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  1. AU="Zang, Trinity"
  2. AU="Almayahi, Basim A"
  3. AU="Lupke, Madeleine"
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  1. Article ; Online: Initiation of HIV-1 Gag lattice assembly is required for recognition of the viral genome packaging signal.

    Lei, Xiao / Gonçalves-Carneiro, Daniel / Zang, Trinity M / Bieniasz, Paul D

    eLife

    2023  Volume 12

    Abstract: The encapsidation of HIV-1 gRNA into virions is enabled by the binding of the nucleocapsid (NC) domain of the HIV-1 Gag polyprotein to the structured viral RNA packaging signal (Ψ) at the 5' end of the viral genome. However, the subcellular location and ... ...

    Abstract The encapsidation of HIV-1 gRNA into virions is enabled by the binding of the nucleocapsid (NC) domain of the HIV-1 Gag polyprotein to the structured viral RNA packaging signal (Ψ) at the 5' end of the viral genome. However, the subcellular location and oligomeric status of Gag during the initial Gag-Ψ encounter remain uncertain. Domains other than NC, such as capsid (CA), may therefore indirectly affect RNA recognition. To investigate the contribution of Gag domains to Ψ recognition in a cellular environment, we performed protein-protein crosslinking and protein-RNA crosslinking immunoprecipitation coupled with sequencing (CLIP-seq) experiments. We demonstrate that NC alone does not bind specifically to Ψ in living cells, whereas full-length Gag and a CANC subdomain bind to Ψ with high specificity. Perturbation of the Ψ RNA structure or NC zinc fingers affected CANC:Ψ binding specificity. Notably, CANC variants with substitutions that disrupt CA:CA dimer, trimer, or hexamer interfaces in the immature Gag lattice also affected RNA binding, and mutants that were unable to assemble a nascent Gag lattice were unable to specifically bind to Ψ. Artificially multimerized NC domains did not specifically bind Ψ. CA variants with substitutions in inositol phosphate coordinating residues that prevent CA hexamerization were also deficient in Ψ binding and second-site revertant mutants that restored CA assembly also restored specific binding to Ψ. Overall, these data indicate that the correct assembly of a nascent immature CA lattice is required for the specific interaction between Gag and Ψ in cells.
    MeSH term(s) Viral Genome Packaging ; RNA, Viral/genetics ; HIV-1/genetics ; Virus Assembly/genetics ; Nucleocapsid/metabolism ; Capsid Proteins/metabolism ; Genome, Viral
    Chemical Substances RNA, Viral ; Capsid Proteins
    Language English
    Publishing date 2023-01-23
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.83548
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Derivation and characterization of an HIV-1 mutant that rescues IP

    Poston, Daniel / Zang, Trinity / Bieniasz, Paul

    Retrovirology

    2021  Volume 18, Issue 1, Page(s) 25

    Abstract: Background: A critical step in the HIV-1 replication cycle is the assembly of Gag proteins to form virions at the plasma membrane. Virion assembly and maturation are facilitated by the cellular polyanion inositol hexaphosphate (IP: Results: We found ... ...

    Abstract Background: A critical step in the HIV-1 replication cycle is the assembly of Gag proteins to form virions at the plasma membrane. Virion assembly and maturation are facilitated by the cellular polyanion inositol hexaphosphate (IP
    Results: We found a mutation, a threonine to isoleucine substitution at position 371 (T371I) in Gag, that restored replication competence to an IP
    Conclusions: Overall these results suggest that IP
    MeSH term(s) Amino Acid Substitution ; Capsid Proteins/metabolism ; HEK293 Cells ; HIV-1/genetics ; HIV-1/metabolism ; Humans ; Mutation ; Phytic Acid/metabolism ; Virion/metabolism ; Virus Assembly ; gag Gene Products, Human Immunodeficiency Virus/metabolism
    Chemical Substances Capsid Proteins ; gag Gene Products, Human Immunodeficiency Virus ; Phytic Acid (7IGF0S7R8I)
    Language English
    Publishing date 2021-08-28
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2142602-8
    ISSN 1742-4690 ; 1742-4690
    ISSN (online) 1742-4690
    ISSN 1742-4690
    DOI 10.1186/s12977-021-00571-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Heteromultimeric sarbecovirus receptor binding domain immunogens primarily generate variant-specific neutralizing antibodies.

    Zang, Trinity / Osei Kuffour, Edmund / Baharani, Viren A / Canis, Marie / Schmidt, Fabian / Da Silva, Justin / Lercher, Alexander / Chaudhary, Pooja / Hoffmann, Hans-Heinrich / Gazumyan, Anna / Miranda, Ileana C / MacDonald, Margaret R / Rice, Charles M / Nussenzweig, Michel C / Hatziioannou, Theodora / Bieniasz, Paul D

    Proceedings of the National Academy of Sciences of the United States of America

    2023  Volume 120, Issue 51, Page(s) e2317367120

    Abstract: Vaccination will likely be a key component of strategies to curtail or prevent future sarbecovirus pandemics and to reduce the prevalence of infection and disease by future SARS-CoV-2 variants. A "pan-sarbecovirus" vaccine, that provides maximum possible ...

    Abstract Vaccination will likely be a key component of strategies to curtail or prevent future sarbecovirus pandemics and to reduce the prevalence of infection and disease by future SARS-CoV-2 variants. A "pan-sarbecovirus" vaccine, that provides maximum possible mitigation of human disease, should elicit neutralizing antibodies with maximum possible breadth. By positioning multiple different receptor binding domain (RBD) antigens in close proximity on a single immunogen, it is postulated that cross-reactive B cell receptors might be selectively engaged. Heteromultimeric vaccines could therefore elicit individual antibodies that neutralize a broad range of viral species. Here, we use model systems to investigate the ability of multimeric sarbecovirus RBD immunogens to expand cross-reactive B cells and elicit broadly reactive antibodies. Homomultimeric RBD immunogens generated higher serum neutralizing antibody titers than the equivalent monomeric immunogens, while heteromultimeric RBD immunogens generated neutralizing antibodies recognizing each RBD component. Moreover, RBD heterodimers elicited a greater fraction of cross-reactive germinal center B cells and cross-reactive RBD binding antibodies than did homodimers. However, when serum antibodies from RBD heterodimer-immunized mice were depleted using one RBD component, neutralization activity against the homologous viral pseudotype was removed, but neutralization activity against pseudotypes corresponding to the other RBD component was unaffected. Overall, simply combining divergent RBDs in a single immunogen generates largely separate sets of individual RBD-specific neutralizing serum antibodies that are mostly incapable of neutralizing viruses that diverge from the immunogen components.
    MeSH term(s) Animals ; Mice ; Humans ; Antibodies, Neutralizing ; Antibodies, Viral ; Neutralization Tests ; Severe acute respiratory syndrome-related coronavirus ; Vaccination ; Spike Glycoprotein, Coronavirus/chemistry
    Chemical Substances Antibodies, Neutralizing ; Antibodies, Viral ; Spike Glycoprotein, Coronavirus
    Language English
    Publishing date 2023-12-14
    Publishing country United States
    Document type Journal Article
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2317367120
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Molecular fate-mapping of serum antibody responses to repeat immunization.

    Schiepers, Ariën / van 't Wout, Marije F L / Greaney, Allison J / Zang, Trinity / Muramatsu, Hiromi / Lin, Paulo J C / Tam, Ying K / Mesin, Luka / Starr, Tyler N / Bieniasz, Paul D / Pardi, Norbert / Bloom, Jesse D / Victora, Gabriel D

    Nature

    2023  Volume 615, Issue 7952, Page(s) 482–489

    Abstract: The protective efficacy of serum antibodies results from the interplay of antigen-specific B cell clones of different affinities and specificities. These cellular dynamics underlie serum-level phenomena such as original antigenic sin (OAS)-a proposed ... ...

    Abstract The protective efficacy of serum antibodies results from the interplay of antigen-specific B cell clones of different affinities and specificities. These cellular dynamics underlie serum-level phenomena such as original antigenic sin (OAS)-a proposed propensity of the immune system to rely repeatedly on the first cohort of B cells engaged by an antigenic stimulus when encountering related antigens, in detriment to the induction of de novo responses
    MeSH term(s) Humans ; Antibodies, Viral/biosynthesis ; Antibodies, Viral/blood ; Antibodies, Viral/immunology ; Antibody Formation ; Antigens, Viral/immunology ; Influenza Vaccines/immunology ; SARS-CoV-2/immunology ; Vaccination ; Immunization, Secondary ; B-Lymphocytes/immunology ; Viral Vaccines/immunology
    Chemical Substances Antibodies, Viral ; Antigens, Viral ; Influenza Vaccines ; Viral Vaccines
    Language English
    Publishing date 2023-01-16
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/s41586-023-05715-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Inhibition of major histocompatibility complex-I antigen presentation by sarbecovirus ORF7a proteins.

    Zhang, Fengwen / Zang, Trinity / Stevenson, Eva M / Lei, Xiao / Copertino, Dennis C / Mota, Talia M / Boucau, Julie / Garcia-Beltran, Wilfredo F / Jones, R Brad / Bieniasz, Paul D

    bioRxiv : the preprint server for biology

    2022  

    Abstract: Viruses employ a variety of strategies to escape or counteract immune responses, including depletion of cell surface major histocompatibility complex class I (MHC-I), that would ordinarily present viral peptides to CD8+ cytotoxic T cells. As part of a ... ...

    Abstract Viruses employ a variety of strategies to escape or counteract immune responses, including depletion of cell surface major histocompatibility complex class I (MHC-I), that would ordinarily present viral peptides to CD8+ cytotoxic T cells. As part of a screen to elucidate biological activities associated with individual SARS-CoV-2 viral proteins, we found that ORF7a reduced cell surface MHC-I levels by approximately 5-fold. Nevertheless, in cells infected with SARS-CoV-2, surface MHC-I levels were reduced even in the absence of ORF7a, suggesting additional mechanisms of MHC-I downregulation. ORF7a proteins from a sample of sarbecoviruses varied in their ability to induce MHC-I downregulation and, unlike SARS-CoV-2, the ORF7a protein from SARS-CoV lacked MHC-I downregulating activity. A single-amino acid at position 59 (T/F) that is variable among sarbecovirus ORF7a proteins governed the difference in MHC-I downregulating activity. SARS-CoV-2 ORF7a physically associated with the MHC-I heavy chain and inhibited the presentation of expressed antigen to CD8+ T-cells. Speficially, ORF7a prevented the assembly of the MHC-I peptide loading complex and causing retention of MHC-I in the endoplasmic reticulum. The differential ability of ORF7a proteins to function in this way might affect sarbecovirus dissemination and persistence in human populations, particularly those with infection- or vaccine-elicited immunity.
    Language English
    Publishing date 2022-05-26
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2022.05.25.493467
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Inhibition of major histocompatibility complex-I antigen presentation by sarbecovirus ORF7a proteins.

    Zhang, Fengwen / Zang, Trinity M / Stevenson, Eva M / Lei, Xiao / Copertino, Dennis C / Mota, Talia M / Boucau, Julie / Garcia-Beltran, Wilfredo F / Jones, R Brad / Bieniasz, Paul D

    Proceedings of the National Academy of Sciences of the United States of America

    2022  Volume 119, Issue 41, Page(s) e2209042119

    Abstract: Viruses employ a variety of strategies to escape or counteract immune responses, including depletion of cell surface major histocompatibility complex class I (MHC-I), that would ordinarily present viral peptides to ... ...

    Abstract Viruses employ a variety of strategies to escape or counteract immune responses, including depletion of cell surface major histocompatibility complex class I (MHC-I), that would ordinarily present viral peptides to CD8
    MeSH term(s) Amino Acids ; Antigen Presentation ; CD8-Positive T-Lymphocytes/immunology ; COVID-19/immunology ; Histocompatibility Antigens Class I/immunology ; Humans ; Major Histocompatibility Complex ; Peptides ; SARS-CoV-2 ; Viral Proteins/immunology
    Chemical Substances Amino Acids ; Histocompatibility Antigens Class I ; ORF7a protein, SARS-CoV-2 ; Peptides ; Viral Proteins
    Language English
    Publishing date 2022-09-22
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2209042119
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Vpu binds directly to tetherin and displaces it from nascent virions.

    McNatt, Matthew W / Zang, Trinity / Bieniasz, Paul D

    PLoS pathogens

    2013  Volume 9, Issue 4, Page(s) e1003299

    Abstract: Tetherin (Bst2/CD317/HM1.24) is an interferon-induced antiviral host protein that inhibits the release of many enveloped viruses by tethering virions to the cell surface. The HIV-1 accessory protein, Vpu, antagonizes Tetherin through a variety of ... ...

    Abstract Tetherin (Bst2/CD317/HM1.24) is an interferon-induced antiviral host protein that inhibits the release of many enveloped viruses by tethering virions to the cell surface. The HIV-1 accessory protein, Vpu, antagonizes Tetherin through a variety of proposed mechanisms, including surface downregulation and degradation. Previous studies have demonstrated that mutation of the transmembrane domains (TMD) of both Vpu and Tetherin affect antagonism, but it is not known whether Vpu and Tetherin bind directly to each other. Here, we use cysteine-scanning mutagenesis coupled with oxidation-induced cross-linking to demonstrate that Vpu and Tetherin TMDs bind directly to each other in the membranes of living cells and to map TMD residues that contact each other. We also reveal a property of Vpu, namely the ability to displace Tetherin from sites of viral assembly, which enables Vpu to exhibit residual Tetherin antagonist activity in the absence of surface downregulation or degradation. Elements in the cytoplasmic tail domain (CTD) of Vpu mediate this displacement activity, as shown by experiments in which Vpu CTD fragments were directly attached to Tetherin in the absence of the TMD. In particular, the C-terminal α-helix (H2) of Vpu CTD is sufficient to remove Tetherin from sites of viral assembly and is necessary for full Tetherin antagonist activity. Overall, these data demonstrate that Vpu and Tetherin interact directly via their transmembrane domains enabling activities present in the CTD of Vpu to remove Tetherin from sites of viral assembly.
    MeSH term(s) Antigens, CD/chemistry ; Antigens, CD/metabolism ; Binding Sites ; Cell Line, Tumor ; Cell Membrane/metabolism ; Down-Regulation ; GPI-Linked Proteins/antagonists & inhibitors ; GPI-Linked Proteins/chemistry ; GPI-Linked Proteins/metabolism ; HEK293 Cells ; HIV Infections/virology ; HIV-1/genetics ; HIV-1/metabolism ; HeLa Cells ; Human Immunodeficiency Virus Proteins/chemistry ; Human Immunodeficiency Virus Proteins/genetics ; Human Immunodeficiency Virus Proteins/metabolism ; Humans ; Membrane Proteins/metabolism ; Protein Binding ; Protein Interaction Domains and Motifs ; Protein Structure, Tertiary ; Viral Regulatory and Accessory Proteins/chemistry ; Viral Regulatory and Accessory Proteins/genetics ; Viral Regulatory and Accessory Proteins/metabolism ; Virus Assembly ; Virus Release
    Chemical Substances Antigens, CD ; BST2 protein, human ; GPI-Linked Proteins ; Human Immunodeficiency Virus Proteins ; Membrane Proteins ; Viral Regulatory and Accessory Proteins ; vpu protein, Human immunodeficiency virus 1
    Language English
    Publishing date 2013-04-25
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2205412-1
    ISSN 1553-7374 ; 1553-7366
    ISSN (online) 1553-7374
    ISSN 1553-7366
    DOI 10.1371/journal.ppat.1003299
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Molecular fate-mapping of serum antibodies reveals the effects of antigenic imprinting on repeated immunization.

    Schiepers, Ariën / van 't Wout, Marije F L / Greaney, Allison J / Zang, Trinity / Muramatsu, Hiromi / Lin, Paulo J C / Tam, Ying K / Mesin, Luka / Starr, Tyler N / Bieniasz, Paul D / Pardi, Norbert / Bloom, Jesse D / Victora, Gabriel D

    bioRxiv : the preprint server for biology

    2022  

    Abstract: The ability of serum antibody to protect against pathogens arises from the interplay of antigen-specific B cell clones of different affinities and fine specificities. These cellular dynamics are ultimately responsible for serum-level phenomena such as ... ...

    Abstract The ability of serum antibody to protect against pathogens arises from the interplay of antigen-specific B cell clones of different affinities and fine specificities. These cellular dynamics are ultimately responsible for serum-level phenomena such as antibody imprinting or "Original Antigenic Sin" (OAS), a proposed propensity of the immune system to rely repeatedly on the first cohort of B cells that responded to a stimulus upon exposure to related antigens. Imprinting/OAS is thought to pose a barrier to vaccination against rapidly evolving viruses such as influenza and SARS-CoV-2. Precise measurement of the extent to which imprinting/OAS inhibits the recruitment of new B cell clones by boosting is challenging because cellular and temporal origins cannot readily be assigned to antibodies in circulation. Thus, the extent to which imprinting/OAS impacts the induction of new responses in various settings remains unclear. To address this, we developed a "molecular fate-mapping" approach in which serum antibodies derived from specific cohorts of B cells can be differentially detected. We show that, upon sequential homologous boosting, the serum antibody response strongly favors reuse of the first cohort of B cell clones over the recruitment of new, naÏve-derived B cells. This "primary addiction" decreases as a function of antigenic distance, allowing secondary immunization with divergent influenza virus or SARS-CoV-2 glycoproteins to overcome imprinting/OAS by targeting novel epitopes absent from the priming variant. Our findings have implications for the understanding of imprinting/OAS, and for the design and testing of vaccines aimed at eliciting antibodies to evolving antigens.
    Language English
    Publishing date 2022-09-06
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2022.08.29.505743
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Inhibition of major histocompatibility complex-I antigen presentation by sarbecovirus ORF7a proteins

    Zhang, Fengwen / Zang, Trinity / Stevenson, Eva M / Lei, Xiao / Copertino, Dennis C / Mota, Talia M / Boucau, Julie / Garcia-Beltran, Wilfredo F / Jones, R. Brad F / Bieniasz, Paul D

    bioRxiv

    Abstract: Viruses employ a variety of strategies to escape or counteract immune responses, including depletion of cell surface major histocompatibility complex class I (MHC-I), that would ordinarily present viral peptides to CD8+ cytotoxic T cells. As part of a ... ...

    Abstract Viruses employ a variety of strategies to escape or counteract immune responses, including depletion of cell surface major histocompatibility complex class I (MHC-I), that would ordinarily present viral peptides to CD8+ cytotoxic T cells. As part of a screen to elucidate biological activities associated with individual SARS-CoV-2 viral proteins, we found that ORF7a reduced cell surface MHC-I levels by approximately 5-fold. Nevertheless, in cells infected with SARS-CoV-2, surface MHC-I levels were reduced even in the absence of ORF7a, suggesting additional mechanisms of MHC-I downregulation. ORF7a proteins from a sample of sarbecoviruses varied in their ability to induce MHC-I downregulation and, unlike SARS-CoV-2, the ORF7a protein from SARS-CoV lacked MHC-I downregulating activity. A single-amino acid at position 59 (T/F) that is variable among sarbecovirus ORF7a proteins governed the difference in MHC-I downregulating activity. SARS-CoV-2 ORF7a physically associated with the MHC-I heavy chain and inhibited the presentation of expressed antigen to CD8+ T-cells. Speficially, ORF7a prevented the assembly of the MHC-I peptide loading complex and causing retention of MHC-I in the endoplasmic reticulum. The differential ability of ORF7a proteins to function in this way might affect sarbecovirus dissemination and persistence in human populations, particularly those with infection- or vaccine-elicited immunity.
    Keywords covid19
    Language English
    Publishing date 2022-05-26
    Publisher Cold Spring Harbor Laboratory
    Document type Article ; Online
    DOI 10.1101/2022.05.25.493467
    Database COVID19

    Kategorien

  10. Article ; Online: Molecular fate-mapping of serum antibodies reveals the effects of antigenic imprinting on repeated immunization

    Schiepers, Arïen / van 't Wout, Marije FL / Greaney, Allison J / Zang, Trinity / Muramatsu, Hiromi / Lin, Paulo JC / Tam, Ying K / Mesin, Luka / Starr, Tyler N / Bieniasz, Paul D / Pardi, Norbert / Bloom, Jesse D / Victora, Gabriel D

    bioRxiv

    Abstract: The ability of serum antibody to protect against pathogens arises from the interplay of antigen-specific B cell clones of different affinities and fine specificities. These cellular dynamics are ultimately responsible for serum-level phenomena such as ... ...

    Abstract The ability of serum antibody to protect against pathogens arises from the interplay of antigen-specific B cell clones of different affinities and fine specificities. These cellular dynamics are ultimately responsible for serum-level phenomena such as antibody imprinting or "Original Antigenic Sin" (OAS), a proposed propensity of the immune system to rely repeatedly on the first cohort of B cells that responded to a stimulus upon exposure to related antigens. Imprinting/OAS is thought to pose a barrier to vaccination against rapidly evolving viruses such as influenza and SARS-CoV-2. Precise measurement of the extent to which imprinting/OAS inhibits the recruitment of new B cell clones by boosting is challenging because cellular and temporal origins cannot readily be assigned to antibodies in circulation. Thus, the extent to which imprinting/OAS impacts the induction of new responses in various settings remains unclear. To address this, we developed a "molecular fate-mapping" approach in which serum antibodies derived from specific cohorts of B cells can be differentially detected. We show that, upon sequential homologous boosting, the serum antibody response strongly favors reuse of the first cohort of B cell clones over the recruitment of new, naive-derived B cells. This "primary addiction" decreases as a function of antigenic distance, allowing secondary immunization with divergent influenza virus or SARS-CoV-2 glycoproteins to overcome imprinting/OAS by targeting novel epitopes absent from the priming variant. Our findings have implications for the understanding of imprinting/OAS, and for the design and testing of vaccines aimed at eliciting antibodies to evolving antigens.
    Keywords covid19
    Language English
    Publishing date 2022-08-30
    Publisher Cold Spring Harbor Laboratory
    Document type Article ; Online
    DOI 10.1101/2022.08.29.505743
    Database COVID19

    Kategorien

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