Protective antibodies elicited by SARS-CoV-2 spike protein vaccination are boosted in the lung after challenge in nonhuman primates

Adjuvanted soluble protein vaccines have been used extensively in humans for protection against various viral infections based on their robust induction of antibody responses. Here, soluble prefusion-stabilized spike protein trimers (preS dTM) from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were formulated with the adjuvant AS03 and administered twice to nonhuman primates (NHP). Binding and functional neutralization assays and systems serology revealed that the vaccinated NHP developed AS03-dependent multi-functional humoral responses that targeted distinct domains of the spike protein and bound to a variety of FC receptors mediating immune cell effector functions in vitro. The neutralizing 50% inhibitory concentration (IC50) titers for pseudovirus and live SARS-CoV-2 were higher than titers for a panel of human convalescent serum samples. NHP were challenged intranasally and intratracheally with a high dose (3x106 plaque forming units, PFU) of SARS-CoV-2 (USA-WA1/2020 isolate). Two days post-challenge, vaccinated NHP showed rapid control of viral replication in both the upper and lower airways. Notably, vaccinated NHP also had increased spike protein-specific IgG antibody responses in the lung as early as two days post challenge. Moreover, passive transfer of vaccine-induced IgG to hamsters mediated protection from subsequent SARS-CoV-2 challenge. These data show that antibodies induced by the AS03-adjuvanted preS dTM vaccine were sufficient to mediate protection against SARS-CoV-2 in NHP and that rapid anamnestic antibody responses in the lung may be a key mechanism for protection.

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Vaccination with SARS-CoV-2 Spike Protein and AS03 Adjuvant Induces Rapid Anamnestic Antibodies in the Lung and Protects Against Virus Challenge in Nonhuman Primates

10.1101/2021.03.02.433390 ◽

2021 ◽

Cited By ~ 1

Author(s):

Joseph R. Francica ◽

Barbara J. Flynn ◽

Kathryn E. Foulds ◽

Amy T. Noe ◽

Anne P. Werner ◽

...

Keyword(s):

Nonhuman Primates ◽

Viral Infections ◽

Antibody Responses ◽

High Dose ◽

Post Challenge ◽

Igg Antibody ◽

Live Virus ◽

Virus Challenge ◽

Humoral Responses

AbstractAdjuvanted soluble protein vaccines have been used extensively in humans for protection against various viral infections based on their robust induction of antibody responses. Here, soluble prefusion-stabilized spike trimers (preS dTM) from the severe acute respiratory syndrome coronavirus (SARS-CoV-2) were formulated with the adjuvant AS03 and administered twice to nonhuman primates (NHP). Binding and functional neutralization assays and systems serology revealed that NHP developed AS03-dependent multi-functional humoral responses that targeted multiple spike domains and bound to a variety of antibody FC receptors mediating effector functions in vitro. Pseudovirus and live virus neutralizing IC50 titers were on average greater than 1000 and significantly higher than a panel of human convalescent sera. NHP were challenged intranasally and intratracheally with a high dose (3×106 PFU) of SARS-CoV-2 (USA-WA1/2020 isolate). Two days post-challenge, vaccinated NHP showed rapid control of viral replication in both the upper and lower airways. Notably, vaccinated NHP also had increased spike-specific IgG antibody responses in the lung as early as 2 days post challenge. Moreover, vaccine-induced IgG mediated protection from SARS-CoV-2 challenge following passive transfer to hamsters. These data show that antibodies induced by the AS03-adjuvanted preS dTM vaccine are sufficient to mediate protection against SARS-CoV-2 and support the evaluation of this vaccine in human clinical trials.

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Long-term persistence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein-specific and neutralizing antibodies in recovered COVID-19 patients

10.21203/rs.3.rs-1073046/v1 ◽

2021 ◽

Author(s):

Jira Chansaenroj ◽

Ritthideach Yorsaeng ◽

Nasamon Wanlapakorn ◽

Chintana Chirathaworn ◽

Natthinee Sudhinaraset ◽

...

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Symptom Onset ◽

Neutralizing Antibodies ◽

Serum Antibody ◽

Neutralizing Antibody ◽

Antibody Responses ◽

Spike Protein ◽

Immunological Study ◽

Igg Antibody ◽

Vaccine Schedule

Abstract Understanding antibody responses after natural severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can guide the coronavirus disease 2019 (COVID-19) vaccine schedule. This study aimed to assess the dynamics of SARS-CoV-2 antibodies, including anti-spike protein 1 (S1) immunoglobulin (Ig)G, anti-receptor-binding domain (RBD) total Ig, anti-S1 IgA, and neutralizing antibody against wild-type SARS-CoV-2 in a cohort of patients who were previously infected with SARS-CoV-2. Between March and May 2020, 531 individuals with virologically confirmed cases of SARS-CoV-2 infection were enrolled in our immunological study. The neutralizing titers against SARS-CoV-2 were detected in 95.2%, 86.7%, 85.0%, and 85.4% of recovered COVID-19 patients at 3, 6, 9, and 12 months after symptom onset, respectively. The seropositivity rate of anti-S1 IgG, anti-RBD total Ig, anti-S1 IgA, and neutralizing titers remained at 68.6%, 89.6%, 77.1%, and 85.4%, respectively, at 12 months after symptom onset. The half-life of neutralizing titers was estimated at 100.7 days (95% confidence interval = 44.5 – 327.4 days, R2 = 0.106). These results support that the decline in serum antibody levels over time depends on the symptom severity, and the individuals with high IgG antibody titers experienced a significantly longer persistence of SARS-CoV-2-specific antibody responses than those with lower titers.

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Longitudinal Analysis of Cryptosporidium Species-Specific Immunoglobulin G Antibody Responses in Peruvian Children

Clinical and Vaccine Immunology ◽

10.1128/cvi.13.1.123-131.2006 ◽

2006 ◽

Vol 13 (1) ◽

pp. 123-131 ◽

Cited By ~ 43

Author(s):

Jeffrey W. Priest ◽

Caryn Bern ◽

Lihua Xiao ◽

Jacquelin M. Roberts ◽

James P. Kwon ◽

...

Keyword(s):

Immunoglobulin G ◽

Antibody Responses ◽

Health Interventions ◽

Older Children ◽

Serum Samples ◽

Igg Antibody ◽

Specific Immunoglobulin ◽

Antibody Assays ◽

Species Specific ◽

Antibody Levels

ABSTRACT Cryptosporidium species are ubiquitous in the environment and are frequently detected in the stools of children who live where sanitation conditions are poor. To better characterize the immune response to these parasites, we monitored immunoglobulin G (IgG) antibody levels in a cohort of children from Lima, Peru. Two new enzyme-linked immunosorbent assays based on the C. parvum (bovine, subtype IIa) Iowa strain 17-kDa and 27-kDa antigens were used to measure IgG antibody levels in longitudinal serum samples. Antibody responses were detected during infections with C. parvum, C. felis, and C. meleagridis and with four different subtypes of C. hominis. We also noted that the magnitude of the antibody response was related to the number of previous infections and that older children generally had higher levels of antibodies to the two C. parvum antigens. Antibody responses were not associated with infections with either Cyclospora sp. or Giardia sp. We believe the antibody assays will be important tools for monitoring the success of future public health interventions.

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High-Dose IgG Alters the Relative Expression of Fcgamma RIIA and Fcgamma RIIB On Human Macrophages: A Mechanism for IVIG Therapy in Human Immune Thrombocytopenia.

Blood ◽

10.1182/blood.v114.22.683.683 ◽

2009 ◽

Vol 114 (22) ◽

pp. 683-683 ◽

Cited By ~ 1

Author(s):

Salley Pels ◽

Caroline Tang ◽

Mehmet Ertem ◽

Diana S. Beardsley

Keyword(s):

Board Of Directors ◽

Immune Thrombocytopenia ◽

Ivig Therapy ◽

High Dose ◽

Igg Antibody ◽

Platelet Destruction ◽

Advisory Committees ◽

Human Macrophages ◽

Human Immune

Abstract Abstract 683 The pathogenic mechanism of immune thrombocytopenia involves antibody mediated destruction of platelets in the reticuloendothelial system. Infection often triggers an exacerbation of thrombocytopenia in patients with ITP that may be treated with intravenous immunoglobulin (IVIG). However, the precise mechanism of action of IVIG has not been clearly elucidated. Studies by McKenzie et al. (Journal of Immunology, 1999) in an animal model for immune thrombocytopenia (ITP) using a mouse transgenic for human activating receptor FcgammaRIIA and lacking murine activating receptors FcgammaRI and FcgammaRIII revealed that human FcgammaRIIA is necessary for antibody mediated platelet destruction. (Murine macrophages lack an analogous activating FcgammaRII.) In another animal model of ITP, Samuelsson et al. (Science, 2001) showed that decreased expression of the murine inhibiting FcgammaRIIb was associated with increased platelet destruction that was not responsive to IVIG. The present studies were undertaken to test the hypothesis that human antibody mediated platelet phagocytosis depends upon the balance between the activating (FcgammaRIIA) and inhibiting (FcgammaRIIB) receptors on human macrophages and that IVIG alters this balance by increasing the expression of the inhibiting receptor. We additionally hypothesized that infection results in decreased FcgammaRIIB expression and enhanced phagocytosis that may be abrogated by IVIG. Methods: Antibody-mediated phagocytosis of platelets by THP-1 (human macrophage) cells in culture was assayed by co-incubation of THP-1 cells with anti-platelet antibody as a model for human immune mediated platelet destruction. Platelets were labeled with 5-(and 6-) carboxyfluorescein diacetate mixed isomers (CFDA) in the presence of human serum containing anti-HPA 1a IgG antibody. Macrophages that had ingested human platelets were identified by flow cytometry as previously reported. To study the mechanism of action of IVIG therapy for immune thrombocytopenia, in vitro phagocytosis was assayed after the addition of purified IgG (100mg/ml) to the THP-1 cells 30 minutes prior to exposure of the labeled platelets to anti-HPA 1a IgG antibody. The effect of LPS on platelet phagocytosis was studied as a model for infection which can exacerbate immune platelet destruction. Phagocytosis was assayed before and after incubation with LPS (1ug/ml) for 2 hours at 37 degrees Celsius. For each experiment, total FcgammaRIIA (CD32A) and FcgammaRIIB (CD32B) were determined by immunoprecipitation and immunoblotting. Results: Pretreatment with IVIG had no effect on FcgammaRIIA (n=3) expression; however, FcgammaRIIB expression increased an average of 5 fold (n=6). Addition of LPS alone resulted in marked decrease in expression of FcgammaRIIB for up to 60 minutes; however, FcgammaRIIA did not change. Experiments performed with addition of both IVIG and LPS showed that FcgammaRIIB expression remained elevated 3 fold (n=3). Following increased expression of FcgammaRIIB, IgG exposure resulted in decreased phagocytosis as assayed by flow cytometric analysis of macrophage ingestion of CFDA-labeled platelets. Antibody mediated platelet phagocytosis by THP-1 cells was enhanced 26% by LPS after a 2 hour incubation (median increase in 5 experiments; range = 14-125%.) Conclusions: Exposure to high dose IgG increased the expression of FcgammaRIIB but had no effect on FcgammaRIIA. Therefore, the net functional effect was to tip the balance toward inhibition of antibody-mediated phagocytosis, as was observed in our in vitro assay of human platelet phagocytosis. Furthermore, treatment with IgG was able to partially overcome the negative effects of LPS on expression of the inhibiting receptor, FcgammaRIIB. These data clearly support the hypothesis that the balance of the activating (FcgammaRIIA) and inhibiting (FcgammaRIIB) receptors is important in mediating the therapeutic effects of IVIG as a treatment for human immune thrombocytopenia. Disclosures: Pels: National Hemophilia Foundation-Baxter: NHF-Baxter Clinical Fellowship Awardee, Research Funding. Beardsley:ITP Foundation: Membership on an entity's Board of Directors or advisory committees; Genzyme: Consultancy; Amgen: Membership on an entity's Board of Directors or advisory committees.

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Role of B7 Costimulatory Molecules in Mediating Systemic and Mucosal Antibody Responses to Attenuated Salmonella enterica Serovar Typhimurium and Its Cloned Antigen

Infection and Immunity ◽

10.1128/iai.72.10.5824-5831.2004 ◽

2004 ◽

Vol 72 (10) ◽

pp. 5824-5831 ◽

Cited By ~ 4

Author(s):

Carlos A. Garcia ◽

Michael Martin ◽

Suzanne M. Michalek

Keyword(s):

Salmonella Enterica ◽

Immunoglobulin A ◽

Costimulatory Molecules ◽

Antibody Responses ◽

Wild Type ◽

Igg Antibody ◽

Functional Roles ◽

Serovar Typhimurium

ABSTRACT The purpose of the present study was to evaluate the ability of an attenuated Salmonella enterica serovar Typhimurium vaccine strain to up-regulate B7-1 and B7-2 on antigen-presenting cells and to examine the functional roles these costimulatory molecules play in mediating immune responses to Salmonella and to an expressed cloned antigen, the saliva-binding region (SBR) of antigen I/II. In vitro stimulation of B cells (B220+), macrophages (CD11b+), and dendritic cells (CD11c+) with S. enterica serovar Typhimurium induced an up-regulation of B7-2 and, especially, B7-1 expression. The in vivo functional roles of B7-1, B7-2, and B7-1/2 were evaluated in BALB/c wild-type and B7-1, B7-2, and B7-1/2 knockout (KO) mice following intranasal immunization with the Salmonella expressing the cloned SBR. Differential requirements for B7-1 and B7-2 were observed upon primary and secondary immunizations. Compared to wild-type controls, B7-1 and B7-2 KO mice had reduced mucosal and systemic anti-Salmonella antibody responses after a single immunization, while only B7-1 KO mice exhibited suppressed anti-Salmonella antibody responses following the second immunization. Mucosal and systemic antibody responses to SBR were reduced following the primary immunization, whereas a compensatory role for either B7-1 or B7-2 was observed after the second immunization. B7-1/2 double KO mice failed to induce detectable levels of mucosal or systemic immunoglobulin A (IgA) or IgG antibody responses to either Salmonella or SBR. These findings demonstrate that B7-1 and B7-2 can play distinct as well as redundant roles for mediating mucosal and systemic antibody responses, which are likely dependent upon the nature of the antigen.

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Mathematical Modeling of Within-Host, Untreated, Cytomegalovirus Infection Dynamics after Allogeneic Transplantation

Viruses ◽

10.3390/v13112292 ◽

2021 ◽

Vol 13 (11) ◽

pp. 2292

Author(s):

Elizabeth R. Duke ◽

Florencia A. T. Boshier ◽

Michael Boeckh ◽

Joshua T. Schiffer ◽

E. Fabian Cardozo-Ojeda

Keyword(s):

Mathematical Modeling ◽

Immune Response ◽

Target Cell ◽

Hematopoietic Cell Transplantation ◽

Viral Infections ◽

Immune Cell ◽

Controlled Trial ◽

Antiviral Treatment ◽

Serum Samples ◽

Cell Compartments

Cytomegalovirus (CMV) causes significant morbidity and mortality in recipients of allogeneic hematopoietic cell transplantation (HCT). Whereas insights gained from mathematical modeling of other chronic viral infections such as HIV, hepatitis C, and herpes simplex virus-2 have aided in optimizing therapy, previous CMV modeling has been hindered by a lack of comprehensive quantitative PCR viral load data from untreated episodes of viremia in HCT recipients. We performed quantitative CMV DNA PCR on stored, frozen serum samples from the placebo group of participants in a historic randomized controlled trial of ganciclovir for the early treatment of CMV infection in bone marrow transplant recipients. We developed four main ordinary differential Equation mathematical models and used model selection theory to choose between 38 competing versions of these models. Models were fit using a population, nonlinear, mixed-effects approach. We found that CMV kinetics from untreated HCT recipients are highly variable. The models that recapitulated the observed patterns most parsimoniously included explicit, dynamic immune cell compartments and did not include dynamic target cell compartments, consistent with the large number of tissue and cell types that CMV infects. In addition, in our best-fitting models, viral clearance was extremely slow, suggesting severe impairment of the immune response after HCT. Parameters from our best model correlated well with participants’ clinical risk factors and outcomes from the trial, further validating our model. Our models suggest that CMV dynamics in HCT recipients are determined by host immune response rather than target cell limitation in the absence of antiviral treatment.

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Two doses of the SARS-CoV-2 BNT162b2 vaccine enhances antibody responses to variants in individuals with prior SARS-CoV-2 infection

Science Translational Medicine ◽

10.1126/scitranslmed.abj0847 ◽

2021 ◽

pp. eabj0847

Author(s):

Richard A Urbanowicz ◽

Theocharis Tsoleridis ◽

Hannah J Jackson ◽

Lola Cusin ◽

Joshua D Duncan ◽

...

Keyword(s):

Immune Responses ◽

Natural Infection ◽

Neutralizing Antibody ◽

Spike Protein ◽

Serum Samples ◽

Igg Antibody ◽

Enzyme Immunoassays ◽

Antigenic Exposure ◽

The Impact ◽

Prior Infection

Understanding the impact of prior infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on the response to vaccination is a priority for responding to the coronavirus disease 2019 (COVID-19) pandemic. In particular, it is necessary to understand how prior infection plus vaccination can modulate immune responses against variants of concern. To address this, we sampled 20 individuals with and 25 individuals without confirmed previous SARS-CoV-2 infection from a large cohort of healthcare workers followed serologically since April 2020. All 45 individuals had received two doses of the Pfizer-BioNTech BTN162b2 vaccine with a delayed booster at 10 weeks. Absolute and neutralizing antibody titers against wild-type SARS-CoV-2 and variants were measured using enzyme immunoassays and pseudotype neutralization assays. We observed antibody reactivity against lineage A, B.1.351 and P.1 variants with increasing antigenic exposure, either through vaccination or natural infection. This improvement was further confirmed in neutralization assays using fixed dilutions of serum samples. The impact of antigenic exposure was more evident in enzyme immunoassays measuring SARS-CoV-2 spike protein-specific IgG antibody concentrations. Our data show that multiple exposures to SARS-CoV-2 spike protein in the context of a delayed booster expand the neutralizing breadth of the antibody response to neutralization-resistant SARS-CoV-2 variants. This suggests that additional vaccine boosts may be beneficial in improving immune responses against future SARS-CoV-2 variants of concern.

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Differences in IgG Antibody Responses following BNT162b2 and mRNA-1273 SARS-CoV-2 Vaccines

Microbiology Spectrum ◽

10.1128/spectrum.01162-21 ◽

2021 ◽

Author(s):

José G. Montoya ◽

Amy E. Adams ◽

Valérie Bonetti ◽

Sien Deng ◽

Nan A. Link ◽

...

Keyword(s):

Immune System ◽

Human Cells ◽

Antibody Responses ◽

Spike Protein ◽

Severe Illness ◽

Igg Antibody

SARS-CoV-2 vaccines using the mRNA platform have become one of the most powerful tools to overcome the COVID-19 pandemic. mRNA vaccines enable human cells to produce and present the virus spike protein to their immune system, leading to protection from severe illness. Two mRNA vaccines have been widely implemented, mRNA-1273 (Moderna) and BNT162b2 (Pfizer/BioNTech).

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Ad26 vaccine protects against SARS-CoV-2 severe clinical disease in hamsters

Nature Medicine ◽

10.1038/s41591-020-1070-6 ◽

2020 ◽

Vol 26 (11) ◽

pp. 1694-1700 ◽

Cited By ~ 12

Author(s):

Lisa H. Tostanoski ◽

Frank Wegmann ◽

Amanda J. Martinot ◽

Carolin Loos ◽

Katherine McMahan ◽

...

Keyword(s):

Weight Loss ◽

Nonhuman Primates ◽

Severe Pneumonia ◽

Neutralizing Antibody ◽

Antibody Responses ◽

Clinical Disease ◽

High Dose ◽

Preclinical Studies ◽

Vaccine Protection ◽

Adenovirus Serotype

AbstractCoronavirus disease 2019 (COVID-19) in humans is often a clinically mild illness, but some individuals develop severe pneumonia, respiratory failure and death1–4. Studies of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in hamsters5–7 and nonhuman primates8–10 have generally reported mild clinical disease, and preclinical SARS-CoV-2 vaccine studies have demonstrated reduction of viral replication in the upper and lower respiratory tracts in nonhuman primates11–13. Here we show that high-dose intranasal SARS-CoV-2 infection in hamsters results in severe clinical disease, including high levels of virus replication in tissues, extensive pneumonia, weight loss and mortality in a subset of animals. A single immunization with an adenovirus serotype 26 vector-based vaccine expressing a stabilized SARS-CoV-2 spike protein elicited binding and neutralizing antibody responses and protected against SARS-CoV-2-induced weight loss, pneumonia and mortality. These data demonstrate vaccine protection against SARS-CoV-2 clinical disease. This model should prove useful for preclinical studies of SARS-CoV-2 vaccines, therapeutics and pathogenesis.

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Infectious RNA vaccine protects mice against chikungunya virus infection

Scientific Reports ◽

10.1038/s41598-020-78009-7 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Inga Szurgot ◽

Karl Ljungberg ◽

Beate M. Kümmerer ◽

Peter Liljeström

Keyword(s):

Chikungunya Virus ◽

Neutralizing Antibody ◽

Antibody Responses ◽

High Dose ◽

Vaccine Platform ◽

Encoding Gene ◽

Rna Replicon ◽

Nsp3 Gene

AbstractWe describe a novel vaccine platform that can generate protective immunity to chikungunya virus (CHIKV) in C57BL/6J mice after a single immunization by employing an infectious RNA (iRNA), which upon introduction into a host cell launches an infectious attenuated virus. We and others have previously reported that an engineered deletion of 183 nucleotides in the nsP3 gene attenuates chikungunya virus (CHIKV) and reduces in vivo viral replication and viremia after challenge in mice, macaques and man. Here, we demonstrated that in vitro transfection of iRNA carrying the nsP3 deletion generated infectious viruses, and after intramuscular injection, the iRNA induced robust antibody responses in mice. The iRNA was superior at eliciting binding and neutralizing antibody responses as compared to a DNA vaccine encoding the same RNA (iDNA) or a non-propagating RNA replicon (RREP) lacking the capsid encoding gene. Subsequent challenge with a high dose of CHIKV demonstrated that the antibody responses induced by this vaccine candidate protected animals from viremia. The iRNA approach constitutes a novel vaccine platform with the potential to impact the spread of CHIKV. Moreover, we believe that this approach is likely applicable also to other positive-strand viruses.

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