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Hamond C, Adam EN, Stone NE, LeCount K, Anderson T, Putz EJ, Camp P, Hicks J, Stuber T, van der Linden H, Bayles DO, Sahl JW, Schlater LK, Wagner DM, Nally JE. Identification of equine mares as reservoir hosts for pathogenic species of Leptospira. Front Vet Sci 2024; 11:1346713. [PMID: 38784659 PMCID: PMC11112012 DOI: 10.3389/fvets.2024.1346713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 04/24/2024] [Indexed: 05/25/2024] Open
Abstract
Equine leptospirosis can result in abortion, stillbirth, neonatal death, placentitis, and uveitis. Horses can also act as subclinical reservoir hosts of infection, which are characterized as asymptomatic carriers that persistently excrete leptospires and transmit disease. In this study, PCR and culture were used to assess urinary shedding of pathogenic Leptospira from 37 asymptomatic mares. Three asymptomatic mares, designated as H2, H8, and H9, were PCR-positive for lipL32, a gene specific for pathogenic species of Leptospira. One asymptomatic mare, H9, was culture-positive, and the recovered isolate was classified as L. kirschneri serogroup Australis serovar Rushan. DNA capture and enrichment of Leptospira genomic DNA from PCR-positive, culture-negative samples determined that asymptomatic mare H8 was also shedding L. kirschneri serogroup Australis, whereas asymptomatic mare H2 was shedding L. interrogans serogroup Icterohaemorrhagiae. Sera from all asymptomatic mares were tested by the microscopic agglutination test (MAT) and 35 of 37 (94.6%) were seropositive with titers ranging from 1:100 to 1:3200. In contrast to asymptomatic mares, mare H44 presented with acute spontaneous abortion and a serum MAT titer of 1:102,400 to L. interrogans serogroup Pomona serovar Pomona. Comparison of L. kirschneri serogroup Australis strain H9 with that of L. interrogans serogroup Pomona strain H44 in the hamster model of leptospirosis corroborated differences in virulence of strains. Since lipopolysaccharide (LPS) is a protective antigen in bacterin vaccines, the LPS of strain H9 (associated with subclinical carriage) was compared with strain H44 (associated with spontaneous abortion). This revealed different LPS profiles and immunoreactivity with reference antisera. It is essential to know what species and serovars of Leptospira are circulating in equine populations to design efficacious vaccines and diagnostic tests. Our results demonstrate that horses in the US can act as reservoir hosts of leptospirosis and shed diverse pathogenic Leptospira species via urine. This report also details the detection of L. kirschneri serogroup Australis serovar Rushan, a species and serotype of Leptospira, not previously reported in the US.
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Affiliation(s)
- Camila Hamond
- National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Ames, IA, United States
- National Centers for Animal Health Leptospira Working Group, U.S. Department of Agriculture, Ames, IA, United States
| | - Emma N. Adam
- Department of Veterinary Science, University of Kentucky, Maxwell H. Gluck Equine Research Center, Lexington, KY, United States
| | - Nathan E. Stone
- The Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Karen LeCount
- National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Ames, IA, United States
- National Centers for Animal Health Leptospira Working Group, U.S. Department of Agriculture, Ames, IA, United States
| | - Tammy Anderson
- National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Ames, IA, United States
- National Centers for Animal Health Leptospira Working Group, U.S. Department of Agriculture, Ames, IA, United States
| | - Ellie J. Putz
- Infectious Bacterial Diseases Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, United States
| | - Patrick Camp
- National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Ames, IA, United States
| | - Jessica Hicks
- National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Ames, IA, United States
| | - Tod Stuber
- National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Ames, IA, United States
| | - Hans van der Linden
- Department of Medical Microbiology and Infection Prevention, World Organisation for Animal Health (WOAH) and National Collaborating Centre for Reference and Research on Leptospirosis, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Darrell O. Bayles
- Infectious Bacterial Diseases Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, United States
| | - Jason W. Sahl
- The Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Linda K. Schlater
- National Veterinary Services Laboratories, Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Ames, IA, United States
- National Centers for Animal Health Leptospira Working Group, U.S. Department of Agriculture, Ames, IA, United States
| | - David M. Wagner
- The Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Jarlath E. Nally
- National Centers for Animal Health Leptospira Working Group, U.S. Department of Agriculture, Ames, IA, United States
- Infectious Bacterial Diseases Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, United States
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Putz EJ, Fernandes LGV, Sarlo Davila KM, Whitelegge J, Lippolis JD, Nally JE. Proteomic profiles of Leptospira borgpetersenii serovar Hardjo strains JB197 and HB203 cultured at different temperatures. J Proteomics 2024; 295:105106. [PMID: 38320623 DOI: 10.1016/j.jprot.2024.105106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 01/04/2024] [Accepted: 01/19/2024] [Indexed: 02/08/2024]
Abstract
Leptospirosis is a global zoonotic disease affecting humans, domestic, and wild animals. Leptospira are typically shed in the urine of reservoir hosts which persist in suitable environments where incidental host transmission occurs after direct contact with infected urine or contaminated environments. Interestingly, serologically identical L. borgpetersenii serovar Hardjo strains JB197 and HB203 show divergent disease severity in the hamster model; JB197 causes severe acute infection while HB203 causes persistent chronic infection. Historically, serovar Hardjo was limited to culture at 29 °C, but utilization of HAN media allows propagation from host tissues at 37 °C. Here, the proteome of strains JB197 and HB203 were characterized after culture from experimentally challenged hamsters at 29 °C and 37 °C. Comparative analyses of JB197 and HB203 samples cultured at 29 °C yielded 425 significantly differentially expressed (DE) proteins, while strains at 37 °C yielded 613 DE proteins including prominent outer membrane proteins and known virulence factors. In agreement, membrane protein GO terms were identified by STRING network analyses along with numerous metabolic KEGG pathways consistent with condition differences. Within strain, JB197 cultured at 29 °C vs 37 °C identified 529 DE proteins, while HB203 identified 524 DE proteins. Investigating differential protein profiles provide insights into strain specific behaviors with implications for better understanding host-pathogen interactions, disease transmission, and response to environmental conditions which can contribute to vaccine development, diagnostic improvement, and ultimately leptospirosis control. SIGNIFICANCE: Leptospirosis is a devastating zoonotic disease affecting humans, wild and domestic animals around the globe. Different species and serovars of Leptospira can affect various animal host species differently; for instance, a serovar that is asymptomatic in the rat may cause severe disease in a dog or human. These differences in host response are not only found at the species and serovar level for Leptospira, but also at the strain level. A prime example comes from strains JB197 and HB203, both species L. borgpetersenii, both serovar Hardjo. Interestingly, JB197 causes a severe acute infection in the hamster while HB203 causes an asymptomatic chronic infection. Understanding these unique relationships between pathogen and host species is important, especially in the context of prevention technologies such as vaccine design, where the strain of Leptospira used as a bacterin might have different efficiencies in different hosts. In this study, proteomic profiles of strains JB197 and HB203 were analyzed, and results revealed diverse protein expression profiles of outer membrane proteins, as well as proteins functioning in motility and growth.
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Affiliation(s)
- Ellie J Putz
- Infectious Bacterial Disease Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, IA, USA.
| | - Luis G V Fernandes
- Infectious Bacterial Disease Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, IA, USA
| | - Kaitlyn M Sarlo Davila
- Infectious Bacterial Disease Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, IA, USA
| | - Julian Whitelegge
- The Pasarow Mass Spectrometry Laboratory, David Geffen School of Medicine, NPI-Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, Los Angeles, CA, United States
| | - John D Lippolis
- Ruminant Diseases and Immunology Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, IA, USA
| | - Jarlath E Nally
- Infectious Bacterial Disease Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, IA, USA
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Sarlo Davila KM, Boggiatto P, Olsen S, Lippolis JD, Crooker BA, Putz EJ. Effect of selection genotype on immune response to Brucella abortus RB51 in Holstein cattle. Anim Genet 2024; 55:47-54. [PMID: 37946616 DOI: 10.1111/age.13372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 09/11/2023] [Accepted: 10/16/2023] [Indexed: 11/12/2023]
Abstract
Genetic selection for milk production traits in US Holsteins has affected numerous genes associated with reproduction and immunity. This study compares the transcriptomic response of peripheral blood mononuclear cells to an in vitro Brucella abortus strain RB51 (RB51) bacterial challenge between contemporary Holsteins and Holsteins that have not been selected for milk production traits since the mid-1960s. Total RNA was extracted from peripheral blood mononuclear cells from four contemporary and four unselected lactating, primiparous cows following 24-h incubation with or without stimulation with RB51 bacteria. RNA was sequenced and reads analyzed using tools from galaxy.scinet.usda.gov. A total of 412 differentially expressed genes (false discovery rate p < 0.05, log fold change > |1|) were identified. The upregulated genes (genes with higher expression in contemporary than unselected cattle) were enriched for 19 terms/pathways, including alanine, aspartate, and glutamate metabolism, indicating a cellular stress response. Downregulated genes (genes with higher expression in unselected than contemporary cows) were enriched for 37 terms/pathways, representing diverse immune responses, including natural killer cell-mediated immunity, interferon-γ production, negative regulation of interleukin-10 production, and cytokine receptor activity indicating a broad immune response with an emphasis on immune defense. These results provide evidence that differences exist between the two genotypes in response to in vitro bacterial challenge. This suggests that contemporary cows, genetically selected for milk production, may have reduced immune function, including limitations in response to intracellular bacteria.
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Affiliation(s)
- Kaitlyn M Sarlo Davila
- Infectious Bacterial Diseases Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, USA
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, USA
| | - Paola Boggiatto
- Infectious Bacterial Diseases Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, USA
| | - Steven Olsen
- Infectious Bacterial Diseases Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, USA
| | - John D Lippolis
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, USA
| | - Brian A Crooker
- Department of Animal Science, University of Minnesota, St. Paul, Minnesota, USA
| | - Ellie J Putz
- Infectious Bacterial Diseases Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, USA
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Xu R, Prakoso D, Salvador LCM, Rajeev S. Leptospira transcriptome sequencing using long-read technology reveals unannotated transcripts and potential polyadenylation of RNA molecules. Microbiol Spectr 2023; 11:e0223423. [PMID: 37861327 PMCID: PMC10715090 DOI: 10.1128/spectrum.02234-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 09/11/2023] [Indexed: 10/21/2023] Open
Abstract
IMPORTANCE Leptospirosis, caused by the spirochete bacteria Leptospira, is a zoonotic disease of humans and animals, accounting for over 1 million annual human cases and over 60,000 deaths. We have characterized operon transcriptional units, identified novel RNA coding regions, and reported evidence of potential posttranscriptional polyadenylation in the Leptospira transcriptomes for the first time using Oxford Nanopore Technology RNA sequencing protocols. The newly identified RNA coding regions and operon transcriptional units were detected only in the pathogenic Leptospira transcriptomes, suggesting their significance in virulence-related functions. This article integrates bioinformatics, infectious diseases, microbiology, molecular biology, veterinary sciences, and public health. Given the current knowledge gap in the regulation of leptospiral pathogenicity, our findings offer valuable insights to researchers studying leptospiral pathogenicity and provide both a basis and a tool for researchers focusing on prokaryotic molecular studies for the understanding of RNA compositions and prokaryotic polyadenylation for their organisms of interest.
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Affiliation(s)
- Ruijie Xu
- Institute of Bioinformatics, University of Georgia, Athens, Georgia, USA
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, Georgia, USA
| | - Dhani Prakoso
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA
| | - Liliana C. M. Salvador
- Institute of Bioinformatics, University of Georgia, Athens, Georgia, USA
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, Georgia, USA
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA
| | - Sreekumari Rajeev
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA
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Kavela S, Vyas P, CP J, Kushwaha SK, Majumdar SS, Faisal SM. Use of an Integrated Multi-Omics Approach To Identify Molecular Mechanisms and Critical Factors Involved in the Pathogenesis of Leptospira. Microbiol Spectr 2023; 11:e0313522. [PMID: 36853003 PMCID: PMC10100824 DOI: 10.1128/spectrum.03135-22] [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: 08/10/2022] [Accepted: 02/06/2023] [Indexed: 03/01/2023] Open
Abstract
Leptospirosis, a bacterial zoonosis caused by pathogenic Leptospira spp., is prevalent worldwide and has become a serious threat in recent years. Limited understanding of Leptospira pathogenesis and host response has hampered the development of effective vaccine and diagnostics. Although Leptospira is phagocytosed by innate immune cells, it resists its destruction, and the evading mechanism involved is unclear. In the present study, we used an integrative multi-omics approach to identify the critical molecular factors of Leptospira involved in pathogenesis during interaction with human macrophages. Transcriptomic and proteomic analyses were performed at 24 h postinfection of human macrophages (phorbol-12-myristate-13-acetate differentiated THP-1 cells) with the pathogenic Leptospira interrogans serovar Icterohaemorrhagiae strain RGA (LEPIRGA). Our results identified a total of 1,528 transcripts and 871 proteins that were significantly expressed with an adjusted P value of <0.05. The correlations between the transcriptomic and proteomic data were above average (r = 0.844), suggesting the role of the posttranscriptional processes during host interaction. The conjoint analysis revealed the expression of several virulence-associated proteins such as adhesins, invasins, and secretory and chemotaxis proteins that might be involved in various processes of attachment and invasion and as effectors during pathogenesis in the host. Further, the interaction of bacteria with the host cell (macrophages) was a major factor in the differential expression of these proteins. Finally, eight common differentially expressed RNA-protein pairs, predicted as virulent, outer membrane/extracellular proteins were validated by quantitative PCR. This is the first report using integrated multi-omics approach to identify critical factors involved in Leptospira pathogenesis. Validation of these critical factors may lead to the identification of target antigens for the development of improved diagnostics and vaccines against leptospirosis. IMPORTANCE Leptospirosis is a zoonotic disease of global importance. It is caused by a Gram-negative bacterial spirochete of the genus Leptospira. The current challenge is to detect the infection at early stage for treatment or to develop potent vaccines that can induce cross-protection against various pathogenic serovars. Understanding host-pathogen interactions is important to identify the critical factors involved in pathogenesis and host defense for developing improved vaccines and diagnostics. Utilizing an integrated multi-omics approach, our study provides important insight into the interaction of Leptospira with human macrophages and identifies a few critical factors (such as virulence-associated proteins) involved in pathogenesis. These factors can be exploited for the development of novel tools for the detection, treatment, or prevention of leptospirosis.
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Affiliation(s)
- Sridhar Kavela
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad, India
| | - Pallavi Vyas
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad, India
- Regional Centre for Biotechnology, Faridabad, India
| | - Jusail CP
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad, India
- Regional Centre for Biotechnology, Faridabad, India
| | - Sandeep K. Kushwaha
- Bioinformatics Lab, National Institute of Animal Biotechnology, Hyderabad, India
| | - Subeer S. Majumdar
- Gene and Protein Engineering Lab, National Institute of Animal Biotechnology, Hyderabad, India
| | - Syed M. Faisal
- Laboratory of Vaccine Immunology, National Institute of Animal Biotechnology, Hyderabad, India
- Regional Centre for Biotechnology, Faridabad, India
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Cheah HL, Ahmed SA, Tang TH. Transcription start site mapping and small RNA profiling of Leptospira biflexa serovar Patoc. World J Microbiol Biotechnol 2023; 39:104. [PMID: 36808011 DOI: 10.1007/s11274-023-03540-4] [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: 11/01/2022] [Accepted: 02/03/2023] [Indexed: 02/23/2023]
Abstract
Leptospirosis is an emerging zoonotic disease caused by bacterial species of the genus Leptospira. However, the regulatory mechanisms and pathways underlying the adaptation of pathogenic and non-pathogenic Leptospira spp. in different environmental conditions remain elusive. Leptospira biflexa is a non-pathogenic species of Leptospira that lives exclusively in a natural environment. It is an ideal model not only for exploring molecular mechanisms underlying the environmental survival of Leptospira species but also for identifying virulence factors unique to Leptospira's pathogenic species. In this study, we aim to establish the transcription start site (TSS) landscape and the small RNA (sRNA) profile of L. biflexa serovar Patoc grown to exponential and stationary phases via differential RNA-seq (dRNA-seq) and small RNA-seq (sRNA-seq) analyses, respectively. Our dRNA-seq analysis uncovered a total of 2726 TSSs, which are also used to identify other elements, e.g., promoter and untranslated regions (UTRs). Besides, our sRNA-seq analysis revealed a total of 603 sRNA candidates, comprising 16 promoter-associated sRNAs, 184 5'UTR-derived sRNAs, 230 true intergenic sRNAs, 136 5'UTR-antisense sRNAs, and 130 open reading frame (ORF)-antisense sRNAs. In summary, these findings reflect the transcriptional complexity of L. biflexa serovar Patoc under different growth conditions and help to facilitate our understanding of regulatory networks in L. biflexa. To the best of our knowledge, this is the first study reporting the TSS landscape of L. biflexa. The TSS and sRNA landscapes of L. biflexa can also be compared with its pathogenic counterparts, e.g., L. borgpetersenii and L. interrogans, to identify features contributing to their environmental survival and virulence.
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Affiliation(s)
- Hong-Leong Cheah
- Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, 13200, Kepala Batas, Penang, Malaysia
| | - Siti Aminah Ahmed
- Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, 13200, Kepala Batas, Penang, Malaysia
| | - Thean-Hock Tang
- Advanced Medical & Dental Institute (AMDI), Universiti Sains Malaysia, Bertam, 13200, Kepala Batas, Penang, Malaysia.
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Vieira DS, Chaurasia R, Vinetz JM. Comparison of the PF07598-Encoded Virulence-Modifying Proteins of L. interrogans and L. borgpetersenii. Trop Med Infect Dis 2022; 8:14. [PMID: 36668921 PMCID: PMC9863803 DOI: 10.3390/tropicalmed8010014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 12/28/2022] Open
Abstract
Leptospirosis is an emerging infectious disease, with increasing frequency and severity of outbreaks, a changing epidemiology of populations at risk, and the emergence of new strains, serovars, serogroups, and species. Virulence-modifying (VM) proteins encoded by the PF07598 gene family are hypothesized to be Leptospira-secreted exotoxins that mediate the molecular and cellular pathogenesis of severe and fatal leptospirosis. If confirmed experimentally, this concept could revolutionize the treatment, diagnosis, prognosis, and vaccine-mediated prevention of leptospirosis by enabling a novel array of targeted interventions. VM proteins, as with other bacterial-secreted protein exotoxins, mediate their virulence effects by attaching to eukaryotic cells, competing with other microorganisms for limited resources in environmental niches, directly intoxicating target cells, and disrupting their function in the mammalian host. In contrast with the most pathogenic group of Lept ospira, particularly L. interrogans, whose genomes contain 12-15 PF07598 paralogs, strains of the livestock and human pathogen L. borgpetersenii have two PF07598 paralogs. Given the possible non-environmentally mediated transmission of some L. borgpetersenii strains and the much smaller number of VM proteins in this species, their role in infection and disease may well differ from other leptospiral species. Comparison of VM proteins from different clades of pathogenic Leptospira may deepen our understanding of leptospirosis's pathogenesis, leading to novel approaches to ameliorating Leptospira infection in humans and animals.
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Affiliation(s)
| | | | - Joseph M. Vinetz
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06510, USA
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Lauretti-Ferreira F, Teixeira AAR, Giordano RJ, da Silva JB, Abreu PAE, Barbosa AS, Akamatsu MA, Ho PL. Characterization of a virulence-modifying protein of Leptospira interrogans identified by shotgun phage display. Front Microbiol 2022; 13:1051698. [PMID: 36519163 PMCID: PMC9742253 DOI: 10.3389/fmicb.2022.1051698] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 11/08/2022] [Indexed: 09/02/2023] Open
Abstract
Pathogenic species of Leptospira are etiologic agents of leptospirosis, an emerging zoonotic disease of worldwide extent and endemic in tropical regions. The growing number of identified leptospiral species sheds light to their genetic diversity and unique virulence mechanisms, many of them still remain unknown. Toxins and adhesins are important virulence factors in several pathogens, constituting promising antigens for the development of vaccines with cross-protection and long-lasting effect against leptospirosis. For this aim, we used the shotgun phage display technique to unravel new proteins with adhesive properties. A shotgun library was constructed using fragmented genomic DNA from Leptospira interrogans serovar Copenhageni strain Fiocruz L1-130 and pG8SAET phagemid vector. Selection of phages bearing new possible cell-binding antigens was performed against VERO cells, using BRASIL biopanning methodology. Analysis of selected clones revealed the hypothetical protein LIC10778, a potentially exposed virulence factor that belongs to the virulence-modifying (VM) protein family (PF07598), composed of 13 members in the leptospiral strain Fiocruz L1-130. Prediction of LIC10778 tertiary structure indicates that the protein contains a cellular-binding domain (N-terminal portion) and an unknown domain of no assigned activity (C-terminal portion). The predicted N-terminal domain shared structural similarities with the cell-binding and internalization domain of toxins like Ricin and Abrin, as well as to the Community-Acquired Respiratory Distress Syndrome (CARDS) toxin in Mycoplasma pneumoniae. Interestingly, recombinant portions of the N-terminal region of LIC10778 protein showed binding to laminin, collagens I and IV, vitronectin, and plasma and cell fibronectins using overlay blotting technique, especially regarding the binding site identified by phage display. These data validate our preliminary phage display biopanning and support the predicted three-dimensional models of LIC10778 protein and other members of PF07598 protein family, confirming the identification of the N-terminal cell-binding domains that are similar to ricin-like toxins. Moreover, fluorescent fused proteins also confirmed that N-terminal region of LIC10778 is capable of binding to VERO and A549 cell lines, further highlighting its virulence role during host-pathogen interaction in leptospirosis probably mediated by its C-terminal domain. Indeed, recent results in the literature confirmed this assumption by demonstrating the cytotoxicity of a closely related PF07598 member.
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Affiliation(s)
- Fabiana Lauretti-Ferreira
- Bioindustrial Division, Butantan Institute, São Paulo, Brazil
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | | | - Ricardo José Giordano
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | | | | | | | | | - Paulo Lee Ho
- Bioindustrial Division, Butantan Institute, São Paulo, Brazil
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
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9
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Some like it hot, some like it cold; proteome comparison of Leptospira borgpetersenii serovar Hardjo strains propagated at different temperatures. J Proteomics 2022; 262:104602. [DOI: 10.1016/j.jprot.2022.104602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/31/2022] [Accepted: 04/29/2022] [Indexed: 11/22/2022]
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Putz EJ, Andreasen CB, Stasko JA, Fernandes LGV, Palmer MV, Rauh MJ, Nally JE. Circulating Foamy Macrophages in the Golden Syrian Hamster (Mesocricetus auratus) Model of Leptospirosis. J Comp Pathol 2021; 189:98-109. [PMID: 34886992 DOI: 10.1016/j.jcpa.2021.10.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/14/2021] [Accepted: 10/15/2021] [Indexed: 12/21/2022]
Abstract
Leptospirosis is a world-wide zoonotic disease caused by pathogenic Leptospira and can be asymptomatic or can cause clinical signs ranging from influenza-like to multi-organ failure and death in severe cases. While species and strain specificity can play a major role in disease presentation, the hamster is susceptible to most leptospiral infections and is the model of choice for vaccine efficacy testing. During evaluation of blood smears from hamsters challenged with different species and strains of Leptospira, a circulating population of large, mononuclear, lipid-filled cells, most similar to foamy macrophages (FMs), was detected. Circulating FMs were identified by Giemsa staining and verified by scanning and transmission electron microscopy. FMs were found in the circulating blood of all Leptospira-challenged hamsters, indicating that the finding was not species or strain specific, although higher numbers of FMs tended to correlate with severity of disease. The unique finding of circulating FMs in the hamster model of leptospirosis can yield additional insights into the pathogenesis of leptospirosis and other diseases that induce circulating FMs.
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Affiliation(s)
- Ellie J Putz
- Infectious Bacterial Diseases Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, Iowa, USA.
| | - Claire B Andreasen
- Department of Veterinary Pathology, College of Veterinary Medicine, Ames, Iowa, USA
| | - Judith A Stasko
- Infectious Bacterial Diseases Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, Iowa, USA
| | - Luis G V Fernandes
- Infectious Bacterial Diseases Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, Iowa, USA; Laboratório de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, Brazil
| | - Mitchell V Palmer
- Infectious Bacterial Diseases Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, Iowa, USA
| | - Michael J Rauh
- Department of Pathology & Molecular Medicine, Queen's University, Kingston, Ontario, Canada
| | - Jarlath E Nally
- Infectious Bacterial Diseases Research Unit, USDA Agriculture Research Service, National Animal Disease Center, Ames, Iowa, USA
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