mRNA booster immunization elicits potent neutralizing serum activity against the SARS-CoV-2 Omicron variant

Abstract The Omicron variant of SARS-CoV-2 is causing a rapid increase in infections across the globe. This new variant of concern carries an unusually high number of mutations in key epitopes of neutralizing antibodies on the viral spike glycoprotein, suggesting potential immune evasion. Here we assessed serum neutralizing capacity in longitudinal cohorts of vaccinated and convalescent individuals, as well as monoclonal antibody activity against Omicron using pseudovirus neutralization assays. We report a near-complete lack of neutralizing activity against Omicron in polyclonal sera from individuals vaccinated with two doses of the BNT162b2 COVID-19 vaccine and from convalescent individuals, as well as resistance to different monoclonal antibodies in clinical use. However, mRNA booster immunizations in vaccinated and convalescent individuals resulted in a significant increase of serum neutralizing activity against Omicron. The presented study demonstrates that booster immunizations may be critical to substantially improve the humoral immune response against the Omicron variant.Authors Henning Gruell, Kanika Vanshylla, Florian Kurth, Leif E. Sander, and Florian Klein contributed equally to this work.

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mRNA booster immunization elicits potent neutralizing serum activity against the SARS-CoV-2 Omicron variant

10.1101/2021.12.14.21267769 ◽

2021 ◽

Author(s):

Henning Gruell ◽

Kanika Vanshylla ◽

Pinkus Tober-Lau ◽

David Hillus ◽

Philipp Schommers ◽

...

Keyword(s):

Monoclonal Antibody ◽

Immune Evasion ◽

Neutralizing Antibodies ◽

Antibody Activity ◽

Clinical Use ◽

Neutralizing Activity ◽

Booster Immunization ◽

Humoral Immune ◽

Neutralizing Capacity ◽

New Variant

The Omicron variant of SARS-CoV-2 is causing a rapid increase in infections in various countries. This new variant of concern carries an unusually high number of mutations in key epitopes of neutralizing antibodies on the spike glycoprotein, suggesting potential immune evasion. Here we assessed serum neutralizing capacity in longitudinal cohorts of vaccinated and convalescent individuals, as well as monoclonal antibody activity against Omicron using pseudovirus neutralization assays. We report a near-complete lack of neutralizing activity against Omicron in polyclonal sera after two doses of the BNT162b2 vaccine, in convalescent individuals, as well as resistance to different monoclonal antibodies in clinical use. However, mRNA booster immunizations in vaccinated and convalescent individuals resulted in a significant increase of serum neutralizing activity against Omicron. Our study demonstrates that booster immunizations will be critical to substantially improve the humoral immune response against the Omicron variant.

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The vaccinia-based Sementis Copenhagen Vector COVID-19 vaccine induces broad and durable cellular and humoral immune responses

10.1101/2021.09.06.459206 ◽

2021 ◽

Author(s):

Preethi Eldi ◽

Tamara H Cooper ◽

Natalie A Prow ◽

Liang Liu ◽

Gary K Heinemann ◽

...

Keyword(s):

Immune Responses ◽

Neutralizing Antibodies ◽

First Generation ◽

Neutralizing Antibody ◽

Immune Memory ◽

Antibody Activity ◽

Post Vaccination ◽

Humoral Immune ◽

Humoral Immune Responses ◽

Heterologous Boost

The ongoing COVID-19 pandemic perpetuated by SARS-CoV-2 variants, has highlighted the continued need for broadly protective vaccines that elicit robust and durable protection. Here, the vaccinia virus-based, replication-defective Sementis Copenhagen Vector (SCV) was used to develop a first-generation COVID-19 vaccine encoding the spike glycoprotein (SCV-S). Vaccination of mice rapidly induced polyfunctional CD8 T cells with cytotoxic activity and robust Th1-biased, spike-specific neutralizing antibodies, which are significantly increased following a second vaccination, and contained neutralizing activity against the alpha and beta variants of concern. Longitudinal studies indicated neutralizing antibody activity was maintained up to 9 months post-vaccination in both young and aging mice, with durable immune memory evident even in the presence of pre-existing vector immunity. This immunogenicity profile suggests a potential to expand protection generated by current vaccines in a heterologous boost format, and presents a solid basis for second-generation SCV-based COVID-19 vaccine candidates incorporating additional SARS-CoV-2 immunogens.

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The Porcine Humoral Immune Response against Pseudorabies Virus Specifically Targets Attachment Sites on Glycoprotein gC

Journal of Virology ◽

10.1128/jvi.74.4.1752-1760.2000 ◽

2000 ◽

Vol 74 (4) ◽

pp. 1752-1760 ◽

Cited By ~ 24

Author(s):

Bertram T. Ober ◽

Berthold Teufel ◽

Karl-Heinz Wiesmüller ◽

Günther Jung ◽

Eberhard Pfaff ◽

...

Keyword(s):

Immune Response ◽

Humoral Immune Response ◽

Neutralizing Antibodies ◽

Pseudorabies Virus ◽

Host Protein ◽

Target Cells ◽

Heparin Binding ◽

Viral Attachment ◽

Neutralizing Activity ◽

Humoral Immune

ABSTRACT High titers of virus-neutralizing antibodies directed against glycoprotein gC of Pseudorabies virus (PRV) (Suid herpesvirus 1) are generally observed in the serum of immunized pigs. A known function of the glycoprotein gC is to mediate attachment of PRV to target cells through distinct viral heparin-binding domains (HBDs). Therefore, it was suggested that the virus-neutralizing activity of anti-PRV sera is directed against HBDs on gC. To address this issue, sera with high virus-neutralizing activity against gC were used to characterize the anti-gC response. Epitope mapping demonstrated that amino acids of HBDs are part of an antigenic antibody binding domain which is located in the N-terminal part of gC. Binding of antibodies to this antigenic domain of gC was further shown to interfere with the viral attachment. Therefore, these results show that the viral HBDs are accessible targets for the humoral anti-PRV response even after tolerance induction against self-proteins, which utilize similar HBDs to promote host protein-protein interactions. The findings indicate that the host's immune system can specifically block the attachment function of PRV gC. Since HBDs promote the attachment of a number of herpesviruses, the design of future antiherpesvirus vaccines should aim to induce a humoral immune response that prevents HBD-mediated viral attachment.

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Identification of Neutralizing and Nonneutralizing Epitopes in the Porcine Reproductive and Respiratory Syndrome Virus GP5 Ectodomain

Journal of Virology ◽

10.1128/jvi.76.9.4241-4250.2002 ◽

2002 ◽

Vol 76 (9) ◽

pp. 4241-4250 ◽

Cited By ~ 286

Author(s):

M. Ostrowski ◽

J. A. Galeota ◽

A. M. Jar ◽

K. B. Platt ◽

F. A. Osorio ◽

...

Keyword(s):

Monoclonal Antibody ◽

Phage Display ◽

Neutralizing Antibodies ◽

Phage Display Library ◽

The Other ◽

Respiratory Syndrome Virus ◽

Rapid Rise ◽

Neutralizing Activity ◽

Neutralizing Monoclonal Antibody ◽

Neutralizing Epitopes

ABSTRACT After infection of swine with porcine reproductive and respiratory syndrome virus (PRRSV), there is a rapid rise of PRRSV-specific nonneutralizing antibodies (NNA), while neutralizing antibodies (NA) are detectable not sooner than 3 weeks later. To characterize neutralizing epitopes, we selected phages from a 12-mer phage display library using anti-PRRSV neutralizing monoclonal antibody (MAb) ISU25-C1. In addition, phages carrying peptides recognized by swine antibodies with high seroneutralizing titer were isolated after subtracting from the library those clones binding to swine anti-PRRSV serum with no neutralizing activity. Two epitopes located in the ectodomain of PRRSV GP5 were identified. One of these epitopes, which we named epitope B, was recognized both by neutralizing MAb ISU25-C1 and swine neutralizing serum (NS) but not by swine nonneutralizing serum (NNS), indicating that it is a neutralizing epitope. Epitope B is sequential, conserved among isolates, and not immunodominant. Antibodies directed against it are detected in serum late after infection. In contrast, the other epitope, which we named epitope A, is hypervariable and immunodominant. Antibodies against it appear early after infection with PRRSV. This epitope is recognized by swine NNA but is not recognized by either neutralizing MAb ISU25-C1 or swine NA, indicating that it is not involved in PRRSV neutralization. During infection with PRRSV, epitope A may act as a decoy, eliciting most of the antibodies directed to GP5 and delaying the induction of NA against epitope B for at least 3 weeks. These results are relevant to the design of vaccines against PRRSV.

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Characterization of the Humoral Immune Response Induced after Infection with Atypical Porcine Pestivirus (APPV)

Viruses ◽

10.3390/v11100880 ◽

2019 ◽

Vol 11 (10) ◽

pp. 880 ◽

Cited By ~ 4

Author(s):

Gökce Nur Cagatay ◽

Denise Meyer ◽

Michael Wendt ◽

Paul Becher ◽

Alexander Postel

Keyword(s):

Immune Response ◽

Humoral Immune Response ◽

Neutralizing Antibodies ◽

Neutralizing Antibody ◽

Humoral Immune ◽

Neutralizing Capacity ◽

Antibody Titers ◽

Antibody Levels ◽

Congenital Tremor

Atypical porcine pestivirus (APPV) is a widely distributed pathogen causing congenital tremor (CT) in piglets. So far, no data are available regarding the humoral immune response against APPV. In this study, piglets and their sows from an affected herd were tested longitudinally for viral genome and antibodies. APPV genome was detected in the majority of the piglets (14/15) from CT affected litters. Transient infection of gilts was observed. Kinetics of Erns- and E2-specific antibodies and their neutralizing capacity were determined by recently (Erns) and newly (E2) developed antibody ELISAs and virus neutralization assays. Putative maternally derived antibodies (MDA) were detected in most piglets, but displayed only low to moderate neutralizing capacity (ND50 ≤ 112). Horizontal APPV transmission occurred when uninfected and infected piglets were mingled on the flat deck. Horizontally infected piglets were clinically inapparent and showed only transient viremia with subsequently consistently high E2 antibody levels. For piglets from CT affected litters, significantly lower neutralizing antibody titers were observed. Results indicate that E2 represents the main target of neutralizing antibodies. Characterization of the humoral immune response against APPV will help to provide valuable serological diagnosis, to understand the epidemiology of this novel pathogen, and to implement tailored prevention strategies.

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Virus Evolution and Neutralization Sensitivity in an HIV-1 Subtype B′ Infected Plasma Donor with Broadly Neutralizing Activity

Vaccines ◽

10.3390/vaccines9040311 ◽

2021 ◽

Vol 9 (4) ◽

pp. 311

Author(s):

Yuanyuan Hu ◽

Sen Zou ◽

Zheng Wang ◽

Ying Liu ◽

Li Ren ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Neutralization Sensitivity ◽

Autologous Plasma ◽

Neutralizing Activity ◽

Humoral Immune ◽

Immune Pressure ◽

Subtype B ◽

Immunogen Design ◽

Plasma Donor ◽

Hiv 1

We sought to analyze the evolutionary characteristics and neutralization sensitivity of viruses in a human immunodeficiency virus type 1 (HIV-1) subtype B′ infected plasma donor with broadly neutralizing activity, which may provide information for new broadly neutralizing antibodies (bNAbs) isolation and immunogen design. A total of 83 full-length envelope genes were obtained by single-genome amplification (SGA) from the patient’s plasma at three consecutive time points (2005, 2006, and 2008) spanning four years. In addition, 28 Env-pseudotyped viruses were constructed and their neutralization sensitivity to autologous plasma and several representative bNAbs were measured. Phylogenetic analysis showed that these env sequences formed two evolutionary clusters (Cluster I and II). Cluster I viruses vanished in 2006 and then appeared as recombinants two years later. In Cluster II viruses, the V1 length and N-glycosylation sites increased over the four years of the study period. Most viruses were sensitive to concurrent and subsequent autologous plasma, and to bNAbs, including 10E8, PGT121, VRC01, and 12A21, but all viruses were resistant to PGT135. Overall, 90% of Cluster I viruses were resistant to 2G12, while 94% of Cluster II viruses were sensitive to 2G12. We confirmed that HIV-1 continued to evolve even in the presence of bNAbs, and two virus clusters in this donor adopted different escape mechanisms under the same humoral immune pressure.

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Humoral immune response to circulating SARS-CoV-2 variants elicited by inactivated and RBD-subunit vaccines

Cell Research ◽

10.1038/s41422-021-00514-9 ◽

2021 ◽

Author(s):

Yunlong Cao ◽

Ayijiang Yisimayi ◽

Yali Bai ◽

Weijin Huang ◽

Xiaofeng Li ◽

...

Keyword(s):

Immune Response ◽

Humoral Immune Response ◽

Neutralizing Antibodies ◽

Mononuclear Cells ◽

Immune Escape ◽

Natural Infection ◽

Peripheral Blood Mononuclear ◽

Neutralizing Activity ◽

Humoral Immune ◽

Complementarity Determining Regions

AbstractSARS-CoV-2 variants could induce immune escape by mutations on the receptor-binding domain (RBD) and N-terminal domain (NTD). Here we report the humoral immune response to circulating SARS-CoV-2 variants, such as 501Y.V2 (B.1.351), of the plasma and neutralizing antibodies (NAbs) elicited by CoronaVac (inactivated vaccine), ZF2001 (RBD-subunit vaccine) and natural infection. Among 86 potent NAbs identified by high-throughput single-cell VDJ sequencing of peripheral blood mononuclear cells from vaccinees and convalescents, near half anti-RBD NAbs showed major neutralization reductions against the K417N/E484K/N501Y mutation combination, with E484K being the dominant cause. VH3-53/VH3-66 recurrent antibodies respond differently to RBD variants, and K417N compromises the majority of neutralizing activity through reduced polar contacts with complementarity determining regions. In contrast, the 242–244 deletion (242–244Δ) would abolish most neutralization activity of anti-NTD NAbs by interrupting the conformation of NTD antigenic supersite, indicating a much less diversity of anti-NTD NAbs than anti-RBD NAbs. Plasma of convalescents and CoronaVac vaccinees displayed comparable neutralization reductions against pseudo- and authentic 501Y.V2 variants, mainly caused by E484K/N501Y and 242–244Δ, with the effects being additive. Importantly, RBD-subunit vaccinees exhibit markedly higher tolerance to 501Y.V2 than convalescents, since the elicited anti-RBD NAbs display a high diversity and are unaffected by NTD mutations. Moreover, an extended gap between the third and second doses of ZF2001 leads to better neutralizing activity and tolerance to 501Y.V2 than the standard three-dose administration. Together, these results suggest that the deployment of RBD-vaccines, through a third-dose boost, may be ideal for combating SARS-CoV-2 variants when necessary, especially for those carrying mutations that disrupt the NTD supersite.

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Functional and Structural Characterization of Human V3-Specific Monoclonal Antibody 2424 with Neutralizing Activity against HIV-1 JRFL

Journal of Virology ◽

10.1128/jvi.01280-15 ◽

2015 ◽

Vol 89 (17) ◽

pp. 9090-9102 ◽

Cited By ~ 8

Author(s):

Rajnish Kumar ◽

Ruimin Pan ◽

Chitra Upadhyay ◽

Luzia Mayr ◽

Sandra Cohen ◽

...

Keyword(s):

Monoclonal Antibody ◽

Neutralizing Antibodies ◽

Vaccine Development ◽

Binding Mode ◽

Hiv Vaccine ◽

The Other ◽

Specific Monoclonal Antibody ◽

Virus Envelope ◽

Neutralizing Activity ◽

Hiv 1

ABSTRACTThe V3 region of HIV-1 gp120 is important for virus-coreceptor interaction and highly immunogenic. Although most anti-V3 antibodies neutralize only the sensitive tier 1 viruses, anti-V3 antibodies effective against the more resistant viruses exist, and a better understanding of these antibodies and their epitopes would be beneficial for the development of novel vaccine immunogens against HIV. The HIV-1 isolate JRFL with its cryptic V3 is resistant to most V3-specific monoclonal antibodies (MAbs). However, the V3 MAb 2424 achieves 100% neutralization against JRFL. 2424 is encoded by IGHV3-53 and IGLV2-28 genes, a pairing rarely used by the other V3 MAbs. 2424 also has distinct binding and neutralization profiles. Studies of 2424-mediated neutralization of JRFL produced with a mannosidase inhibitor further revealed that its neutralizing activity is unaffected by the glycan composition of the virus envelope. To understand the distinct activity of 2424, we determined the crystal structure of 2424 Fab in complex with a JRFL V3 peptide and showed that the 2424 epitope is located at the tip of the V3 crown (307IHIGPGRAFYT319), dominated by interactions with HisP308, ProP313, and ArgP315. The binding mode of 2424 is similar to that of the well-characterized MAb 447-52D, although 2424 is more side chain dependent. The 2424 epitope is focused on the very apex of V3, away from nearby glycans, facilitating antibody access. This feature distinguishes the 2424 epitope from the other V3 crown epitopes and indicates that the tip of V3 is a potential site to target and incorporate into HIV vaccine immunogens.IMPORTANCEHIV/AIDS vaccines are crucial for controlling the HIV epidemics that continue to afflict millions of people worldwide. However, HIV vaccine development has been hampered by significant scientific challenges, one of which is the inability of HIV vaccine candidates evaluated thus far to elicit production of potent and broadly neutralizing antibodies. The V3 loop is one of the few immunogenic targets on the virus envelope glycoprotein that can induce neutralizing antibodies, but in many viruses, parts of V3 are inaccessible for antibody recognition. This study examined a V3-specific monoclonal antibody that can completely neutralize HIV-1 JRFL, a virus isolate resistant to most V3 antibodies. Our data reveal that this antibody recognizes the most distal tip of V3, which is not as occluded as other parts of V3. Hence, the epitope of 2424 is in one of the vulnerable sites on the virus that may be exploited in designing HIV vaccine immunogens.

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B.1.1.529 escapes the majority of SARS-CoV-2 neutralizing antibodies of diverse epitopes

10.21203/rs.3.rs-1148985/v1 ◽

2021 ◽

Author(s):

Xiaoliang Xie ◽

Yunlong Cao ◽

jing wang ◽

Fanchong Jian ◽

Tianhe Xiao ◽

...

Keyword(s):

Immune Evasion ◽

Neutralizing Antibodies ◽

Binding Assay ◽

Binding Motif ◽

Single Mutation ◽

Receptor Binding Domain ◽

Yeast Display ◽

Humoral Immune ◽

Knowledge Based ◽

Group A

Abstract The SARS-CoV-2 B.1.1.529 variant (Omicron) contains 15 mutations on the receptor-binding domain (RBD). How Omicron would evade RBD neutralizing antibodies (NAbs) and humoral immunity requires immediate investigation. Here, we used high-throughput yeast display screening1,2 to determine the RBD escaping mutation profiles for 247 human anti-RBD NAbs identified from SARS-CoV/SARS-CoV-2 convalescents and vaccinees. Based on the results, NAbs could be unsupervised clustered into six epitope groups (A-F), which is highly concordant with knowledge-based structural classifications3-5. Strikingly, various single mutations of Omicron could impair NAbs of different epitope groups. Specifically, NAbs in Group A-D, whose epitope overlaps with ACE2-binding motif, are largely escaped by K417N, N440K, G446S, E484A, Q493K, and G496S. Group E (S309 site)6 and F (CR3022 site)7 NAbs, which often exhibit broad sarbecovirus neutralizing activity, are less affected by Omicron, but still, a subset of NAbs are escaped by G339D, S371L, and S375F. Furthermore, B.1.1.529 pseudovirus neutralization and RBD binding assay showed that single mutation tolerating NAbs could also be escaped due to multiple synergetic mutations on their epitopes. In total, over 85% of the tested NAbs are escaped by Omicron. Regarding NAb drugs, LY-CoV016/LY-CoV555 cocktail, REGN-CoV2 cocktail, AZD1061/AZD8895 cocktail, and BRII-196 were escaped by Omicron, while VIR7831 and DXP-604 still function at reduced efficacy. Together, data suggest Omicron could cause significant humoral immune evasion, while NAbs targeting the sarbecovirus conserved region remain most effective. Our results offer instructions for developing NAb drugs and vaccines against Omicron and future variants.

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B.1.1.529 escapes the majority of SARS-CoV-2 neutralizing antibodies of diverse epitopes

10.1101/2021.12.07.470392 ◽

2021 ◽

Author(s):

Yunlong Richard Cao ◽

Jing Wang ◽

Fanchong Jian ◽

Tianhe Xiao ◽

Weiliang Song ◽

...

Keyword(s):

Immune Evasion ◽

Neutralizing Antibodies ◽

Binding Assay ◽

Binding Motif ◽

Single Mutation ◽

Receptor Binding Domain ◽

Yeast Display ◽

Humoral Immune ◽

Knowledge Based ◽

Group A

The SARS-CoV-2 B.1.1.529 variant (Omicron) contains 15 mutations on the receptor-binding domain (RBD). How Omicron would evade RBD neutralizing antibodies (NAbs) and humoral immunity requires immediate investigation. Here, we used high-throughput yeast display screening to determine the RBD escaping mutation profiles for 247 human anti-RBD NAbs identified from SARS-CoV/SARS-CoV-2 convalescents and vaccinees. Based on the results, NAbs could be unsupervised clustered into six epitope groups (A-F), which is highly concordant with knowledge-based structural classifications. Strikingly, various single mutations of Omicron could impair NAbs of different epitope groups. Specifically, NAbs in Group A-D, whose epitope overlaps with ACE2-binding motif, are largely escaped by K417N, N440K, G446S, E484A, Q493K, and G496S. Group E (S309 site) and F (CR3022 site) NAbs, which often exhibit broad sarbecovirus neutralizing activity, are less affected by Omicron, but still, a subset of NAbs are escaped by G339D, S371L, and S375F. Furthermore, B.1.1.529 pseudovirus neutralization and RBD binding assay showed that single mutation tolerating NAbs could also be escaped due to multiple synergetic mutations on their epitopes. In total, over 85% of the tested NAbs are escaped by Omicron. Regarding NAb drugs, LY-CoV016/LY-CoV555 cocktail, REGN-CoV2 cocktail, AZD1061/AZD8895 cocktail, and BRII-196 were escaped by Omicron, while VIR7831 and DXP-604 still function at reduced efficacy. Together, data suggest Omicron could cause significant humoral immune evasion, while NAbs targeting the sarbecovirus conserved region remain most effective. Our results offer instructions for developing NAb drugs and vaccines against Omicron and future variants.

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