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1.
PLOS Glob Public Health ; 4(9): e0003319, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39302924

RESUMO

Induction of broad, durable immune responses is a challenge in HIV vaccine development. HVTN 100 Part A administered subtype C-containing ALVAC-HIV at months 0 and 1, and ALVAC-HIV with bivalent subtype C gp120/MF59 at months 3, 6 and 12. As IgG binding antibody and T-cell responses were similar or greater at month 12.5 vs. month 6.5, but waned by month 18, we investigated vaccine-elicited immune responses after a month 30 boost in this study, HVTN 100 Part B. From 13 September 2017 to 7 August 2018, a subgroup of vaccinees was randomized to receive intramuscular injections of ALVAC+gp120/MF59 (n = 32) or gp120/MF59 alone (n = 31) and a subgroup of placebo recipients was administered placebo (n = 7) at month 30. Primary outcomes were safety, IgG binding antibodies (bAbs) to vaccine-specific and V1V2 Env proteins and vaccine-specific CD4+ T cells at month 30.5. Secondary outcomes included neutralizing and antibody dependent cellular cytotoxicity functions and durability at months 30 and 36. Both vaccine groups had an acceptable safety profile. There were no statistically significant differences in the occurrence or level of IgG bAbs between the vaccine boost groups for any vaccine-specific or V1V2 antigens. IgG responses were higher to vaccine-matched gp120 than to V1V2. The booster vaccination restored the magnitude-breadth IgG bAb response to V1V2 antigens at month 30.5. However, it rapidly waned by month 36. CD4+ T-cell response rates to the 3 vaccine-matched Env antigens for the combined vaccine groups ranged from 37% at month 30, boosted to as high as 91% at month 30.5, and waned by month 36 to as low as 44%, with no significant differences between the vaccine boost groups. Because these responses waned after 6 months, additional strategies may be needed to maintain the durability of prime-boost vaccine regimens and to generate these or other immune responses that confer protection. Trial registration: South African National Clinical Trials Register (SANCTR number: DOH-27-0215-4796) and ClinicalTrials.gov (NCT02404311).

2.
Nat Commun ; 15(1): 7954, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261482

RESUMO

In the phase 3 Coronavirus Efficacy (COVE) trial (NCT04470427), post-dose two Ancestral Spike-specific binding (bAb) and neutralizing (nAb) antibodies were shown to be correlates of risk (CoR) and of protection against Ancestral-lineage COVID-19 in SARS-CoV-2 naive participants. In the SARS-CoV-2 Omicron era, Omicron subvariants with varying degrees of immune escape now dominate, seropositivity rates are high, and booster doses are administered, raising questions on whether and how these developments affect the bAb and nAb correlates. To address these questions, we assess post-boost BA.1 Spike-specific bAbs and nAbs as CoRs and as correlates of booster efficacy in COVE. For naive individuals, bAbs and nAbs inversely correlate with Omicron COVID-19: hazard ratios (HR) per 10-fold marker increase (95% confidence interval) are 0.16 (0.03, 0.79) and 0.31 (0.10, 0.96), respectively. In non-naive individuals the analogous results are similar: 0.15 (0.04, 0.63) and 0.28 (0.07, 1.08). For naive individuals, three vs two-dose booster efficacy correlates with predicted nAb titer at exposure, with estimates -8% (-126%, 48%), 50% (25%, 67%), and 74% (49%, 87%), at 56, 251, and 891 Arbitrary Units/ml. These results support the continued use of antibody as a surrogate endpoint.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Imunização Secundária , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , COVID-19/imunologia , COVID-19/virologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Glicoproteína da Espícula de Coronavírus/imunologia , Vacina de mRNA-1273 contra 2019-nCoV/administração & dosagem , Vacina de mRNA-1273 contra 2019-nCoV/imunologia , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Feminino , Masculino , Adulto , Eficácia de Vacinas
4.
Pharmaceutics ; 16(5)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38794258

RESUMO

Monoclonal antibodies are commonly engineered with an introduction of Met428Leu and Asn434Ser, known as the LS mutation, in the fragment crystallizable region to improve pharmacokinetic profiles. The LS mutation delays antibody clearance by enhancing binding affinity to the neonatal fragment crystallizable receptor found on endothelial cells. To characterize the LS mutation for monoclonal antibodies targeting HIV, we compared pharmacokinetic parameters between parental versus LS variants for five pairs of anti-HIV immunoglobin G1 monoclonal antibodies (VRC01/LS/VRC07-523LS, 3BNC117/LS, PGDM1400/LS PGT121/LS, 10-1074/LS), analyzing data from 16 clinical trials of 583 participants without HIV. We described serum concentrations of these monoclonal antibodies following intravenous or subcutaneous administration by an open two-compartment disposition, with first-order elimination from the central compartment using non-linear mixed effects pharmacokinetic models. We compared estimated pharmacokinetic parameters using the targeted maximum likelihood estimation method, accounting for participant differences. We observed lower clearance rate, central volume, and peripheral volume of distribution for all LS variants compared to parental monoclonal antibodies. LS monoclonal antibodies showed several improvements in pharmacokinetic parameters, including increases in the elimination half-life by 2.7- to 4.1-fold, the dose-normalized area-under-the-curve by 4.1- to 9.5-fold, and the predicted concentration at 4 weeks post-administration by 3.4- to 7.6-fold. Results suggest a favorable pharmacokinetic profile of LS variants regardless of HIV epitope specificity. Insights support lower dosages and/or less frequent dosing of LS variants to achieve similar levels of antibody exposure in future clinical applications.

5.
Food Funct ; 14(20): 9287-9294, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37779467

RESUMO

Background: High dietary inflammatory index (DII®) scores, representing pro-inflammatory diets, have been associated with increased risks for numerous cancers. However, the evidence for renal cancer is limited. In the present study, we aimed to assess the association between DII and renal cancer risk in the Prostate, Lung, Colorectal, and Ovarian (PLCO) cohort. Methods: Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using a Cox proportional hazards model with adjustment for various potential confounders. Results: After a median 12.2 years of follow-up, this study recorded 443 renal cancer cases among 101 190 individuals. The DII score was positively associated with renal cancer risk in multivariable analyses. The HR in the highest DII tertile compared to the lowest tertile was 1.38 (95% CI 1.03-1.84). This was also true when DII was analyzed as a continuous variable. The HR of one-unit increment in DII for renal cancer risk was 1.07 (95% CI 1.01-1.12). Conclusion: In this large American cohort, pro-inflammatory diet, as estimated by higher DII scores, was significantly associated with a greater risk of renal cancer. Future large prospective studies are warranted to verify these preliminary findings.


Assuntos
Inflamação , Neoplasias Renais , Masculino , Humanos , Estados Unidos , Estudos Prospectivos , Fatores de Risco , Inflamação/etiologia , Dieta , Neoplasias Renais/etiologia , Neoplasias Renais/complicações
6.
Lancet HIV ; 10(10): e653-e662, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37802566

RESUMO

BACKGROUND: Preclinical and clinical studies suggest that combinations of broadly neutralising antibodies (bnAbs) targeting different HIV envelope epitopes might be required for sufficient prevention of infection. We aimed to evaluate the dual and triple anti-HIV bnAb combinations of PGDM1400 (V2 Apex), PGT121 (V3 glycan), 10-1074 (V3 glycan), and VRC07-523LS (CD4 binding site). METHODS: In this phase 1 trial (HVTN 130/HPTN 089), adults without HIV were randomly assigned (1:1:1) to three dual-bnAb treatment groups simultaneously, or the triple-bnAb group, receiving 20 mg/kg of each antibody administered intravenously at four centres in the USA. Participants received a single dose of PGT121 + VRC07-523LS (treatment one; n=6), PGDM1400 + VRC07-523LS (treatment two; n=6), or 10-1074 + VRC07-523LS (treatment three; n=6), and two doses of PGDM1400 + PGT121 + VRC07-523LS (treatment four; n=9). Primary outcomes were safety, pharmacokinetics, and neutralising activity. Safety was determined by monitoring for 60 min after infusions and throughout the study by collecting laboratory assessments (ie, blood count, chemistry, urinalysis, and HIV), and solicited and unsolicited adverse events (via case report forms and participant diaries). Serum concentrations of each bnAb were measured by binding antibody assays on days 0, 3, 6, 14, 28, 56, 112, 168, 224, 280, and 336, and by serum neutralisation titres against Env-pseudotyped viruses on days 0, 3, 28, 56, and 112. Pharmacokinetic parameters were estimated by use of two-compartment population pharmacokinetic models; combination bnAb neutralisation titres were directly measured and assessed with different interaction models. This trial is registered with ClinicalTrials.gov, NCT03928821, and has been completed. FINDINGS: 27 participants were enrolled from July 31, to Dec 20, 2019. The median age was 26 years (range 19-50), 16 (58%) of 27 participants were assigned female sex at birth, and 24 (89%) participants were non-Hispanic White. Infusions were safe and well tolerated. There were no statistically significant differences in pharmacokinetic patterns between the dual and triple combinations of PGT121, PGDM1400, and VRC07-523LS. The median estimated elimination half-lives of PGT121, PGDM1400, 10-1074, and VRC07-523LS were 32·2, 25·4, 27·5, and 52·9 days, respectively. Neutralisation coverage against a panel of 12 viruses was greater in the triple-bnAb versus dual-bnAb groups: area under the magnitude-breadth curve at day 28 was 3·1, 2·9, 3·0, and 3·4 for treatments one to four, respectively. The Bliss-Hill multiplicative interaction model, which assumes complementary neutralisation with no antagonism or synergism among the bnAbs, best described combination bnAb titres in the dual-bnAb and triple-bnAb groups. INTERPRETATION: No pharmacokinetic interactions among the bnAbs and no loss of complementary neutralisation were observed in the dual and triple combinations. This study lays the foundation for designing future combination bnAb HIV prevention efficacy trials. FUNDING: US National Institute of Allergy and Infectious Diseases, US National Institute on Drug Abuse, US National Institute of Mental Health, and the Eunice Kennedy Shriver National Institute of Child Health and Human Development.


Assuntos
Infecções por HIV , HIV-1 , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Amplamente Neutralizantes/uso terapêutico , Anticorpos Anti-HIV , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Polissacarídeos/uso terapêutico , Masculino
7.
Viruses ; 15(10)2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37896806

RESUMO

The COVE trial randomized participants to receive two doses of mRNA-1273 vaccine or placebo on Days 1 and 29 (D1, D29). Anti-SARS-CoV-2 Spike IgG binding antibodies (bAbs), anti-receptor binding domain IgG bAbs, 50% inhibitory dilution neutralizing antibody (nAb) titers, and 80% inhibitory dilution nAb titers were measured at D29 and D57. We assessed these markers as correlates of protection (CoPs) against COVID-19 using stochastic interventional vaccine efficacy (SVE) analysis and principal surrogate (PS) analysis, frameworks not used in our previous COVE immune correlates analyses. By SVE analysis, hypothetical shifts of the D57 Spike IgG distribution from a geometric mean concentration (GMC) of 2737 binding antibody units (BAU)/mL (estimated vaccine efficacy (VE): 92.9% (95% CI: 91.7%, 93.9%)) to 274 BAU/mL or to 27,368 BAU/mL resulted in an overall estimated VE of 84.2% (79.0%, 88.1%) and 97.6% (97.4%, 97.7%), respectively. By binary marker PS analysis of Low and High subgroups (cut-point: 2094 BAU/mL), the ignorance interval (IGI) and estimated uncertainty interval (EUI) for VE were [85%, 90%] and (78%, 93%) for Low compared to [95%, 96%] and (92%, 97%) for High. By continuous marker PS analysis, the IGI and 95% EUI for VE at the 2.5th percentile (519.4 BAU/mL) vs. at the 97.5th percentile (9262.9 BAU/mL) of D57 Spike IgG concentration were [92.6%, 93.4%] and (89.2%, 95.7%) vs. [94.3%, 94.6%] and (89.7%, 97.0%). Results were similar for other D29 and D57 markers. Thus, the SVE and PS analyses additionally support all four markers at both time points as CoPs.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , COVID-19 , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Imunoglobulina G , Eficácia de Vacinas
8.
EBioMedicine ; 96: 104799, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37738833

RESUMO

BACKGROUND: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. METHODS: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7-15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. FINDINGS: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05-0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01-0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. INTERPRETATION: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. FUNDING: National Institutes of Health.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias/prevenção & controle , SARS-CoV-2 , Estados Unidos , Vacinação
9.
Sci Transl Med ; 15(692): eade9078, 2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-37075127

RESUMO

The best assay or marker to define mRNA-1273 vaccine-induced antibodies as a correlate of protection (CoP) is unclear. In the COVE trial, participants received two doses of the mRNA-1273 COVID-19 vaccine or placebo. We previously assessed IgG binding antibodies to the spike protein (spike IgG) or receptor binding domain (RBD IgG) and pseudovirus neutralizing antibody 50 or 80% inhibitory dilution titer measured on day 29 or day 57, as correlates of risk (CoRs) and CoPs against symptomatic COVID-19 over 4 months after dose. Here, we assessed a new marker, live virus 50% microneutralization titer (LV-MN50), and compared and combined markers in multivariable analyses. LV-MN50 was an inverse CoR, with a hazard ratio of 0.39 (95% confidence interval, 0.19 to 0.83) at day 29 and 0.51 (95% confidence interval, 0.25 to 1.04) at day 57 per 10-fold increase. In multivariable analyses, pseudovirus neutralization titers and anti-spike binding antibodies performed best as CoRs; combining antibody markers did not improve correlates. Pseudovirus neutralization titer was the strongest independent correlate in a multivariable model. Overall, these results supported pseudovirus neutralizing and binding antibody assays as CoRs and CoPs, with the live virus assay as a weaker correlate in this sample set. Day 29 markers performed as well as day 57 markers as CoPs, which could accelerate immunogenicity and immunobridging studies.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV , COVID-19 , Humanos , Eficácia de Vacinas , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Imunoglobulina G , Anticorpos Antivirais
11.
NPJ Vaccines ; 8(1): 36, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36899062

RESUMO

In the phase 3 trial of the AZD1222 (ChAdOx1 nCoV-19) vaccine conducted in the U.S., Chile, and Peru, anti-spike binding IgG concentration (spike IgG) and pseudovirus 50% neutralizing antibody titer (nAb ID50) measured four weeks after two doses were assessed as correlates of risk and protection against PCR-confirmed symptomatic SARS-CoV-2 infection (COVID-19). These analyses of SARS-CoV-2 negative participants were based on case-cohort sampling of vaccine recipients (33 COVID-19 cases by 4 months post dose two, 463 non-cases). The adjusted hazard ratio of COVID-19 was 0.32 (95% CI: 0.14, 0.76) per 10-fold increase in spike IgG concentration and 0.28 (0.10, 0.77) per 10-fold increase in nAb ID50 titer. At nAb ID50 below the limit of detection (< 2.612 IU50/ml), 10, 100, and 270 IU50/ml, vaccine efficacy was -5.8% (-651%, 75.6%), 64.9% (56.4%, 86.9%), 90.0% (55.8%, 97.6%) and 94.2% (69.4%, 99.1%). These findings provide further evidence towards defining an immune marker correlate of protection to help guide regulatory/approval decisions for COVID-19 vaccines.

12.
Nat Commun ; 14(1): 331, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658109

RESUMO

In the PREVENT-19 phase 3 trial of the NVX-CoV2373 vaccine (NCT04611802), anti-spike binding IgG concentration (spike IgG), anti-RBD binding IgG concentration (RBD IgG), and pseudovirus 50% neutralizing antibody titer (nAb ID50) measured two weeks post-dose two are assessed as correlates of risk and as correlates of protection against COVID-19. Analyses are conducted in the U.S. cohort of baseline SARS-CoV-2 negative per-protocol participants using a case-cohort design that measures the markers from all 12 vaccine recipient breakthrough COVID-19 cases starting 7 days post antibody measurement and from 639 vaccine recipient non-cases. All markers are inversely associated with COVID-19 risk and directly associated with vaccine efficacy. In vaccine recipients with nAb ID50 titers of 50, 100, and 7230 international units (IU50)/ml, vaccine efficacy estimates are 75.7% (49.8%, 93.2%), 81.7% (66.3%, 93.2%), and 96.8% (88.3%, 99.3%). The results support potential cross-vaccine platform applications of these markers for guiding decisions about vaccine approval and use.


Assuntos
COVID-19 , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Imunoglobulina G , SARS-CoV-2 , Eficácia de Vacinas , Ensaios Clínicos Fase III como Assunto
13.
Food Chem ; 405(Pt B): 134947, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36410213

RESUMO

The subunit of tropomyosin (α-TM) from Haliotis discus hannai is an important allergen. The methods to reduce the immunoreactivity of α-TM are worth investigating. Thus, this study confirmed the reacted conditions of α-TM with transglutaminase (TG)-catalyzed cross-linking reaction, TG-catalyzed glycosylation, and glycation. Three processing technologies reduced significantly the contents of α-helix and hydrophobic force of α-TM and increased the surface hydrophobicity. A serological experiment confirmed that the glycated α-TM with xylose showed the lowest IgG/IgE-binding capacity. The inhabitation dot blot displayed that five epitope peptides could bind with the site-specific IgE prepared by the glycated α-TM. Three in nine glycated sites (M68, N202, and N203) were verified to modify-two epitopes (L-HTM-3 and L-HTM-7) of α-TM, which affected the immunoreactivity of α-TM during glycation. These results indicated that glycation would be desired for developing hypo-allergenic abalone products.


Assuntos
Gastrópodes , Tropomiosina , Animais , Tropomiosina/genética , Gastrópodes/genética , Epitopos , Transglutaminases , Glicopirrolato , Imunoglobulina E
14.
Nat Microbiol ; 7(12): 1996-2010, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36357712

RESUMO

Measuring immune correlates of disease acquisition and protection in the context of a clinical trial is a prerequisite for improved vaccine design. We analysed binding and neutralizing antibody measurements 4 weeks post vaccination as correlates of risk of moderate to severe-critical COVID-19 through 83 d post vaccination in the phase 3, double-blind placebo-controlled phase of ENSEMBLE, an international randomized efficacy trial of a single dose of Ad26.COV2.S. We also evaluated correlates of protection in the trial cohort. Of the three antibody immune markers we measured, we found most support for 50% inhibitory dilution (ID50) neutralizing antibody titre as a correlate of risk and of protection. The outcome hazard ratio was 0.49 (95% confidence interval 0.29, 0.81; P = 0.006) per 10-fold increase in ID50; vaccine efficacy was 60% (43%, 72%) at non-quantifiable ID50 (<2.7 IU50 ml-1) and increased to 89% (78%, 96%) at ID50 = 96.3 IU50 ml-1. Comparison of the vaccine efficacy by ID50 titre curves for ENSEMBLE-US, the COVE trial of the mRNA-1273 vaccine and the COV002-UK trial of the AZD1222 vaccine supported the ID50 titre as a correlate of protection across trials and vaccine types.


Assuntos
Ad26COVS1 , COVID-19 , Humanos , COVID-19/prevenção & controle , ChAdOx1 nCoV-19 , Vacina de mRNA-1273 contra 2019-nCoV , Eficácia de Vacinas , Anticorpos Neutralizantes
15.
Food Funct ; 13(17): 9078-9090, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35943407

RESUMO

Tropomyosin (TM) is an important allergen in molluscans. However, there was a lack of information about TM as an allergen in oysters. TM was purified and identified from Alectryonella plicatula (ATM), and its primary sequence was cloned and encoded with 284 amino acids (AAs). Chemical denaturants were used to destroy the structure to confirm that linear epitopes played a major role in the immunoglobulin E-binding capacity of ATM. Subsequently, nine linear epitopes were identified using a serological test. The peptide with AA27-41 was regarded as the key epitope because it could be recognized strongly by most sera of oyster-sensitive individuals in comparison to other epitope peptides. Finally, the epitopes and the primary sequence of TM among shellfish were aligned to find the two conserved epitopes (AA117-132 and AA164-178) in oyster, octopus, abalone, scallop, clam, shrimp, and crab. Overall, these data provide a foundation for the allergenicity and cross-reactivity of TM.


Assuntos
Ostreidae , Tropomiosina , Alérgenos , Sequência de Aminoácidos , Animais , Epitopos/química , Imunoglobulina E , Peptídeos , Tropomiosina/química
16.
J Leukoc Biol ; 112(5): 1167-1181, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35866359

RESUMO

The HIV Vaccine Trials Network (HVTN) conducts clinical trials on 4 continents in pursuit of a safe and effective HIV vaccine. Cellular immune responses to vaccination that define vaccine immunogenicity and/or immune correlates of protection can be measured using multiparameter intracellular cytokine staining (ICS) assays. The HVTN cellular immunology laboratory, located in Seattle, WA, conducts ICS assays for vaccine trials according to Good Clinical Laboratory Practices (GCLP). In 2013, the HVTN established a second GCLP compliant cellular immunology laboratory in Cape Town, South Africa to assess vaccine immunogenicity for HVTN trials conducted on the African continent. To ensure ICS readouts in the 2 laboratories were directly comparable, we conducted concordance testing using PBMC from healthy controls and vaccine trial participants. Despite standardized procedures and instrumentation, shared quality control measures and quality assurance oversight, several factors impacted our ability to obtain close agreement in T-cell responses measured in the 2 laboratories. One of these was the type of fetal bovine serum (FBS) used in the assay, which impacted lymphocyte cell viability and background responses. In addition, the differences in supernatant removal technique also significantly affected our ability to detect positive responses to vaccine antigens. Standardization of these factors allowed us to achieve and maintain ICS assay concordance across the 2 laboratories over multiple years, accelerating our efforts to evaluate HIV vaccines. The insights gained in this process are valuable for assay transfer efforts by groups of investigators that need to directly compare data generated in different laboratories around the globe.


Assuntos
Vacinas contra a AIDS , Infecções por HIV , Humanos , Leucócitos Mononucleares , Soroalbumina Bovina , Linfócitos T , África do Sul , Infecções por HIV/prevenção & controle , Citocinas , Coloração e Rotulagem
17.
medRxiv ; 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35441174

RESUMO

Anti-spike IgG binding antibody, anti-receptor binding domain IgG antibody, and pseudovirus neutralizing antibody measurements four weeks post-vaccination were assessed as correlates of risk of moderate to severe-critical COVID-19 outcomes through 83 days post-vaccination and as correlates of protection following a single dose of Ad26.COV2.S COVID-19 vaccine in the placebo-controlled phase of ENSEMBLE, an international, randomized efficacy trial. Each marker had evidence as a correlate of risk and of protection, with strongest evidence for 50% inhibitory dilution (ID50) neutralizing antibody titer. The outcome hazard ratio was 0.49 (95% confidence interval 0.29, 0.81; p=0.006) per 10-fold increase in ID50; vaccine efficacy was 60% (43, 72%) at nonquantifiable ID50 (< 2.7 IU50/ml) and rose to 89% (78, 96%) at ID50 = 96.3 IU50/ml. Comparison of the vaccine efficacy by ID50 titer curves for ENSEMBLE-US, the COVE trial of the mRNA-1273 vaccine, and the COV002-UK trial of the AZD1222 vaccine supported consistency of the ID50 titer correlate of protection across trials and vaccine types.

18.
Oxid Med Cell Longev ; 2022: 2479956, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35340216

RESUMO

It was the focus of attention that probiotic control drink was packed with prebiotic nutrients and lactic acid bacteria. So, this study is aimed at revealing that the fermented carrot pulp regulation and protection function to the intestinal microecological disorders usually induced by antibiotic treatment. First, we study on lactobacillus fermentation conditions and effects on the secondary metabolism of fermented carrot juice, get its phenolic acids up, and get its flavonoids down. Then, establishment of the dysbacteriosis mouse model was used to validate the fermented carrot pulp prevention and treatment of intestinal microbiota imbalance. After the antibiotic treatment, the mice showed impotence, laziness, slow movement, weight loss, thin feces, dull hair, and anal redness, while the mice in the control group were all normal in terms of the mental state, diet, weight, and bowl movement. Along with the treatment, the abnormal conditions of the mice in the model group and natural recovery group improved in different degrees, indicating that the fermentation treatment is of help to the intestinal microbiota recovery. The fermentation-treated group of mice recovered close to normal that the diarrhea disappeared, and the weight gain, mental state, and the feces became normal. The serum antioxidant (SOD, GSH, and MDA) levels of the mice were checked. The superoxide dismutase (SOD) levels and glutathione (GSH) levels in the ordinary fermentation-treated group and probiotic fermentation-treated group were significantly increased compare to the natural recovery group. The malondialdehyde (MDA) levels showed great differences between the fermentation-treated groups and the blank group. At last, the 16sRNA analysis revealed that the microbiota richness and diversity in probiotic fermentation (J) are much higher than those in the model group (H), ordinary fermentation group (I), and blank group (G). Groups J and I are of significantly higher antioxidant level than group H; however, only the glutathione (GSH) level in group J increased dramatically but not those in the other three groups. Antibiotic treatment-induced mouse intestinal microecological disorder reduce the microbiota richness and diversity. Prebiotics fermented carrot pulp treatment can help in the recovery from the microbiota richness and diversity level prior to the antibiotic treatment, which suggests it can regulate and protect the murine intestinal microbiome.


Assuntos
Daucus carota , Microbioma Gastrointestinal , Probióticos , Animais , Daucus carota/metabolismo , Daucus carota/microbiologia , Disbiose , Fermentação , Masculino , Camundongos
19.
Science ; 375(6576): 43-50, 2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34812653

RESUMO

In the coronavirus efficacy (COVE) phase 3 clinical trial, vaccine recipients were assessed for neutralizing and binding antibodies as correlates of risk for COVID-19 disease and as correlates of protection. These immune markers were measured at the time of second vaccination and 4 weeks later, with values reported in standardized World Health Organization international units. All markers were inversely associated with COVID-19 risk and directly associated with vaccine efficacy. Vaccine recipients with postvaccination 50% neutralization titers 10, 100, and 1000 had estimated vaccine efficacies of 78% (95% confidence interval, 54 to 89%), 91% (87 to 94%), and 96% (94 to 98%), respectively. These results help define immune marker correlates of protection and may guide approval decisions for messenger RNA (mRNA) COVID-19 vaccines and other COVID-19 vaccines.


Assuntos
Vacina de mRNA-1273 contra 2019-nCoV/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Eficácia de Vacinas , Adolescente , Adulto , Idoso , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Ensaios Clínicos Fase III como Assunto , Feminino , Humanos , Imunogenicidade da Vacina , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto Jovem
20.
J Agric Food Chem ; 69(50): 15403-15413, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34881872

RESUMO

Tropomyosin (TM) was reported to be a supercoil allergen of shellfish. However, little information is available about its link between structure and allergenicity. In this study, the subunit of TM (α-TM) and supercoil of TM (α2-TM) were identified from Haliotis discus hannai. α2-TM showed higher immunoreactivity than α-TM. Meanwhile, seven linear epitopes in α-TM and α2-TM were verified, and two conformational epitopes in α2-TM were predicted. The physicochemical properties and chemical bond assays confirmed the existence of the disulfide bond in α2-TM. According to spectroscopy and hydrophobicity analysis, α-TM showed higher α-helix features and blueshift of the fluorescence intensity peak compared with those of α2-TM. The structure analysis revealed the possibility of conformational epitopes in α2-TM, which could explain the immunoreactivity differences between α-TM and α2-TM further. These results improved the understanding of Haliotis discus hannai TM, which lay the foundation for the food processing of abalone.


Assuntos
Gastrópodes , Tropomiosina , Animais , Epitopos , Imunoglobulina E , Frutos do Mar
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