ST109 Antigenic specificity and neutralizing activity of antibody responses elicited by different gp120/mAb immune complex vaccines

2013 ◽  
Vol 62 ◽  
pp. S68
Author(s):  
Rajnish Kumar ◽  
Michael Tuen ◽  
Catarina Hioe
Keyword(s):  
Immune Complex ◽  
Antibody Responses ◽  
Antigenic Specificity ◽  
Neutralizing Activity

scholarly journals The use of immune complex vaccines to enhance antibody responses against neutralizing epitopes on HIV-1 envelope gp120

Vaccine ◽  
2009 ◽  
Vol 28 (2) ◽  
pp. 352-360 ◽  
Author(s):  
Catarina E. Hioe ◽  
Maria Luisa Visciano ◽  
Rajnish Kumar ◽  
Jianping Liu ◽  
Ethan A. Mack ◽  
...  
Keyword(s):  
Immune Complex ◽  
Antibody Responses ◽  
Hiv 1 ◽  
Envelope Gp120 ◽  
Neutralizing Epitopes

PATHOGENESIS OF IMMUNE COMPLEX GLOMERULONEPHRITIS OF NEW ZEALAND MICE

1971 ◽  
Vol 134 (3) ◽  
pp. 65-71 ◽  
Author(s):  
Frank J. Dixon ◽  
Michael B. A. Oldstone ◽  
Giorgio Tonietti
Keyword(s):  
New Zealand ◽  
Immune Complex ◽  
Antibody Formation ◽  
Antinuclear Antibody ◽  
Viral Infections ◽  
Antibody Responses ◽  
Viral Antigens ◽  
Chronic Viral Infections ◽  
Nuclear Antigens ◽  
Antigen Antibody

Observations based on elution of IgG from nephritic kidneys of NZ mice and absorption of the eluted IgG with selected antigens indicate that their immune complex nephritis involves at least two kinds of antigen-antibody complexes. Antibodies reactive with nuclear antigens account for nearly half of the IgG eluted from the kidneys while antibodies reactive with Gross viral antigens make up a significant but lesser amount. Superimposed chronic viral infections affect the nephritis of NZ mice in different ways. LCM and polyoma infections hasten and intensify the antinuclear antibody responses and glomerulonephritis of these mice while LDV infection appears to protect against both antinuclear antibody formation and development of nephritis.

scholarly journals COMPARATIVE ANALYSIS OF ANTIBODY RESPONSES FROM COVID-19 CONVALESCENTS RECEIVING VARIOUS VACCINES REVEALS CONSISTENT HIGH NEUTRALIZING ACTIVITY FOR SARS-CoV-2 VARIANT OF CONCERN OMICRON.

2021 ◽  
Author(s):  
Daniele Franchini Focosi ◽  
Massimo Franchini ◽  
Michael J Joyner ◽  
Arturo Casadevall
Keyword(s):  
Monoclonal Antibodies ◽  
Comparative Analysis ◽  
Antibody Responses ◽  
The Novel ◽  
Early Disease ◽  
Systematic Analysis ◽  
Neutralizing Activity ◽  
Continue Study ◽  
Lessons Learnt ◽  
Disease Stages

The novel SARS-CoV-2 Omicron variant of concern (VOCs), with its escape from unboosted vaccines and monoclonal antibodies, is demanding for a return to COVID19 convalescent plasma therapies. Lessons learnt from previous usage of CCP suggests focusing on outpatients and using high nAb-titer units in early disease stages. In this systematic analysis, we show that CCP from unvaccinated donors is not effective against Omicron, while CCP from vaccinees convalescents from previous VOCs or third-dose uninfected vaccinees is likely to remain effective against Omicron. countries. CCP remains the only antibody-based therapy that keeps up with the variants and provides an effective tool to combat the emergence of variants that defeat monoclonal antibodies. Consequently, there is a need for continue study of the variables that determine CCP efficacy.

scholarly journals SARS-CoV-2 spike conformation determines plasma neutralizing activity

2021 ◽  
Author(s):  
John E Bowen ◽  
Alexandra C Walls ◽  
Anshu Joshi ◽  
Kaitlin R Sprouse ◽  
Cameron Stewart ◽  
...  
Keyword(s):  
Antibody Responses ◽  
Specific Antibodies ◽  
Neutralizing Activity ◽  
Cross Neutralization ◽  
Almost All ◽  
Physical Stabilization ◽  
Globally Distributed

Numerous safe and effective COVID-19 vaccines have been developed that utilize various delivery technologies and engineering strategies. The influence of the SARS-CoV-2 spike (S) glycoprotein conformation on antibody responses induced by vaccination or infection in humans remains unknown. To address this question, we compared plasma antibodies elicited by six globally-distributed vaccines or infection and observed markedly higher binding titers for vaccines encoding a prefusion-stabilized S relative to other groups. Prefusion S binding titers positively correlated with plasma neutralizing activity, indicating that physical stabilization of the prefusion conformation enhances protection against SARS-CoV-2. We show that almost all plasma neutralizing activity is directed to prefusion S, in particular the S1 subunit, and that variant cross-neutralization is mediated solely by RBD-specific antibodies. Our data provide a quantitative framework for guiding future S engineering efforts to develop vaccines with higher resilience to the emergence of variants and longer durability than current technologies.

scholarly journals The plasmablast response to SARS-CoV-2 mRNA vaccination is dominated by non-neutralizing antibodies that target both the NTD and the RBD

2021 ◽  
Author(s):  
Fatima Amanat ◽  
Mahima Thapa ◽  
Tinting Lei ◽  
Shaza M. Sayed Ahmed ◽  
Daniel C. Adelsberg ◽  
...  
Keyword(s):  
Polyclonal Antibody ◽  
Neutralizing Antibodies ◽  
Polyclonal Antibodies ◽  
Natural Infection ◽  
Antibody Responses ◽  
Viral Isolate ◽  
Neutralizing Activity ◽  
Human Coronaviruses ◽  
Original Antigenic Sin ◽  
Spike Proteins

SummaryIn this study we profiled vaccine-induced polyclonal antibodies as well as plasmablast derived mAbs from subjects who received SARS-CoV-2 spike mRNA vaccine. Polyclonal antibody responses in vaccinees were robust and comparable to or exceeded those seen after natural infection. However, that the ratio of binding to neutralizing antibodies after vaccination was greater than that after natural infection and, at the monoclonal level, we found that the majority of vaccine-induced antibodies did not have neutralizing activity. We also found a co-dominance of mAbs targeting the NTD and RBD of SARS-CoV-2 spike and an original antigenic-sin like backboost to seasonal human coronaviruses OC43 and HKU1 spike proteins. Neutralizing activity of NTD mAbs but not RBD mAbs against a clinical viral isolate carrying E484K as well as extensive changes in the NTD was abolished, suggesting that a proportion of vaccine induced RBD binding antibodies may provide substantial protection against viral variants carrying E484K.

scholarly journals Asymptomatic or mild symptomatic SARS-CoV-2 infection elicits durable neutralizing antibody responses in children and adolescents

2021 ◽  
Author(s):  
Carolina Garrido ◽  
Jillian H Hurst ◽  
Cynthia G. Lorang ◽  
Jhoanna N. Aquino ◽  
Javier Rodriguez ◽  
...  
Keyword(s):  
Immune Responses ◽  
Children And Adolescents ◽  
Acute Infection ◽  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Symptomatic Infection ◽  
Neutralizing Activity ◽  
Humoral Immune ◽  
Humoral Immune Responses ◽  
Broad Array

As SARS-CoV-2 continues to spread globally, questions have emerged regarding the strength and durability of immune responses in specific populations. In this study, we evaluated humoral immune responses in 69 children and adolescents with asymptomatic or mild symptomatic SARS-CoV-2 infection. We detected robust IgM, IgG, and IgA antibody responses to a broad array of SARS-CoV-2 antigens at the time of acute infection and 2 and 4 months after acute infection in all participants. Notably, these antibody responses were associated with virus neutralizing activity that was still detectable 4 months after acute infection in 94% of children. Moreover, antibody responses and neutralizing activity in sera from children and adolescents were comparable or superior to those observed in sera from 24 adults with mild symptomatic infection. Taken together, these findings indicate children and adolescents with mild or asymptomatic SARS-CoV-2 infection generate robust and durable humoral immune responses that are likely to protect from reinfection.

Delta breakthrough infections elicit potent, broad and durable neutralizing antibody responses

2021 ◽  
Author(s):  
Alexandra C Walls ◽  
Kaitlin R Sprouse ◽  
Anshu Joshi ◽  
John E Bowen ◽  
Nicholas Franko ◽  
...  
Keyword(s):  
Neutralizing Antibody ◽  
Antibody Responses ◽  
Pandemic Preparedness ◽  
Neutralizing Activity ◽  
Comparable Magnitude

The SARS-CoV-2 Delta variant is currently responsible for most infections worldwide, including among vaccinated individuals. Although these latter infections lead to milder COVID-19 disease relative to unvaccinated subjects, the specificity and durability of antibody responses elicited by Delta breakthrough cases remain unknown. Here, we demonstrate that breakthrough infections induce serum binding and neutralizing antibody responses that are markedly more potent, durable and resilient to spike mutations observed in variants than those observed in subjects who were infected only or received only two doses of vaccine. We show that Delta breakthrough cases, subjects who were vaccinated after infection and individuals vaccinated three times (without infection) have serum neutralizing activity of comparable magnitude and breadth, indicating that multiple types of exposure or increased number of exposures to SARS-CoV-2 antigen(s) enhance antibody responses. Neutralization of SARS-CoV, however, was moderate, underscoring the importance of developing vaccines eliciting broad sarbecovirus immunity for pandemic preparedness.

scholarly journals AUTOLOGOUS IMMUNE COMPLEX NEPHRITIS INDUCED WITH RENAL TUBULAR ANTIGEN

1968 ◽  
Vol 127 (3) ◽  
pp. 555-572 ◽  
Author(s):  
Thomas S. Edgington ◽  
Richard J. Glassock ◽  
Frank J. Dixon
Keyword(s):  
Plasma Membrane ◽  
Immune Complex ◽  
Rat Kidney ◽  
Specific Antigen ◽  
Membranous Glomerulonephritis ◽  
Antigenic Specificity ◽  
Normal Rat ◽  
Renal Tubular ◽  
Capillary Walls ◽  
Experimental Allergic

The nephritogenic antigen, responsible for the immunogenic stimulus in experimental allergic glomerulonephritis induced with tubular antigen, has been identified as a renal tubular epithelial (RTE)-specific antigen and has been isolated in a relatively purified form. This antigen, RTE-α5, is a distinct and antigenically specific lipoprotein of high density which is derived primarily from the brush border of proximal convoluted tubular epthelium of the rat kidney. It has been suggested that this molecule may be a plasma membrane subunit. Immunization of rats with as little as 3 µg N of RTE-α5 in complete Freund's adjuvant has effectively induced this form of membranous glomerulonephritis. RTE-α5 is not a constituent of normal rat glomeruli; however, with the onset of autologous immune complex nephritis it is deposited in a granular fashion along glomerular capillary walls indistinguishable from the deposits of γ-globulin and complement. The antigenic specificity of this antigen and its tissue derivation has been explored, and the observations support the autologous immune complex pathogenesis of the glomerulonephritis induced in rats by immunization with renal tubular antigen.

Characterization of Chlamydia trachomatis antigens with monoclonal and polyclonal antibodies

1988 ◽  
Vol 34 (2) ◽  
pp. 141-147 ◽  
Author(s):  
Ian W. Maclean ◽  
Rosanna W. Peeling ◽  
Robert C. Brunham
Keyword(s):  
Chlamydia Trachomatis ◽  
Polyclonal Antibodies ◽  
Antigenic Specificity ◽  
Immunoblot Assay ◽  
Neutralizing Activity ◽  
Molecular Masses ◽  
Monospecific Antisera ◽  
Biologic Function

We used monoclonal antibodies (MAbs) to examine the antigenic specificity and biologic function of several Chlamydia trachomatis antigens. Thirteen distinct MAbs to eight C. trachomatis antigens were produced. Six MAbs reacted with unique epitopes on the major outer membrane protein (MOMP) and two of these had neutralizing activity. MAbs were produced to each of the chlamydial antigens with molecular masses of 10, 29, 32, 57, 60, 70, and 75 kilodaltons (kDa). These MAbs showed species and genus specificity in an immunoblot assay. None of the MAbs had neutralizing activity. The epitopes recognized on MOMP, 29-, and 10-kDa (presumably lipopolysaccharide) antigens were surface exposed. MAbs to the 75-kDa, 57-kDa, and MOMP antigens were used for immunoaffinity purification of these antigens to produce monospecific antisera in mice. With polyclonal sera, we found that the 75-kDa antigen was also immunoaccessible and that antibody to MOMP and 75-kDa antigens neutralized C. trachomatis infectivity. We conclude that, in addition to MOMP and lipopolysaccharide, antigens with molecular masses of 75 and 29 kDa are surface exposed. Antibodies to MOMP and 75-kDa antigens can neutralize the organism in vitro.

Sign in / Sign up

Export Citation Format

Share Document