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Biology subjects

Lopez-Granados, E.

Publications and source records attributed to Lopez-Granados, E..

3 recordsLinked to original sources

A high-resolution, unbiased analysis of the cellular immune response to Epstein-Barr virus

More than 95% of humans are infected with Epstein-Barr virus (EBV), yet although EBV infection has been associated with inflammatory and autoimmune diseases, lymphoproliferative disorders, and several types of cancer, for the vast majority of infected people the infection is asymptomatic as EBV replication is controlled by the immune system. Immunity against this virus has been studied since the discovery of EBV in the 1960s, and although important insights have been made, no unbiased, global studies of immune responses to EBV in healthy seropositive subjects have been reported. Here we describe a novel protocol to study the cellular immune response to EBV, detecting lymphocytes that respond to EBV via analyses of proliferation or induced expression of activation markers and cytokines. Using this system we sequenced, for the first time at a single-cell level, the transcriptome of all cells capable of responding to EBV in healthy individuals and in patients with inborn errors of immunity (IEI) associated with susceptibility to EBV infection. Lymphocyte cytotoxicity appears to be crucial for the proper control of EBV-infection, while a proportionate T-regulatory cell response likely helps to avoid excessive immunity and immune pathology. We also show that {gamma}{delta} T cells expressing the TCR V{delta}1 chain use various activating natural killer (NK) cell receptors to recognise and kill EBV-infected lymphoblastoid cell lines (LCLs) and thus could be a promising candidate for allogeneic cell therapy for EBV-associated lymphoproliferative disorders in patients with either primary or secondary immunodeficiencies. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=186 HEIGHT=200 SRC="FIGDIR/small/681317v1_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@116ad85org.highwire.dtl.DTLVardef@1da33d7org.highwire.dtl.DTLVardef@81a2a6org.highwire.dtl.DTLVardef@dd571d_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Single-Cell Atlas of Common Variable Immunodeficiency reveals germinal center-associated epigenetic dysregulation in B cell responses

Common variable immunodeficiency (CVID), the most prevalent symptomatic primary immunodeficiency, is characterized by impaired terminal B-cell differentiation and defective antibody responses. Incomplete genetic penetrance and a wide range of phenotypic expressivity in CVID suggest the participation of additional pathogenic mechanisms. Monozygotic (MZ) twins discordant for CVID are uniquely valuable for studying the contribution of epigenetics to the disease. We used single-cell epigenomics and transcriptomics to create a cell census of naive-to-memory B cell differentiation in a pair of CVID-discordant MZ twins. Our analysis identifies DNA methylation, chromatin accessibility and transcriptional defects in memory B cells that mirror defective cell-cell communication defects following activation. These findings were validated in a cohort of CVID patients and healthy donors. Our findings provide a comprehensive multi-omics map of alterations in naive-to-memory B-cell transition in CVID and reveal links between the epigenome and immune cell cross-talk. Our resource, publicly available at the Human Cell Atlas, paves the way for future diagnosis and treatments of CVID patients.

immunology↗

Differential effects of the second SARS-CoV-2 mRNA vaccine dose on T cell immunity in naive and COVID-19 recovered individuals

The rapid development and deployment of mRNA-based vaccines against the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) led to the design of accelerated vaccination schedules that have been extremely effective in naive individuals. While a two-dose immunization regimen with the BNT162b2 vaccine has been demonstrated to provide a 95% efficacy in naive individuals, the effects of the second vaccine dose in individuals who have previously recovered from natural SARS-CoV-2 infection has been questioned. Here we characterized SARS-CoV-2 spike-specific humoral and cellular immunity in naive and previously infected individuals during full BNT162b2 vaccination. Our results demonstrate that the second dose increases both the humoral and cellular immunity in naive individuals. On the contrary, the second BNT162b2 vaccine dose results in a reduction of cellular immunity in COVID-19 recovered individuals, which suggests that a second dose, according to the current standard regimen of vaccination, may be not necessary in individuals previously infected with SARS-CoV-2.

immunology↗