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1.
researchsquare; 2022.
Preprint in English | PREPRINT-RESEARCHSQUARE | ID: ppzbmed-10.21203.rs.3.rs-1229520.v1

ABSTRACT

Background: SARS-CoV-2-specific immune response features in people with HIV infection (PWH) remain to be fully elucidated. We aimed to evaluate the impact of HIV over humoral and cellular responses in COVID-19 convalescent PWH. Methods Blood samples from 29 PWH with preserved CD4+T-cell counts on ART and 29 HIV-negative (HIVneg) donors were included. SARS-CoV-2-specific IgG levels and IgG titers were determined by ELISA. Antibody neutralization capacity was evaluated against the reference B1 strain SARS-CoV-2. IFN-γ-secreting cells were detected by ELISpot using SARS-CoV-2 Spike, RBD, or Nucleocapsid protein or overlapping peptide pools. Frequency and phenotype of T, B and NK cells and levels of soluble cytokines and chemokines were assessed by flow cytometry. Results SARS-CoV-2-specific antibodies were detected on 65.5% of PWH and 79.3% of HIVneg individuals, with no differences in serum IgG levels and anti-SARS-CoV-2 neutralizing antibodies. All donors exhibited SARS-CoV-2-specific cellular immunity, including those with undetectable antibody responses. PWH showed diminished percentages of antibody-secreting cells compared to HIVneg cohort, with similar B cell proportions between groups. PWH presented an increment in T follicular helper (Tfh, CD4+CXCR5+) percentage, which negatively correlated with IgG titers. Additionally, CD4+PD1+ and CD8+HLA-DR+ cell frequencies were augmented in PWH. Moreover, PWH presented a high proportion of CD95+, CD25+, NKp46+, HLA-DR+, and CD38+/HLA-DR+ NK cells. Both groups displayed similar Tregs frequency, effector/memory, and T-helper profile for CD4TL, exhaustion and memory phenotypes for CD8TL and subtle differences in classical monocytes. Profile of circulating cytokines and chemokines was significantly different between both groups. Magnitude of IFN-γ responses to S or N proteins, and RBD was lower in PWH compared to HIVneg donors. Correlation analysis of immune and clinical parameters showed a distinct immune landscape in the PWH group. Conclusions PWH showed a distinctive immune profile although severity of COVID-19 was not exacerbated. PWH with conserved CD4+T-cell counts exerted both humoral and cellular responses against SARS-CoV-2. Even though cellular response was lower compared to HIVneg individuals, PWH achieved similar antibody responses with a high neutralization capacity. These data reinforce the impact of ART, not only in controlling HIV but also other infections.


Subject(s)
HIV Infections , COVID-19
2.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.08.22.21262186

ABSTRACT

Recent studies have shown a temporal increase in the neutralizing antibody potency and breadth to SARS-CoV-2 variants in coronavirus disease 2019 (COVID-19) convalescent individuals. Here, we observed a similar process after Sputnik V vaccination. We examined the longitudinal antibody responses and viral neutralizing capacity to variants of concern (VOCs: Alpha, Beta, Gamma, and Delta) and a broadly spread variant of interest (VOI: Lambda) in volunteers up to 6 months after receiving the Sputnik V vaccine in Argentina. A collection of 1,800 serum samples obtained between January and August 2021 was used. The analysis indicates that while anti-spike IgG levels significantly wane over time, the neutralizing potency to the first-wave linages of SARS-CoV-2 and VOC increases within four months of vaccination, suggesting that antibody maturation occurs. This increase was more evident for the Beta and Gamma variants, which showed the highest propensity for neutralization escape. Our observations suggest that protection increases over the six months following vaccination as a consequence of antibody maturation, resulting in improved potency of antibodies to viral escape mutations.


Subject(s)
COVID-19 , Severe Acute Respiratory Syndrome
3.
medrxiv; 2021.
Preprint in English | medRxiv | ID: ppzbmed-10.1101.2021.01.31.21250167

ABSTRACT

Background: Biobanks are instrumental for accelerating research. Early in SARS-CoV-2 pandemic, the Argentinean Biobank of Infectious Diseases (BBEI) initiated the COVID19 collection and started its characterization. Methods: Blood samples from subjects with confirmed SARS-CoV-2 infection either admitted to health institutions or outpatients, were enrolled. Highly exposed seronegative individuals, were also enrolled. Longitudinal samples were obtained in a subset of donors, including persons who donated plasma for therapeutic purposes (plasma donors). SARS-CoV-2-specific IgM and IgG levels, IgG titers and IgG viral neutralization capacity were determined. Findings: Out of 825 donors, 57.1% were females and median age was 41 years (IQR 32-53 years). Donors were segregated as acute or convalescent donors, and mild versus moderate/severe disease donors. Seventy-eight percent showed seroconversion to SARS-CoV-2 specific antibodies. Specific IgM and IgG showed comparable positivity rates in acute donors. IgM detectability rate declined in convalescent donors while IgG detectability remained elevated in early (74,8%) and late (83%) convalescent donors. Among donors with follow-up samples, IgG levels seemed to decline more rapidly in plasma donors. IgG levels were higher with age, disease severity, number of symptoms, and was more durable in moderate/severe disease donors. Levels and titers of anti-spike/RBD IgG strongly correlated with neutralization activity against WT virus. Interpretation: The BBEI-COVID19 collection served a dual role in this SARS-CoV-2 global crisis. First, it feed researchers and developers transferring samples and data to fuel research projects. Second, it generated highly needed local data to understand and frame the regional dynamics of the infection.


Subject(s)
COVID-19 , Communicable Diseases
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