scholarly journals A New SARS CoV-2 Dual Purpose Serology Test: Highly Accurate Infection Tracing and Neutralizing Antibody Response Detection

2021 ◽  
Author(s):  
Sean C. Taylor ◽  
Beth Hurst ◽  
Carmen L. Charlton ◽  
Ashley Bailey ◽  
Jamil N. Kanji ◽  
...  
Keyword(s):  
Neutralizing Antibody ◽  
Live Cell ◽  
Dual Purpose ◽  
Protein Receptor ◽  
Serology Test ◽  
Response Detection ◽  
High Throughput Assay ◽  
Improved Accuracy ◽  
Antibody Function ◽  
Combined Data

Many SARS CoV-2 serology tests have proven to be less accurate than expected and do not assess antibody function as neutralizing, correlating with protection from reinfection. A new assay technology measuring the interaction of purified SARS CoV-2 spike protein receptor binding domain (RBD) with the extracellular domain of the human ACE2 receptor detects these important antibodies. This cPassTM surrogate virus neutralization test (sVNT) when compared directly with eight SARS CoV-2 IgG serology and two live cell neutralization tests gives similar or improved accuracy for qualitative delineation between positive and negative individuals in a fast, scalable and high throughput assay. The combined data support cPassTM sVNT as a tool for highly accurate SARS CoV-2 immunity surveillance of infected/recovered and/or vaccinated individuals, as well as drug and convalescent donor screening. The data also prevue a novel application for cPassTM sVNT in calibrating the stringency of live cell neutralization tests and its use in longitudinal testing of recovered and/or vaccinated patients.

scholarly journals Preservation of neutralizing antibody function in COVID-19 convalescent plasma treated using a riboflavin and ultraviolet light-based pathogen reduction technology

2021 ◽  
Author(s):  
Susan Yonemura ◽  
Lindsay Hartson ◽  
Taru Dutt ◽  
Marcela Henao-Tamayo ◽  
Raymond Goodrich ◽  
...  
Keyword(s):  
Ultraviolet Light ◽  
Therapeutic Option ◽  
Transmitted Disease ◽  
Coagulation Factor ◽  
Neutralizing Antibody ◽  
Coagulation Factors ◽  
Post Treatment ◽  
Protein Receptor ◽  
Pathogen Reduction ◽  
Antibody Function

AbstractBackground and ObjectiveConvalescent plasma (CP) has been embraced as a safe therapeutic option for coronavirus disease 2019 (COVID-19) while other treatments are developed. However, transfusion-transmitted disease is a risk, particularly in regions with high endemic prevalence of transfusion-transmissible diseases. Pathogen reduction can mitigate this risk; thus, the objective of this study was to evaluate the effect of riboflavin and ultraviolet light (R+UV) pathogen reduction technology on the functional properties of CCP.Materials and MethodsCCP units (n = 6) from recovered COVID-19 research donors were treated with R+UV. Pre- and post-treatment samples were tested for coagulation factor and immunoglobulin retention. Antibody binding to spike protein receptor binding domain (RBD), S1, and S2 epitopes of SARS-CoV-2 was assessed by ELISA.Neutralizing antibody (nAb) function was assessed by pseudovirus reporter viral particle neutralization (RVPN) assay and plaque reduction neutralization test (PRNT).ResultsMean retention of coagulation factors was ≥ 70% while retention of immunoglobulins was 100%. Starting nAb titers were low, but PRNT50 titers did not differ between pre- and post-treatment samples. No statistically significant differences were detected in levels of IgG (P ≥ 0.3665) and IgM (P ≥ 0.1208) antibodies to RBD, S1, and S2 proteins before and after treatment.ConclusionR+UV PRT effects on coagulation factors were similar to previous reports, but no significant effects were observed on immunoglobulin concentration and antibody function. SARS-CoV-2 nAb function in COVID-19 convalescent plasma is conserved following R+UV PRT treatment.

Association Study of Fecundity Gene BMPR1B with Prolificacy in Surti Goats under Farm and Field Condition

2019 ◽  
Vol 14 (04) ◽  
Author(s):  
N. S. Dangar ◽  
G. M. Pandya ◽  
U. V. Ramani ◽  
Y. D. Padheriya ◽  
T. Sangma ◽  
...  
Keyword(s):  
Litter Size ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Pcr Primers ◽  
Dual Purpose ◽  
Protein Receptor ◽  
Morphogenetic Protein ◽  
Pcr Rflp ◽  
Base Size ◽  
Mutation Information

The Surti is a dual purpose goat breed of Gujarat. The bone morphogenetic protein receptor type 1B (BMPR1B) gene of transforming growth factor beta (TGF-β) superfamily ligands is playing a role in ovulation as well as litter size. Mutation in Exon-6 region of BMPR1B gene with base size 190 bp reported increasing litter size. Based on the known mutation information in goat and sheep, PCR primers were designed to screen polymorphism in total 100 Surti goats, 50 Surti goats from University Farm, Navsari and 50 Surti goats from field units of Southern part of Gujarat. During PCR-RFLP study no polymorphic sites were found for Exon-6 region of BMPR1B on Surti goats. Moreover, the twinning rate was 10% in first parity and higher in subsequent second (62.5%) and third (76.8%) parties.

scholarly journals Combining a Fusion Inhibitory Peptide Targeting the MERS-CoV S2 Protein HR1 Domain and a Neutralizing Antibody Specific for the S1 Protein Receptor-Binding Domain (RBD) Showed Potent Synergism against Pseudotyped MERS-CoV with or without Mutations in RBD

Viruses ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 31 ◽  
Author(s):  
Cong Wang ◽  
Chen Hua ◽  
Shuai Xia ◽  
Weihua Li ◽  
Lu Lu ◽  
...  
Keyword(s):  
Receptor Binding ◽  
Neutralizing Antibody ◽  
Binding Domain ◽  
Spike Protein ◽  
Receptor Binding Domain ◽  
Inhibitory Peptide ◽  
Protein Receptor ◽  
Neutralizing Monoclonal Antibody ◽  
Peptide Targeting ◽  
Combinatorial Strategy

Middle East respiratory syndrome coronavirus (MERS-CoV) has continuously posed a threat to public health worldwide, yet no therapeutics or vaccines are currently available to prevent or treat MERS-CoV infection. We previously identified a fusion inhibitory peptide (HR2P-M2) targeting the MERS-CoV S2 protein HR1 domain and a highly potent neutralizing monoclonal antibody (m336) specific to the S1 spike protein receptor-binding domain (RBD). However, m336 was found to have reduced efficacy against MERS-CoV strains with mutations in RBD, and HR2P-M2 showed low potency, thus limiting the clinical application of each when administered separately. However, we herein report that the combination of m336 and HR2P-M2 exhibited potent synergism in inhibiting MERS-CoV S protein-mediated cell–cell fusion and infection by MERS-CoV pseudoviruses with or without mutations in the RBD, resulting in the enhancement of antiviral activity in contrast to either one administered alone. Thus, this combinatorial strategy could be used in clinics for the urgent treatment of MERS-CoV-infected patients.

scholarly journals Statistical Approach To Estimate Vaccinia-Specific Neutralizing Antibody Titers Using a High-Throughput Assay

2009 ◽  
Vol 16 (8) ◽  
pp. 1105-1112 ◽  
Author(s):  
Richard Kennedy ◽  
V. Shane Pankratz ◽  
Eric Swanson ◽  
David Watson ◽  
Hana Golding ◽  
...  
Keyword(s):  
Immune Responses ◽  
Vaccinia Virus ◽  
High Throughput ◽  
Large Scale ◽  
Statistical Approach ◽  
Neutralizing Antibody ◽  
Neutralization Assay ◽  
Virus Neutralization Assay ◽  
Antibody Titers ◽  
High Throughput Assay

ABSTRACT Because of the bioterrorism threat posed by agents such as variola virus, considerable time, resources, and effort have been devoted to biodefense preparation. One avenue of this research has been the development of rapid, sensitive, high-throughput assays to validate immune responses to poxviruses. Here we describe the adaptation of a β-galactosidase reporter-based vaccinia virus neutralization assay to large-scale use in a study that included over 1,000 subjects. We also describe the statistical methods involved in analyzing the large quantity of data generated. The assay and its associated methods should prove useful tools in monitoring immune responses to next-generation smallpox vaccines, studying poxvirus immunity, and evaluating therapeutic agents such as vaccinia virus immune globulin.

scholarly journals Adjuvanting a subunit SARS-CoV-2 nanoparticle vaccine to induce protective immunity in non-human primates

2021 ◽  
Author(s):  
Prabhu S. Arunachalam ◽  
Alexandra C. Walls ◽  
Nadia Golden ◽  
Caroline Atyeo ◽  
Stephanie Fischinger ◽  
...  
Keyword(s):  
Neutralizing Antibody ◽  
Alpha Tocopherol ◽  
Water Emulsion ◽  
Live Virus ◽  
Protein Receptor ◽  
Oil In Water ◽  
A Subunit ◽  
Highly Correlated ◽  
Oil In Water Emulsion ◽  
Protection Against Infection

AbstractThe development of a portfolio of SARS-CoV-2 vaccines to vaccinate the global population remains an urgent public health imperative. Here, we demonstrate the capacity of a subunit vaccine under clinical development, comprising the SARS-CoV-2 Spike protein receptor binding domain displayed on a two-component protein nanoparticle (RBD-NP), to stimulate robust and durable neutralizing antibody (nAb) responses and protection against SARS-CoV-2 in non-human primates. We evaluated five different adjuvants combined with RBD-NP including Essai O/W 1849101, a squalene-in-water emulsion; AS03, an alpha-tocopherol-containing squalene-based oil-in-water emulsion used in pandemic influenza vaccines; AS37, a TLR-7 agonist adsorbed to Alum; CpG 1018-Alum (CpG-Alum), a TLR-9 agonist formulated in Alum; or Alum, the most widely used adjuvant. All five adjuvants induced substantial nAb and CD4 T cell responses after two consecutive immunizations. Durable nAb responses were evaluated for RBD-NP/AS03 immunization and the live-virus nAb response was durably maintained up to 154 days post-vaccination. AS03, CpG-Alum, AS37 and Alum groups conferred significant protection against SARS-CoV-2 infection in the pharynges, nares and in the bronchoalveolar lavage. The nAb titers were highly correlated with protection against infection. Furthermore, RBD-NP when used in conjunction with AS03 was as potent as the prefusion stabilized Spike immunogen, HexaPro. Taken together, these data highlight the efficacy of the RBD-NP formulated with clinically relevant adjuvants in promoting robust immunity against SARS-CoV-2 in non-human primates.

scholarly journals Polymersomes decorated with SARS-CoV-2 spike protein receptor binding domain elicit robust humoral and cellular immunity

2021 ◽  
Author(s):  
Lisa R Volpatti ◽  
Rachel P Wallace ◽  
Shijie Cao ◽  
Michal Raczy ◽  
Ruyi Wang ◽  
...  
Keyword(s):  
T Cell ◽  
Antibody Response ◽  
Receptor Binding ◽  
Neutralizing Antibody ◽  
Binding Domain ◽  
Spike Protein ◽  
Receptor Binding Domain ◽  
Vaccination Site ◽  
Monophosphoryl Lipid A ◽  
Protein Receptor

A diverse portfolio of SARS-CoV-2 vaccine candidates is needed to combat the evolving COVID-19 pandemic. Here, we developed a subunit nanovaccine by conjugating SARS-CoV-2 Spike protein receptor binding domain (RBD) to the surface of oxidation-sensitive polymersomes. We evaluated the humoral and cellular responses of mice immunized with these surface-decorated polymersomes (RBDsurf) compared to RBD-encapsulated polymersomes (RBDencap) and unformulated RBD (RBDfree), using monophosphoryl lipid A-encapsulated polymersomes (MPLA PS) as an adjuvant. While all three groups produced high titers of RBD-specific IgG, only RBDsurf elicited a neutralizing antibody response to SARS-CoV-2 comparable to that of human convalescent plasma. Moreover, RBDsurf was the only group to significantly increase the proportion of RBD-specific germinal center B cells in the vaccination-site draining lymph nodes. Both RBDsurf and RBDencap drove similarly robust CD4+ and CD8+ T cell responses that produced multiple Th1-type cytokines. We conclude that multivalent surface display of Spike RBD on polymersomes promotes a potent neutralizing antibody response to SARS-CoV-2, while both antigen formulations promote robust T cell immunity.

scholarly journals A high-throughput neutralizing antibody assay for COVID-19 diagnosis and vaccine evaluation

2020 ◽  
Author(s):  
Antonio E. Muruato ◽  
Camila R. Fontes-Garfias ◽  
Ping Ren ◽  
Mariano A. Garcia-Blanco ◽  
Vineet D. Menachery ◽  
...  
Keyword(s):  
High Throughput ◽  
Gold Standard ◽  
Neutralizing Antibodies ◽  
Vaccine Development ◽  
Neutralizing Antibody ◽  
Neutralization Assay ◽  
Antibody Assay ◽  
Plasma Therapy ◽  
High Throughput Assay ◽  
Key Parameter

AbstractVirus neutralization remains the gold standard for determining antibody efficacy. Therefore, a high-throughput assay to measure SARS-CoV-2 neutralizing antibodies is urgently needed for COVID-19 serodiagnosis, convalescent plasma therapy, and vaccine development. Here we report on a fluorescence-based SARS-CoV-2 neutralization assay that detects SARS-CoV-2 neutralizing antibodies in COVID-19 patient specimens and yields comparable results to plaque reduction neutralizing assay, the gold standard of serological testing. Our approach offers a rapid platform that can be scaled to screen people for antibody protection from COVID-19, a key parameter necessary to safely reopen local communities.

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