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Sweedan A, Cohen Y, Yaron S, Bashouti MY. Binding Capabilities of Different Genetically Engineered pVIII Proteins of the Filamentous M13/Fd Virus and Single-Walled Carbon Nanotubes. NANOMATERIALS 2022; 12:nano12030398. [PMID: 35159743 PMCID: PMC8839290 DOI: 10.3390/nano12030398] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/20/2022] [Accepted: 01/20/2022] [Indexed: 12/12/2022]
Abstract
Binding functional biomolecules to non-biological materials, such as single-walled carbon nanotubes (SWNTs), is a challenging task with relevance for different applications. However, no one has yet undertaken a comparison of the binding of SWNTs to different recombinant filamentous viruses (phages) bioengineered to contain different binding peptides fused to the virus coat proteins. This is important due to the range of possible binding efficiencies and scenarios that may arise when the protein’s amino acid sequence is modified, since the peptides may alter the virus’s biological properties or they may behave differently when they are in the context of being displayed on the virus coat protein; in addition, non-engineered viruses may non-specifically adsorb to SWNTs. To test these possibilities, we used four recombinant phage templates and the wild type. In the first circumstance, we observed different binding capabilities and biological functional alterations; e.g., some peptides, in the context of viral templates, did not bind to SWNTs, although it was proven that the bare peptide did. The second circumstance was excluded, as the wild-type virus was found to hardly bind to the SWNTs. These results may be relevant to the possible use of the virus as a “SWNT shuttle” in nano-scale self-assembly, particularly since the pIII proteins are free to act as binding-directing agents. Therefore, knowledge of the differences between and efficiencies of SWNT binding templates may help in choosing better binding phages or peptides for possible future applications and industrial mass production.
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Affiliation(s)
- Amro Sweedan
- The Ilse-Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel;
- The Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Yachin Cohen
- The Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
- Department of Chemical Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel
- Correspondence: (Y.C.); (S.Y.); (M.Y.B.)
| | - Sima Yaron
- The Russell Berrie Nanotechnology Institute, Technion-Israel Institute of Technology, Haifa 3200003, Israel
- Department of Biotechnology and Food Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel
- Correspondence: (Y.C.); (S.Y.); (M.Y.B.)
| | - Muhammad Y. Bashouti
- The Ilse-Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel;
- Jacob Blaustein Institutes for Desert Research, Sede Boqer Campus, Ben-Gurion University of the Negev, Sede Boqer 8499000, Israel
- Correspondence: (Y.C.); (S.Y.); (M.Y.B.)
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2
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Mertinková P, Mochnáčová E, Bhide K, Kulkarni A, Tkáčová Z, Hruškovicová J, Bhide M. Development of peptides targeting receptor binding site of the envelope glycoprotein to contain the West Nile virus infection. Sci Rep 2021; 11:20131. [PMID: 34635758 PMCID: PMC8505397 DOI: 10.1038/s41598-021-99696-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 09/24/2021] [Indexed: 11/09/2022] Open
Abstract
West Nile virus (WNV), re-emerging neurotropic flavivirus, can cross the blood-brain barrier (BBB) and cause fatal encephalitis and meningitis. Infection of the human brain microvascular endothelial cells (hBMECs), building blocks of the BBB, represents the pivotal step in neuroinvasion. Domain III (DIII) of the envelope (E) glycoprotein is a key receptor-binding domain, thus, it is an attractive target for anti-flavivirus strategies. Here, two combinatorial phage display peptide libraries, Ph.D.-C7C and Ph.D.-12, were panned against receptor-binding site (RBS) on DIII to isolate peptides that could block DIII. From series of pannings, nine peptides (seven 7-mer cyclic and two 12-mer linear) were selected and overexpressed in E. coli SHuffle T5. Presence of disulfide bond in 7-mer peptides was confirmed with thiol-reactive maleimide labeling. Except for linear peptide 19 (HYSWSWIAYSPG), all peptides proved to be DIII binders. Among all peptides, 4 cyclic peptides (CTKTDVHFC, CIHSSTRAC, CTYENHRTC, and CLAQSHPLC) showed significant blocking of the interaction between DIII and hBMECs, and ability to neutralize infection in cultured cells. None of these peptides showed toxic or hemolytic activity. Peptides identified in this study may serve as potential candidates for the development of novel antiviral therapeutics against WNV.
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Affiliation(s)
- Patrícia Mertinková
- grid.412971.80000 0001 2234 6772Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy in Košice, Komenského 73, 04181 Košice, Slovakia
| | - Evelína Mochnáčová
- grid.412971.80000 0001 2234 6772Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy in Košice, Komenského 73, 04181 Košice, Slovakia
| | - Katarína Bhide
- grid.412971.80000 0001 2234 6772Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy in Košice, Komenského 73, 04181 Košice, Slovakia
| | - Amod Kulkarni
- grid.412971.80000 0001 2234 6772Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy in Košice, Komenského 73, 04181 Košice, Slovakia ,grid.419303.c0000 0001 2180 9405Institute of Neuroimmunology of Slovak Academy of Sciences, Dubravska cesta 9, 84510 Bratislava, Slovakia
| | - Zuzana Tkáčová
- grid.412971.80000 0001 2234 6772Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy in Košice, Komenského 73, 04181 Košice, Slovakia
| | - Jana Hruškovicová
- grid.412971.80000 0001 2234 6772Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy in Košice, Komenského 73, 04181 Košice, Slovakia
| | - Mangesh Bhide
- grid.412971.80000 0001 2234 6772Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy in Košice, Komenského 73, 04181 Košice, Slovakia ,grid.419303.c0000 0001 2180 9405Institute of Neuroimmunology of Slovak Academy of Sciences, Dubravska cesta 9, 84510 Bratislava, Slovakia
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Ashkenazy H, Avram O, Ryvkin A, Roitburd-Berman A, Weiss-Ottolenghi Y, Hada-Neeman S, Gershoni JM, Pupko T. Motifier: An IgOme Profiler Based on Peptide Motifs Using Machine Learning. J Mol Biol 2021; 433:167071. [PMID: 34052285 DOI: 10.1016/j.jmb.2021.167071] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 04/26/2021] [Accepted: 05/22/2021] [Indexed: 11/26/2022]
Abstract
Antibodies provide a comprehensive record of the encounters with threats and insults to the immune system. The ability to examine the repertoire of antibodies in serum and discover those that best represent "discriminating features" characteristic of various clinical situations, is potentially very useful. Recently, phage display technologies combined with Next-Generation Sequencing (NGS) produced a powerful experimental methodology, coined "Deep-Panning", in which the spectrum of serum antibodies is probed. In order to extract meaningful biological insights from the tens of millions of affinity-selected peptides generated by Deep-Panning, advanced bioinformatics algorithms are a must. In this study, we describe Motifier, a computational pipeline comprised of a set of algorithms that systematically generates discriminatory peptide motifs based on the affinity-selected peptides identified by Deep-Panning. These motifs are shown to effectively characterize antibody binding activities and through the implementation of machine-learning protocols are shown to accurately classify complex antibody mixtures representing various biological conditions.
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Affiliation(s)
- Haim Ashkenazy
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Oren Avram
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Arie Ryvkin
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Anna Roitburd-Berman
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Yael Weiss-Ottolenghi
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Smadar Hada-Neeman
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Jonathan M Gershoni
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.
| | - Tal Pupko
- The Shmunis School of Biomedicine and Cancer Research, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.
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Mor M, Werbner M, Alter J, Safra M, Chomsky E, Lee JC, Hada-Neeman S, Polonsky K, Nowell CJ, Clark AE, Roitburd-Berman A, Ben-Shalom N, Navon M, Rafael D, Sharim H, Kiner E, Griffis ER, Gershoni JM, Kobiler O, Leibel SL, Zimhony O, Carlin AF, Yaari G, Dessau M, Gal-Tanamy M, Hagin D, Croker BA, Freund NT. Multi-clonal SARS-CoV-2 neutralization by antibodies isolated from severe COVID-19 convalescent donors. PLoS Pathog 2021; 17:e1009165. [PMID: 33571304 PMCID: PMC7877634 DOI: 10.1371/journal.ppat.1009165] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 11/25/2020] [Indexed: 11/19/2022] Open
Abstract
The interactions between antibodies, SARS-CoV-2 and immune cells contribute to the pathogenesis of COVID-19 and protective immunity. To understand the differences between antibody responses in mild versus severe cases of COVID-19, we analyzed the B cell responses in patients 1.5 months post SARS-CoV-2 infection. Severe, and not mild, infection correlated with high titers of IgG against Spike receptor binding domain (RBD) that were capable of ACE2:RBD inhibition. B cell receptor (BCR) sequencing revealed that VH3-53 was enriched during severe infection. Of the 22 antibodies cloned from two severe donors, six exhibited potent neutralization against authentic SARS-CoV-2, and inhibited syncytia formation. Using peptide libraries, competition ELISA and mutagenesis of RBD, we mapped the epitopes of the neutralizing antibodies (nAbs) to three different sites on the Spike. Finally, we used combinations of nAbs targeting different immune-sites to efficiently block SARS-CoV-2 infection. Analysis of 49 healthy BCR repertoires revealed that the nAbs germline VHJH precursors comprise up to 2.7% of all VHJHs. We demonstrate that severe COVID-19 is associated with unique BCR signatures and multi-clonal neutralizing responses that are relatively frequent in the population. Moreover, our data support the use of combination antibody therapy to prevent and treat COVID-19.
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Affiliation(s)
- Michael Mor
- Sackler Faculty of Medicine, Tel Aviv University, Tel-Aviv, Israel
| | - Michal Werbner
- Azrieli Faculty of Medicine, Bar Ilan University, Safed, Israel
| | - Joel Alter
- Azrieli Faculty of Medicine, Bar Ilan University, Safed, Israel
| | - Modi Safra
- Alexander Kofkin Faculty of Engineering, Bar Ilan University, Ramat Gan, Israel
| | - Elad Chomsky
- ImmunAi, New York, New York, United States of America
| | - Jamie C. Lee
- School of Medicine, University of California San Diego, La Jolla, California, United States of America
| | - Smadar Hada-Neeman
- George S. Wise Life sciences Faculty, Tel Aviv University, Tel-Aviv, Israel
| | - Ksenia Polonsky
- Sackler Faculty of Medicine, Tel Aviv University, Tel-Aviv, Israel
| | - Cameron J. Nowell
- Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia
| | - Alex E. Clark
- School of Medicine, University of California San Diego, La Jolla, California, United States of America
| | | | - Noam Ben-Shalom
- Sackler Faculty of Medicine, Tel Aviv University, Tel-Aviv, Israel
| | - Michal Navon
- Sackler Faculty of Medicine, Tel Aviv University, Tel-Aviv, Israel
| | - Dor Rafael
- Sackler Faculty of Medicine, Tel Aviv University, Tel-Aviv, Israel
| | - Hila Sharim
- ImmunAi, New York, New York, United States of America
| | - Evgeny Kiner
- ImmunAi, New York, New York, United States of America
| | - Eric R. Griffis
- Nikon Imaging Center, University of California San Diego, California, United States of America
| | | | - Oren Kobiler
- Sackler Faculty of Medicine, Tel Aviv University, Tel-Aviv, Israel
| | - Sandra Lawrynowicz Leibel
- School of Medicine, University of California San Diego, La Jolla, California, United States of America
| | | | - Aaron F. Carlin
- School of Medicine, University of California San Diego, La Jolla, California, United States of America
| | - Gur Yaari
- Alexander Kofkin Faculty of Engineering, Bar Ilan University, Ramat Gan, Israel
| | - Moshe Dessau
- Azrieli Faculty of Medicine, Bar Ilan University, Safed, Israel
| | | | | | - Ben A. Croker
- School of Medicine, University of California San Diego, La Jolla, California, United States of America
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5
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Mor M, Werbner M, Alter J, Safra M, Chomsky E, Hada-Neeman S, Polonsky K, Nowell CJ, Clark AE, Roitburd-Berman A, Shalom NB, Navon M, Rafael D, Sharim H, Kiner E, Griffis E, Gershoni JM, Kobiler O, Leibel SL, Zimhony O, Carlin AF, Yaari G, Dassau M, Gal-Tanamy M, Hagin D, Croker BA, Freund NT. Multi-Clonal Live SARS-CoV-2 In Vitro Neutralization by Antibodies Isolated from Severe COVID-19 Convalescent Donors. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.10.06.323634. [PMID: 33052341 PMCID: PMC7553166 DOI: 10.1101/2020.10.06.323634] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The interactions between antibodies, SARS-CoV-2 and immune cells contribute to the pathogenesis of COVID-19 and protective immunity. To understand the differences between antibody responses in mild versus severe cases of COVID-19, we analyzed the B cell responses in patients 1.5 months post SARS-CoV-2 infection. Severe and not mild infection correlated with high titers of IgG against Spike receptor binding domain (RBD) that were capable of viral inhibition. B cell receptor (BCR) sequencing revealed two VH genes, VH3-38 and VH3-53, that were enriched during severe infection. Of the 22 antibodies cloned from two severe donors, six exhibited potent neutralization against live SARS-CoV-2, and inhibited syncytia formation. Using peptide libraries, competition ELISA and RBD mutagenesis, we mapped the epitopes of the neutralizing antibodies (nAbs) to three different sites on the Spike. Finally, we used combinations of nAbs targeting different immune-sites to efficiently block SARS-CoV-2 infection. Analysis of 49 healthy BCR repertoires revealed that the nAbs germline VHJH precursors comprise up to 2.7% of all VHJHs. We demonstrate that severe COVID-19 is associated with unique BCR signatures and multi-clonal neutralizing responses that are relatively frequent in the population. Moreover, our data support the use of combination antibody therapy to prevent and treat COVID-19.
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Affiliation(s)
- Michael Mor
- Department for Microbiology and Clinical Immunology, Faculty of Medicine, Tel Aviv University, Israel
| | - Michal Werbner
- Azrieli Faculty of Medicine, Bar Ilan University, 2800123, Israel
| | - Joel Alter
- Azrieli Faculty of Medicine, Bar Ilan University, 2800123, Israel
| | - Modi Safra
- Faculty of Engineering, Bar Ilan University, 5290002, Israel
| | | | - Smadar Hada-Neeman
- George S Weiss, Life sciences Faculty, Tel Aviv University, 699780, Israel
| | - Ksenia Polonsky
- Department for Microbiology and Clinical Immunology, Faculty of Medicine, Tel Aviv University, Israel
| | - Cameron J Nowell
- Monash Institute of Pharmaceutical Sciences, Parkville, Victoria 3052, Australia
| | - Alex E Clark
- Department of Cellular and Molecular Medicine, School of Medicine, UC San Diego, La Jolla, CA 92093 USA
| | | | - Noam Ben Shalom
- Department for Microbiology and Clinical Immunology, Faculty of Medicine, Tel Aviv University, Israel
| | - Michal Navon
- Department for Microbiology and Clinical Immunology, Faculty of Medicine, Tel Aviv University, Israel
| | - Dor Rafael
- Department for Microbiology and Clinical Immunology, Faculty of Medicine, Tel Aviv University, Israel
| | | | | | - Eric Griffis
- Nikon Imaging Center, UC San Diego, CA, 92093 USA
| | | | - Oren Kobiler
- Department for Microbiology and Clinical Immunology, Faculty of Medicine, Tel Aviv University, Israel
| | | | - Oren Zimhony
- Infectious Diseases unit, Kaplan Medical Center, Rehovot, 7610001, affiliated to the School of Medicine Hebrew University and Hadassah, Israel
| | - Aaron F Carlin
- Department of Cellular and Molecular Medicine, School of Medicine, UC San Diego, La Jolla, CA 92093 USA
| | - Gur Yaari
- Faculty of Engineering, Bar Ilan University, 5290002, Israel
| | - Moshe Dassau
- Azrieli Faculty of Medicine, Bar Ilan University, 2800123, Israel
| | | | - David Hagin
- Department of Immunology Ichilov Hospital, 623906, Israel
| | - Ben A Croker
- Department of Pediatrics, School of Medicine, UC San Diego, La Jolla, CA 92093 USA
| | - Natalia T Freund
- Department for Microbiology and Clinical Immunology, Faculty of Medicine, Tel Aviv University, Israel
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6
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Newman MR, Benoit DSW. In Vivo Translation of Peptide-Targeted Drug Delivery Systems Discovered by Phage Display. Bioconjug Chem 2018; 29:2161-2169. [PMID: 29889510 DOI: 10.1021/acs.bioconjchem.8b00285] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Therapeutic compounds with narrow therapeutic windows and significant systemic side effects benefit from targeted drug delivery strategies. Peptide-protein interactions are often exploited for targeting, with phage display a primary method to identify high-affinity peptide ligands that bind cell surface and matrix bound receptors preferentially expressed in target tissues. After isolating and sequencing high-binding phages, peptides are easily synthesized and chemically modified for incorporation into drug delivery systems, including peptide-drug conjugates, polymers, and nanoparticles. This review describes the phage display methodology to identify targeting peptide sequences, strategies to functionalize drug carriers with phage-derived peptides, specific examples of drug carriers with in vivo translation, and limitations and future applications of phage display to drug delivery.
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Affiliation(s)
- Maureen R Newman
- Center for Musculoskeletal Research, Department of Orthopaedics , University of Rochester Medical Center , Rochester , New York 14642 , United States
| | - Danielle S W Benoit
- Center for Musculoskeletal Research, Department of Orthopaedics , University of Rochester Medical Center , Rochester , New York 14642 , United States
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7
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Ryvkin A, Ashkenazy H, Weiss-Ottolenghi Y, Piller C, Pupko T, Gershoni JM. Phage display peptide libraries: deviations from randomness and correctives. Nucleic Acids Res 2018; 46:e52. [PMID: 29420788 PMCID: PMC5961013 DOI: 10.1093/nar/gky077] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 12/25/2017] [Accepted: 01/31/2018] [Indexed: 12/14/2022] Open
Abstract
Peptide-expressing phage display libraries are widely used for the interrogation of antibodies. Affinity selected peptides are then analyzed to discover epitope mimetics, or are subjected to computational algorithms for epitope prediction. A critical assumption for these applications is the random representation of amino acids in the initial naïve peptide library. In a previous study, we implemented next generation sequencing to evaluate a naïve library and discovered severe deviations from randomness in UAG codon over-representation as well as in high G phosphoramidite abundance causing amino acid distribution biases. In this study, we demonstrate that the UAG over-representation can be attributed to the burden imposed on the phage upon the assembly of the recombinant Protein 8 subunits. This was corrected by constructing the libraries using supE44-containing bacteria which suppress the UAG driven abortive termination. We also demonstrate that the overabundance of G stems from variant synthesis-efficiency and can be corrected using compensating oligonucleotide-mixtures calibrated by mass spectroscopy. Construction of libraries implementing these correctives results in markedly improved libraries that display random distribution of amino acids, thus ensuring that enriched peptides obtained in biopanning represent a genuine selection event, a fundamental assumption for phage display applications.
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Affiliation(s)
- Arie Ryvkin
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Haim Ashkenazy
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Yael Weiss-Ottolenghi
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Chen Piller
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Tal Pupko
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Jonathan M Gershoni
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
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8
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Streptococcus pneumoniae Cell-Wall-Localized Phosphoenolpyruvate Protein Phosphotransferase Can Function as an Adhesin: Identification of Its Host Target Molecules and Evaluation of Its Potential as a Vaccine. PLoS One 2016; 11:e0150320. [PMID: 26990554 PMCID: PMC4798226 DOI: 10.1371/journal.pone.0150320] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Accepted: 02/11/2016] [Indexed: 11/23/2022] Open
Abstract
In Streptococcus pneumonia, phosphoenolpyruvate protein phosphotransferase (PtsA) is an intracellular protein of the monosaccharide phosphotransferase systems. Biochemical and immunostaining methods were applied to show that PtsA also localizes to the bacterial cell-wall. Thus, it was suspected that PtsA has functions other than its main cytoplasmic enzymatic role. Indeed, recombinant PtsA and anti-rPtsA antiserum were shown to inhibit adhesion of S. pneumoniae to cultured human lung adenocarcinoma A549 cells. Screening of a combinatorial peptide library expressed in a filamentous phage with rPtsA identified epitopes that were capable of inhibiting S. pneumoniae adhesion to A549 cells. The insert peptides in the phages were sequenced, and homologous sequences were found in human BMPER, multimerin1, protocadherin19, integrinβ4, epsin1 and collagen type VIIα1 proteins, all of which can be found in A549 cells except the latter. Six peptides, synthesized according to the homologous sequences in the human proteins, specifically bound rPtsA in the micromolar range and significantly inhibited pneumococcal adhesion in vitro to lung- and tracheal-derived cell lines. In addition, the tested peptides inhibited lung colonization after intranasal inoculation of mice with S. pneumoniae. Immunization with rPtsA protected the mice against a sublethal intranasal and a lethal intravenous pneumococcal challenge. In addition, mouse anti rPtsA antiserum reduced bacterial virulence in the intravenous inoculation mouse model. These findings showed that the surface-localized PtsA functions as an adhesin, PtsA binding peptides derived from its putative target molecules can be considered for future development of therapeutics, and rPtsA should be regarded as a candidate for vaccine development.
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Lin X, Chen S, Xue X, Lu L, Zhu S, Li W, Chen X, Zhong X, Jiang P, Sename TS, Zheng Y, Zhang L. Chimerically fused antigen rich of overlapped epitopes from latent membrane protein 2 (LMP2) of Epstein-Barr virus as a potential vaccine and diagnostic agent. Cell Mol Immunol 2015; 13:492-501. [PMID: 25864917 DOI: 10.1038/cmi.2015.29] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 03/05/2015] [Accepted: 03/06/2015] [Indexed: 12/12/2022] Open
Abstract
Epstein-Barr virus (EBV) is prevalent throughout the world and is associated with several malignant diseases in humans. Latent membrane protein 2 (LMP2) of EBV plays a crucial role in the pathogenesis of EBV-associated tumors; therefore, LMP2 has been considered to be a potential immunodiagnostic and immunotherapeutic target. A multi-epitope-based antigen is a promising option for therapeutic vaccines and diagnoses of such malignancies. In this study, we systematically screened cytotoxic T lymphocyte (CTL), helper T cell (Th) and B-cell epitopes within EBV-LMP2 using bioinformatics. Based on the screen, two peptides rich in overlapping epitopes of both T cells and B cells were selected to construct a plasmid containing the sequence for a chimeric multi-epitope protein referred to as EBV-LMP2m, which is composed of LMP2aa195∼232 and LMP2aa419∼436. The EBV-LMP2m protein was expressed in E. coli BL21 (DE3) after prokaryotic codon optimization. Inoculation of the purified chimeric antigen in BALB/c mice induced not only high levels of specific IgG in the serum and secretory IgA in the vaginal mucus but also a specific CTL response. By using purified EBV-LMP2m as an antigen, the presence of specific IgG in the serum specimens of 202 nasopharyngeal carcinoma (NPC) patients was effectively detected with 52.84% sensitivity and 95.40% specificity, which represents an improvement over the traditional detection method based on VCA-IgA (60.53% sensitivity and 76.86% specificity). The above results indicate that EBV-LMP2m may be used not only as a potential target antigen for EBV-associated tumors but also a diagnostic agent for NPC patients.
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Affiliation(s)
- Xiaoyun Lin
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
| | - Shao Chen
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
| | - Xiangyang Xue
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
| | - Lijun Lu
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
| | - Shanli Zhu
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
| | - Wenshu Li
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
| | - Xiangmin Chen
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
| | - Xiaozhi Zhong
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
| | - Pengfei Jiang
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
| | - Torsoo Sophia Sename
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
| | - Yi Zheng
- School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, China
| | - Lifang Zhang
- Department of Microbiology and Immunology, Institute of Molecular Virology and Immunology, Wenzhou Medical University, Wenzhou, China
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Ebrahimizadeh W, Rajabibazl M. Bacteriophage vehicles for phage display: biology, mechanism, and application. Curr Microbiol 2014; 69:109-20. [PMID: 24638925 DOI: 10.1007/s00284-014-0557-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 01/26/2014] [Indexed: 11/29/2022]
Abstract
The phage display technique is a powerful tool for selection of various biological agents. This technique allows construction of large libraries from the antibody repertoire of different hosts and provides a fast and high-throughput selection method. Specific antibodies can be isolated based on distinctive characteristics from a library consisting of millions of members. These features made phage display technology preferred method for antibody selection and engineering. There are several phage display methods available and each has its unique merits and application. Selection of appropriate display technique requires basic knowledge of available methods and their mechanism. In this review, we describe different phage display techniques, available bacteriophage vehicles, and their mechanism.
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Affiliation(s)
- Walead Ebrahimizadeh
- Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran,
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11
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Weiss-Ottolenghi Y, Gershoni JM. Profiling the IgOme: meeting the challenge. FEBS Lett 2014; 588:318-25. [PMID: 24239539 PMCID: PMC7094557 DOI: 10.1016/j.febslet.2013.11.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 11/06/2013] [Accepted: 11/06/2013] [Indexed: 02/03/2023]
Abstract
The entire repertoire of antibodies in our serum, the IgOme, is a historical record of our past experiences and a reflection of our immune status at any given moment. Understanding the dynamics of the IgOme and how the diversity and specificities of serum antibodies change in response to disease and maintenance of homeostasis can directly impact the ability to design and develop novel vaccines, diagnostics and therapeutics. Here we review both direct and indirect methodologies that are being developed to map the complexity and specificities of the antibodies in polyclonal serum - the IgOme.
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Affiliation(s)
- Yael Weiss-Ottolenghi
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Jonathan M Gershoni
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel.
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12
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Roitburd-Berman A, Dela G, Kaplan G, Lewis GK, Gershoni JM. Allosteric induction of the CD4-bound conformation of HIV-1 Gp120. Retrovirology 2013; 10:147. [PMID: 24304511 PMCID: PMC4235218 DOI: 10.1186/1742-4690-10-147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 11/25/2013] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND HIV-1 infection of target cells is mediated via the binding of the viral envelope protein, gp120, to the cell surface receptor CD4. This interaction leads to conformational rearrangements in gp120 forming or revealing CD4 induced (CD4i) epitopes which are critical for the subsequent recognition of the co-receptor required for viral entry. The CD4-bound state of gp120 has been considered a potential immunogen for HIV-1 vaccine development. Here we report on an alternative means to induce gp120 into the CD4i conformation. RESULTS Combinatorial phage display peptide libraries were screened against HIV-1 gp120 and short (14aa) peptides were selected that bind the viral envelope and allosterically induce the CD4i conformation. The lead peptide was subsequently systematically optimized for higher affinity as well as more efficient inductive activity. The peptide:gp120 complex was scrutinized with a panel of neutralizing anti-gp120 monoclonal antibodies and CD4 itself, illustrating that peptide binding does not interfere with or obscure the CD4 binding site. CONCLUSIONS Two surfaces of gp120 are considered targets for the development of cross neutralizing antibodies against HIV-1; the CD4 binding site and CD4i epitopes. By implementing novel peptides that allosterically induce the CD4i epitopes we have generated a viral envelope that presents both of these surfaces simultaneously.
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Affiliation(s)
| | | | | | | | - Jonathan M Gershoni
- Department of Cell Research and Immunology, George S, Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
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13
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Muchnik L, Adawi A, Ohayon A, Dotan S, Malka I, Azriel S, Shagan M, Portnoi M, Kafka D, Nahmani H, Porgador A, Gershoni JM, Gershoni JM, Morrison DA, Mitchell A, Tal M, Ellis R, Dagan R, Nebenzahl YM. NADH oxidase functions as an adhesin in Streptococcus pneumoniae and elicits a protective immune response in mice. PLoS One 2013; 8:e61128. [PMID: 23577197 PMCID: PMC3620118 DOI: 10.1371/journal.pone.0061128] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 03/08/2013] [Indexed: 11/18/2022] Open
Abstract
The initial event in disease caused by S. pneumoniae is adhesion of the bacterium to respiratory epithelial cells, mediated by surface expressed molecules including cell-wall proteins. NADH oxidase (NOX), which reduces free oxygen to water in the cytoplasm, was identified in a non-lectin enriched pneumococcal cell-wall fraction. Recombinant NOX (rNOX) was screened with sera obtained longitudinally from children and demonstrated age-dependent immunogenicity. NOX ablation in S. pneumoniae significantly reduced bacterial adhesion to A549 epithelial cells in vitro and their virulence in the intranasal or intraperitoneal challenge models in mice, compared to the parental strain. Supplementation of Δnox WU2 with the nox gene restored its virulence. Saturation of A549 target cells with rNOX or neutralization of cell-wall residing NOX using anti-rNOX antiserum decreased adhesion to A549 cells. rNOX-binding phages inhibited bacterial adhesion. Moreover, peptides derived from the human proteins contactin 4, chondroitin 4 sulfotraferase and laminin5, homologous to the insert peptides in the neutralizing phages, inhibited bacterial adhesion to the A549 cells. Furthermore, rNOX immunization of mice elicited a protective immune response to intranasal or intraperitoneal S. pneumoniae challenge, whereas pneumococcal virulence was neutralized by anti-rNOX antiserum prior to intraperitoneal challenge. Our results suggest that in addition to its enzymatic activity, NOX contributes to S. pneumoniae virulence as a putative adhesin and thus peptides derived from its target molecules may be considered for the treatment of pneumococcal infections. Finally, rNOX elicited a protective immune response in both aerobic and anaerobic environments, which renders NOX a candidate for future pneumococcal vaccine.
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Affiliation(s)
- Lena Muchnik
- Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer Sheva, Israel
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14
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Siman-Tov DD, Zemel R, Tur Kaspa R, Gershoni JM. The use of epitope arrays in immunodiagnosis of infectious disease: hepatitis C virus, a case study. Anal Biochem 2012; 432:63-70. [PMID: 23017878 DOI: 10.1016/j.ab.2012.09.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Revised: 09/16/2012] [Accepted: 09/17/2012] [Indexed: 01/23/2023]
Abstract
Serodiagnosis of infectious disease is often based on the detection of pathogen-specific antibodies in a patient's blood. For this, mixtures of pathogen-related antigens are used as bait to capture corresponding antibodies in solid phase immunoassays such as enzyme immunoassay (EIA). Western blots provide improved diagnostic power as compared with EIA due to the fact that the mixture of markers in the EIA well is resolved and tested as individual antigens on the Western blot. Hence, confirmation of EIA results is accomplished using the antigen arrays of Western blots. Here we took this approach one step further and tested the attributes of using epitope arrays in a diagnostic platform coined "combinatorial diagnostics." As a case in point, we tested a panel of phage-displayed epitope-based markers in the serodiagnosis of hepatitis C virus (HCV). The repertoire of HCV antigens was deconvoluted into panels of distinct linear and conformational epitopes and tested individually by quantitative EIA. Combinatorial diagnostics proved to be effective for the discrimination between positive and negative sera as well as serotyping of HCV.
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Affiliation(s)
- Dror D Siman-Tov
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv 69978, Israel
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15
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Ryvkin A, Ashkenazy H, Smelyanski L, Kaplan G, Penn O, Weiss-Ottolenghi Y, Privman E, Ngam PB, Woodward JE, May GD, Bell C, Pupko T, Gershoni JM. Deep Panning: steps towards probing the IgOme. PLoS One 2012; 7:e41469. [PMID: 22870226 PMCID: PMC3409857 DOI: 10.1371/journal.pone.0041469] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 06/21/2012] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Polyclonal serum consists of vast collections of antibodies, products of differentiated B-cells. The spectrum of antibody specificities is dynamic and varies with age, physiology, and exposure to pathological insults. The complete repertoire of antibody specificities in blood, the IgOme, is therefore an extraordinarily rich source of information-a molecular record of previous encounters as well as a status report of current immune activity. The ability to profile antibody specificities of polyclonal serum at exceptionally high resolution has been an important and serious challenge which can now be overcome. METHODOLOGY/PRINCIPAL FINDINGS Here we illustrate the application of Deep Panning, a method that combines the flexibility of combinatorial phage display of random peptides with the power of high-throughput deep sequencing. Deep Panning is first applied to evaluate the quality and diversity of naïve random peptide libraries. The production of very large data sets, hundreds of thousands of peptides, has revealed unexpected properties of combinatorial random peptide libraries and indicates correctives to ensure the quality of the libraries generated. Next, Deep Panning is used to analyze a model monoclonal antibody in addition to allowing one to follow the dynamics of biopanning and peptide selection. Finally Deep Panning is applied to profile polyclonal sera derived from HIV infected individuals. CONCLUSIONS/SIGNIFICANCE The ability to generate and characterize hundreds of thousands of affinity-selected peptides creates an effective means towards the interrogation of the IgOme and understanding of the humoral response to disease. Deep Panning should open the door to new possibilities for serological diagnostics, vaccine design and the discovery of the correlates of immunity to emerging infectious agents.
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Affiliation(s)
- Arie Ryvkin
- Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel
| | - Haim Ashkenazy
- Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel
| | - Larisa Smelyanski
- Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel
| | - Gilad Kaplan
- Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel
| | - Osnat Penn
- Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel
| | | | - Eyal Privman
- Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel
| | - Peter B. Ngam
- National Center for Genome Resources, Santa Fe, New Mexico, United States of America
| | - James E. Woodward
- National Center for Genome Resources, Santa Fe, New Mexico, United States of America
| | - Gregory D. May
- National Center for Genome Resources, Santa Fe, New Mexico, United States of America
| | - Callum Bell
- National Center for Genome Resources, Santa Fe, New Mexico, United States of America
| | - Tal Pupko
- Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel
| | - Jonathan M. Gershoni
- Department of Cell Research and Immunology, Tel Aviv University, Tel Aviv, Israel
- * E-mail:
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A human PrM antibody that recognizes a novel cryptic epitope on dengue E glycoprotein. PLoS One 2012; 7:e33451. [PMID: 22509258 PMCID: PMC3317930 DOI: 10.1371/journal.pone.0033451] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 02/14/2012] [Indexed: 01/01/2023] Open
Abstract
Dengue virus (DENV) is a major mosquito-borne pathogen infecting up to 100 million people each year; so far no effective treatment or vaccines are available. Recently, highly cross-reactive and infection-enhancing pre-membrane (prM)-specific antibodies were found to dominate the anti-DENV immune response in humans, raising concern over vaccine candidates that contain native dengue prM sequences. In this study, we have isolated a broadly cross-reactive prM-specific antibody, D29, during a screen with a non-immunized human Fab-phage library against the four serotypes of DENV. The antibody is capable of restoring the infectivity of virtually non-infectious immature DENV (imDENV) in FcγR-bearing K562 cells. Remarkably, D29 also cross-reacted with a cryptic epitope on the envelope (E) protein located to the DI/DII junction as evidenced by site-directed mutagenesis. This cryptic epitope, while inaccessible to antibody binding in a native virus particle, may become exposed if E is not properly folded. These findings suggest that generation of anti-prM antibodies that enhance DENV infection may not be completely avoided even with immunization strategies employing E protein alone or subunits of E proteins.
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17
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Smelyanski L, Gershoni JM. Site directed biotinylation of filamentous phage structural proteins. Virol J 2011; 8:495. [PMID: 22044460 PMCID: PMC3256129 DOI: 10.1186/1743-422x-8-495] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2011] [Accepted: 11/01/2011] [Indexed: 11/17/2022] Open
Abstract
Filamentous bacteriophages have been used in numerous applications for the display of antibodies and random peptide libraries. Here we describe the introduction of a 13 amino acid sequence LASIFEAQKIEWR (designated BT, which is biotinylated in vivo by E. coli) into the N termini of four of the five structural proteins of the filamentous bacteriophage fd (Proteins 3, 7, 8 and 9). The in vivo and in vitro biotinylation of the various phages were compared. The production of multifunctional phages and their application as affinity reagents are demonstrated.
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Affiliation(s)
- Larisa Smelyanski
- Department of Cell Research and Immunology, George S, Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 69978 Israel
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Abstract
Here, we discuss various questions related to IgE epitopes: What are the technical possibilities and pitfalls, what is currently known, how can we put this information into hypothetical frameworks and the unavoidable question: how useful is this information for patient care or allergenicity prediction? We discuss the information obtained by (i) 3D structures of allergen-antibody complexes; (ii) analysis of allergen analogues; (iii) mimics without obvious structural similarity; (iv) mAbs competing with IgE; (v) repertoire analysis of cloned IgEs, and other developments. Based on limited data, four suggestions are presented in the literature: (i) IgE might be more cross-reactive than IgG; (ii) IgE might be more often directed to immunologically 'uninviting' surfaces; (iii) IgE epitopes may tend to cluster and (iv) IgE paratopes might have a higher intrinsic flexibility. While these are not proven facts, they still can generate hypotheses for future research. The hypothesis is put forward that the IgE repertoire of switched B-cells is less influenced by positive selection, because positive selection might not be able to rescue IgE-switched B cells. While this might be of interest for the discussion about mechanisms leading to allergen-sensitization, we need to be modest in answering the 'clinical relevance' question. Current evidence indicates the IgE-epitope repertoire is too big to make specific IgE epitopes a realistic target for diagnosis, treatment or allergenicity prediction. In-depth analysis of a few selected IgE epitope-peptides or mimitopes derived from allergen-sequences and from random peptide libraries, respectively, might well prove rewarding in relation to diagnosis and prognosis of allergy, particularly food allergy.
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Affiliation(s)
- R C Aalberse
- Department of Immunopathology, Sanquin Research and Academic Medical Centre, Amsterdam, the Netherlands.
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19
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Kaplan G, Gershoni JM. A general insert label for peptide display on chimeric filamentous bacteriophages. Anal Biochem 2011; 420:68-72. [PMID: 21945353 PMCID: PMC7094602 DOI: 10.1016/j.ab.2011.08.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2011] [Revised: 08/29/2011] [Accepted: 08/30/2011] [Indexed: 12/12/2022]
Abstract
The foreign insert intended to be displayed via recombinant phage proteins can have a negative effect on protein expression and phage assembly. A typical example is the case of display of peptides longer than 6 amino acid residues on the major coat protein, protein VIII of the filamentous bacteriophages M13 and fd. A solution to this problem has been the use of “two-gene systems” generating chimeric phages that concomitantly express wild-type protein VIII along with recombinant protein VIII. Although the two-gene systems are much more permissive in regard to insert length and composition, some cases can still adversely affect phage assembly. Although these phages genotypically contain the desired DNA of the insert, they appear to be phenotypically wild type. To avoid false-negative results when using chimeric phages in binding studies, it is necessary to confirm that the observed lack of phage recognition is not due to faulty assembly and display of the intended insert. Here we describe a strategy for generating antibodies that specifically recognize recombinant protein VIII regardless of the nature of its foreign insert. These antibodies can be used as a general monitor of the display of recombinant protein VIII into phage particles.
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Affiliation(s)
- Gilad Kaplan
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
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20
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Sedegah M, Kim Y, Peters B, McGrath S, Ganeshan H, Lejano J, Abot E, Banania G, Belmonte M, Sayo R, Farooq F, Doolan DL, Regis D, Tamminga C, Chuang I, Bruder JT, King CR, Ockenhouse CF, Faber B, Remarque E, Hollingdale MR, Richie TL, Sette A. Identification and localization of minimal MHC-restricted CD8+ T cell epitopes within the Plasmodium falciparum AMA1 protein. Malar J 2010; 9:241. [PMID: 20735847 PMCID: PMC2939619 DOI: 10.1186/1475-2875-9-241] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Accepted: 08/24/2010] [Indexed: 12/14/2022] Open
Abstract
Background Plasmodium falciparum apical membrane antigen-1 (AMA1) is a leading malaria vaccine candidate antigen that is expressed by sporozoite, liver and blood stage parasites. Since CD8+ T cell responses have been implicated in protection against pre-erythrocytic stage malaria, this study was designed to identify MHC class I-restricted epitopes within AMA1. Methods A recombinant adenovirus serotype 5 vector expressing P. falciparum AMA1 was highly immunogenic when administered to healthy, malaria-naive adult volunteers as determined by IFN-γ ELISpot responses to peptide pools containing overlapping 15-mer peptides spanning full-length AMA1. Computerized algorithms (NetMHC software) were used to predict minimal MHC-restricted 8-10-mer epitope sequences within AMA1 15-mer peptides active in ELISpot. A subset of epitopes was synthesized and tested for induction of CD8+ T cell IFN-γ responses by ELISpot depletion and ICS assays. A 3-dimensional model combining Domains I + II of P. falciparum AMA1 and Domain III of P. vivax AMA1 was used to map these epitopes. Results Fourteen 8-10-mer epitopes were predicted to bind to HLA supertypes A01 (3 epitopes), A02 (4 epitopes), B08 (2 epitopes) and B44 (5 epitopes). Nine of the 14 predicted epitopes were recognized in ELISpot or ELISpot and ICS assays by one or more volunteers. Depletion of T cell subsets confirmed that these epitopes were CD8+ T cell-dependent. A mixture of the 14 minimal epitopes was capable of recalling CD8+ T cell IFN-γ responses from PBMC of immunized volunteers. Thirteen of the 14 predicted epitopes were polymorphic and the majority localized to the more conserved front surface of the AMA1 model structure. Conclusions This study predicted 14 and confirmed nine MHC class I-restricted CD8+ T cell epitopes on AMA1 recognized in the context of seven HLA alleles. These HLA alleles belong to four HLA supertypes that have a phenotypic frequency between 23% - 100% in different human populations.
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Affiliation(s)
- Martha Sedegah
- USMMVP, Malaria Department, NMRC, Silver Spring, MD 20910, USA
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