Publications by authors named "Dimeglio C"
Article Synopsis
- The study aimed to compare the antibody response to SARS-CoV-2 in patients with inflammatory rheumatic diseases and healthy individuals.
- Researchers screened unvaccinated patients with conditions like rheumatoid arthritis, spondyloarthritis, and psoriatic arthritis in France, and matched them with seropositive healthcare workers as controls.
- Results showed no significant difference in antibody levels between both groups, with a trend indicating that patients with severe COVID-19 symptoms had higher antibody titres; treatments like glucocorticoids seemed linked to lower antibody responses.
Unlabelled: Hepatitis E virus is a single-strand, positive-sense RNA virus that can lead to chronic infection in immunocompromised patients. Virus-host recombinant variants (VHRVs) have been described in such patients. These variants integrate part of human genes into the polyproline-rich region that could introduce new post-translational modifications (PTMs), such as ubiquitination.
View Article and Find Full Text PDFOur understanding of cellular immunity in response to COVID-19 infection or vaccination is limited because of less commonly used techniques. We investigated both the cellular and humoral immune responses before and after the administration of a third dose of the SARS-CoV-2 vaccine among a group of healthcare workers. Cellular immunity was evaluated using the VIDAS interferon-gamma (IFNγ) RUO test, which enables automated measurement of IFNγ levels after stimulating peripheral blood lymphocytes.
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- This study investigates the role of the gut as a reservoir for intact HIV-1 proviruses, which contribute to viral rebound in patients on antiretroviral therapy.
- Blood samples and intestinal biopsies from 42 HIV-1 positive individuals revealed that intact proviruses are notably concentrated in the colon, and their presence is linked to ongoing immune activation.
- The research suggests that the gut's HIV-1 reservoir is influenced by the proliferation of specific T cells, highlighting the gut's significance in maintaining viral persistence despite treatment.
Evaluation of two anti-SARS-CoV-2 antibody immunoassays for monitoring patients on pre-exposure prophylaxis.
Diagn Microbiol Infect Dis
December 2023
Pre-exposure prophylaxis (PrEP) is crucial to prevent severe COVID-19 in immunocompromised patients. A reliable method is needed to quantify anti-SARS-CoV-2 antibody levels for personalized monitoring during PrEP. We measured the binding antibody concentrations of 63 immunocompromised patients receiving 300mg or 600mg tixagevimab/cilgavimab on PrEP day and twice during the following 3 months.
View Article and Find Full Text PDFThe vaccines presently available are less effective in older people due to senescence of their immune systems. We measured the antibody responses of 42 adults living in nursing homes after the third and the fourth doses of an mRNA vaccine and found that the strain (BA.2 and BA.
View Article and Find Full Text PDFNew variants and genetic mutations of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome can only be identified using accurate sequencing methods. Single molecule real-time (SMRT) sequencing has been used to characterize Alpha and Delta variants, but not Omicron variants harboring numerous mutations in the SARS-CoV-2 genome. This study assesses the performance of a target capture SMRT sequencing protocol for whole genome sequencing (WGS) of SARS-CoV-2 Omicron variants and compared it to that of an amplicon SMRT sequencing protocol optimized for Omicron variants.
View Article and Find Full Text PDFObjectives: To evaluate the routine use of the Sentosa ultra-deep sequencing (UDS) system for HIV-1 polymerase resistance genotyping in treatment-naïve individuals and to analyse the virological response (VR) to first-line antiretroviral treatment.
Methods: HIV drug resistance was determined on 237 consecutive samples from treatment-naïve individuals using the Sentosa UDS platform with two mutation detection thresholds (3% and 20%). VR was defined as a plasma HIV-1 virus load <50 copies/mL after 6 months of treatment.
The present study aimed to determine whether current commercial immunoassays are adequate for detecting anti-Omicron antibodies. We analyzed the anti-SARS-CoV-2 antibody response of 23 unvaccinated individuals 1-2 months after an Omicron infection. All blood samples were tested with a live virus neutralization assay using a clinical Omicron BA.
View Article and Find Full Text PDFThe emergence of the SARS-CoV-2 variants of concern has greatly influenced the immune correlates of protection, and there are little data about the antibody threshold concentrations to protect against infection with SARS-CoV-2 Omicron BA.1 or BA.2.
View Article and Find Full Text PDFFast, accurate sequencing methods are needed to identify new variants and genetic mutations of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome. Single-molecule real-time (SMRT) Pacific Biosciences (PacBio) provides long, highly accurate sequences by circular consensus reads. This study compares the performance of a target capture SMRT PacBio protocol for whole-genome sequencing (WGS) of SARS-CoV-2 to that of an amplicon PacBio SMRT sequencing protocol.
View Article and Find Full Text PDFThe neutralizing antibody response is a key component of adaptive immunity and a primary protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The increased transmissibility of the SARS-CoV-2 Delta variant and its capacity to cause more severe disease could be linked to a significant reduction in neutralizing antibodies generated during a previous infection or vaccination. We analyzed blood samples from 162 unvaccinated health care workers (HCWs) collected 1 to 3 months postinfection and from 263 vaccinated health care workers 1 month after the last injection.
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- - We studied the evolution of Omicron sublineages of the SARS-CoV-2 virus from December 2021 to mid-March 2022 using a specific type of PCR method.
- - The research focused on comparing the BA.2 variant to the BA.1 variant to understand their dynamics during this period.
- - Findings indicate that BA.2’s advantage over BA.1 isn't linked to higher amounts of the virus found in the nasopharynx.
Article Synopsis
- A study conducted at Toulouse University Hospital analyzed the nasopharyngeal viral load (VL) of SARS-CoV-2 in 3775 patients infected with Delta and Alpha variants, focusing on how vaccination status impacted these levels.
- The findings revealed that Delta variant infections had significantly higher VL compared to Alpha infections, particularly in patients diagnosed later after symptom onset.
- Vaccinated individuals showed lower VL regardless of the variant, indicating that vaccination could help reduce viral spread, especially with the more contagious Delta variant.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in December 2019 and caused a dramatic pandemic. Serological assays are used to check for immunization and assess herd immunity. We evaluated commercially available assays designed to quantify antibodies directed to the SARS-CoV-2 Spike (S) antigen, either total (Wantaï SARS-CoV-2 Ab ELISA) or IgG (SARS-CoV-2 IgG II Quant on Alinity, Abbott, and Liaison SARS-CoV-2 TrimericS IgG, Diasorin).
View Article and Find Full Text PDFBackground: The recent emergence of new SARS CoV-2 variants (variants of concern, VOC) that spread rapidly and may lead to immune escape has emphasized the urgent need to monitor and control their spread.
Methods: We analyzed 2018 SARS-CoV-2 positive specimens collected between February 9 and March 22, 2021 using the Thermofisher® TaqPath™ COVID-19 CE-IVD RT-PCR kit (TaqPath) and the ID solutions® ID™ SARS-CoV-2/UK/SA Variant Triplex RT-PCR (ID triplex) assay to screen for VOCs.
Results: The ID triplex assay identified 62.