1
|
Azevedo IR, Amamura TA, Isaac L. Human leptospirosis: In search for a better vaccine. Scand J Immunol 2023; 98:e13316. [PMID: 39008520 DOI: 10.1111/sji.13316] [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: 12/22/2022] [Revised: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 07/17/2024]
Abstract
Leptospirosis is a neglected disease caused by bacteria of the genus Leptospira and is more prevalent in tropical and subtropical countries. This pathogen infects humans and other animals, responsible for the most widespread zoonosis in the world, estimated to be responsible for 60 000 deaths and 1 million cases per year. To date, commercial vaccines against human leptospirosis are available only in some countries such as Japan, China, Cuba and France. These vaccines prepared with inactivated Leptospira (bacterins) induce a short-term and serovar-specific immune response, with strong adverse side effects. To circumvent these limitations, several research groups are investigating new experimental vaccines in order to ensure that they are safe, efficient, and protect against several pathogenic Leptospira serovars, inducing sterilizing immunity. Most of these protocols use attenuated cultures, preparations after LPS removal, recombinant proteins or DNA from pathogenic Leptospira spp. The aim of this review was to highlight several promising vaccine candidates, considering their immunogenicity, presence in different pathogenic Leptospira serovars, their role in virulence or immune evasion and other factors.
Collapse
Affiliation(s)
- Isabela Resende Azevedo
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Thais Akemi Amamura
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Lourdes Isaac
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
2
|
Alves da Silva PYO, Midon LM, Heinemann MB, de Moraes Vasconcelos D, Barbosa AS, Isaac L. Contribution of Complement System pathways to the killing of Leptospira spp. Microbes Infect 2020; 22:550-557. [PMID: 32730816 DOI: 10.1016/j.micinf.2020.07.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 06/23/2020] [Accepted: 07/19/2020] [Indexed: 01/26/2023]
Abstract
The Complement System (CS) plays an important role in the immune response against leptospirosis and can be activated by the Alternative and Lectin Pathways (Innate Immunity) and by the Classical Pathway (Acquired Immunity). Here we analyzed a broad range of nonpathogenic and pathogenic Leptospira strains considering their interaction with each CS pathway. We determined bacterial survival rate and CS protein deposition in the presence of purified proteins, specific component depleted sera and NHS treated with the chelating agents EDTA (inhibits all three activation pathways) or EGTA (inhibits the Classical and Lectin Pathways). We suggest that the Lectin and the Alternative Pathways have an important role to eliminate saprophytic leptospires since i) approximately 50% survival of both saprophytic strains was observed in the presence of MBL-deficient serum; ii) approximately 50% survival of Leptospira biflexa Patoc I was observed in the presence of NHS - EGTA and iii) C1q-depleted serum caused significant bacterial lysis. In all serovars investigated the deposition of C5-C9 proteins on saprophytic Leptospira strains was more pronounced when compared to pathogenic species confirming previous studies in the literature. No difference on C3 deposition was observed between nonpathogenic and pathogenic strains. In conclusion, Leptospira strains interact to different degrees with CS proteins, especially those necessary to form MAC, indicating that some strains and specific ligands could favor the binding of certain CS proteins.
Collapse
Affiliation(s)
| | - Leonardo Moura Midon
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, Brazil
| | | | | | | | - Lourdes Isaac
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, Brazil.
| |
Collapse
|
3
|
Barbosa AS, Isaac L. Strategies used by Leptospira spirochetes to evade the host complement system. FEBS Lett 2020; 594:2633-2644. [PMID: 32153015 DOI: 10.1002/1873-3468.13768] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/27/2020] [Accepted: 02/28/2020] [Indexed: 12/19/2022]
Abstract
Leptospires are highly invasive spirochetes equipped with efficient strategies for dissemination in the host. The Leptospira genus currently comprises 64 species divided into two major clades: the saprophytes composed of nonpathogenic, free-living organisms, and the pathogens encompassing all the species that cause mild or severe infections in humans and animals. While saprophytes are highly susceptible to the lytic action of the complement system, pathogenic (virulent) strains have evolved virulence strategies that allow efficient colonization of a variety of hosts and target organs, including mechanisms to circumvent hosts' innate and acquired immune responses. Pathogenic Leptospira avoid complement-mediated killing by recruiting host complement regulatory proteins and by targeting complement proteins using own and host-expressed proteases. This review outlines the role of complement in eradicating saprophytic Leptospira and the stratagems adopted by pathogenic Leptospira to maneuver the host complement system for their benefit.
Collapse
Affiliation(s)
| | - Lourdes Isaac
- Laboratory of Complement, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, Brazil
| |
Collapse
|
4
|
Lubbers R, Sutherland JS, Goletti D, de Paus RA, Dijkstra DJ, van Moorsel CHM, Veltkamp M, Vestjens SMT, Bos WJW, Petrone L, Malherbe ST, Walzl G, Gelderman KA, Groeneveld GH, Geluk A, Ottenhoff THM, Joosten SA, Trouw LA. Expression and production of the SERPING1-encoded endogenous complement regulator C1-inhibitor in multiple cohorts of tuberculosis patients. Mol Immunol 2020; 120:187-195. [PMID: 32179338 DOI: 10.1016/j.molimm.2020.02.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 02/03/2020] [Accepted: 02/10/2020] [Indexed: 01/04/2023]
Abstract
BACKGROUND To facilitate better discrimination between patients with active tuberculosis (TB) and latent TB infection (LTBI), whole blood transcriptomic studies have been performed to identify novel candidate host biomarkers. SERPING1, which encodes C1-inhibitor (C1-INH), the natural inhibitor of the C1-complex has emerged as candidate biomarker. Here we collated and analysed SERPING1 expression data and subsequently determined C1-INH protein levels in four cohorts of patients with TB. METHODS SERPING1 expression data were extracted from online deposited datasets. C1-INH protein levels were determined by ELISA in sera from individuals with active TB, LTBI as well as other disease controls in geographically diverse cohorts. FINDINGS SERPING1 expression was increased in patients with active TB compared to healthy controls (8/11 cohorts), LTBI (13/14 cohorts) and patients with other (non-TB) lung-diseases (7/7 cohorts). Serum levels of C1-INH were significantly increased in The Gambia and Italy in patients with active TB relative to the endemic controls but not in South Africa or Korea. In the largest cohort (n = 50), with samples collected longitudinally, normalization of C1-INH levels following successful TB treatment was observed. This cohort, also showed the most abundant increase in C1-INH, and a positive correlation between C1q and C1-INH levels. Combined presence of increased levels of both C1q and C1-INH had high specificity for active TB (96 %) but only very modest sensitivity 38 % compared to the endemic controls. INTERPRETATION SERPING1 transcript expression is increased in TB patients, while serum protein levels of C1-INH were increased in half of the cohorts analysed.
Collapse
Affiliation(s)
- Rosalie Lubbers
- Department of Rheumatology, Leiden University Medical Center, Leiden, the Netherlands
| | - Jayne S Sutherland
- Vaccines and Immunity Theme, Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | - Delia Goletti
- Translational Research Unit, Department of Epidemiology and Preclinical Research, National Institute for Infectious Diseases L. Spallanzani-IRCCS, Rome, Italy
| | - Roelof A de Paus
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, the Netherlands
| | - Douwe J Dijkstra
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, the Netherlands
| | | | - Marcel Veltkamp
- Department of Pulmonology, St. Antonius Hospital, Nieuwegein, the Netherlands
| | - Stefan M T Vestjens
- Department of Internal Medicine, St. Antonius Hospital, Nieuwegein, the Netherlands
| | - Willem J W Bos
- Department of Internal Medicine, St. Antonius Hospital, Nieuwegein, the Netherlands; Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Linda Petrone
- Translational Research Unit, Department of Epidemiology and Preclinical Research, National Institute for Infectious Diseases L. Spallanzani-IRCCS, Rome, Italy
| | - Stephanus T Malherbe
- DST/NRF Centre of Excellence for Biomedical TB Research and SAMRC Centre for TB Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Gerhard Walzl
- DST/NRF Centre of Excellence for Biomedical TB Research and SAMRC Centre for TB Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | | | - Geert H Groeneveld
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, the Netherlands
| | - Annemieke Geluk
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, the Netherlands
| | - Tom H M Ottenhoff
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, the Netherlands
| | - Simone A Joosten
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, the Netherlands
| | - Leendert A Trouw
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, the Netherlands.
| |
Collapse
|