alexandre Giraud-Gatineau
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, Unité de Biologie des Spirochètes, Paris, France
| | - Maryse Moya-Nilges
- Institut Pasteur, Université Cité Paris, Plateforme de Bio-imagerie Ultrastructurale, Paris, France
| | - Frédérique Vernel-Pauillac
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Ivo Gomperts Boneca
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
| | - Catherine Werts
- Institut Pasteur, Université Cité Paris, CNRS UMR6047, INSERM U1306, Unité de Biologie et Génétique de la Paroi Bactérienne, Paris, France
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