Murine B cell response to immunization with SARS-CoV-2
Ontology highlight
ABSTRACT: We performed single-cell gene expression and V(D)J profiling to interrogate the blood plasmablast response in mice immunized with the receptor binding domain of the SARS-CoV-2 spike protein.
Project description:We studied the impact of a vaccine prime dose on CD8 T cell gene expression We first immunized mice with an Ad5-SARS CoV-2 spike vaccine and then evaluated gene expression on SARS CoV-2 specific CD8 T cells at week 4.
Project description:This experiment aims to profile polyclonal antibody binding profiles in serum from vaccinated animals relative to antibody function in a virus neutralization assay. Rabbits received three vaccinations with a DNA vaccine encoding the spike protein of the SARS-CoV-2 index strain. Serum samples were selected based on a three-tier (low, intermediate, and high) capacity to cross-neutralize SARS-CoV-2 strains with known neutralization resistance. Following normalization of total anti-spike IgG levels, serum of each animal (n=3) were evaluated for antibody binding to 10mer cyclic constrained peptides spanning the entire spike protein and regions with known SARS-CoV-2 variant of concern spike mutations.
Project description:To better understand the biological pathways by which UV inactivated SARS-CoV-induced pulmonary eosinophilia occurs, we examined global transcriptional changes in macrophages from the lungs of mouse. Female BALB/c mice were used at 21 weeks of age. Mice were subcutaneously immunized with UV inactivated SARS-CoV (UV-V) or UV-V and Toll like receptor (TLR) ligands at 6 and 1 weeks prior to mouse-adapted SARS-CoV (n=6 per group). Mice were intranasally challenged with 1E+6 TCID50 in 30M-NM-<L. MEM was challenged in six mice as control infection. Mice were sacrificed and collected lungs at 1 days after challenge, then CD11b positive cells were isolated from the lungs of these mice. These cells were used for the analysis of microarray.
Project description:The infrequently altered SARS-CoV-2 protein RNA dependent RNA polymerase (RdRp) is a promising target for T cell-targeting mRNA vaccines. We used single cell RNA sequencing (scRNA-seq) to define the transcriptional profile and TCR repertoire of CD8+ cells in mice immunized with a mRNA vaccine encoding SARS-CoV-2.
Project description:The experiment aims at characterizing the immune responses elicited by the BNT162b2 vaccine against SARS-CoV-2, initially administered in a two dose regimen (second dose after three weeks followinf the first dose) In particular the transcriptional landscape of circulating T and B lymphocytes has been profiled longitudinnaly by scRNA-seq coupleD with CITE-seq of 19 cell surface markers to better classify T cells subpopulations, LIBRA-seq to assess the Spike-specificity of BCRs and and V(D)J seq to also track T and B cell clones dynamics. Eeach sample was profiled before vaccination (T0), 21 days after the first dose (T1), 2 months after the first dose (1 month after the second dose) (T2). The immune responses were characterized using PBMC from 3 SARS-CoV-2 experienced donors (experiencing SARS-Cov-2 at least 4 months before the first vaccinatin) and 2 SARS-CoV-2 unexperienced donors.
Project description:We generated LNP-mRNA encoding B.1.1.529 SARS-CoV-2 spike, and intramuscularly administered it in a human IgG and IgK knock-in mouse. Single cell VDJ-seq unveiled the sequences of human monoclonal antibodies targeting the B.1.1.529 SARS-CoV-2 spike protein.
Project description:To explore the relationship between SARS-CoV-2 infection in different time before operation and postoperative main complications (mortality, main pulmonary and cardiovascular complications) 30 days after operation; To determine the best timing of surgery after SARS-CoV-2 infection.
Project description:HAE cultures were infected with SARS-CoV, SARS-dORF6 or SARS-BatSRBD and were directly compared to A/CA/04/2009 H1N1 influenza-infected cultures. Cell samples were collected at various hours post-infection for analysis. Time Points = 0, 12, 24, 36, 48, 60, 72, 84 and 96 hrs post-infection for SARS-CoV, SARS-dORF6 and SARS-BatSRBD. Time Points = 0, 6, 12, 18, 24, 36 and 48 hrs post-infection for H1N1. Done in triplicate for RNA Triplicates are defined as 3 different wells, plated at the same time and using the same cell stock for all replicates. Time matched mocks done in triplicate from same cell stock as rest of samples. Culture medium (the same as what the virus stock is in) will be used for the mock infections. Infection was done at an MOI of 2 for SARS viruses and an MOI of 1 for H1N1.
Project description:We here identified that the trimeric spike protein of SARS-CoV-2 could bind to TLR4 directly and robustly activate downstream signaling in monocytes and neutrophils. Moreover, specific TLR4 or NFKB inhibitor, or knockout of MyD88 could significantly block IL-1B induction by spike protein. We thus reveal that spike protein of SARS-CoV-2 functions as a potent stimulus causing TLR4 activation and sepsis related abnormal responses.
Project description:The COVID-19 pandemic prompted an unprecedented effort to develop effective countermeasures against SARS-CoV-2. While efficacious vaccines and certain therapeutic monoclonal antibodies are available, here, we report the development, cryo-EM structures and functional analyses of distinct potent monoclonal antibodies (mAbs) that neutralize SARS-CoV-2 and its variant B.1.351. We established a platform for rapid identification of highly potent and specific SARS-CoV-2-neutralizing antibodies by high-throughput B cell receptor single cell sequencing of spike receptor binding domain immunized animals. We identified two highly potent and specific SARS-CoV-2 neutralizing mAb clones that have single-digit nanomolar affinity and low-picomolar avidity. We also generated a bispecific antibody of these two lead clones. The lead monospecific and bispecific antibodies showed strong neutralization ability against prototypical SARS-CoV-2 and the highly contagious South African variant B.1.351 that post a further risk of reducing the efficacy of currently available therapeutic antibodies and vaccines. The lead mAbs showed potent in vivo efficacy against authentic SARS-CoV-2 in both prophylactic and therapeutic settings. We solved five cryo-EM structures at ~3 resolution of these neutralizing antibodies in complex with the ectodomain of the prefusion spike trimer, and revealed the molecular epitopes, binding patterns and conformations between the antibodies and spike RBD, which are distinct from existing antibodies. Our recently developed antibodies expand the repertoire of the toolbox of COVID-19 countermeasures against the SARS-CoV-2 pathogen and its emerging variants.