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Vaghasia V, Lata KS, Patel S, Das J. Epitopes mapping for identification of potential cross-reactive peptide against leptospirosis. J Biomol Struct Dyn 2023:1-16. [PMID: 37948196 DOI: 10.1080/07391102.2023.2279285] [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: 05/29/2023] [Accepted: 10/30/2023] [Indexed: 11/12/2023]
Abstract
Leptospira, the pathogenic helical spirochetes that cause leptospirosis, is an emerging zoonotic disease with effective dissemination tactics in the host and can infect humans and animals with moderate or severe illnesses. Thus, peptide-based vaccines may be the most effective strategy to manage the immune response against Leptospira to close these gaps. In the current investigation, highly immunogenic proteins from the proteome of Leptospira interorgan serogroup Icterohaemorrhagie serovar Lai strain 56601 were identified using immunoinformatic methods. It was discovered that the conserved and most immunogenic outer membrane Lepin protein was both antigenic and non-allergenic by testing 15 linear B-cells and the ten best T-cell (Helper-lymphocyte (HTL) with the most significant number of HLA-DR binding alleles and the eight cytotoxic T lymphocyte (CTL)) epitopes. Furthermore, a 3D structural model of CTL epitopes was created using the Pep-Fold3 platform. Using the Autodock 4.2 docking server, research was conducted to determine how well the top-ranked CTL peptide models attach to HLA-A*0201 (PDB ID: 4U6Y). With HLA-A*0201, the epitope SSGTGNLHV binds with a binding energy of -1.29 kcal/mol. Utilizing molecular dynamics modeling, the projected epitope-allele docked complex structure was optimized, and the stability of the complex system was assessed. Therefore, this epitope can trigger an immunological response and produce effective Leptospira vaccine candidates. Overall, this study offers a unique vaccination candidate and may encourage additional research into leptospirosis vaccines.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Vibhisha Vaghasia
- Department of Botany, Bioinformatics and Climate Change Impacts management, Gujarat University, Ahmedabad, India
| | - Kumari Snehkant Lata
- Department of Botany, Bioinformatics and Climate Change Impacts management, Gujarat University, Ahmedabad, India
| | - Saumya Patel
- Department of Botany, Bioinformatics and Climate Change Impacts management, Gujarat University, Ahmedabad, India
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Mohammadzadeh Hosseini Moghri SAH, Ranjbar M, Hassannia H, Khakdan F. In silico analysis of the conserved surface-exposed epitopes to design novel multiepitope peptide vaccine for all variants of the SARS-CoV-2. J Biomol Struct Dyn 2023; 41:7603-7615. [PMID: 36124826 DOI: 10.1080/07391102.2022.2123395] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 09/04/2022] [Indexed: 10/14/2022]
Abstract
Recently the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a pervasive threat to generic health. The SARS-CoV-2 spike (S) glycoprotein plays a fundamental role in binds and fusion to the angiotensin-converting enzyme 2 (ACE2). The multi-epitope peptide vaccines would be able to elicit both long-lasting humoral and cellular immune responses, resulting the eliminating SARS-CoV-2 infections as asymptomatic patients are in large numbers. Recently, the omicron variant of the SARS-CoV-2 became a variant of concern that contained just 15-point mutations in the receptor-binding domain of the spike protein. In order to eliminate new evidence on coronavirus variants of concern detected through epidemic intelligence, the conserved epitopes of the receptor-binding domain (RBD) and spike cleavage site is the most probable target for vaccine development to inducing binds and fusion inhibitors neutralizing antibodies respectively. In this study, we utilized bioinformatics tools for identifying and analyzing the spike (S) glycoprotein sequence, e.g. the prediction of the potential linear B-cell epitopes, B-cell multi‑epitope design, secondary and tertiary structures, physicochemical properties, solubility, antigenicity, allergenicity, the molecular docking and molecular dynamics simulation for the promising vaccine candidate against all variant of concern of SARS-CoV-2. Among the epitopes of the RBD region are surface-exposed epitopes SVYAWNRKRISNCV and ATRFASVYAWNRKR as the conserved sequences in all variants of concern can be a good candidate to induce an immune response.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
| | - Mojtaba Ranjbar
- Microbial Biotechnology Department, Faculty of Biotechnology, Amol University of Special Modern Technologies, Amol, Islamic Republic of Iran
| | - Hadi Hassannia
- Immunogenetic Research Center, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
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Mohammadzadeh Hosseini Moghri SAH, Mahmoodi Chalbatani G, Ranjbar M, Raposo C, Abbasian A. CD171 Multi-epitope peptide design based on immuno-informatics approach as a cancer vaccine candidate for glioblastoma. J Biomol Struct Dyn 2023; 41:1028-1040. [PMID: 36617427 DOI: 10.1080/07391102.2021.2020166] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Glioblastoma (GB) is a common primary malignancy of the central nervous system, and one of the highly lethal brain tumors. GB cells can promote therapeutic resistance and tumor angiogenesis. The CD171 is an adhesion molecule in neuronal cells that is expressed in glioma cells as a regulator of brain development during the embryonic period. CD171 is one of the immunoglobulin-like CAMs (cell adhesion molecules) families that can be associated with prognosis in a variety of human tumors. The multi-epitope peptide vaccines are based on synthetic peptides with a combination of both B-cell epitopes and T-cell epitopes, which can induce specific humoral or cellular immune responses. Moreover, Cholera toxin subunit B (CTB), a novel TLR agonist was utilized in the final construct to polarize CD4+ T cells toward T-helper 1 to induce strong cytotoxic T lymphocytes (CTL) responses. In the present study, several immune-informatics tools were used for analyzing the CD171 sequence and studying the important characteristics of a designed vaccine. The results included molecular docking, molecular dynamics simulation, immune response simulation, prediction and validation of the secondary and tertiary structure, physicochemical properties, solubility, conservancy, toxicity as well as antigenicity and allergenicity of the promising candidate for a vaccine against CD171. The immuno-informatic analyze suggested 12 predicted multi-epitope peptides, whose construction consists of 582 residues long. Therewith, cloning adaptation of the designed vaccine was performed, and eventually sequence was inserted into pET30a (+) vector for the application of the anti-glioblastoma vaccine development.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
| | | | - Mojtaba Ranjbar
- Faculty of Biotechnology, Department of Microbial Biotechnology, Amol University of Special Modern Technologies, Amol, Iran
| | - Catarina Raposo
- Faculdade de Ciências Farmacêuticas, Universidade Estadual de Campinas (UNICAMP), Campinas, Brazil
| | - Arefeh Abbasian
- Faculty of Basic Sciences, Department of Biology, Semnan University, Semnan, Iran
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Saivish MV, Menezes GDL, da Costa VG, da Silva GCD, Marques RE, Nogueira ML, Silva RAD. Predicting Antigenic Peptides from Rocio Virus NS1 Protein for Immunodiagnostic Testing Using Immunoinformatics and Molecular Dynamics Simulation. Int J Mol Sci 2022; 23:7681. [PMID: 35887029 PMCID: PMC9322101 DOI: 10.3390/ijms23147681] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/02/2022] [Accepted: 07/06/2022] [Indexed: 12/10/2022] Open
Abstract
The mosquito-borne disease caused by the Rocio virus is a neglected threat, and new immune inputs for serological testing are urgently required for diagnosis in low-resource settings and epidemiological surveillance. We used in silico approaches to identify a specific antigenic peptide (p_ROCV2) in the NS1 protein of the Rocio virus that was theoretically predicted to be stable and exposed on its surface, where it demonstrated key properties allowing it to interact with antibodies. These findings related to the molecular dynamics of this peptide provide important insights for advancing diagnostic platforms and investigating therapeutic alternatives.
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Affiliation(s)
- Marielena Vogel Saivish
- Departamento de Doenças Dermatológicas, Infecciosas e Parasitárias, Faculdade de Medicina de São José do Rio Preto (FAMERP), São José do Rio Preto 15090-000, SP, Brazil; (M.V.S.); (G.C.D.d.S.)
- Laboratório Nacional de Biociências, Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas 13083-100, SP, Brazil;
| | - Gabriela de Lima Menezes
- Núcleo Colaborativo de Biosistemas, Universidade Federal de Jataí, Jataí 75801-615, GO, Brazil;
- Bioinformatics Multidisciplinary Environment, Programa de Pós Graduação em Bioinformática, Universidade Federal do Rio Grande do Norte, Natal 59078-400, RN, Brazil
| | - Vivaldo Gomes da Costa
- Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista (UNESP), São José do Rio Preto 15054-000, SP, Brazil;
| | - Gislaine Celestino Dutra da Silva
- Departamento de Doenças Dermatológicas, Infecciosas e Parasitárias, Faculdade de Medicina de São José do Rio Preto (FAMERP), São José do Rio Preto 15090-000, SP, Brazil; (M.V.S.); (G.C.D.d.S.)
| | - Rafael Elias Marques
- Laboratório Nacional de Biociências, Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Campinas 13083-100, SP, Brazil;
| | - Maurício Lacerda Nogueira
- Departamento de Doenças Dermatológicas, Infecciosas e Parasitárias, Faculdade de Medicina de São José do Rio Preto (FAMERP), São José do Rio Preto 15090-000, SP, Brazil; (M.V.S.); (G.C.D.d.S.)
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Sajid M, Marriam S, Mukhtar H, Sohail S, Sajid M, Sehgal SA. Epitope-based peptide vaccine design and elucidation of novel compounds against 3C like protein of SARS-CoV-2. PLoS One 2022; 17:e0264700. [PMID: 35324925 PMCID: PMC8947391 DOI: 10.1371/journal.pone.0264700] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 02/15/2022] [Indexed: 12/23/2022] Open
Abstract
Coronaviruses (CoVs) are positive-stranded RNA viruses with short clubs on their edges. CoVs are pathogenic viruses that infect several animals and plant organisms, as well as humans (lethal respiratory dysfunctions). A noval strain of CoV has been reported and named as SARS-CoV-2. Numerous COVID-19 cases were being reported all over the World. COVID-19 and has a high mortality rate. In the present study, immunoinformatics techniques were utilized to predict the antigenic epitopes against 3C like protein. B-cell epitopes and Cytotoxic T-lymphocyte (CTL) were designed computationally against SARS-CoV-2. Multiple Sequence Alignment (MSA) of seven complete strains (HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1, SARS-CoV, MERS-CoV, and SARS-CoV-2) was performed to elucidate the binding domain and interacting residues. MHC-I binding epitopes were evaluated by analyzing the binding affinity of the top-ranked peptides having HLA molecule. By utilizing the docked complexes of CTL epitopes with antigenic sites, the binding relationship and affinity of top-ranked predicted peptides with the MHC-I HLA protein were investigated. The molecular docking analyses were conducted on the ZINC database library and twelve compounds having least binding energy were scrutinized. In conclusion, twelve CTL epitopes (GTDLEGNFY, TVNVLAWLY, GSVGFNIDY, SEDMLNPNY, LSQTGIAV, VLDMCASLK, LTQDHVDIL, TTLNDFNLV, CTSEDMLNP, TTITVNVLA, YNGSPSGVY, and SMQNCVLKL) were identified against SARS-CoV-2.
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Affiliation(s)
- Muhammad Sajid
- Department of Biotechnology, University of Okara, Okara, Pakistan
| | - Saigha Marriam
- Department of Microbiology and Molecular Genetics, University of Okara, Okara, Pakistan
| | | | - Summar Sohail
- Department of Forestry, Kohsar University Murree, Murree, Pakistan
| | - Muhammad Sajid
- Department of Biotechnology, University of Okara, Okara, Pakistan
- * E-mail: (MS); (SAS)
| | - Sheikh Arslan Sehgal
- Department of Bioinformatics, University of Okara, Okara, Pakistan
- * E-mail: (MS); (SAS)
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Prediction of suitable T and B cell epitopes for eliciting immunogenic response against SARS-CoV-2 and its mutant. NETWORK MODELING AND ANALYSIS IN HEALTH INFORMATICS AND BIOINFORMATICS 2021; 11:1. [PMID: 34849327 PMCID: PMC8619655 DOI: 10.1007/s13721-021-00348-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 08/21/2021] [Accepted: 11/12/2021] [Indexed: 12/23/2022]
Abstract
Spike glycoprotein of SARS-CoV-2 is mainly responsible for the recognition and membrane fusion within the host and this protein has an ability to mutate. Hence, T cell and B cell epitopes were derived from the spike glycoprotein sequence of wild SARS-CoV-2. The proposed T cell and B cell epitopes were found to be antigenic and conserved in the sequence of SARS-CoV-2 mutant (B.1.1.7). Thus, the proposed epitopes are effective against SARS-CoV-2 and its B.1.1.7 mutant. MHC-I that best interacts with the proposed T cell epitopes were found, using immune epitope database. Molecular docking and molecular dynamic simulations were done for ensuring a good binding between the proposed MHC-I and T cell epitopes. The finally proposed T cell epitope was found to be antigenic, non-allergenic, non-toxic and stable. Further, the finally proposed B cell epitopes were also found to be antigenic. The population conservation analysis has ensured the presence of MHC-I molecule (respective to the finally proposed T cell) in human population of most affected countries with SARS-CoV-2. Thus the proposed T and B cell epitope could be effective in designing an epitope-based vaccine, which is effective on SARS-CoV-2 and its B.1.1.7mutant. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s13721-021-00348-w.
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A protective vaccine against the toxic activities following Brown spider accidents based on recombinant mutated phospholipases D as antigens. Int J Biol Macromol 2021; 192:757-770. [PMID: 34634338 DOI: 10.1016/j.ijbiomac.2021.10.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/30/2021] [Accepted: 10/01/2021] [Indexed: 11/24/2022]
Abstract
Accidents involving Brown spiders are reported throughout the world. In the venom, the major toxins involved in the deleterious effects are phospholipases D (PLDs). In this work, recombinant mutated phospholipases D from three endemic species medically relevant in South America (Loxosceles intermedia, L. laeta and L. gaucho) were tested as antigens in a vaccination protocol. In such isoforms, key amino acid residues involved in catalysis, magnesium-ion coordination, and binding to substrates were replaced by Alanine (H12A-H47A, E32A-D34A and W230A). These mutations eliminated the phospholipase activity and reduced the generation of skin necrosis and edema to residual levels. Molecular modeling of mutated isoforms indicated that the three-dimensional structures, topologies, and surface charges did not undergo significant changes. Mutated isoforms were recognized by sera against the crude venoms. Vaccination protocols in rabbits using mutated isoforms generated a serum that recognized the native PLDs of crude venoms and neutralized dermonecrosis and edema induced by L. intermedia venom. Vaccination of mice prevented the lethal effects of L. intermedia crude venom. Furthermore, vaccination of rabbits prevented the cutaneous lesion triggered by the three venoms. These results indicate a great potential for mutated recombinant PLDs to be employed as antigens in developing protective vaccines for Loxoscelism.
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Ezaj MMA, Haque MS, Syed SB, Khan MSA, Ahmed KR, Khatun MT, Nayeem SMA, Rizvi GR, Al-Forkan M, Khaleda L. Comparative proteomic analysis to annotate the structural and functional association of the hypothetical proteins of S. maltophilia k279a and predict potential T and B cell targets for vaccination. PLoS One 2021; 16:e0252295. [PMID: 34043709 PMCID: PMC8159010 DOI: 10.1371/journal.pone.0252295] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 05/07/2021] [Indexed: 11/18/2022] Open
Abstract
Stenotrophomonas maltophilia is a multidrug-resistant bacterium with no precise clinical treatment. This bacterium can be a vital cause for death and different organ failures in immune-compromised, immune-competent, and long-time hospitalized patients. Extensive quorum sensing capability has become a challenge to develop new drugs against this pathogen. Moreover, the organism possesses about 789 proteins which function, structure, and pathogenesis remain obscured. In this piece of work, we tried to enlighten the aforementioned sectors using highly reliable bioinformatics tools validated by the scientific community. At first, the whole proteome sequence of the organism was retrieved and stored. Then we separated the hypothetical proteins and searched for the conserved domain with a high confidence level and multi-server validation, which resulted in 24 such proteins. Furthermore, all of their physical and chemical characterizations were performed, such as theoretical isoelectric point, molecular weight, GRAVY value, and many more. Besides, the subcellular localization, protein-protein interactions, functional motifs, 3D structures, antigenicity, and virulence factors were also evaluated. As an extension of this work, 'RTFAMSSER' and 'PAAPQPSAS' were predicted as potential T and B cell epitopes, respectively. We hope our findings will help in better understating the pathogenesis and smoothen the way to the cure.
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Affiliation(s)
- Md. Muzahid Ahmed Ezaj
- Department of Genetic Engineering and Biotechnology, Faculty of Biological Sciences, University of Chittagong, Chattogram, Bangladesh
- Reverse Vaccinology Research Division, Advanced Bioinformatics, Computational Biology and Data Science Laboratory, Chittagong, Bangladesh
| | - Md. Sajedul Haque
- Department of Chemistry, Faculty of Science, University of Chittagong, Chattogram, Bangladesh
| | - Shifath Bin Syed
- Department of Biotechnology and Genetic Engineering, Faculty of Biological Sciences, Islamic University, Kushtia, Bangladesh
| | - Md. Shakil Ahmed Khan
- Department of Biotechnology and Genetic Engineering, Faculty of Biological Sciences, Islamic University, Kushtia, Bangladesh
| | - Kazi Rejvee Ahmed
- Department of Biotechnology and Genetic Engineering, Faculty of Biological Sciences, Islamic University, Kushtia, Bangladesh
| | - Mst. Tania Khatun
- Department of Biotechnology and Genetic Engineering, Faculty of Biological Sciences, Islamic University, Kushtia, Bangladesh
| | - S. M. Abdul Nayeem
- Reverse Vaccinology Research Division, Advanced Bioinformatics, Computational Biology and Data Science Laboratory, Chittagong, Bangladesh
- Department of Chemistry, Faculty of Science, University of Chittagong, Chattogram, Bangladesh
| | - Golam Rosul Rizvi
- Department of Genetic Engineering and Biotechnology, Faculty of Biological Sciences, University of Chittagong, Chattogram, Bangladesh
| | - Mohammad Al-Forkan
- Department of Genetic Engineering and Biotechnology, Faculty of Biological Sciences, University of Chittagong, Chattogram, Bangladesh
| | - Laila Khaleda
- Department of Genetic Engineering and Biotechnology, Faculty of Biological Sciences, University of Chittagong, Chattogram, Bangladesh
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Waqas M, Haider A, Rehman A, Qasim M, Umar A, Sufyan M, Akram HN, Mir A, Razzaq R, Rasool D, Tahir RA, Sehgal SA. Immunoinformatics and Molecular Docking Studies Predicted Potential Multiepitope-Based Peptide Vaccine and Novel Compounds against Novel SARS-CoV-2 through Virtual Screening. BIOMED RESEARCH INTERNATIONAL 2021; 2021:1596834. [PMID: 33728324 PMCID: PMC7910514 DOI: 10.1155/2021/1596834] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 08/13/2020] [Accepted: 02/08/2021] [Indexed: 02/06/2023]
Abstract
BACKGROUND Coronaviruses (CoVs) are enveloped positive-strand RNA viruses which have club-like spikes at the surface with a unique replication process. Coronaviruses are categorized as major pathogenic viruses causing a variety of diseases in birds and mammals including humans (lethal respiratory dysfunctions). Nowadays, a new strain of coronaviruses is identified and named as SARS-CoV-2. Multiple cases of SARS-CoV-2 attacks are being reported all over the world. SARS-CoV-2 showed high death rate; however, no specific treatment is available against SARS-CoV-2. METHODS In the current study, immunoinformatics approaches were employed to predict the antigenic epitopes against SARS-CoV-2 for the development of the coronavirus vaccine. Cytotoxic T-lymphocyte and B-cell epitopes were predicted for SARS-CoV-2 coronavirus protein. Multiple sequence alignment of three genomes (SARS-CoV, MERS-CoV, and SARS-CoV-2) was used to conserved binding domain analysis. RESULTS The docking complexes of 4 CTL epitopes with antigenic sites were analyzed followed by binding affinity and binding interaction analyses of top-ranked predicted peptides with MHC-I HLA molecule. The molecular docking (Food and Drug Regulatory Authority library) was performed, and four compounds exhibiting least binding energy were identified. The designed epitopes lead to the molecular docking against MHC-I, and interactional analyses of the selected docked complexes were investigated. In conclusion, four CTL epitopes (GTDLEGNFY, TVNVLAWLY, GSVGFNIDY, and QTFSVLACY) and four FDA-scrutinized compounds exhibited potential targets as peptide vaccines and potential biomolecules against deadly SARS-CoV-2, respectively. A multiepitope vaccine was also designed from different epitopes of coronavirus proteins joined by linkers and led by an adjuvant. CONCLUSION Our investigations predicted epitopes and the reported molecules that may have the potential to inhibit the SARS-CoV-2 virus. These findings can be a step towards the development of a peptide-based vaccine or natural compound drug target against SARS-CoV-2.
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Affiliation(s)
- Muhammad Waqas
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
| | - Ali Haider
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
| | - Abdur Rehman
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
| | - Muhammad Qasim
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
| | - Ahitsham Umar
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
| | - Muhammad Sufyan
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
| | - Hafiza Nisha Akram
- Department of Environmental Sciences, Quaid-e-Azam University, Islamabad, Pakistan
| | - Asif Mir
- Department of Biological Sciences, International Islamic University, Islamabad, Pakistan
| | - Roha Razzaq
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
| | - Danish Rasool
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
| | - Rana Adnan Tahir
- Department of Biosciences, COMSATS University, Sahiwal Campus, Islamabad, Pakistan
| | - Sheikh Arslan Sehgal
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
- Department of Bioinformatics, University of Okara, Okara, Pakistan
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Munia M, Mahmud S, Mohasin M, Kibria KK. In silico design of an epitope-based vaccine against choline binding protein A of Streptococcus pneumoniae. INFORMATICS IN MEDICINE UNLOCKED 2021. [DOI: 10.1016/j.imu.2021.100546] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
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Waqas M, Haider A, Sufyan M, Siraj S, Sehgal SA. Determine the Potential Epitope Based Peptide Vaccine Against Novel SARS-CoV-2 Targeting Structural Proteins Using Immunoinformatics Approaches. Front Mol Biosci 2020; 7:227. [PMID: 33195402 PMCID: PMC7593713 DOI: 10.3389/fmolb.2020.00227] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 08/11/2020] [Indexed: 12/23/2022] Open
Abstract
Coronaviruses (CoVs) belong to the Coronaviridae-family. The genus Beta-coronaviruses, are enveloped positive strand RNA viruses with club-like spikes at the surface with a unique replication process and a large RNA genome (∼25 kb). CoVs are known as one of the major pathogenic viruses causing a variety of diseases in birds and mammals including humans (lethal respiratory dysfunctions). Recently, a new strain of coronavirus has been identified and named as SARS-CoV-2. A large number of COVID-19 (disease caused by SARS-CoV-2) cases are being diagnosed all over the World especially in China (Wuhan). COVID-19 showed high mortality rate exponentially, however, not even a single effective cure is being introduced yet against COVID-19. In the current study, immunoinformatics approaches were employed to predict the antigenic epitopes against COVID-19 for the development of a coronavirus peptide vaccine. Cytotoxic T-lymphocyte (CTL) and B-cell epitopes were predicted for SARS-CoV-2 coronavirus structural proteins (Spikes, Membrane, Envelope, and Nucleocapsid). The docking complexes of the top 10 epitopes having antigenic sites were analyzed led by binding affinity and binding interactional analyses of top ranked predicted peptides with the MHC-I HLA molecule. The predicted peptides may have potential to be used as peptide vaccine against COVID-19.
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Affiliation(s)
- Muhammad Waqas
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Ali Haider
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Muhammad Sufyan
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
| | - Sami Siraj
- Institute of Basic Medical Sciences, Khyber Medical University, Peshawar, Pakistan
| | - Sheikh Arslan Sehgal
- Department of Bioinformatics and Biotechnology, Government College University Faisalabad, Faisalabad, Pakistan
- Department of Bioinformatics, University of Okara, Okara, Pakistan
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Rehman HM, Mirza MU, Ahmad MA, Saleem M, Froeyen M, Ahmad S, Gul R, Alghamdi HA, Aslam MS, Sajjad M, Bhinder MA. A Putative Prophylactic Solution for COVID-19: Development of Novel Multiepitope Vaccine Candidate against SARS-COV-2 by Comprehensive Immunoinformatic and Molecular Modelling Approach. BIOLOGY 2020; 9:E296. [PMID: 32962156 PMCID: PMC7563440 DOI: 10.3390/biology9090296] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 09/04/2020] [Accepted: 09/05/2020] [Indexed: 12/13/2022]
Abstract
The outbreak of 2019-novel coronavirus (SARS-CoV-2) that causes severe respiratory infection (COVID-19) has spread in China, and the World Health Organization has declared it a pandemic. However, no approved drug or vaccines are available, and treatment is mainly supportive and through a few repurposed drugs. The urgency of the situation requires the development of SARS-CoV-2-based vaccines. Immunoinformatic and molecular modelling are time-efficient methods that are generally used to accelerate the discovery and design of the candidate peptides for vaccine development. In recent years, the use of multiepitope vaccines has proved to be a promising immunization strategy against viruses and pathogens, thus inducing more comprehensive protective immunity. The current study demonstrated a comprehensive in silico strategy to design stable multiepitope vaccine construct (MVC) from B-cell and T-cell epitopes of essential SARS-CoV-2 proteins with the help of adjuvants and linkers. The integrated molecular dynamics simulations analysis revealed the stability of MVC and its interaction with human Toll-like receptors (TLRs), which trigger an innate and adaptive immune response. Later, the in silico cloning in a known pET28a vector system also estimated the possibility of MVC expression in Escherichia coli. Despite that this study lacks validation of this vaccine construct in terms of its efficacy, the current integrated strategy encompasses the initial multiple epitope vaccine design concepts. After validation, this MVC can be present as a better prophylactic solution against COVID-19.
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Affiliation(s)
- Hafiz Muzzammel Rehman
- Institute of Biochemistry and Biotechnology, University of the Punjab, Lahore 54590, Punjab, Pakistan; (H.M.R.); (M.S.A.)
- Department of Human Genetics and Molecular Biology, University of Health Sciences, Lahore 54590, Punjab, Pakistan; (M.A.A.); (M.A.B.)
| | - Muhammad Usman Mirza
- Department of Pharmaceutical and Pharmacological Sciences, Rega Institute for Medical Research, Medicinal Chemistry, University of Leuven, B-3000 Leuven, Belgium; (M.U.M.); (M.F.)
| | - Mian Azhar Ahmad
- Department of Human Genetics and Molecular Biology, University of Health Sciences, Lahore 54590, Punjab, Pakistan; (M.A.A.); (M.A.B.)
- Department of Health, Government of the Punjab, Lahore 54590, Punjab, Pakistan
| | - Mahjabeen Saleem
- Institute of Biochemistry and Biotechnology, University of the Punjab, Lahore 54590, Punjab, Pakistan; (H.M.R.); (M.S.A.)
| | - Matheus Froeyen
- Department of Pharmaceutical and Pharmacological Sciences, Rega Institute for Medical Research, Medicinal Chemistry, University of Leuven, B-3000 Leuven, Belgium; (M.U.M.); (M.F.)
| | - Sarfraz Ahmad
- Drug Design and Development Research Group (DDDRG), Department of Chemistry, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia;
| | - Roquyya Gul
- Faculty of Life Sciences, Gulab Devi Educational Complex, Lahore 54590, Punjab, Pakistan;
| | - Huda Ahmed Alghamdi
- Department of Biology, College of Sciences, King Khalid University, Abha 61413, Saudi Arabia;
| | - Muhammad Shahbaz Aslam
- Institute of Biochemistry and Biotechnology, University of the Punjab, Lahore 54590, Punjab, Pakistan; (H.M.R.); (M.S.A.)
| | - Muhammad Sajjad
- School of Biological Sciences, University of the Punjab, Quaid e Azam Campus, Lahore 54590, Punjab, Pakistan;
| | - Munir Ahmad Bhinder
- Department of Human Genetics and Molecular Biology, University of Health Sciences, Lahore 54590, Punjab, Pakistan; (M.A.A.); (M.A.B.)
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13
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Khalid H, Ashfaq UA. Exploring HCV genome to construct multi-epitope based subunit vaccine to battle HCV infection: Immunoinformatics based approach. J Biomed Inform 2020; 108:103498. [PMID: 32621883 DOI: 10.1016/j.jbi.2020.103498] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 05/03/2020] [Accepted: 06/25/2020] [Indexed: 01/16/2023]
Abstract
Hepatitis C Virus (HCV) infection is a major cause of chronic liver disease, hepatocellular carcinoma, and the single most common indication for liver transplantation. HCV vaccines eliciting specific T-cell responses, have been considered as potent method to prevent HCV infection. Despite several reports on progress of vaccine, these vaccine failed in mediating clinical relevance activity against HCV in humans. In this study we integrated both immunoinformatic and molecular docking approach to present a multiepitope vaccine against HCV by designating 17 conserved epitopes from eight viral proteins such as Core protein, E1, E2, NS2, NS34A, NS4B, NS5A, and NS5B. The epitopes were prioritized based on conservation among epitopes of T cell, B cell and IFN-γ that were then scanned for non-homologous to host and antigenicity. The prioritized epitopes were then linked together by AAY linker and adjuvant (β-defensin) were attached at N-terminal to enhance immunogenic potential. The construct thus formed were subjected to structural modeling and physiochemical characteristics. The modeled structure were successfully docked to antigenic receptor TLR-3 and In-silico cloning confers the authenticity of its expression efficiency. However, the proposed construct need to be validate experimentally to ensure its safety and immunogenic profile.
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Affiliation(s)
- Hina Khalid
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan
| | - Usman Ali Ashfaq
- Department of Bioinformatics and Biotechnology, Government College University, Faisalabad, Pakistan.
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14
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Bappy SS, Sultana S, Adhikari J, Mahmud S, Khan MA, Kibria KMK, Rahman MM, Shibly AZ. Extensive immunoinformatics study for the prediction of novel peptide-based epitope vaccine with docking confirmation against envelope protein of Chikungunya virus: a computational biology approach. J Biomol Struct Dyn 2020; 39:1139-1154. [PMID: 32037968 DOI: 10.1080/07391102.2020.1726815] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chikungunya virus (CHIKV) instigating Chikungunya fever is a global infective menace resulting in high fever, weakened joint-muscle pain, and brain inflammation. Inaccessibility and unavailability of effective drugs have led us to an uncertain arena when it comes to providing proper medical treatment to the affected people. In this study, authentic encroachment has been made concerning the peptide-based epitope vaccine designing against CHIKV. A Proteome-wide search was performed to locate a conserved portion among the accessible viral outer membrane proteins which showcase a remarkable immune response using specific immunoinformatics and docking simulation tools. Primarily, the most probable immunogenic envelope glycoproteins E1 and E2 were identified from the UniProt database depending on their antigenicity scores. Subsequently, we selected two distinctive sequences "SEDVYANTQLVLQRP" and "IMLLYPDHPTLLSYR" in both E1 and E2 glycoproteins respectively. These two sequences identified as the most potent T and B cell epitope-based peptides as they interacted with 6 and 7 HLA-I and 5 HLA-II molecules with an extremely low IC50 score that was verified by molecular docking. Moreover, the sequences possess no allergenicity and are certainly located outside the transmembrane region. In addition, the sequences exhibited 88.46% and 100.00% Conservancy, covering high population coverage of 89.49% to 94.74% and 60.51% to 88.87% respectively in endemic countries. The identified peptide SEDVYANTQLVLQRP and IMLLYPDHPTLLSYR can be utilized next for the development of peptide-based epitope vaccine contrary to CHIKV, so further documentations and experimentations like Antigen testing, Antigen production, Clinical trials are needed to prove the validity of it. Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Syed Shahariar Bappy
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Tangail, Bangladesh
| | - Sorna Sultana
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Tangail, Bangladesh
| | - Juthi Adhikari
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Tangail, Bangladesh
| | - Shafi Mahmud
- Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, Bangladesh
| | - Md Arif Khan
- Department of Biotechnology and Genetic Engineering, University of Development Alternative, Dhaka, Bangladesh.,Bio-Bio-1 Research Foundation, Sangskriti Bikash Kendra Bhaban, Dhaka, Bangladesh
| | - K M Kaderi Kibria
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Tangail, Bangladesh
| | - Md Masuder Rahman
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Tangail, Bangladesh
| | - Abu Zaffar Shibly
- Department of Biotechnology and Genetic Engineering, Mawlana Bhashani Science and Technology University, Tangail, Bangladesh
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15
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Lata KS, Vaghasia V, Bhairappanvar S, Patel S, Das J. Vaccine Design Against Leptospirosis Using an Immunoinformatic Approach. Methods Mol Biol 2020; 2131:173-184. [PMID: 32162253 DOI: 10.1007/978-1-0716-0389-5_7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Vaccination is the best way to prevent the spread of emerging or reemerging infectious disease. Current research for vaccine development is mainly focused on recombinant-, subunit-, and peptide-based vaccine. At this point, immunoinformatics has been proven as a powerful method for identification of potential vaccine candidates, by analyzing immunodominat B- and T-cell epitopes. This method can reduce the time and cost of experiment to a great extent, by reducing the number of vaccine candidates for experimental testing for their efficacy. This chapter describes the use of immunoinformatics and molecular docking methods to screen potential vaccine candidates by taking Leptospira as a model.
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Affiliation(s)
- Kumari Snehkant Lata
- Gujarat Biotechnology Research Centre, Department of Science and Technology, Government of Gujarat, Gandhinagar, India
- Department of Botany, Bioinformatics and Climate Change, Gujarat University, Ahmedabad, India
| | - Vibhisha Vaghasia
- Gujarat Biotechnology Research Centre, Department of Science and Technology, Government of Gujarat, Gandhinagar, India
- Department of Botany, Bioinformatics and Climate Change, Gujarat University, Ahmedabad, India
| | - Shivarudrappa Bhairappanvar
- Gujarat Biotechnology Research Centre, Department of Science and Technology, Government of Gujarat, Gandhinagar, India
| | - Saumya Patel
- Department of Botany, Bioinformatics and Climate Change, Gujarat University, Ahmedabad, India
| | - Jayashankar Das
- Gujarat Biotechnology Research Centre, Department of Science and Technology, Government of Gujarat, Gandhinagar, India.
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16
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Mehmood A, Kaushik AC, Wei DQ. Prediction and validation of potent peptides against herpes simplex virus type 1 via immunoinformatic and systems biology approach. Chem Biol Drug Des 2019; 94:1868-1883. [PMID: 31437863 DOI: 10.1111/cbdd.13602] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 07/23/2019] [Accepted: 08/10/2019] [Indexed: 12/19/2022]
Abstract
The human herpes simplex virus type 1 (HSV-1) is an extremely rampant human pathogen, and its infection could cause life-long diseases, including the central nervous system disorders. The glycoproteins of HSV-1 such as glycoprotein B, glycoprotein C, glycoprotein D, glycoprotein H, and glycoprotein L are highly involved in mediating the viral attachment and infection of the host cell. Therefore, immunoinformatic approaches followed by molecular dynamics simulation and systems biology has been used to analyze these glycoproteins in order to propose effective peptide-based vaccine candidates against the HSV-1 infection. The ElliPro and NetCTL.1.2 online tools were employed to forecast the B- and T-lymphocyte (CTL) epitopes for gB, gC, gD, gH, and gL. The 3D coordinates of these epitopes were modeled and docked against the human major histocompatibility complex molecule-1. The outcomes obtained from postdocking analysis along with TAP (Transporter associated with antigen processing), MHC binding, and C-terminal cleavage score assisted in the selection of potential epitopes. These epitopes were further subjected to molecular dynamics simulation and systems biology approach which showed significant results. On the basis of these substantial outcomes, peptides are proposed that could be used to provoke immunity against the HSV-1 infection.
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Affiliation(s)
- Aamir Mehmood
- State Key Laboratory of Microbial Metabolism, College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Aman Chandra Kaushik
- State Key Laboratory of Microbial Metabolism, College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Dong-Qing Wei
- State Key Laboratory of Microbial Metabolism, College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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17
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Localization Analysis of Heterophilic Antigen Epitopes of H1N1 Influenza Virus Hemagglutinin. Virol Sin 2019; 34:306-314. [PMID: 31020574 DOI: 10.1007/s12250-019-00100-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 01/23/2019] [Indexed: 10/26/2022] Open
Abstract
Previous studies have indicated that two monoclonal antibodies (mAbs; A1-10 and H1-84) of the hemagglutinin (HA) antigen on the H1N1 influenza virus cross-react with human brain tissue. It has been proposed that there are heterophilic epitopes between the HA protein and human brain tissue (Guo et al. in Immunobiology 220:941-946, 2015). However, characterisation of the two mAbs recognising the heterophilic epitope on HA has not yet been performed. In the present study, the common antigens of influenza virus HA were confirmed using indirect enzyme-linked immunosorbent assays and analysed with DNAMAN software. The epitopes were localized to nine peptides in the influenza virus HA sequence and the distribution of the peptides in the three-dimensional structure of HA was determined using PyMOL software. Key amino acids and variable sequences of the antibodies were identified using abYsis software. The results demonstrated that there were a number of common antigens among the five influenza viruses studied that were recognised by the mAbs. One of the peptides, P2 (LVLWGIHHP191-199), bound both of the mAbs and was located in the head region of HA. The key amino acids of this epitope and the variable regions in the heavy and light chain sequences of the mAbs that recognised the epitope are described. A heterophilic epitope on H1N1 influenza virus HA was also introduced. The existence of this epitope provides a novel perspective for the occurrence of nervous system diseases that could be caused by influenza virus infection, which might aid in influenza prevention and control.
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18
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Ali A, Khan A, Kaushik AC, Wang Y, Ali SS, Junaid M, Saleem S, Cho WCS, Mao X, Wei DQ. Immunoinformatic and systems biology approaches to predict and validate peptide vaccines against Epstein-Barr virus (EBV). Sci Rep 2019; 9:720. [PMID: 30679646 PMCID: PMC6346095 DOI: 10.1038/s41598-018-37070-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 11/30/2018] [Indexed: 12/19/2022] Open
Abstract
Epstein-Barr virus (EBV), also known as human herpesvirus 4 (HHV-4), is a member of the Herpesviridae family and causes infectious mononucleosis, Burkitt's lymphoma, and nasopharyngeal carcinoma. Even in the United States of America, the situation is alarming, as EBV affects 95% of the young population between 35 and 40 years of age. In this study, both linear and conformational B-cell epitopes as well as cytotoxic T-lymphocyte (CTL) epitopes were predicted by using the ElliPro and NetCTL.1.2 webservers for EBV proteins (GH, GL, GB, GN, GM, GP42 and GP350). Molecular modelling tools were used to predict the 3D coordinates of peptides, and these peptides were then docked against the MHC molecules to obtain peptide-MHC complexes. Studies of their post-docking interactions helped to select potential candidates for the development of peptide vaccines. Our results predicted a total of 58 T-cell epitopes of EBV; where the most potential were selected based on their TAP, MHC binding and C-terminal Cleavage score. The top most peptides were subjected to MD simulation and stability analysis. Validation of our predicted epitopes using a 0.45 µM concentration was carried out by using a systems biology approach. Our results suggest a panel of epitopes that could be used to immunize populations to protect against multiple diseases caused by EBV.
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Affiliation(s)
- Arif Ali
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
| | - Abbas Khan
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Aman Chandra Kaushik
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Yanjie Wang
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Syed Shujait Ali
- Center for Biotechnology and Microbiology, University of Swat, Khyber Pakhtunkhwa, Pakistan
| | - Muhammad Junaid
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Shoaib Saleem
- Center for Biotechnology and Microbiology, University of Swat, Khyber Pakhtunkhwa, Pakistan
| | - William C S Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, Kowloon, Hong Kong
| | - Xueying Mao
- Qianweichang College, Shanghai University, Shanghai, China
| | - Dong-Qing Wei
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
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19
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Ge C, Xu B, Liang B, Lönnblom E, Lundström SL, Zubarev RA, Ayoglu B, Nilsson P, Skogh T, Kastbom A, Malmström V, Klareskog L, Toes REM, Rispens T, Dobritzsch D, Holmdahl R. Structural Basis of Cross-Reactivity of Anti-Citrullinated Protein Antibodies. Arthritis Rheumatol 2019; 71:210-221. [PMID: 30152126 DOI: 10.1002/art.40698] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 08/23/2018] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Anti-citrullinated protein antibodies (ACPAs) develop many years before the clinical onset of rheumatoid arthritis (RA). This study was undertaken to address the molecular basis of the specificity and cross-reactivity of ACPAs from patients with RA. METHODS Antibodies isolated from RA patients were expressed as monoclonal chimeric antibodies with mouse Fc. These antibodies were characterized for glycosylation using mass spectrometry, and their cross-reactivity was assessed using Biacore and Luminex immunoassays. The crystal structures of the antigen-binding fragment (Fab) of the monoclonal ACPA E4 in complex with 3 different citrullinated peptides were determined using x-ray crystallography. The prevalence of autoantibodies reactive against 3 of the citrullinated peptides that also interacted with E4 was investigated by Luminex immunoassay in 2 Swedish cohorts of RA patients. RESULTS Analysis of the crystal structures of a monoclonal ACPA from human RA serum in complex with citrullinated peptides revealed key residues of several complementarity-determining regions that recognized the citrulline as well as the neighboring peptide backbone, but with limited contact with the side chains of the peptides. The same citrullinated peptides were recognized by high titers of serum autoantibodies in 2 large cohorts of RA patients. CONCLUSION These data show, for the first time, how ACPAs derived from human RA serum recognize citrulline. The specific citrulline recognition and backbone-mediated interactions provide a structural explanation for the promiscuous recognition of citrullinated peptides by RA-specific ACPAs.
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Affiliation(s)
| | - Bingze Xu
- Karolinska Institutet, Stockholm, Sweden
| | - Bibo Liang
- Karolinska Institutet, Stockholm, Sweden, and Southern Medical University, Guangzhou, China
| | | | | | | | - Burcu Ayoglu
- KTH Royal Institute of Technology, Stockholm, Sweden
| | - Peter Nilsson
- KTH Royal Institute of Technology, Stockholm, Sweden
| | | | | | - Vivianne Malmström
- Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
| | - Lars Klareskog
- Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
| | - René E M Toes
- Leiden University Medical Center, Leiden, The Netherlands
| | - Theo Rispens
- University of Amsterdam, Amsterdam, The Netherlands
| | | | - Rikard Holmdahl
- Karolinska Institutet, Stockholm, Sweden, and Southern Medical University, Guangzhou, China
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20
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Tahir RA, Wu H, Rizwan MA, Jafar TH, Saleem S, Sehgal SA. Immunoinformatics and molecular docking studies reveal potential epitope-based peptide vaccine against DENV-NS3 protein. J Theor Biol 2018; 459:162-170. [PMID: 30291844 DOI: 10.1016/j.jtbi.2018.10.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 09/27/2018] [Accepted: 10/01/2018] [Indexed: 11/25/2022]
Abstract
Dengue, still a "Neglected Tropical Disease" is somehow injustice and remains uncontrolled globally. World Health Organization (2012-2020) reported that the world's half population is living in dengue-affected regions. Therefore, effective drug candidates or promising vaccines are urgently needed to control the dengue. It is an acute febrile disease caused by mosquito borne dengue viruses (DENVs) which belong to the genus Flavivirus with four serotypes. In present work, immunoinformatics approach was utilized to predict the antigenic epitopes of dengue proteins for the development of DENV vaccine. B-cell and cytotoxic T-lymphocyte epitopes were predicted for NS3 dengue protein. Docking complexes of 17 antigenic B-cell epitopes of various lengths and 4 CTL epitopes with antigenic sites were investigated followed by binding interaction analyses of top predicted peptides with MHC-I HLA-A2 molecule. These predicted epitopes with antigenic amino acids might present a preliminary set of peptides for future vaccine development against DENV.
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Affiliation(s)
- Rana Adnan Tahir
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Pakistan; Beijing Key Laboratory of Separation and Analysis in Biomedical and Pharmaceuticals, Department of Biomedical Engineering, School of Life Sciences, Beijing Institute of Technology, China
| | - Hao Wu
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | | | | | - Shahzad Saleem
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Pakistan
| | - Sheikh Arslan Sehgal
- Department of Biosciences, COMSATS University Islamabad, Sahiwal Campus, Pakistan; State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China.
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21
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Miyanabe K, Akiba H, Kuroda D, Nakakido M, Kusano-Arai O, Iwanari H, Hamakubo T, Caaveiro JMM, Tsumoto K. Intramolecular H-bonds govern the recognition of a flexible peptide by an antibody. J Biochem 2018; 164:65-76. [PMID: 29924367 DOI: 10.1093/jb/mvy032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 02/06/2018] [Indexed: 02/06/2023] Open
Abstract
Molecular recognition is a fundamental event at the core of essentially every biological process. In particular, intermolecular H-bonds have been recognized as key stabilizing forces in antibody-antigen interactions resulting in exquisite specificity and high affinity. Although equally abundant, the role of intramolecular H-bonds is far less clear and not universally acknowledged. Herein, we have carried out a molecular-level study to dissect the contribution of intramolecular H-bonds in a flexible peptide for the recognition by an antibody. We show that intramolecular H-bonds may have a profound, multifaceted and favorable effect on the binding affinity by up to 2 kcal mol-1 of free energy. Collectively, our results suggest that antibodies are fine tuned to recognize transiently stabilized structures of flexible peptides in solution, for which intramolecular H-bonds play a key role.
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Affiliation(s)
- Kazuhiro Miyanabe
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hiroki Akiba
- Department of Bioengineering, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.,Laboratory of Pharmacokinetic Optimization, Center for Drug Design Research, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki City, Osaka 567-0085, Japan
| | - Daisuke Kuroda
- Department of Bioengineering, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Makoto Nakakido
- Department of Bioengineering, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Osamu Kusano-Arai
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo 153-8904, Japan
| | - Hiroko Iwanari
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo 153-8904, Japan
| | - Takao Hamakubo
- Quantitative Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Meguro-ku, Tokyo 153-8904, Japan
| | - Jose M M Caaveiro
- Department of Bioengineering, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.,Laboratory of Global Healthcare, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Kouhei Tsumoto
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.,Department of Bioengineering, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.,Laboratory of Pharmacokinetic Optimization, Center for Drug Design Research, National Institutes of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki City, Osaka 567-0085, Japan.,Laboratory of Medical Proteomics, Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan
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22
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Hossain MU, Keya CA, Das KC, Hashem A, Omar TM, Khan MA, Rakib-Uz-Zaman SM, Salimullah M. An Immunopharmacoinformatics Approach in Development of Vaccine and Drug Candidates for West Nile Virus. Front Chem 2018; 6:246. [PMID: 30035107 PMCID: PMC6043868 DOI: 10.3389/fchem.2018.00246] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 06/08/2018] [Indexed: 01/02/2023] Open
Abstract
An outbreak of West Nile Virus (WNV) like the recent Ebola can be more epidemic and fatal to public health throughout the world. WNV possesses utmost threat as no vaccine or drug is currently available for its treatment except mosquito control. The current study applied the combined approach of immunoinformatics and pharmacoinformatics to design potential epitope-based vaccines and drug candidates against WNV. By analyzing the whole proteome of 2994 proteins, the WNV envelope glycoprotein was selected as a therapeutic target based on its highest antigenicity. After proper assessment “KSFLVHREW” and “ITPSAPSYT” were found to be the most potential T and B-cell epitopes, respectively. Besides, we have designed and validated four novel drugs from a known WNV inhibitor, AP30451 by adopting computational approaches. Toxicity assessment and drug score confirmed the effectiveness of these drug candidates. This in silico research might greatly facilitate the wet lab experiments to develop vaccine and drug against WNV.
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Affiliation(s)
| | - Chaman Ara Keya
- Department of Biochemistry and Microbiology, North South University, Dhaka, Bangladesh
| | - Keshob Chandra Das
- Molecular Biotechnology Division, National Institute of Biotechnology, Dhaka, Bangladesh
| | - Abu Hashem
- Microbial Biotechnology Division, National Institute of Biotechnology, Dhaka, Bangladesh
| | - Taimur Md Omar
- Department of Biotechnology and Genetic Engineering, Life Science Faculty, Mawlana Bhashani Science and Technology University, Tangail, Bangladesh
| | - Md Arif Khan
- Bio-Bio-1 Research Foundation, Sangskriti Bikash Kendra Bhavan, Dhaka, Bangladesh
| | - S M Rakib-Uz-Zaman
- Department of Mathematics and Natural Sciences, Biotechnology Program, BRAC University, Dhaka, Bangladesh
| | - Md Salimullah
- Molecular Biotechnology Division, National Institute of Biotechnology, Dhaka, Bangladesh
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23
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Lata KS, Kumar S, Vaghasia V, Sharma P, Bhairappanvar SB, Soni S, Das J. Exploring Leptospiral proteomes to identify potential candidates for vaccine design against Leptospirosis using an immunoinformatics approach. Sci Rep 2018; 8:6935. [PMID: 29720698 PMCID: PMC5932004 DOI: 10.1038/s41598-018-25281-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 04/18/2018] [Indexed: 01/12/2023] Open
Abstract
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 immunogenic outer membrane lipoprotein. Further, the binding interaction of CTL epitopes with Major Histocompatibility Complex class I (MHC-I) was evaluated using docking techniques. A Molecular Dynamics Simulation study was also performed to evaluate the stability of the resulting epitope-MHC-I complexes. Overall, this study provides novel vaccine candidates and may prompt further development of vaccines against leptospirosis.
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Affiliation(s)
- Kumari Snehkant Lata
- Gujarat Institute of Bioinformatics, Gujarat State Biotechnology Mission, Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India.,Gujarat Biotechnology Research Centre (GBRC), Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India
| | - Swapnil Kumar
- Gujarat Institute of Bioinformatics, Gujarat State Biotechnology Mission, Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India.,Gujarat Biotechnology Research Centre (GBRC), Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India
| | - Vibhisha Vaghasia
- Gujarat Institute of Bioinformatics, Gujarat State Biotechnology Mission, Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India.,Gujarat Biotechnology Research Centre (GBRC), Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India
| | - Priyanka Sharma
- Gujarat Institute of Bioinformatics, Gujarat State Biotechnology Mission, Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India.,Gujarat Biotechnology Research Centre (GBRC), Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India
| | - Shivarudrappa B Bhairappanvar
- Gujarat Institute of Bioinformatics, Gujarat State Biotechnology Mission, Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India.,Gujarat Biotechnology Research Centre (GBRC), Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India
| | - Subhash Soni
- Gujarat State Biotechnology Mission, Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India.,Gujarat Biotechnology Research Centre (GBRC), Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India
| | - Jayashankar Das
- Gujarat State Biotechnology Mission, Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India. .,Gujarat Biotechnology Research Centre (GBRC), Department of Science & Technology, Government of Gujarat, Gandhinagar, 382011, India.
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Khan A, Junaid M, Kaushik AC, Ali A, Ali SS, Mehmood A, Wei DQ. Computational identification, characterization and validation of potential antigenic peptide vaccines from hrHPVs E6 proteins using immunoinformatics and computational systems biology approaches. PLoS One 2018; 13:e0196484. [PMID: 29715318 PMCID: PMC5929558 DOI: 10.1371/journal.pone.0196484] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 04/13/2018] [Indexed: 01/01/2023] Open
Abstract
High-risk human papillomaviruses (hrHPVs) are the most prevalent viruses in human diseases including cervical cancers. Expression of E6 protein has already been reported in cervical cancer cases, excluding normal tissues. Continuous expression of E6 protein is making it ideal to develop therapeutic vaccines against hrHPVs infection and cervical cancer. Therefore, we carried out a meta-analysis of multiple hrHPVs to predict the most potential prophylactic peptide vaccines. In this study, immunoinformatics approach was employed to predict antigenic epitopes of hrHPVs E6 proteins restricted to 12 Human HLAs to aid the development of peptide vaccines against hrHPVs. Conformational B-cell and CTL epitopes were predicted for hrHPVs E6 proteins using ElliPro and NetCTL. The potential of the predicted peptides were tested and validated by using systems biology approach considering experimental concentration. We also investigated the binding interactions of the antigenic CTL epitopes by using docking. The stability of the resulting peptide-MHC I complexes was further studied by molecular dynamics simulations. The simulation results highlighted the regions from 46–62 and 65–76 that could be the first choice for the development of prophylactic peptide vaccines against hrHPVs. To overcome the worldwide distribution, the predicted epitopes restricted to different HLAs could cover most of the vaccination and would help to explore the possibility of these epitopes for adaptive immunotherapy against HPVs infections.
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Affiliation(s)
- Abbas Khan
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Muhammad Junaid
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Aman Chandra Kaushik
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Arif Ali
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Syed Shujait Ali
- Center for Biotechnology and Microbiology, University of Swat, Khyber Pakhtunkhwa, Pakistan
| | - Aamir Mehmood
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Dong-Qing Wei
- State Key Laboratory of Microbial Metabolism, and College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
- * E-mail:
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25
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Hossain MU, Omar TM, Oany AR, Kibria KMK, Shibly AZ, Moniruzzaman M, Ali SR, Islam MM. Design of peptide-based epitope vaccine and further binding site scrutiny led to groundswell in drug discovery against Lassa virus. 3 Biotech 2018; 8:81. [PMID: 29430345 DOI: 10.1007/s13205-018-1106-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 01/07/2018] [Indexed: 10/18/2022] Open
Abstract
Lassa virus (LASV) is responsible for an acute viral hemorrhagic fever known as Lassa fever. Sequence analyses of LASV proteome identified the most immunogenic protein that led to predict both T-cell and B-cell epitopes and further target and binding site depiction could allow novel drug findings for drug discovery field against this virus. To induce both humoral and cell-mediated immunity peptide sequence SSNLYKGVY, conserved region 41-49 amino acids were found as the most potential B-cell and T-cell epitopes, respectively. The peptide sequence might intermingle with 17 HLA-I and 16 HLA-II molecules, also cover 49.15-96.82% population coverage within the common people of different countries where Lassa virus is endemic. To ensure the binding affinity to both HLA-I and HLA-II molecules were employed in docking simulation with suggested epitope sequence. Further the predicted 3D structure of the most immunogenic protein was analyzed to reveal out the binding site for the drug design against Lassa Virus. Herein, sequence analyses of proteome identified the most immunogenic protein that led to predict both T-cell and B-cell epitopes and further target and binding site depiction could allow novel drug findings for drug discovery field against this virus.
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Epitope Specificity of Anti-Citrullinated Protein Antibodies. Antibodies (Basel) 2017; 6:antib6010005. [PMID: 31548521 PMCID: PMC6698845 DOI: 10.3390/antib6010005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/06/2017] [Accepted: 02/22/2017] [Indexed: 01/21/2023] Open
Abstract
Anti-citrullinated protein antibodies are primarily associated with a progressive course in the autoimmune disease rheumatoid arthritis, a disease with a chronic and inflammatory nature. These antibodies do not appear to have any strict dependency for reactivity except from the presence of the non-genetically encoded amino acid citrulline, which is the result of a posttranslational modification, catalyzed by calcium-dependent peptidylarginine deiminase enzymes. Nevertheless, several amino acids surrounding the citrulline residue notably influence antibody reactivity, especially with a central-Cit-Gly-motif being essential for antibody reactivity. Most importantly, these antibodies have been proposed to be divided into two groups, based on their ability to recognize multiple citrullinated peptides. Thus, an "overlapping" antibody group, which appears to recognize several citrullinated peptides, and a "non-overlapping" antibody group, which only recognizes a limited number of citrullinated peptides, have been proposed. Based on these findings, we suggest that antibodies recognizing several citrullinated targets, also referred to as cross-reactive antibodies, primarily are backbone-dependent, whereas less cross-reactive antibodies primarily depend on the side chains of the amino acids comprising the epitopes for stable antibody-antigen interactions, which reduces the degree of cross-reactivity significantly. Clarifying the reactivity pattern of anti-citrullinated protein antibodies may contribute to determining their true nature of origin.
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27
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Marillet S, Lefranc MP, Boudinot P, Cazals F. Novel Structural Parameters of Ig-Ag Complexes Yield a Quantitative Description of Interaction Specificity and Binding Affinity. Front Immunol 2017; 8:34. [PMID: 28232828 PMCID: PMC5298999 DOI: 10.3389/fimmu.2017.00034] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 01/09/2017] [Indexed: 11/13/2022] Open
Abstract
Antibody–antigen complexes challenge our understanding, as analyses to date failed to unveil the key determinants of binding affinity and interaction specificity. We partially fill this gap based on novel quantitative analyses using two standardized databases, the IMGT/3Dstructure-DB and the structure affinity benchmark. First, we introduce a statistical analysis of interfaces which enables the classification of ligand types (protein, peptide, and chemical; cross-validated classification error of 9.6%) and yield binding affinity predictions of unprecedented accuracy (median absolute error of 0.878 kcal/mol). Second, we exploit the contributions made by CDRs in terms of position at the interface and atomic packing properties to show that in general, VH CDR3 and VL CDR3 make dominant contributions to the binding affinity, a fact also shown to be consistent with the enthalpy–entropy compensation associated with preconfiguration of CDR3. Our work suggests that the affinity prediction problem could be partially solved from databases of high resolution crystal structures of complexes with known affinity.
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Affiliation(s)
- Simon Marillet
- VIM, INRA and Université Paris-Saclay, Jouy-en-josas, France; Université Côte d'Azur and Inria, Sophia Antipolis, France
| | | | - Pierre Boudinot
- VIM, INRA and Université Paris-Saclay , Jouy-en-josas , France
| | - Frédéric Cazals
- Université Côte d'Azur and Inria , Sophia Antipolis , France
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Trier NH, Holm BE, Slot O, Locht H, Lindegaard H, Svendsen A, Houen G. Physical Characteristics of a Citrullinated Pro-Filaggrin Epitope Recognized by Anti-Citrullinated Protein Antibodies in Rheumatoid Arthritis Sera. PLoS One 2016; 11:e0168542. [PMID: 28002483 PMCID: PMC5176188 DOI: 10.1371/journal.pone.0168542] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 11/16/2016] [Indexed: 11/18/2022] Open
Abstract
Rheumatoid arthritis (RA) is an autoimmune disease of complex etiology. A characteristic feature of a subset of RA is the presence of anti-citrullinated protein antibodies (ACPA), which correlate with a progressive disease course. In this study, we employed streptavidin capture enzyme-linked immunosorbent assay to analyze ACPA reactivity. Using the pro-filaggrin peptide HQCHQEST-Cit-GRSRGRCGRSGS, as template, we analyzed the reactivity of RA sera and healthy donor sera to various peptides in order to determine the physical characteristics of the citrullinated pro-filaggrin epitope and to examine whether biotin labelling influence antibody recognition. The full-length cyclic pro-filaggrin peptide and a linear form with a N-terminal biotin, was recognized to the same level, whereas, a notable difference in ACPA reactivity to the linear peptides with a C-terminal biotin was found, probably due to steric hindrance. Screening of linear and cyclic truncated peptides, revealed that small cyclic peptides containing 10–12 amino acids are favored over the linear. Moreover, the charged amino acids C-terminal to citrulline were found to be essential for antibody reactivity, most important was the charged amino acid in position 4 C-terminal to citrulline. Collectively, peptide structure, length, the presence of charged amino acids and biotin labelling markedly influence antibody reactivity. In relation to the clinical diagnostics of ACPA, these findings may reflect the differences in diagnostic assays used for detection of ACPA, which relates to differences in sensitivity and specificity dependent on the assay applied.
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Affiliation(s)
- Nicole Hartwig Trier
- Department of Autoimmunology and Biomarkers, Statens Serum Institut, Artillerivej, Copenhagen S, Denmark
- * E-mail:
| | - Bettina Eide Holm
- Department of Autoimmunology and Biomarkers, Statens Serum Institut, Artillerivej, Copenhagen S, Denmark
| | - Ole Slot
- Department of Rheumatology, Glostrup Hospital, Nordre Ringvej, Glostrup, Denmark
| | - Henning Locht
- Department of Rheumatology, Frederiksberg Hospital, Nordre Fasanvej, Frederiksberg, Denmark
| | - Hanne Lindegaard
- Department of Rheumatology, Odense University Hospital, Søndre Boulevard, Odense C, Denmark
| | - Anders Svendsen
- Department of Epidemiology, Biostatistics and Bio-demography, Institute of Public Health, University of Southern Denmark, Campusvej, Odense M, Denmark
| | - Gunnar Houen
- Department of Autoimmunology and Biomarkers, Statens Serum Institut, Artillerivej, Copenhagen S, Denmark
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Usman Mirza M, Rafique S, Ali A, Munir M, Ikram N, Manan A, Salo-Ahen OMH, Idrees M. Towards peptide vaccines against Zika virus: Immunoinformatics combined with molecular dynamics simulations to predict antigenic epitopes of Zika viral proteins. Sci Rep 2016; 6:37313. [PMID: 27934901 PMCID: PMC5146661 DOI: 10.1038/srep37313] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 10/27/2016] [Indexed: 12/16/2022] Open
Abstract
The recent outbreak of Zika virus (ZIKV) infection in Brazil has developed to a global health concern due to its likely association with birth defects (primary microcephaly) and neurological complications. Consequently, there is an urgent need to develop a vaccine to prevent or a medicine to treat the infection. In this study, immunoinformatics approach was employed to predict antigenic epitopes of Zika viral proteins to aid in development of a peptide vaccine against ZIKV. Both linear and conformational B-cell epitopes as well as cytotoxic T-lymphocyte (CTL) epitopes were predicted for ZIKV Envelope (E), NS3 and NS5 proteins. We further investigated the binding interactions of altogether 15 antigenic CTL epitopes with three class I major histocompatibility complex (MHC I) proteins after docking the peptides to the binding groove of the MHC I proteins. The stability of the resulting peptide-MHC I complexes was further studied by molecular dynamics simulations. The simulation results highlight the limits of rigid-body docking methods. Some of the antigenic epitopes predicted and analyzed in this work might present a preliminary set of peptides for future vaccine development against ZIKV.
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Affiliation(s)
- Muhammad Usman Mirza
- Center for Research in Molecular Medicine (CRiMM), The University of Lahore, Pakistan
| | - Shazia Rafique
- Centre for Applied Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Amjad Ali
- Centre for Applied Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Mobeen Munir
- Division of Science and Technology, University of Education Lahore, Pakistan
| | - Nazia Ikram
- Institute of Molecular Biology and Biotechnology (IMBB), The University of Lahore, Pakistan
| | - Abdul Manan
- Institute of Molecular Biology and Biotechnology (IMBB), The University of Lahore, Pakistan
| | - Outi M. H. Salo-Ahen
- Structural Bioinformatics Laboratory, Faculty of Science and Engineering, Biochemistry, Åbo Akademi University, Turku, Finland
- Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Pharmacy, Åbo Akademi University, Turku, Finland
| | - Muhammad Idrees
- Centre for Applied Molecular Biology, University of the Punjab, Lahore, Pakistan
- Vice Chancellor Hazara University, Mansehra, Pakistan
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Sabah SN, Gazi MA, Sthity RA, Husain AB, Quyyum SA, Rahman M, Islam MR. Designing of Epitope-Focused Vaccine by Targeting E6 and E7 Conserved Protein Sequences: An Immuno-Informatics Approach in Human Papillomavirus 58 Isolates. Interdiscip Sci 2016; 10:251-260. [PMID: 27640170 DOI: 10.1007/s12539-016-0184-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 08/02/2016] [Accepted: 09/02/2016] [Indexed: 10/21/2022]
Abstract
Human papillomavirus (HPV) is a DNA virus that belongs to the papillomavirus family and is capable of infecting humans. Currently, few vaccines are available to prevent infection by HPV. However, they are not so much effective and provide little benefit to women who have already been infected with HPV. The aim of this study was to design epitope-based vaccines of HPV58 by targeting E6 and E7 proteins of HPV58. Proteomic sequences were retrieved from different isolates at different time periods and later analyzed by performing alignment of these sequences. To ensure the capacity of humoral and cell-mediated immunity, both B cell and T cell immunity were checked for the peptides. For E6 protein, the peptide sequence from 48 to 54 amino acids and one 9-m epitope ETSVHEIEL were the most potential B cell and T cell epitopes, respectively. This peptide could interact with as many as eight MHC-1 alleles and showed high population coverage up to 90.31 %. On the other hand, the peptide region for the E7 protein ranged from 27 to 33 amino acids and two 9-m epitopes QAQPATANY, SSDEDEIGL were found as the most potential B cell and T cell epitopes, respectively. The peptide sequences could interact with as many as seven MHC-1 alleles and showed population coverage up to 90.31 %. Furthermore, conservancy analysis was also performed using in silico tools and showed a conservancy of 100 % for all the selected epitopes. In addition to this, the allergenicity of the epitopes was also evaluated. Although the study requires further in vitro and in vivo screening, this epitope-focused peptide vaccine designing opens up a new skyline that holds a prospective future in HPV research.
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Affiliation(s)
| | - Md Amran Gazi
- Nutrition and Clinical Services Division, Centre for Nutrition and Food Security, International Centre for Diarrhoeal Disease Research, GPO Box 128, Dhaka, 1000, Bangladesh.
| | - Rahvia Alam Sthity
- Immunobiology, Nutrition and Toxicology Laboratory, International Centre for Diarrheal Disease Research, Dhaka, Bangladesh
| | - Amena Binte Husain
- Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka, Bangladesh
| | - Salwa Abdul Quyyum
- Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka, Bangladesh
| | - Mustafizur Rahman
- Center for Bio-Medical Research, Manarat University, Dhaka, Bangladesh
| | - Md Rezaul Islam
- International Max Planck Research School, University of Göttingen, 37075, Göttingen, Germany.
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31
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Hossain MU, Hashem A, Keya CA, Salimullah M. Therapeutics Insight with Inclusive Immunopharmacology Explication of Human Rotavirus A for the Treatment of Diarrhea. Front Pharmacol 2016; 7:153. [PMID: 27445802 PMCID: PMC4917548 DOI: 10.3389/fphar.2016.00153] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Accepted: 05/27/2016] [Indexed: 01/02/2023] Open
Abstract
Rotavirus is the most common cause of severe infant and childhood diarrhea worldwide, and the morbidity and mortality rate is going to be outnumbered in developing countries like Bangladesh. To mitigate this substantial burden of disease, new therapeutics such as vaccine and drug are swiftly required against rotavirus. The present therapeutics insight study was performed with comprehensive immunoinformatics and pharmacoinformatics approach. T and B-cell epitopes were assessed in the conserved region of outer capsid protein VP4 among the highly reviewed strains from different countries including Bangladesh. The results suggest that epitope SU1 (TLKNLNDNY) could be an ideal candidate among the predicted five epitopes for both T and B-cell epitopes for the development of universal vaccine against rotavirus. This research also suggests five novel drug compounds from medicinal plant Rhizophora mucronata Lamk. for better therapeutics strategies against rotavirus diarrhea based on 3D structure building, pharmacophore, ADMET, and QSAR properties. The exact mode of action between drug compounds and target protein VP4 were revealed by molecular docking analysis. Drug likeness and oral bioavailability further confirmed the effectiveness of the proposed drugs against rotavirus diarrhea. This study might be implemented for experimental validation to facilitate the novel vaccine and drug design.
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Affiliation(s)
- Mohammad Uzzal Hossain
- Department of Biotechnology and Genetic Engineering, Life Science Faculty, Mawlana Bhashani Science and Technology University Tangail, Bangladesh
| | - Abu Hashem
- Microbial Biotechnology Division, National Institute of Biotechnology Dhaka, Bangladesh
| | - Chaman Ara Keya
- Department of Biology and Chemistry, North South University Dhaka, Bangladesh
| | - Md Salimullah
- Molecular Biotechnology Division, National Institute of Biotechnology Dhaka, Bangladesh
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32
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Oany AR, Sharmin T, Chowdhury AS, Jyoti TP, Hasan MA. Highly conserved regions in Ebola virus RNA dependent RNA polymerase may be act as a universal novel peptide vaccine target: a computational approach. In Silico Pharmacol 2015; 3:7. [PMID: 26820892 PMCID: PMC4529428 DOI: 10.1186/s40203-015-0011-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 07/22/2015] [Indexed: 11/10/2022] Open
Abstract
Purpose Ebola virus (EBOV) is such kind of virus which is responsible for 23,825 cases and 9675 deaths worldwide only in 2014 and with an average diseases fatality rate between 25 % and 90 %. Although, medical technology has tried to handle the problems, there is no Food and Drug Administration (FDA)-approved therapeutics or vaccines available for the prevention, post exposure, or treatment of Ebola virus disease (EVD). Methods In the present study, we used the immunoinformatics approach to design a potential epitope-based vaccine against the RNA-dependent RNA polymerase-L of EBOV. BioEdit v7.2.3 sequence alignment editor, Jalview v2 and CLC Sequence Viewer v7.0.2 were used for the initial sequence analysis for securing the conservancy from the sequences. Later the Immune Epitope Database and Analysis Resource (IEDB-AR) was used for the identification of T-cell and B-cellepitopes associated with type I and II major histocompatibility complex molecules analysis. Finally, the population coverage analysis was employed. Results The core epitope “FRYEFTAPF” was found to be the most potential one, with 100 % conservancy among all the strains of EBOV. It also interacted with both type I and II major histocompatibility complex molecules and is considered as nonallergenic in nature. Finally, with impressive cumulative population coverage of 99.87 % for the both MHC-I and MHC-II class throughout the world population was found for the proposed epitope. Conclusion To end, the projected peptide gave us a solid stand to propose for vaccine consideration and that might be experimented for its potency in eliciting immunity through humoral and cell mediated immune responses in vitro and in vivo. Electronic supplementary material The online version of this article (doi:10.1186/s40203-015-0011-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Arafat Rahman Oany
- Department of Biotechnology and Genetic Engineering, Faculty of Life Science, Mawlana Bhashani Science and Technology University, Santosh, Tangail-1902, Bangladesh
| | - Tahmina Sharmin
- Department of Biotechnology and Genetic Engineering, Faculty of Life Science, Mawlana Bhashani Science and Technology University, Santosh, Tangail-1902, Bangladesh
| | - Afrin Sultana Chowdhury
- Department of Genetic Engineering and Biotechnology, Faculty of Biological Sciences, University of Chittagong, Chittagong-4331, Bangladesh
| | - Tahmina Pervin Jyoti
- Biotechnology and Genetic Engineering Discipline, Life Science School, Khulna University, Khulna-9208, Bangladesh
| | - Md Anayet Hasan
- Department of Genetic Engineering and Biotechnology, Faculty of Biological Sciences, University of Chittagong, Chittagong-4331, Bangladesh.
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Kaur H, Salunke DM. Antibody promiscuity: Understanding the paradigm shift in antigen recognition. IUBMB Life 2015; 67:498-505. [DOI: 10.1002/iub.1397] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 06/16/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Harmeet Kaur
- Regional Centre for Biotechnology, Biotech Science Cluster; Faridabad 121001 Haryana India
- Manipal University; 576104 Karnataka India
| | - Dinakar M. Salunke
- Regional Centre for Biotechnology, Biotech Science Cluster; Faridabad 121001 Haryana India
- National Institute of Immunology; New Delhi 110067 India
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34
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Oany AR, Ahmad SAI, Hossain MU, Jyoti TP. Identification of highly conserved regions in L-segment of Crimean-Congo hemorrhagic fever virus and immunoinformatic prediction about potential novel vaccine. Adv Appl Bioinform Chem 2015; 8:1-10. [PMID: 25609983 PMCID: PMC4293217 DOI: 10.2147/aabc.s75250] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne zoonotic viral disease with a disease fatality rate between 15% and 70%. Despite the wide range of distribution, the virus (CCHFV) is basically endemic in Africa, Asia, eastern Europe, and the Middle East. Acute febrile illness associated with petechiae, disseminated intravascular coagulation, and multiple-organ failure are the main symptoms of the disease. With all these fatal effects, CCHFV is considered a huge threat as no successful therapeutic approach is currently available for the treatment of this disease. In the present study, we have used the immunoinformatics approach to design a potential epitope-based vaccine against the RNA-dependent RNA polymerase-L of CCHFV. Both the T-cell and B-cell epitopes were assessed, and the epitope "DCSSTPPDR" was found to be the most potential one, with 100% conservancy among all the strains of CCHFV. The epitope was also found to interact with both type I and II major histocompatibility complex molecules and is considered nonallergenic as well. In vivo study of our proposed peptide is advised for novel universal vaccine production, which might be an effective path to prevent CCHF disease.
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Affiliation(s)
- Arafat Rahman Oany
- Department of Biotechnology and Genetic Engineering, Faculty of Life Science, Mawlana Bhashani Science and Technology University, Santosh, Tangail, Bangladesh
| | - Shah Adil Ishtiyaq Ahmad
- Department of Biotechnology and Genetic Engineering, Faculty of Life Science, Mawlana Bhashani Science and Technology University, Santosh, Tangail, Bangladesh
| | - Mohammad Uzzal Hossain
- Department of Biotechnology and Genetic Engineering, Faculty of Life Science, Mawlana Bhashani Science and Technology University, Santosh, Tangail, Bangladesh
| | - Tahmina Pervin Jyoti
- Biotechnology and Genetic Engineering Discipline, Life Science School, Khulna University, Khulna, Bangladesh
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35
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Muhamad A, Ho KL, Abdul Rahman MB, Tejo BA, Uhrín D, Tan WS. Hepatitis B virus peptide inhibitors: solution structures and interactions with the viral capsid. Org Biomol Chem 2015; 13:7780-9. [DOI: 10.1039/c5ob00449g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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36
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Oany AR, Emran AA, Jyoti TP. Design of an epitope-based peptide vaccine against spike protein of human coronavirus: an in silico approach. DRUG DESIGN DEVELOPMENT AND THERAPY 2014; 8:1139-49. [PMID: 25187696 PMCID: PMC4149408 DOI: 10.2147/dddt.s67861] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Human coronavirus (HCoV), a member of Coronaviridae family, is the
causative agent of upper respiratory tract infections and “atypical
pneumonia”. Despite severe epidemic outbreaks on several occasions and lack of
antiviral drug, not much progress has been made with regard to an epitope-based vaccine
designed for HCoV. In this study, a computational approach was adopted to identify a
multiepitope vaccine candidate against this virus that could be suitable to trigger a
significant immune response. Sequences of the spike proteins were collected from a protein
database and analyzed with an in silico tool, to identify the most immunogenic protein.
Both T cell immunity and B cell immunity were checked for the peptides to ensure that they
had the capacity to induce both humoral and cell-mediated immunity. The peptide sequence
from 88–94 amino acids and the sequence KSSTGFVYF were found as the most potential
B cell and T cell epitopes, respectively. Furthermore, conservancy analysis was also done
using in silico tools and showed a conservancy of 64.29% for all epitopes. The peptide
sequence could interact with as many as 16 human leukocyte antigens (HLAs) and showed high
cumulative population coverage, ranging from 75.68% to 90.73%. The epitope was further
tested for binding against the HLA molecules, using in silico docking techniques, to
verify the binding cleft epitope interaction. The allergenicity of the epitopes was also
evaluated. This computational study of design of an epitope-based peptide vaccine against
HCoVs allows us to determine novel peptide antigen targets in spike proteins on intuitive
grounds, albeit the preliminary results thereof require validation by in vitro and in vivo
experiments.
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Affiliation(s)
- Arafat Rahman Oany
- Department of Biotechnology and Genetic Engineering, Life Science Faculty, Mawlana Bhashani Science and Technology University, Tangail, Bangladesh
| | - Abdullah-Al Emran
- Department of Biotechnology and Genetic Engineering, Life Science Faculty, Mawlana Bhashani Science and Technology University, Tangail, Bangladesh ; Translational Research Institute, University of Queensland, Brisbane, Australia
| | - Tahmina Pervin Jyoti
- Biotechnology and Genetic Engineering Discipline, Life Science School, Khulna University, Khulna, Bangladesh
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Gill J, Jayaswal P, Salunke DM. Antigen exposure leads to rigidification of germline antibody combining site. J Bioinform Comput Biol 2014; 12:1450006. [DOI: 10.1142/s0219720014500061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Immune complexes involving diverse antigens and corresponding antibodies were analyzed for mapping conformational transitions of an antibody before antigen binding, upon antigen binding and after antigen release. Molecular dynamics simulations of the two comprehensive datasets consisting of the antigen-free and antigen-bound structures of the germline antibodies 36-65 and BBE6.12H3 provided mechanistic model of antigen encounter by primary antibodies. While native germline antibodies exhibit substantial mobility in the antigen-combining sites, their antigen-bound states exhibit relatively rigid conformations, even in the absence of the antigen suggesting preservation of the structural state after antigen release. It is proposed that acquired rigidity by a germline antibody upon antigen binding may be the first step in affinity maturation in favor of that antigen.
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Affiliation(s)
- Jasmita Gill
- Regional Centre for Biotechnology, 180 Udyog Vihar Phase 1, Gurgaon 122016, Gurgaon, India
| | - Praapti Jayaswal
- Regional Centre for Biotechnology, 180 Udyog Vihar Phase 1, Gurgaon 122016, Gurgaon, India
| | - Dinakar M. Salunke
- Regional Centre for Biotechnology, 180 Udyog Vihar Phase 1, Gurgaon 122016, Gurgaon, India
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
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Khan T, Salunke DM. Adjustable locks and flexible keys: plasticity of epitope-paratope interactions in germline antibodies. THE JOURNAL OF IMMUNOLOGY 2014; 192:5398-405. [PMID: 24790145 DOI: 10.4049/jimmunol.1302143] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Ag recognition by independent primary Abs against a small flexible Ag with overlapping epitopes was analyzed to address the determinants of Ag specificity during the initial encounter. Crystal structures of two distinct dodecapeptide Ags, GDPRPSYISHLL and PPYPAWHAPGNI, in complex with the germline mAb 36-65 were determined and compared with the structures of the same Ags bound to another independent germline mAb, BBE6.12H3. For each peptide Ag, the two germline mAbs recognized overlapping epitopes, but in different topologies. The peptide structures differed, and the two paratopes attained discrete conformations, leading to different surface topologies, in a mode that can be described as adjustable locks and flexible keys. This is in contrast to mature mAbs, in which conformational convergence of different paratopes while binding to a common epitope in a similar conformation has been reported. These results suggest that the primary immune receptor repertoire is highly versatile as compared with its mature counterpart. Germline and mature mAbs adopt distinct mechanisms for recognizing a flexible epitope. Whereas conservation of conformational repertoire is a key characteristic of mature mAbs achieved through affinity maturation, the germline mAbs, at the initial stages of Ag encounter, maintain substantial plasticity, accommodating a broad specificity repertoire.
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Affiliation(s)
- Tarique Khan
- National Institute of Immunology, New Delhi 110067, India; and
| | - Dinakar M Salunke
- National Institute of Immunology, New Delhi 110067, India; and Regional Centre for Biotechnology, Gurgaon 122016, India
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39
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Backbone flexibility of CDR3 and immune recognition of antigens. J Mol Biol 2013; 426:1583-99. [PMID: 24380763 DOI: 10.1016/j.jmb.2013.12.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 12/03/2013] [Accepted: 12/19/2013] [Indexed: 11/22/2022]
Abstract
Conformational entropy is an important component of protein-protein interactions; however, there is no reliable method for computing this parameter. We have developed a statistical measure of residual backbone entropy in folded proteins by using the ϕ-ψ distributions of the 20 amino acids in common secondary structures. The backbone entropy patterns of amino acids within helix, sheet or coil form clusters that recapitulate the branching and hydrogen bonding properties of the side chains in the secondary structure type. The same types of residues in coil and sheet have identical backbone entropies, while helix residues have much smaller conformational entropies. We estimated the backbone entropy change for immunoglobulin complementarity-determining regions (CDRs) from the crystal structures of 34 low-affinity T-cell receptors and 40 high-affinity Fabs as a result of the formation of protein complexes. Surprisingly, we discovered that the computed backbone entropy loss of only the CDR3, but not all CDRs, correlated significantly with the kinetic and affinity constants of the 74 selected complexes. Consequently, we propose a simple algorithm to introduce proline mutations that restrict the conformational flexibility of CDRs and enhance the kinetics and affinity of immunoglobulin interactions. Combining the proline mutations with rationally designed mutants from a previous study led to 2400-fold increase in the affinity of the A6 T-cell receptor for Tax-HLAA2. However, this mutational scheme failed to induce significant binding changes in the already-high-affinity C225-Fab/huEGFR interface. Our results will serve as a roadmap to formulate more effective target functions to design immune complexes with improved biological functions.
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40
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Hasan MA, Hossain M, Alam MJ. A computational assay to design an epitope-based Peptide vaccine against saint louis encephalitis virus. Bioinform Biol Insights 2013; 7:347-55. [PMID: 24324329 PMCID: PMC3855041 DOI: 10.4137/bbi.s13402] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Saint Louis encephalitis virus, a member of the flaviviridae subgroup, is a culex mosquito-borne pathogen. Despite severe epidemic outbreaks on several occasions, not much progress has been made with regard to an epitope-based vaccine designed for Saint Louis encephalitis virus. The envelope proteins were collected from a protein database and analyzed with an in silico tool to identify the most immunogenic protein. The protein was then verified through several parameters to predict the T-cell and B-cell epitopes. Both T-cell and B-cell immunity were assessed to determine that the protein can induce humoral as well as cell-mediated immunity. The peptide sequence from 330-336 amino acids and the sequence REYCYEATL from the position 57 were found as the most potential B-cell and T-cell epitopes, respectively. Furthermore, as an RNA virus, one important thing was to establish the epitope as a conserved one; this was also done by in silico tools, showing 63.51% conservancy. The epitope was further tested for binding against the HLA molecule by computational docking techniques to verify the binding cleft epitope interaction. However, this is a preliminary study of designing an epitope-based peptide vaccine against Saint Louis encephalitis virus; the results awaits validation by in vitro and in vivo experiments.
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Affiliation(s)
- Md Anayet Hasan
- Department of Genetic Engineering and Biotechnology, Faculty of Biological Sciences, University of Chittagong, Chittagong, Bangladesh
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41
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Willis JR, Briney BS, DeLuca SL, Crowe JE, Meiler J. Human germline antibody gene segments encode polyspecific antibodies. PLoS Comput Biol 2013; 9:e1003045. [PMID: 23637590 PMCID: PMC3636087 DOI: 10.1371/journal.pcbi.1003045] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 03/15/2013] [Indexed: 11/25/2022] Open
Abstract
Structural flexibility in germline gene-encoded antibodies allows promiscuous binding to diverse antigens. The binding affinity and specificity for a particular epitope typically increase as antibody genes acquire somatic mutations in antigen-stimulated B cells. In this work, we investigated whether germline gene-encoded antibodies are optimal for polyspecificity by determining the basis for recognition of diverse antigens by antibodies encoded by three VH gene segments. Panels of somatically mutated antibodies encoded by a common VH gene, but each binding to a different antigen, were computationally redesigned to predict antibodies that could engage multiple antigens at once. The Rosetta multi-state design process predicted antibody sequences for the entire heavy chain variable region, including framework, CDR1, and CDR2 mutations. The predicted sequences matched the germline gene sequences to a remarkable degree, revealing by computational design the residues that are predicted to enable polyspecificity, i.e., binding of many unrelated antigens with a common sequence. The process thereby reverses antibody maturation in silico. In contrast, when designing antibodies to bind a single antigen, a sequence similar to that of the mature antibody sequence was returned, mimicking natural antibody maturation in silico. We demonstrated that the Rosetta computational design algorithm captures important aspects of antibody/antigen recognition. While the hypervariable region CDR3 often mediates much of the specificity of mature antibodies, we identified key positions in the VH gene encoding CDR1, CDR2, and the immunoglobulin framework that are critical contributors for polyspecificity in germline antibodies. Computational design of antibodies capable of binding multiple antigens may allow the rational design of antibodies that retain polyspecificity for diverse epitope binding.
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Affiliation(s)
- Jordan R. Willis
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Institute for Chemical Biology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Bryan S. Briney
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Samuel L. DeLuca
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Institute for Chemical Biology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - James E. Crowe
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Jens Meiler
- Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, United States of America
- Institute for Chemical Biology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
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42
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Roggen EL. Recent developments with B-cell epitope identification for predictive studies. J Immunotoxicol 2012; 3:137-49. [PMID: 18958694 DOI: 10.1080/15476910600845690] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
This review discusses currently available methods for predicting B-cell epitopes on proteins. The use of animals for assessing protein immunogenicity is addressed primarily to highlight the differences in B- and T-cell epitope recognition between species. These differences have to be considered when interpreting potential B-cell epitopes identified by the methods addressed here. "In vitro alternatives" focuses on the strengths and limitations of peptide-based technologies. Three types of computer-based methods for identifying potential B-cell epitopes are discussed: (i) methods applying physico-chemical and structural propensity scales for predicting linear epitopes from the primary structure of a protein, (ii) comparative methods basing prediction upon amino acid sequence and structural similarities between antigenically known and unknown proteins, and (iii) a method combining structural features with a B-cell epitope motif database for predicting linear and conformational antigenic determinants. With respect to human safety, the usefulness of antibody-based tests is limited to comparative studies between an antigenically known protein and variants thereof. Similarly, computer-based methods using data mining can address similarities in B-cell epitope profiles between related proteins, if a proper cut off can be defined for the minimal amino acid sequence similarity required for obtaining an acceptable accuracy. Among the physico-chemical and structural scales, scales identifying in a protein hairpin and non-specific turns seem useful for predicting epitopes with a continuous primary binding site. When conformational epitopes have to be identified as well, a novel computer-based tool seems to be the most promising alternative to X-ray crystallography. However, both methods remain to be extensively evaluated and validated. Thus, promising tools for B-cell epitope identification have been developed. But, no validated method for B-cell epitope identification on antigenically unknown proteins is available yet.
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43
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Meng W, Yunk L, Wang LS, Maganty A, Xue E, Cohen PL, Eisenberg RA, Weigert MG, Mancini SJC, Prak ETL. Selection of individual VH genes occurs at the pro-B to pre-B cell transition. THE JOURNAL OF IMMUNOLOGY 2011; 187:1835-44. [PMID: 21746964 DOI: 10.4049/jimmunol.1100207] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
B cells are subjected to selection at multiple checkpoints during their development. The selection of Ab H chains is difficult to study because of the large diversity of the CDR3. To study the selection of individual Ab H chain V region genes (V(H)), we performed CDR3 spectratyping of ∼ 75-300 rearrangements per individual V(H) in C57BL6/J mice. We measured the fraction of rearrangements that were in-frame in B cell DNA. We demonstrate that individual V(H)s have different fractions of in-frame rearrangements (IF fractions) ranging from 10 to 90% and that these IF fractions are reproducible in different mice. For most V(H)s, the IF fraction in pro-B cells approximated 33% and then shifted to the nearly final (mature) B cell value by the cycling pre-B cell stage. The frequency of high in-frame (IF) V(H) usage increased in cycling pre-B cells compared with that in pro-B cells, whereas this did not occur for low IF V(H)s. The IF fraction did not shift as much in BCR-expressing B cells and was minimally affected by L chain usage for most V(H). High IF clan II/III V(H)s share more positively charged CDR2 sequences, whereas high IF clan I J558 CDR2 sequences are diverse. These data indicate that individual V(H)s are subjected to differential selection, that V(H) IF fraction is mainly established through pre-BCR-mediated selection, that it may operate differently in clan I versus II/III V(H)s, and that it has a lasting influence on the Ab repertoire.
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Affiliation(s)
- Wenzhao Meng
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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44
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Fenalti G, Buckle AM. Structural biology of the GAD autoantigen. Autoimmun Rev 2010; 9:148-52. [DOI: 10.1016/j.autrev.2009.05.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2009] [Accepted: 05/12/2009] [Indexed: 10/20/2022]
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45
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Agostino M, Sandrin MS, Thompson PE, Yuriev E, Ramsland PA. In silico analysis of antibody-carbohydrate interactions and its application to xenoreactive antibodies. Mol Immunol 2009; 47:233-46. [PMID: 19828202 DOI: 10.1016/j.molimm.2009.09.031] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2009] [Revised: 09/11/2009] [Accepted: 09/17/2009] [Indexed: 11/26/2022]
Abstract
Antibody-carbohydrate interactions play central roles in stimulating adverse immune reactions. The most familiar example of such a process is the reaction observed in ABO-incompatible blood transfusion and organ transplantation. The ABO blood groups are defined by the presence of specific carbohydrates expressed on the surface of red blood cells. Preformed antibodies in the incompatible recipient (i.e., different blood groups) recognize cells exhibiting host-incompatible ABO system antigens and proceed to initiate lysis of the incompatible cells. Pig-to-human xenotransplantation presents a similar immunological barrier. Antibodies present in humans recognize carbohydrate antigens on the surface of pig organs as foreign and proceed to initiate hyperacute xenograft rejection. The major carbohydrate xenoantigens all bear terminal Gal alpha(1,3)Gal epitopes (or alphaGal). In this study, we have developed and validated a site mapping technique to investigate protein-ligand recognition and applied it to antibody-carbohydrate systems. This site mapping technique involves the use of molecular docking to generate a series of antibody-carbohydrate complexes, followed by analysis of the hydrogen bonding and van der Waals interactions occurring in each complex. The technique was validated by application to a series of antibody-carbohydrate crystal structures. In each case, the majority of interactions made in the crystal structure complex were able to be reproduced. The technique was then applied to investigate xenoantigen recognition by a panel of monoclonal anti-alphaGal antibodies. The results indicate that there is a significant overlap of the antibody regions engaging the xenoantigens across the panel. Likewise, similar regions of the xenoantigens interact with the antibodies.
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Affiliation(s)
- Mark Agostino
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
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46
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Uysal H, Bockermann R, Nandakumar KS, Sehnert B, Bajtner E, Engström A, Serre G, Burkhardt H, Thunnissen MMGM, Holmdahl R. Structure and pathogenicity of antibodies specific for citrullinated collagen type II in experimental arthritis. ACTA ACUST UNITED AC 2009; 206:449-62. [PMID: 19204106 PMCID: PMC2646582 DOI: 10.1084/jem.20081862] [Citation(s) in RCA: 179] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Antibodies to citrulline-modified proteins have a high diagnostic value in rheumatoid arthritis (RA). However, their biological role in disease development is still unclear. To obtain insight into this question, a panel of mouse monoclonal antibodies was generated against a major triple helical collagen type II (CII) epitope (position 359-369; ARGLTGRPGDA) with or without arginines modified by citrullination. These antibodies bind cartilage and synovial tissue, and mediate arthritis in mice. Detection of citrullinated CII from RA patients' synovial fluid demonstrates that cartilage-derived CII is indeed citrullinated in vivo. The structure determination of a Fab fragment of one of these antibodies in complex with a citrullinated peptide showed a surprising beta-turn conformation of the peptide and provided information on citrulline recognition. Based on these findings, we propose that autoimmunity to CII, leading to the production of antibodies specific for both native and citrullinated CII, is an important pathogenic factor in the development of RA.
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Affiliation(s)
- Hüseyin Uysal
- Center for Molecular Protein Science, Biomedical Center I11, Lund University, 221 00 Lund, Sweden
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47
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Lapelosa M, Gallicchio E, Arnold GF, Arnold E, Levy RM. In silico vaccine design based on molecular simulations of rhinovirus chimeras presenting HIV-1 gp41 epitopes. J Mol Biol 2009; 385:675-91. [PMID: 19026659 PMCID: PMC2649764 DOI: 10.1016/j.jmb.2008.10.089] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 09/15/2008] [Accepted: 10/31/2008] [Indexed: 11/28/2022]
Abstract
A cluster of promising epitopes for the development of human immunodeficiency virus (HIV) vaccines is located in the membrane-proximal external region (MPER) of the gp41 subunit of the HIV envelope spike structure. The crystal structure of the peptide corresponding to the so-called ELDKWA epitope (HIV-1 HxB2 gp41 residues 662-668), in complex with the corresponding broadly neutralizing human monoclonal antibody 2F5, provides a target for structure-based vaccine design strategies aimed at finding macromolecular carriers that are able to present this MPER-derived epitope with optimal antigenic activity. To this end, a series of replica exchange molecular dynamics computer simulations was conducted to characterize the distributions of conformations of ELDKWA-based epitopes inserted into a rhinovirus carrier and to identify those with the highest fraction of conformations that are able to bind 2F5. The length, hydrophobic character, and precise site of insertion were found to be critical for achieving structural similarity to the target crystal structure. A construct with a high degree of complementarity to the corresponding determinant region of 2F5 was obtained. This construct was employed to build a high-resolution structural model of the complex between the 2F5 antibody and the chimeric human rhinovirus type 14:HIV-1 ELDKWA virus particle. Additional simulations, which were conducted to study the conformational propensities of the ELDKWA region in solution, confirm the hypothesis that the ELDKWA region of gp41 is highly flexible and capable of assuming helical conformations (as in the postfusion helical bundle structure) and beta-turn conformations (as in the complex with the 2F5 antibody). These results also suggest that the ELDKWA epitope can be involved in intramolecular--and likely intermolecular--hydrophobic interactions. This tendency offers an explanation for the observation that mutations decreasing the hydrophobic character of the MPER in many cases result in conformational changes that increase the affinity of this region for the 2F5 antibody.
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Affiliation(s)
- Mauro Lapelosa
- BioMaPS Institute for Quantitative Biology, Rutgers University, Piscataway, NJ 08854, USA
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48
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Tong JC, Song CM, Tan PTJ, Ren EC, Sinha AA. BEID: database for sequence-structure-function information on antigen-antibody interactions. Bioinformation 2008; 3:58-60. [PMID: 19238231 PMCID: PMC2637950 DOI: 10.6026/97320630003058] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Accepted: 09/21/2008] [Indexed: 11/23/2022] Open
Abstract
The B-cell Epitope Interaction Database (BEID;
http://datam.i2r.a-star.edu.sg/BEID) is an open-access database describing sequence-structure-function
information on immunoglobulin (Ig)-antigen interactions. The current version of the database contains 164 antigens, 126 Ig
and 189 Ig-antigen complexes extracted from the Protein Data Bank (PDB). Each entry is manually verified, classified, and
analyzed for intermolecular interactions between antigens and the corresponding bound Ig molecules. Ig-antigen interaction
information that is stored in BEID includes solvent accessibility, hydrogen bonds, non-hydrogen bonds, gap volume, gap index, interface area and contact residues. The database can be searched with a user-friendly search tool and
schematic diagrams for Ig-antigen interactions are available for download in PDF format. The ultimate purpose of BEID is to
enhance the understanding of the rules of engagement between antigen and the corresponding bound Ig molecules. It is also
a precious data source for developing computational predictors for B-cell epitopes.
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Affiliation(s)
- Joo Chuan Tong
- Institute for Infocomm Research, 1 Fusionopolis Way, #21-01 Connexis, South Tower, Singapore.
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Thielges MC, Zimmermann J, Yu W, Oda M, Romesberg FE. Exploring the energy landscape of antibody-antigen complexes: protein dynamics, flexibility, and molecular recognition. Biochemistry 2008; 47:7237-47. [PMID: 18549243 DOI: 10.1021/bi800374q] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The production of antibodies that selectively bind virtually any foreign compound is the hallmark of the immune system. While much is understood about how sequence diversity contributes to this remarkable feat of molecular recognition, little is known about how sequence diversity impacts antibody dynamics, which is also expected to contribute to molecular recognition. Toward this goal, we examined a panel of antibodies elicited to the chromophoric antigen fluorescein. On the basis of isothermal titration calorimetry, we selected six antibodies that bind fluorescein with diverse binding entropies, suggestive of varying contributions of dynamics to molecular recognition. Sequencing revealed that two pairs of antibodies employ homologous heavy chains that were derived from common germline genes, while the other two heavy chains and all six of the light chains were derived from different germline genes and are not homologous. Interestingly, more than half of all the somatic mutations acquired during affinity maturation among the six antibodies are located in positions unlikely to contact fluorescein directly. To quantify and compare the dynamics of the antibody-fluorescein complexes, three-pulse photon echo peak shift and transient grating spectroscopy were employed. All of the antibodies exhibited motions on three distinct time scales, ultrafast motions on the <100 fs time scale, diffusive motions on the picosecond time scale, and motions that occur on time scales longer than nanoseconds and thus appear static. However, the exact frequency of the picosecond time scale motion and the relative contribution of the different motions vary significantly among the antibody-chromophore complexes, revealing a high level of dynamic diversity. Using a hierarchical model, we relate the data to features of the antibodies' energy landscapes as well as their flexibility in terms of elasticity and plasticity. In all, the data provide a consistent picture of antibody flexibility, which interestingly appears to be correlated with binding entropy as well as with germline gene use and the mutations introduced during affinity maturation. The data also provide a gauge of the dynamic diversity of the antibody repertoire and suggest that this diversity might contribute to molecular recognition by facilitating the recognition of the broadest range of foreign molecules.
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Affiliation(s)
- Megan C Thielges
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
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50
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Fenalti G, Hampe CS, Arafat Y, Law RHP, Banga JP, Mackay IR, Whisstock JC, Buckle AM, Rowley MJ. COOH-terminal clustering of autoantibody and T-cell determinants on the structure of GAD65 provide insights into the molecular basis of autoreactivity. Diabetes 2008; 57:1293-301. [PMID: 18184926 DOI: 10.2337/db07-1461] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To gain structural insights into the autoantigenic properties of GAD65 in type 1 diabetes, we analyzed experimental epitope mapping data in the context of the recently determined crystal structures of GAD65 and GAD67, to allow "molecular positioning" of epitope sites for B- and T-cell reactivity. RESEARCH DESIGN AND METHODS Data were assembled from analysis of reported effects of mutagenesis of GAD65 on its reactivity with a panel of 11 human monoclonal antibodies (mAbs), supplemented by use of recombinant Fab to cross-inhibit reactivity with GAD65 by radioimmunoprecipitation of the same mAbs. RESULTS The COOH-terminal region on GAD65 was the major autoantigenic site. B-cell epitopes were distributed within two separate clusters around different faces of the COOH-terminal domain. Inclusion of epitope sites in the pyridoxal phosphate-and NH(2)-terminal domains was attributed to the juxtaposition of all three domains in the crystal structure. Epitope preferences of different mAbs to GAD65 aligned with different clinical expressions of type 1 diabetes. Epitopes for four of five known reactive T-cell sequences restricted by HLA DRB1*0401 were aligned to solvent-exposed regions of the GAD65 structure and colocalized within the two B-cell epitope clusters. The continuous COOH-terminal epitope region of GAD65 was structurally highly flexible and therefore differed markedly from the equivalent region of GAD67. CONCLUSIONS Structural features could explain the differing antigenicity, and perhaps immunogenicity, of GAD65 versus GAD67. The proximity of B- and T-cell epitopes within the GAD65 structure suggests that antigen-antibody complexes may influence antigen processing by accessory cells and thereby T-cell reactivity.
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Affiliation(s)
- Gustavo Fenalti
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
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