scholarly journals Serum and Cervicovaginal Fluid Antibody Profiling in Herpes Simplex Virus (HSV) Seronegative Recipients of the HSV529 Vaccine

2021 ◽  
Author(s):  
Kening Wang ◽  
Lesia Dropulic ◽  
Joel Bozekowski ◽  
Harlan L Pietz ◽  
Sinthujan Jegaskanda ◽  
...  
Keyword(s):  
Genital Tract ◽  
Cell Activation ◽  
Nk Cell ◽  
Neutralizing Antibody ◽  
Viral Proteins ◽  
Antibody Responses ◽  
Binding Antibody ◽  
Simplex Virus ◽  
Antibody Epitopes ◽  
Cervicovaginal Fluid

Abstract Previous HSV2 vaccines have not prevented genital herpes. Concerns have been raised about the choice of antigen, the type of antibody induced by the vaccine, and whether antibody is present in the genital tract where infection occurs. We reported results of a trial of an HSV2 replication-defective vaccine, HSV529, that induced serum neutralizing antibody responses in 78% of HSV1 -/HSV2 - vaccine recipients. Here we show that HSV1 -/HSV2 - vaccine recipients developed antibodies to epitopes of several viral proteins; however, fewer antibody epitopes were detected in vaccine recipients compared with naturally infected persons. HSV529 induced antibodies that mediated HSV2-specific NK cell activation. Depletion of gD-binding antibody from sera reduced neutralizing titers by 62% and NK cell activation by 81%. HSV2 gD antibody was detected in cervicovaginal fluid at about one-third the level of that in serum. A vaccine that induces potent serum antibodies transported to the genital tract might reduce HSV genital infection.

scholarly journals Immunogenicity of HIV-1-Based Virus-Like Particles with Increased Incorporation and Stability of Membrane-Bound Env

Vaccines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 239
Author(s):  
Christopher A. Gonelli ◽  
Hannah A. D. King ◽  
Charlene Mackenzie ◽  
Secondo Sonza ◽  
Rob J. Center ◽  
...  
Keyword(s):  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Neutralization Activity ◽  
Virus Like Particles ◽  
Antibody Isotypes ◽  
Immunodeficiency Virus ◽  
Proline Substitution ◽  
Membrane Bound ◽  
Antibody Epitopes ◽  
Hiv 1

An optimal prophylactic vaccine to prevent human immunodeficiency virus (HIV-1) transmission should elicit protective antibody responses against the HIV-1 envelope glycoprotein (Env). Replication-incompetent HIV-1 virus-like particles (VLPs) offer the opportunity to present virion-associated Env with a native-like structure during vaccination that closely resembles that encountered on infectious virus. Here, we optimized the incorporation of Env into previously designed mature-form VLPs (mVLPs) and assessed their immunogenicity in mice. The incorporation of Env into mVLPs was increased by replacing the Env transmembrane and cytoplasmic tail domains with those of influenza haemagglutinin (HA-TMCT). Furthermore, Env was stabilized on the VLP surface by introducing an interchain disulfide and proline substitution (SOSIP) mutations typically employed to stabilize soluble Env trimers. The resulting mVLPs efficiently presented neutralizing antibody epitopes while minimizing exposure of non-neutralizing antibody sites. Vaccination of mice with mVLPs elicited a broader range of Env-specific antibody isotypes than Env presented on immature VLPs or extracellular vesicles. The mVLPs bearing HA-TMCT-modified Env consistently induced anti-Env antibody responses that mediated modest neutralization activity. These mVLPs are potentially useful immunogens for eliciting neutralizing antibody responses that target native Env epitopes on infectious HIV-1 virions.

scholarly journals Antibody Responses with Fc-Mediated Functions after Vaccination of HIV-Infected Subjects with Trivalent Influenza Vaccine

2016 ◽  
Vol 90 (12) ◽  
pp. 5724-5734 ◽  
Author(s):  
Anne B. Kristensen ◽  
William N. Lay ◽  
Fernanda Ana-Sosa-Batiz ◽  
Hillary A. Vanderven ◽  
Vijaya Madhavi ◽  
...  
Keyword(s):  
Influenza Vaccine ◽  
Cell Activation ◽  
Seasonal Influenza ◽  
Nk Cell ◽  
Antibody Responses ◽  
Hiv Positive ◽  
Binding Assays ◽  
Positive Group ◽  
Hiv Negative

ABSTRACTThis study seeks to assess the ability of seasonal trivalent inactivated influenza vaccine (TIV) to induce nonneutralizing antibodies (Abs) with Fc-mediated functions in HIV-uninfected and HIV-infected subjects. Functional influenza-specific Ab responses were studied in 30 HIV-negative and 27 HIV-positive subjects immunized against seasonal influenza. All 57 subjects received the 2015 TIV. Fc-mediated antihemagglutinin (anti-HA) Ab activity was measured in plasma before and 4 weeks after vaccination using Fc-receptor-binding assays, NK cell activation assays, and phagocytosis assays. At baseline, the HIV-positive group had detectable but reduced functional Ab responses to both vaccine and nonvaccine influenza antigens. TIV enhanced Fc-mediated Ab responses in both HIV-positive and HIV-negative groups. A larger rise was generally observed in the HIV-positive group, such that there was no difference in functional Ab responses between the two groups after vaccination. The 2015 TIV enhanced functional influenza-specific Ab responses in both HIV-negative and HIV-positive subjects to a range of influenza HA proteins. The increase in functional Ab responses in the HIV-positive group supports recommendations to immunize this at-risk group.IMPORTANCEInfection with HIV is associated with increasing disease severity following influenza infections, and annual influenza vaccinations are recommended for this target group. However, HIV-infected individuals respond relatively poorly to vaccination compared to healthy individuals, particularly if immunodeficient. There is therefore a need to increase our understanding of immunity to influenza in the context of underlying HIV infection. While antibodies can mediate direct virus neutralization, interactions with cellular Fc receptors may be important for anti-influenza immunityin vivoby facilitating antibody-dependent cellular cytotoxicity (ADCC) and/or antibody-dependent phagocytosis (ADP). The ability of seasonal influenza vaccines to induce antibody responses with potent Fc-mediated antiviral activity is currently unclear. Probing the ADCC and ADP responses to influenza vaccination has provided important new information in the quest to improve immunity to influenza.

scholarly journals Suppression of the Interferon-Mediated Innate Immune Response by Pseudorabies Virus

2006 ◽  
Vol 80 (13) ◽  
pp. 6345-6356 ◽  
Author(s):  
Alla Brukman ◽  
L. W. Enquist
Keyword(s):  
Immune Response ◽  
Cell Activation ◽  
Pseudorabies Virus ◽  
Nk Cell ◽  
Innate Immune ◽  
Human Pathogens ◽  
Wild Type ◽  
Varicella Zoster ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACT Pseudorabies virus (PRV) is an alphaherpesvirus related to the human pathogens herpes simplex virus type 1 (HSV-1) and varicella-zoster virus. PRV is capable of infecting and killing a wide variety of mammals. How it avoids innate immune defenses in so many hosts is not understood. While the anti-interferon (IFN) strategies of HSV-1 have been studied, little is known about how PRV evades the IFN-mediated immune response. In this study, we determined if wild-type PRV infection can overcome the establishment of a beta interferon (IFN-β)-induced antiviral state in primary rat fibroblasts. Using microarray technology, we found that the expression of a subset of genes normally induced by IFN-β in these cells was not induced when the cells were simultaneously infected with a wild-type PRV strain. Expression of transcripts associated with major histocompatibility complex class I antigen presentation and NK cell activation was reduced, while transcripts associated with inflammation either were unaffected or were induced by viral infection. This suppression of IFN-stimulated gene expression occurred because IFN signal transduction, in particular the phosphorylation of STAT1, became less effective in PRV-infected cells. At least one virion-associated protein is involved in inhibition of STAT1 tyrosine phosphorylation. This ability to disarm the IFN-β response offers an explanation for the uniform lethality of virulent PRV infection of nonnatural hosts.

scholarly journals Serum Immune Responses to the Proteins of Porcine Reproductive and Respiratory Syndrome (PRRS) Virus

1994 ◽  
Vol 6 (4) ◽  
pp. 410-415 ◽  
Author(s):  
Eric A. Nelson ◽  
Jane Christopher-Hennings ◽  
David A. Benfield
Keyword(s):  
Immune Responses ◽  
Indirect Immunofluorescence ◽  
Neutralizing Antibodies ◽  
Virus Isolate ◽  
Neutralizing Antibody ◽  
Viral Proteins ◽  
Antibody Responses ◽  
Virus Neutralization ◽  
Respiratory Syndrome Virus ◽  
Prrs Virus

The antibody responses of pigs to porcine reproductive and respiratory syndrome virus (isolate VR-2332) were evaluated by indirect immunofluorescence, virus neutralization, and immunoblotting. All pigs in each group were positive by indirect immunofluorescence 14-21 days postexposure (DPE), and antibodies to specific viral proteins (15, 19 or 26 kD) were initially demonstrated by immunoblotting at 7–21 days DPE. Neutralizing antibodies were detected in only 2 pigs that were inoculated intranasally and given additional parenteral injections with adjuvant. These antibodies appeared much later, 51–70 DPE, than did antibodies detected by indirect immunofluorescence. The titer of the neutralizing antibodies increased until 127 DPE, after which the titers decreased, and 1 animal became seronegative for neutralizing antibody by 262 DPE.

scholarly journals Expansion of SARS-CoV-2-specific Antibody-secreting Cells and Generation of Neutralizing Antibodies in Hospitalized COVID-19 Patients

2020 ◽  
Author(s):  
Renata Varnaitė ◽  
Marina García ◽  
Hedvig Glans ◽  
Kimia T. Maleki ◽  
John Tyler Sandberg ◽  
...  
Keyword(s):  
B Cell ◽  
Specific Antibody ◽  
Neutralizing Antibodies ◽  
Cell Activation ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
B Cell Activation ◽  
Immunological Parameters ◽  
Antibody Secreting Cell ◽  
Antibody Levels

AbstractCoronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 and has since become a global pandemic. Pathogen-specific antibodies are typically a major predictor of protective immunity, yet B cell and antibody responses during COVID-19 are not fully understood. Here, we analyzed antibody-secreting cell (ASC) and antibody responses in twenty hospitalized COVID-19 patients. The patients exhibited typical symptoms of COVID-19, and presented with reduced lymphocyte numbers and increased T cell and B cell activation. Importantly, we detected an expansion of SARS-CoV-2 nucleocapsid protein-specific ASCs in all twenty COVID-19 patients using a multicolor FluoroSpot assay. Out of the 20 patients, 16 had developed SARS-CoV-2-neutralizing antibodies by the time of inclusion in the study. SARS-CoV-2-specific IgA, IgG and IgM antibody levels positively correlated with SARS-CoV-2-neutralizing antibody titers, suggesting that SARS-CoV-2-specific antibody levels may reflect the titers of neutralizing antibodies in COVID-19 patients during the acute phase of infection. Lastly, we showed that interleukin 6 (IL-6) and C-reactive protein (CRP) concentrations were higher in serum of patients who were hospitalized for longer, supporting the recent observations that IL-6 and CRP could be used to predict COVID-19 severity. Altogether, this study constitutes a detailed description of clinical and immunological parameters in twenty COVID-19 patients, with a focus on B cell and antibody responses, and provides tools to study immune responses to SARS-CoV-2 infection and vaccination.

scholarly journals Sex disparities and neutralizing antibody durability to SARS-CoV-2 infection in convalescent individuals

2021 ◽  
Author(s):  
Alena J. Markmann ◽  
Natasa Giallourou ◽  
D. Ryan Bhowmik ◽  
Yixuan J. Hou ◽  
Aaron Lerner ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Human Antibody ◽  
Antibody Titers ◽  
Sex Disparities ◽  
Binding Antibody ◽  
Male Sex ◽  
Antibody Levels ◽  
First Time

AbstractThe coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) has now caused over 2 million deaths worldwide and continues to expand. Currently, much is unknown about functionally neutralizing human antibody responses and durability to SARS-CoV-2. Using convalescent sera collected from 101 COVID-19 recovered individuals 21-212 days after symptom onset with forty-eight additional longitudinal samples, we measured functionality and durability of serum antibodies. We also evaluated associations between individual demographic and clinical parameters with functional neutralizing antibody responses to COVID-19. We found robust antibody durability out to six months, as well as significant positive associations with the magnitude of the neutralizing antibody response and male sex. We also show that SARS-CoV-2 convalescent neutralizing antibodies are higher in individuals with cardio-metabolic comorbidities.SignificanceIn this study we found that neutralizing antibody responses in COVID-19 convalescent individuals vary in magnitude but are durable and correlate well with RBD Ig binding antibody levels compared to other SARS-CoV-2 antigen responses. In our cohort, higher neutralizing antibody titers are independently and significantly associated with male sex compared to female sex. We also show for the first time, that higher convalescent antibody titers in male donors are associated with increased age and symptom grade. Furthermore, cardio-metabolic co-morbidities are associated with higher antibody titers independently of sex. Here, we present an in-depth evaluation of serologic, demographic, and clinical correlates of functional antibody responses and durability to SARS-CoV-2.

scholarly journals Durability of antibody responses elicited by a single dose of Ad26.COV2.S and substantial increase following late boosting

2021 ◽  
Author(s):  
Jerald Sadoff ◽  
Mathieu Le Gars ◽  
Vicky Cardenas ◽  
Georgi Shukarev ◽  
Nathalie Vaissiere ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Single Dose ◽  
Booster Dose ◽  
Age Groups ◽  
Neutralizing Antibody ◽  
Primary Vaccination ◽  
Antibody Responses ◽  
Binding Antibody ◽  
Antibody Levels ◽  
The Impact

AbstractBackgroundWe evaluated the durability of SARS-CoV-2 antibody levels elicited by the single dose Janssen COVID-19 vaccine, Ad26.COV2.S, and the impact on antibody responses of boosting with Ad26.COV2.S after 6 months in clinical trial participants.MethodsSpike-binding antibody and SARS-CoV-2 neutralizing antibody levels elicited by a single-dose Ad26.COV2.S (5×1010 viral particles [vp]) primary regimen and booster doses (5×1010 vp and 1.25×1010 vp) were assessed by ELISA and wild-type VNA in sera from participants in a Phase 1/2a clinical trial (Cohort 1a, 18–55 years old, N=25; Cohort 2a, 18–55 years old boosted at 6 months, N=17; Cohort 3, ≥65 years old, N=22) and a Phase 2 clinical trial (18–55 and ≥65-year old participants boosted at 6 months, total N=73). Neutralizing antibody levels were determined approximately 8 months after the primary vaccination in participants aged 18–55 years and approximately 9 months in participants aged ≥65 years. Binding antibody levels were evaluated 6 months after primary vaccination and 7- and 28-days after booster doses in both age groups.ResultsA single dose of Ad26.COV2.S elicited neutralizing antibodies that remained largely stable for approximately 8–9 months and binding antibodies that remained stable for at least 6 months irrespective of age group. A 5×1010 vp booster dose at 6 months post prime vaccination in 18–55-year-old adults elicited a steep and robust 9-fold increase at Day 7 post boost compared to Day 29 levels following the initial immunization. A lower booster dose of 1.25×1010 vp at 6 months in adults 18–55 and ≥65 years of age also elicited a rapid and high increase of 6–7.7 fold at Day 28 post boost compared to Day 29 levels following the initial immunization, with similar magnitude of post-boost responses in both age groups.ConclusionsA single dose of Ad26.COV2.S, which demonstrated protection in a Phase 3 efficacy trial, elicited durable neutralizing and binding antibodies for at least 8 and 6 months, respectively, in adults >18 years of age at levels similar to Day 29 responses. A 5×1010 vp or 1.25×1010 vp booster dose at 6 months elicited rapid and robust increases in spike binding antibody levels. The anamnestic responses after booster immunization imply robust immune memory elicited by single-dose Ad26.COV2.S.

scholarly journals Development of a high-throughput bead based assay system to measure HIV-1 specific immune signatures in clinical samples

2017 ◽  
Author(s):  
Thomas Liechti ◽  
Claus Kadelka ◽  
Hanna Ebner ◽  
Nikolas Friedrich ◽  
Roger D. Kouyos ◽  
...  
Keyword(s):  
High Throughput ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Assay System ◽  
Clinical Samples ◽  
Correlates Of Protection ◽  
Technical Advances ◽  
Broadly Neutralizing Antibody ◽  
Binding Antibody ◽  
Hiv 1

AbstractThe monitoring and assessment of a broadly neutralizing antibody (bnAb) based HIV-1 vaccine require detailed measurements of HIV-1 binding antibody responses to support the detection of correlates of protection. Here we describe the development of a flexible, high-throughput microsphere based multiplex assay system that allows monitoring complex binding antibody signatures. Studying a panel of 13 HIV-1 antigens in a parallel assessment of different IgG subclasses (IgG1, IgG2 and IgG3) we demonstrate the potential of our strategy. The technical advances we describe include means to improve antigen reactivity using directed neutravidin-biotin immobilization of antigens and biotin saturation to reduce background. A particular emphasis of our study was to provide tools for the assessment of reproducibility and stability of the assay system and strategies to control for variations allowing the application in high-throughput assays, where reliability of single measurements needs to be guaranteed.

scholarly journals Binding and Neutralizing Antibody Responses to SARS-CoV-2 in Infants and Young Children Exceed Those in Adults

2021 ◽  
Author(s):  
Ruth A. Karron ◽  
Maria Garcia Quesada ◽  
Elizabeth A. Schappell ◽  
Stephen D. Schmidt ◽  
Maria Deloria Knoll ◽  
...  
Keyword(s):  
Young Children ◽  
Immune Responses ◽  
Receptor Binding ◽  
Neutralizing Antibody ◽  
Binding Domain ◽  
Antibody Responses ◽  
Receptor Binding Domain ◽  
Binding Antibody ◽  
Infants And Young Children

SARS-CoV-2 infections are frequently milder in children than adults, suggesting that immune responses may vary with age. However, information is limited regarding SARS-CoV-2 immune responses in young children. We compared Receptor Binding Domain binding antibody (RBDAb) and SARS-CoV-2 neutralizing antibody (neutAb) in children aged 0-4 years, 5-17 years, and in adults aged 18-62 years in a SARS-CoV-2 household study. Among 55 participants seropositive at enrollment, children aged 0-4 years had >10-fold higher RBDAb titers than adults (373 vs.35, P<0.0001), and the highest RBDAb titers in 11/12 households with seropositive children and adults. Children aged 0-4 years had 2-fold higher neutAb than adults, resulting in higher binding to neutralizing (B/N)Ab ratios compared to adults (1.9 vs. 0.4 for ID50, P=0.0002). Findings suggest that young children mount robust antibody responses to SARS-CoV-2 following community infections. Additionally, these results support using neutAb to measure the immunogenicity of COVID-19 vaccines in children aged 0-4 years.

scholarly journals Effects of Acute and Chronic Murine Norovirus Infections on Immune Responses and Recovery from Friend Retrovirus Infection

2009 ◽  
Vol 83 (24) ◽  
pp. 13037-13041 ◽  
Author(s):  
Christoph G. Ammann ◽  
Ronald J. Messer ◽  
Kimberly Varvel ◽  
Blair L. DeBuysscher ◽  
Rachel A. LaCasse ◽  
...  
Keyword(s):  
Immune Responses ◽  
Nk Cell ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Murine Norovirus ◽  
Friend Virus ◽  
Chronic Infections ◽  
Cell Responses ◽  
Retrovirus Infection

ABSTRACT Murine norovirus (MNV) is a highly infectious but generally nonpathogenic agent that is commonly found in research mouse colonies in both North America and Europe. In the present study, the effects of acute and chronic infections with MNV on immune responses and recovery from concurrent Friend virus (FV) infections were investigated. No significant differences in T-cell or NK-cell responses, FV-neutralizing antibody responses, or long-term recovery from FV infection were observed. We conclude that concurrent MNV infections had no major impacts on FV infections.

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