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Hadrup, S. R.

Publications and source records attributed to Hadrup, S. R..

27 records · Page 2Linked to original sources

mRNA-delivered consensus allergens induce a neutralizing IgG response against food and pollen allergens

Pollen-food allergy syndrome (PFAS) affects a significant proportion of the global population with a major health and socioeconomic impact. Patients are generally treated against the major sensitized allergen which does not warrant protection against cross-reactive allergens, leading to long and ineffective treatment regimens. For food allergies, patient guidelines rely on source avoidance, leading to dietary restrictions and reduced quality of life - in particular for those suffering from PFAS. To overcome these limitations, we introduce a novel allergy immunotherapy (AIT) approach utilizing consensus allergens and mRNA technology to achieve broader, safer, and faster desensitization in PFAS patients. We first designed a consensus allergen of orthologs of non-specific Lipid Transfer Proteins (cnsLTP-1) representing a broad spectrum of nsLTP allergens prevalent in food and pollen sources. CnsLTP-1 was delivered to naive BALB/c mice using mRNA-lipid nanoparticles (mRNA-LNP) as vehicle, or by a traditional protein formulation, to assess if it elicits broad protection against allergens from different sources. Immunization with both mRNA-LNP and protein formulations demonstrated that cnsLTP-1-specific IgGs could be induced, whilst the mRNA-LNP formulation notably avoided the induction of allergen-specific IgEs. The induced antibodies were capable of recognizing and binding to a variety of nsLTPs, and effectively blocked the binding of allergens by allergic patient serum IgEs. This study thus demonstrates that the presented AIT strategy, based on mRNA-LNP technology and consensus allergens, could find clinical utility by addressing the limitations of current AIT. Further development of this technology platform could pave the way for more effective and patient-friendly treatments for PFAS and other cross-reactive allergies.

bioengineering↗

Simultaneous analysis of pMHC binding and reactivity unveils virus-specific CD8 T cell immunity to a concise epitope set

Knowledge of widely recognized T-cell epitopes against common virus infections are vital for immune monitoring and characterization of relevant antigen-specific CD8 T cells and their antigen receptors. We therefore aimed to establish a concise and validated epitope panel for monitoring human virus-specific immunity complete with data on both prevalence of recognition and reactivity in humans. To achieve this, we first establish TCR downregulation, and loss of peptide major histocompatibility (pMHC) multimer-binding, as an early and sensitive marker of T cell reactivity after peptide stimulation. We next applied TCR downregulation in a high-throughput assay by monitoring binding, and loss of binding (i.e. reactivity), to libraries of DNA-barcode labelled pMHC multimers in paired unstimulated/stimulated samples. This novel method allowed us to access T-cell responses in 48 donors towards 929 epitopes recorded in the Immune Epitope Database (IEDB) encompassing 29 virus common infections and 25 different HLA alleles. This yielded a concise panel of 137 virus epitopes, many of which were underrepresented in the public domain, recognized by T cells in peripheral blood. 84% of these epitopes exhibited prevalent reactivity to peptide stimulation, which was associated with effector and long-term memory phenotypes. Conversely, non-reactive responses correlated with naive and immunosenescence phenotypes. This study represents the largest effort to unbiasedly assess T-cell recognition and reactivity to common virus infections in healthy individuals providing a minimal epitope panel for monitoring adaptive immune responses in humans. Significance StatementCD8 T-cell epitopes are widely available in public databases yet many are not recognized in the general population. Here we undertook an exhaustive screening process using "state-of-the-art" methods to assess both T-cell recognition and reactivity against common virus infections, which holds significant implications for shaping T-cell immunity and disease protection. We identify 137 commonly recognized epitopes from common virus infections to which T cell responses are expected to occur in human donors. Importantly, several of the verified epitopes were underreported in public databases compared to their observed prevalence of recognition and high cellular frequency making this an important reference dataset and resource for immunologists studying antigen-specific T cells across different immunopathologies and contexts including autoimmunity, infectious disease and cancer immunotherapy.

immunology↗

Engineered yeast cells simulating CD19+ cancers to control CAR T cell activation

Chimeric antigen receptor (CAR) T cells have become an established immunotherapy and show promising results for the treatment of hematological cancers. However, modulation of surface levels of the targeted antigen in cancer cells affects the quality and safety of CAR T cell therapy. Here we present the Synthetic Cellular Advanced Signal Adapter (SCASA) system, based on successful engineering of yeast to simulate cancer cells with tunable surface-antigen densities, as a tool for controlled activation of CAR T cell responses and assessment of antigen density effects. Specifically, we demonstrate I) controllable antigen-densities of CD19 on yeast using G protein-coupled receptors (GPCRs), II) a customizable system allowing choice of signal input and modular pathway engineering for precise fine-tuning of the output, III) synthetic cell-cell communication with CAR T cells and the application of CD19-displaying yeast in the characterization of CAR designs, and IV) more efficient and robust activational control of clinically-derived CAR T cells in comparison to the NALM6 cancer cell line. Based on this yeast-based antigen-presenting cell system, we envision efficient assessment of how varying antigen densities in cancer cells affect CAR T cell responses and ultimately support development of safer and better quality of personalized cancer therapies.

synthetic biology↗

Interferon-α promotes neo-antigen formation andpreferential HLA-B-restricted antigen presentation in pancreatic β-cells

Interferon (IFN)- is the earliest cytokine signature observed in individuals at risk for type 1 diabetes (T1D), but its effect on the repertoire of HLA Class I (HLA-I)-bound peptides presented by pancreatic {beta}-cells is unknown. Using immunopeptidomics, we characterized the peptide/HLA-I presentation in in-vitro resting and IFN--exposed {beta}-cells. IFN- increased HLA-I expression and peptide presentation, including neo-sequences derived from alternative mRNA splicing, post-translational modifications - notably glutathionylation - and protein cis-splicing. This antigenic landscape relied on processing by both the constitutive and immune proteasome. The resting {beta}-cell immunopeptidome was dominated by HLA-A-restricted ligands. However, IFN- only marginally upregulated HLA-A and largely favored HLA-B, translating into a major increase in HLA-B-restricted peptides and into an increased activation of HLA-B-restricted vs. HLA-A-restricted CD8+ T-cells. A preferential HLA-B hyper-expression was also observed in the islets of T1D vs. non-diabetic donors, and we identified islet-infiltrating CD8+ T-cells from T1D donors reactive to HLA-B-restricted granule peptides. Thus, the inflammatory milieu of insulitis may skew the autoimmune response toward epitopes presented by HLA-B, hence recruiting a distinct T-cell repertoire that may be relevant to T1D pathogenesis.

immunology↗

ATRAP - Accurate T cell Receptor Antigen Pairing through data-driven filtering of sequencing information from single-cells

Novel single-cell based technologies hold the promise of matching T cell receptor (TCR) sequences with their cognate peptide-MHC recognition motif in a high-throughput manner. Parallel capture of TCR transcripts and peptide-MHC is enabled through the use of reagents labeled with DNA barcodes. However, analysis and annotation of such single-cell sequencing (SCseq) data is challenged by dropout, random noise, and other technical artifacts that must be carefully handled in the downstream processing steps. We here propose a rational, data-driven method termed ATRAP (Accurate T cell Receptor Antigen Paring) to deal with these challenges, filtering away likely artifacts, and enable the generation of large sets of TCR-pMHC sequence data with a high degree of specificity and sensitivity, thus outputting the most likely pMHC target per T cell. We have validated this approach across 10 different virus-specific T cell responses in 16 healthy donors. Across these samples we have identified up to 1494 high-confident TCR-pMHC pairs derived from 4135 single-cells.

immunology↗

Three-doses of BNT162b2 COVID-19 mRNA vaccine establishes long-lasting CD8+ T cell immunity in CLL and MDS patients

Patients with hematological malignancies are prioritized for COVID-19 vaccine due to their high risk for severe SARS-CoV-2 infection related disease and mortality. To understand T cell immunity, its long-term persistence, and correlation with antibody response, we evaluated the BNT162b2 COVID-19 mRNA vaccine-specific immune response in chronic lymphocytic leukemia (CLL) and myeloid dysplastic syndrome (MDS) patients. Longitudinal analysis of CD8+ T cells using DNA-barcoded peptide-MHC multimers covering the full SARS-CoV-2 Spike-protein (415 peptides) showed vaccine-specific T cell activation and persistence of memory T cells up to six months post-vaccination. Surprisingly, a higher frequency of vaccine-induced antigen-specific CD8+ T cell was observed in the patient group compared to a healthy donor group. Furthermore, and importantly, immunization with the second booster dose significantly increased the frequency of antigen-specific CD8+ T cells as well as the total number of T cell specificities. Altogether 59 BNT162b2 vaccine-derived immunogenic epitopes were identified, of which 23 established long-term CD8+ T cell memory response with a strong immunodominance for NYNYLYRLF (HLA-A24:02) and YLQPRTFLL (HLA-A02:01) epitopes. In summary, we mapped the vaccine-induced antigen-specific CD8+ T cells and showed a booster-specific activation and enrichment of memory T cells that could be important for long-term disease protection in this patient group. Key PointsO_LICOVID-19 mRNA vaccine induced an early and persistent activation of antigen-specific CD8+ T cells in this patient group. C_LIO_LIVaccination with a booster dose is required to maintain vaccine-specific CD8+ T cells. C_LI

immunology↗

SARS-CoV-2 genome-wide mapping of CD8 T cell recognition reveals strong immunodominance and substantial CD8 T cell activation in COVID-19 patients

To understand the CD8+ T cell immunity related to viral protection and disease severity in COVID-19, we evaluated the complete SARS-CoV-2 genome (3141 MHC-I binding peptides) to identify immunogenic T cell epitopes, and determine the level of CD8+ T cell involvement using DNA-barcoded peptide-major histocompatibility complex (pMHC) multimers. COVID-19 patients showed strong T cell responses, with up to 25% of all CD8+ lymphocytes specific to SARS-CoV-2-derived immunodominant epitopes, derived from ORF1 (open reading frame 1), ORF3, and Nucleocapsid (N) protein. A strong signature of T cell activation was observed in COVID-19 patients, while no T cell activation was seen in the non-exposed and high exposure risk healthy donors. Interestingly, patients with severe disease displayed the largest T cell populations with a strong activation profile. These results will have important implications for understanding the T cell immunity to SARS-CoV-2 infection, and how T cell immunity might influence disease development.

immunology↗

The retinoic acid receptor drives neuroinflammation and fine tunes the homeostasis of interleukin-17-producing T cells

The vitamin A metabolite retinoic acid (RA) is critical for the maturation and function of the immune system, however, our knowledge regarding its role in gamma delta ({gamma}{delta}) T cells is limited. By specifically inactivating the RA receptor alpha (RAR) in type 3 lymphocytes and using a combination of fetal thymic organ cultures and single-cell RNA-sequencing we found that RA strengthened TCR signaling to limit the embryonic development of interleukin(IL)-17-producing {gamma}{delta} T cells ({gamma}{delta}T17), while at the same time it promoted their survival after birth. In adult mice, RA imposed a multi-level transcriptional program allowing {gamma}{delta}T17 cells to become activated, survive and sense interferon. Consequently, cells with inactive RAR responded poorly to immunization and produced low level of cytokines leading to near disease resistance in the experimental autoimmune encephalomyelitis model. Finally, RA was required for optimal expression of the 4{beta}1 integrin and {gamma}{delta}T17 cell infiltration to the brain. Collectively, these studies suggest that by acting at various stages during the lifetime of {gamma}{delta} T cells, RA supports their normal development, their survival and their ability to respond to inflammatory stimuli.

immunology↗

NetTCR: sequence-based prediction of TCR binding to peptide-MHC complexes using convolutional neural networks

Predicting epitopes recognized by cytotoxic T cells has been a long standing challenge within the field of immuno- and bioinformatics. While reliable predictions of peptide binding are available for most Major Histocompatibility Complex class I (MHCI) alleles, prediction models of T cell receptor (TCR) interactions with MHC class I-peptide complexes remain poor due to the limited amount of available training data. Recent next generation sequencing projects have however generated a considerable amount of data relating TCR sequences with their cognate HLA-peptide complex target. Here, we utilize such data to train a sequence-based predictor of the interaction between TCRs and peptides presented by the most common human MHCI allele, HLA-A*02:01. Our model is based on convolutional neural networks, which are especially designed to meet the challenges posed by the large length variations of TCRs. We show that such a sequence-based model allows for the identification of TCRs binding a given cognate peptide-MHC target out of a large pool of non-binding TCRs.

bioinformatics↗