Background: The robustness and persistence of vaccine antigen-induced antibodies are often used as proxy indicators of vaccine efficacy, but immune responses to vaccine vectors are typically less well-defined. Our study considered the kinetics of immunoglobulin (IgG) responses against the vector (vesicular stomatitis Indiana virus [VSIV]) nucleoprotein (N) and the inserted antigen (Ebola virus [EBOV]) glycoprotein (GP1,2) components of the rVSVΔG-ZEBOV-GP (rVSV-ZEBOV) vaccine and evaluated their use as biomarkers to confirm self-reported vaccination status.
Methods: From the Partnership for Research on Ebola Virus in Liberia (PREVAIL) I clinical trial (NCT02344407), we randomly selected 212 participants who received rVSV-ZEBOV (n=107) or placebo (n=105).
rVSVΔG-ZEBOV-GP and Ad26.ZEBOV, MVA-BN-Filo are WHO-prequalified vaccination regimens against Ebola virus disease (EVD). Challenges associated with measuring long-term clinical protection warrant the evaluation of immune response kinetics after vaccination.
View Article and Find Full Text PDFLancet Microbe
November 2024
A subset of antiretroviral therapy-treated persons with human immunodeficiency virus (HIV), referred to as immunological nonresponders (INRs), fails to normalize CD4+ T-cell numbers. In a case-control study involving 26 INRs (CD4 < 250 cells/µL) and 25 immunological responders (IRs; CD4 ≥ 250 cells/µL), we evaluated the potential contribution of transcriptionally competent defective HIV-1 proviruses to poor CD4+ T-cell recovery. Compared to the responders, the INRs had higher levels of cell-associated HIV RNA (P = .
View Article and Find Full Text PDFObjectives: People with HIV-1 (PWH) on effective antiretroviral therapy (ART) continue to exhibit chronic systemic inflammation, immune activation, and persistent elevations in markers of HIV-1 infection [including HIV-DNA, cell-associated HIV-RNA (CA HIV-RNA), and antibodies to HIV-1 proteins] despite prolonged suppression of plasma HIV-RNA levels less than 50 copies/ml. Here, we investigated the hypothesis that nonreplicating but transcriptionally and translationally competent 'defective' HIV-1 proviruses may be one of drivers of these phenomena.
Design: A combined cohort of 23 viremic and virologically suppressed individuals on ART were studied.
J Glob Health
July 2023
Background: Minimal data exist on pregnancy following recovery from Ebola in people of child-bearing potential (females aged roughly 18-45 years). The aim of this study was to assess viral persistence or reactivation in pregnancy, the frequency of placental transfer of anti-Ebola IgG antibodies, and pregnancy outcomes in this population.
Methods: In this observational cohort study, we studied self-reported pregnancies in two groups: seropositive people who had recovered from Ebola virus disease (seropositive group) and seronegative people who had close contact with people with Ebola (seronegative group).
Lancet Respir Med
September 2023
Background: There is a clinical need for therapeutics for COVID-19 patients with acute hypoxemic respiratory failure whose 60-day mortality remains at 30-50%. Aviptadil, a lung-protective neuropeptide, and remdesivir, a nucleotide prodrug of an adenosine analog, were compared with placebo among patients with COVID-19 acute hypoxaemic respiratory failure.
Methods: TESICO was a randomised trial of aviptadil and remdesivir versus placebo at 28 sites in the USA.
Background: Discrimination of bacterial and viral etiologies of childhood community-acquired pneumonia (CAP) is often challenging. Unnecessary antibiotic administration exposes patients to undue risks and may engender antimicrobial resistance. This study aimed to develop a prediction model using epidemiological, clinical and laboratory data to differentiate between bacterial and viral CAP.
View Article and Find Full Text PDFBackground: For people with HIV and CD4 counts >500 cells/mm, early initiation of antiretroviral therapy (ART) reduces serious AIDS and serious non-AIDS (SNA) risk compared with deferral of treatment until CD4 counts are <350 cells/mm. Whether excess risk of AIDS and SNA persists once ART is initiated for those who defer treatment is uncertain.
Methods: The Strategic Timing of AntiRetroviral Treatment (START) trial, as previously reported, randomly assigned 4684 ART-naive HIV-positive adults with CD4 counts .
The levels of immune response to SARS-CoV-2 infection or vaccination are poorly understood in African populations and is complicated by cross-reactivity to endemic pathogens as well as differences in host responsiveness. To begin to determine the best approach to minimize false positive antibody levels to SARS-CoV-2 in an African population, we evaluated three commercial assays, namely Bio-Rad Platelia SARS-CoV-2 Total Antibody (Platelia), Quanterix Simoa Semi-Quantitative SARS-CoV-2 IgG Antibody Test (anti-Spike), and the GenScript cPass™ SARS-CoV-2 Neutralization Antibody Detection Kit (cPass) using samples collected in Mali in West Africa prior to the emergence of SARS-CoV-2. A total of one hundred samples were assayed.
View Article and Find Full Text PDFIntroduction: There remains a need to better identify patients at highest risk for developing severe Coronavirus Disease 2019 (COVID-19) as additional waves of the pandemic continue to impact hospital systems. We sought to characterize the association of receptor for advanced glycation end products (RAGE), SARS-CoV-2 nucleocapsid viral antigen, and a panel of thromboinflammatory biomarkers with development of severe disease in patients presenting to the emergency department with symptomatic COVID-19.
Methods: Blood samples were collected on arrival from 77 patients with symptomatic COVID-19, and plasma levels of thromboinflammatory biomarkers were measured.
Background: There is an incompletely understood increased risk for cardiovascular disease (CVD) among people with HIV (PWH). We investigated if a collection of biomarkers were associated with CVD among PWH. Mendelian randomization (MR) was used to identify potentially causal associations.
View Article and Find Full Text PDFBackground: Questions remain concerning the rapidity of immune responses and the durability and safety of vaccines used to prevent Zaire Ebola virus disease.
Methods: We conducted two randomized, placebo-controlled trials - one involving adults and one involving children - to evaluate the safety and immune responses of three vaccine regimens against Zaire Ebola virus disease: Ad26.ZEBOV followed by MVA-BN-Filo 56 days later (the Ad26-MVA group), rVSVΔG-ZEBOV-GP followed by placebo 56 days later (the rVSV group), and rVSVΔG-ZEBOV-GP followed by rVSVΔG-ZEBOV-GP 56 days later (the rVSV-booster group).
Background: The emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants may have contributed to prolonging the pandemic, and increasing morbidity and mortality related to coronavirus disease 2019 (COVID-19). This article describes the dynamics of circulating SARS-CoV-2 variants identified during the different COVID-19 waves in Mali between April and October 2021.
Methods: The respiratory SARS-CoV-2 complete spike (S) gene from positive samples was sequenced.
Background: Studies quantifying SARS-CoV-2 have focused on upper respiratory tract or plasma viral RNA with inconsistent association with clinical outcomes. The association between plasma viral antigen levels and clinical outcomes has not been previously studied. Our aim was to investigate the relationship between plasma SARS-CoV-2 nucleocapsid antigen (N-antigen) concentration and both markers of host response and clinical outcomes.
View Article and Find Full Text PDFBackground: Levels of plasma SARS-CoV-2 nucleocapsid (N) antigen may be an important biomarker in patients with COVID-19 and enhance our understanding of the pathogenesis of COVID-19.
Objective: To evaluate whether levels of plasma antigen can predict short-term clinical outcomes and identify clinical and viral factors associated with plasma antigen levels in hospitalized patients with SARS-CoV-2.
Design: Cross-sectional study of baseline plasma antigen level from 2540 participants enrolled in the TICO (Therapeutics for Inpatients With COVID-19) platform trial from August 2020 to November 2021, with additional data on day 5 outcome and time to discharge.
Eur J Nucl Med Mol Imaging
December 2022
Purpose: Previous SPECT and PET semi-quantitative in vivo imaging studies in monkeys have demonstrated specific uptake of radiolabeled rhesus recombinant anti-CD4 monoclonal antibody fragment CD4R1-F(ab΄) in the spleen and clusters of lymph nodes (LNs) but yielded conflicting results of imaging the gut CD4 + T-cell pool. Here, using PET dynamic imaging with kinetic analysis, we performed a fully quantitative CD4 imaging in rhesus macaques.
Methods: The biodistributions of [Zr]Zr-CD4R1-F(ab΄) and/or of [Zr]Zr-ibalizumab were performed with static PET scans up to 144 h (6 days) post-injection in 18 rhesus macaques with peripheral blood CD4 + T cells/μl ranging from ~ 20 to 2400.