Computer aided subunit vaccine design against pathogenic Leptospira serovars (original) (raw)

Designing of multiepitope-based vaccine against Leptospirosis using Immuno-Informatics approaches

2021

Leptospira is a zoonotic pathogen causing significant morbidity and mortality both in animals and humans. Although several surface proteins have been identified as vaccine candidate, they failed to induce sterilizing immunity and cross protection against different serovars. Thus, identification of highly immunogenic antigens that are conserved among pathogenic serovars would be first step towards development of universal vaccine for Leptospirosis. Here we used reverse vaccinology pipeline to screen core genome of pathogenic Leptospira spp.in order to identify suitable vaccine candidates. Based on properties like sub cellular localization, adhesin, homology to human proteins, antigenicity and allergenicity, 18 antigenic proteins were identified and were further investigated for immunological properties. Based on immunogenicity, Protegenicity, Antigenicity, B-cell and promiscuous T-cell epitopes, 6 Potential Vaccine Candidates (PVCs) were finally selected which covered most of the aff...

In Silico B Cell and T Cell Epitopes Evaluation of lipL32 and OmpL1 Proteins for Designing a Recombinant Multi-Epitope Vaccine Against Leptospirosis

International Journal of Infection

Leptospirosis is a widespread zoonotic disease caused by Leptospira interrogans. The conventional vaccines have some major problems. Therefore, recombinant vaccines such as multiple-epitope vaccine are suggested. OmpL1 and lipL32 are the most important proteins of Leptospira interrogans bacteria that can be used in epitope prediction process to design a multiple-epitope vaccine. Hence, in this study, the most reliable and accurate online servers were applied to predict B cell and T cell epitopes, the secondary and tertiary structures, enzyme digestion, and antigenicity score of ompL1 and lipL32. The results showed that epitopes located at 103-122, 210-232, and 272-291 amino acid residues are the common epitopes between T cell (MHCI) and B cell. 288-308 amino acid residues were introduced as common epitopes to stimulate both T cell (MHCI and MHCII) and B cell of ompL1 protein. In the case of LipL32 protein, 80-96 amino acid residues are recommended for T cell epitopes and 63-81 amino acid residues for stimulation of both B and T cells. All the mentioned epitopes can be considered as linear epitopes in designing a recombinant vaccine based on chimeric epitopes. It appears that these epitopes can be applied to design recombinant multiple-epitope vaccines against leptospirosis.

Challenges for the development of a universal vaccine against leptospirosis revealed by the evaluation of 22 vaccine candidates

Frontiers in Cellular and Infection Microbiology

Leptospirosis is a neglected disease of man and animals that affects nearly half a million people annually and causes considerable economic losses. Current human vaccines are inactivated whole-cell preparations (bacterins) of Leptospira spp. that provide strong homologous protection yet fail to induce a cross-protective immune response. Yearly boosters are required, and serious side-effects are frequently reported so the vaccine is licensed for use in humans in only a handful of countries. Novel universal vaccines require identification of conserved surface-exposed epitopes of leptospiral antigens. Outer membrane β-barrel proteins (βb-OMPs) meet these requirements and have been successfully used as vaccines for other diseases. We report the evaluation of 22 constructs containing protein fragments from 33 leptospiral βb-OMPs, previously identified by reverse and structural vaccinology and cell-surface immunoprecipitation. Three-dimensional structures for each leptospiral βb-OMP were ...

Discovery of Novel Leptospirosis Vaccine Candidates Using Reverse and Structural Vaccinology

Frontiers in immunology, 2017

Leptospira spp. are diderm (two membranes) bacteria that infect mammals causing leptospirosis, a public health problem with global implications. Thousands of people die every year due to leptospirosis, especially in developing countries with tropical climates. Prophylaxis is difficult due to multiple factors, including the large number of asymptomatic hosts that transmit the bacteria, poor sanitation, increasing numbers of slum dwellers, and the lack of an effective vaccine. Several leptospiral recombinant antigens were evaluated as a replacement for the inactivated (bacterin) vaccine; however, success has been limited. A prospective vaccine candidate is likely to be a surface-related protein that can stimulate the host immune response to clear leptospires from blood and organs. In this study, a comprehensive bioinformatics approach based on reverse and structural vaccinology was applied toward the discovery of novel leptospiral vaccine candidates. The Leptospira interrogans serovar...

Exploring Leptospiral proteomes to identify potential candidates for vaccine design against Leptospirosis using an immunoinformatics approach

Scientific reports, 2018

Leptospirosis is the most widespread zoonotic disease, estimated to cause severe infection in more than one million people each year, particularly in developing countries of tropical areas. Several factors such as variable and nonspecific clinical manifestation, existence of large number of serovars and asymptomatic hosts spreading infection, poor sanitation and lack of an effective vaccine make prophylaxis difficult. Consequently, there is an urgent need to develop an effective vaccine to halt its spread all over the world. In this study, an immunoinformatics approach was employed to identify the most vital and effective immunogenic protein from the proteome of Leptospira interrogans serovar Copenhageni strain L1-130 that may be suitable to stimulate a significant immune response aiding in the development of peptide vaccine against leptospirosis. Both B-cell and T-cell (Helper T-lymphocyte (HTL) and cytotoxic T lymphocyte (CTL)) epitopes were predicted for the conserved and most im...

Immuno-informatics based approaches to design a novel multi epitope-based vaccine for immune response reinforcement against Leptospirosis

Molecular Immunology, 2018

Leptospirosis is known as a zoonotic disease of global importance originated from infection with the spirochete bacterium Leptospira. Although several leptospirosis vaccines have been tested, the vaccination is relatively unsuccessful in clinical application despite decades of research. Therefore, this study was conducted to construct a novel multi-epitope based vaccine against leptospirosis by using Hap1, LigA, LAg42, SphH and HSP58 antigens. T cell and IFN gamma epitopes were predicted from these antigens. In addition, to induce strong CD4 + helper T lymphocytes (HTLs) responses, Pan HLA DR-binding epitope (PADRE) and helper epitopes selected from Tetanus toxin fragment C (TTFrC) were applied. Moreover, for boosting immune response, Heparin-Binding Hemagglutinin (HBHA), a novel TLR4 agonist was added to the construct as an adjuvant. Finally, selected epitopes were linked together using EAAAK, GPGPG, AAY and HEYGAEALERAG linkers. Based on the predicted epitopes, a multi-epitope vaccine was construct with 490 amino acids. Physico-chemical properties, secondary and tertiary structures, stability, intrinsic protein disorder, solubility, and allergenicity of this vaccine construct were assessed by applying immunoinformatics analyses. A soluble, and non-allergic protein with a molecular weight of 53.476 kDa was obtained. Further analyses validated the stability of the chimeric protein and the predicted epitopes in the chimeric vaccine indicated strong potential to induce B-cell and T-cell mediated immune response. Therefore, immunoinformatics analysis showed that the modeled multi-epitope vaccine can properly stimulate the both T and B cells immune responses and could potentially be used for prophylactic or therapeutic usages.

Subunit Approach to Evaluation of the Immune Protective Potential of Leptospiral Antigens

Clinical and Vaccine Immunology, 2011

Leptospirosis is the most widespread zoonosis in the world. Current vaccines are based on whole-cell preparations that cause severe side effects and do not induce satisfactory immunity. In light of the leptospiral genome sequences recently made available, several studies aimed at identification of protective recombinant immunogens have been performed; however, few such immunogens have been identified. The aim of this study was to evaluate 27 recombinant antigens to determine their potential to induce an immune response protective against leptospirosis in the hamster model. Experiments were conducted with groups of female hamsters immunized with individual antigen preparations. Hamsters were then challenged with a lethal dose of Leptospira interrogans. Thirteen antigens induced protective immune responses; however, only recombinant proteins LIC10325 and LIC13059 induced significant protection against mortality. These results have important implications for the development of an efficacious recombinant subunit vaccine against leptospirosis.

Leptospirosis Vaccine: Search for Subunit Candidates

Procedia in Vaccinology, 2009

Subunit vaccines are a potential intervention strategy against leptospirosis, which is a major public health problem in developing countries. Thus far, several proteins have been evaluated as potential vaccine candidates, but all those tested in aluminum hydroxide adjuvant have failed to protect animals against lethal challenge. Seven new leptospiral lipoproteins were evaluated as vaccine candidates. The coding sequences of these lipoproteins were amplified by PCR from Leptospira interrogans serovar Copenhageni, strain Fiocruz L1-130, cloned and expressed in Escherichia coli. The purified proteins were adsorbed in aluminum adjuvant and used in the immunization of four to six weeks old hamsters. After two doses of 60 g of recombinant protein, hamsters were challenged with a lethal dose of L. interrogans. All seven tested proteins failed to fully protect the animals from disease or death. Further study must be undertaken toward developing an efficient subunit vaccine against leptospirosis for humans, livestock and pets.

Evaluation of the Leptospira interrogans Outer Membrane Protein OmpL37 as a Vaccine Candidate

PloS one, 2015

The identification of potential vaccine candidates against leptospirosis remains a challenge. However, one such candidate is OmpL37, a potentially surface-exposed antigen that has the highest elastin-binding ability described to date, suggesting that it plays an important role in host colonization. In order to evaluate OmpL37's ability to induce a protective immune response, prime-boost, DNA and subunit vaccine strategies were tested in the hamster model of lethal leptospirosis. The humoral immune response was evaluated using an indirect ELISA test, and the cytokine profile in whole blood was determined by quantitative real-time PCR. Unlike the DNA vaccine, the administration of recombinant OmpL37 induced a strong IgG antibody response. When individually administrated, both formulations stimulated a TNF-α mediated inflammatory response. However, none of the OmpL37 formulations or vaccination strategies induced protective immunity. Further studies are required towards the identif...

Whole-genome analysis of Leptospira interrogans to identify potential vaccine candidates against leptospirosis

Fems Microbiology Letters, 2005

Leptospirosis is an important global human and veterinary health problem. Humans can be infected by exposure to chronically infected animals and their environment. An important focus of the current leptospiral research is the identification of outer membrane proteins (OMPs). Due to their location, leptospiral OMPs are likely to be relevant in host-pathogen interactions, hence their potential ability to stimulate heterologous immunity. The existing whole-genome sequence of Leptospira interrogans serovar Copenhageni offers a unique opportunity to search for cell surface proteins. Predicted genes encoding potential surface proteins were amplified from genomic DNA by PCR methodology and cloned into an Escherichia coli expression system. The partially purified recombinant proteins were probed by Western blotting with sera from human patients diagnosed with leptospirosis. Sixteen proteins, out of a hundred tested, were recognized by antibodies present in human sera. Four of these proteins were conserved among eight serovars of L. interrogans and absent in the non-pathogenic Leptospira biflexa. These proteins might be useful for the diagnosis of the disease as well as potential vaccine candidates.