Assessment of immune correlates of severe COVID-19 has been hampered by the low numbers of severe cases in COVID-19 vaccine efficacy (VE) trials. We assess neutralizing and binding antibody levels at 4 weeks post-Ad26.COV2.
View Article and Find Full Text PDFCOVID-19 vaccine boosters may optimize durability of protection against variants of concern (VOCs). In this randomized, double-blind, phase 2 trial, participants received 3 different dose levels of an Ad26.COV2.
View Article and Find Full Text PDFWithout clinical efficacy data, vaccine protective effect may be extrapolated from animals to humans using an immunologic marker that correlates with protection in animals. This immunobridging approach was used for the two-dose Ebola vaccine regimen Ad26.ZEBOV, MVA-BN-Filo.
View Article and Find Full Text PDFMeasuring 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.
View Article and Find Full Text PDFAnti-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.
View Article and Find Full Text PDFBackground: IgD is an enigmatic antibody isotype best known when coexpressed with IgM on naive B cells. However, increased soluble IgD (sIgD) levels and increased IgDIgM B-cell populations have been described in the human upper respiratory mucosa.
Objective: We assessed whether levels of sIgD and IgD B cell counts are altered in nasal tissue from patients with chronic rhinosinusitis (CRS).
Background: Complement plays a major role in inflammatory diseases, but its involvement and mechanisms of activation in patients with chronic rhinosinusitis (CRS) are not known.
Objectives: After earlier studies discovering autoantibodies in patients with CRS, we sought to investigate the nature, extent, and location of complement activation in nasal tissue of patients with CRS. Specifically, we were interested in whether antibody-mediated activation through the classical pathway was a major mechanism for complement activation in patients with CRS.
Successful vaccine development against HIV will likely require the induction of strong, long-lasting humoral and cellular immune responses in both the systemic and mucosal compartments. Based on the known immunological linkage between the upper-respiratory and urogenital tracts, we explored the potential of nasal adjuvants to boost immunization for the induction of vaginal and systemic immune responses to gp140. Mice were immunized intranasally with HIV gp140 together with micellar and emulsion formulations of a synthetic TLR4 agonist, Glucopyranosyl Lipid Adjuvant (GLA) and responses were compared to R848, a TLR7/8 agonist, or chitosan, a non TLR adjuvant.
View Article and Find Full Text PDFThe development of a successful vaccine against HIV is likely to require the induction of strong and long-lasting humoral immune responses at the mucosal portal of virus entry. Hence, the design of a vaccine strategy able to induce mucosal antibodies and in particular specific IgA, may be crucial to providing immune protection. Nasal immunisation is known to induce specific IgG and IgA responses in the cervicovaginal mucosa; however, there is an urgent need for the development of safe, effective and accessible mucosal adjuvants for nasal application in humans.
View Article and Find Full Text PDFInduction of humoral responses to HIV at mucosal compartments without inflammation is important for vaccine design. We developed charged wax nanoparticles that efficiently adsorb protein antigens and are internalized by DC in the absence of inflammation. HIV-gp140-adsorbed nanoparticles induced stronger in vitro T-cell proliferation responses than antigen alone.
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