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Biology subjects

Chou, H.

Publications and source records attributed to Chou, H..

7 recordsLinked to original sources

Generation of an induced pluripotent stem cell line from a patient with immune checkpoint inhibitor-induced myocarditis and concurrent type I diabetes

Immune checkpoint inhibitor-induced myocarditis (ICIM) is a severe immune-related adverse event with heterogeneous clinical presentations and potential genetic susceptibility. Here, we established a human induced pluripotent stem cell (iPSC) line from an ICIM patient with an HLA-type distinct from previously reported line, who developed concurrent type I diabetes following ICI treatment. This line exhibited typical morphology, normal female karyotype, pluripotency, trilineage differentiation into all three germ layers, Sendai virus clearance, and no mycoplasma contamination. Given the fulminant nature and diverse clinical presentations of ICIM, expanding the repertoire of iPSC lines are critical for investigating ICIM heterogeneity and its underlying mechanisms.

developmental biology↗

Generation of three induced pluripotent stem cell lines from an immune checkpoint inhibitor-induced myocarditis patient and controls

Immune checkpoint inhibitor-associated myocarditis (ICIM) is an uncommon but potentially fatal inflammatory heart disease triggered by cancer immunotherapy, with up to 40% mortality. The underlying mechanisms are still elusive, partly due to the lack of appropriate human disease models. Here, we report the generation of three induced pluripotent stem cell (iPSC) lines derived from an ICIM patient, an ICI-treated patient without myocarditis, and a healthy donor. These lines exhibit typical pluripotent stem cell morphology, express pluripotency markers, maintain normal karyotypes, and differentiate into derivatives of the three germ layers, providing a valuable platform for mechanistic studies and therapeutic discovery.

Developmental Biology↗

Development of ferret immune repertoire reference resources and single-cell-based high-throughput profiling assays

Domestic ferrets (Mustela putorius furo) are important for modeling human respiratory diseases. However, ferret B and T cell receptors have not been completely identified or annotated, limiting immune repertoire studies. Here we performed long read transcriptome sequencing of ferret splenocyte and lymph node samples to obtain over 120,000 high-quality full-length immunoglobin (Ig) and T cell receptor (TCR) transcripts. We constructed a complete reference set of the constant regions of ferret Ig and TCR isotypes and chain types. We also systematically annotated germline Ig and TCR variable (V), diversity (D), joining (J), and constant (C) genes on a recent ferret reference genome assembly. We designed new ferret-specific immune repertoire profiling assays by targeting positions in constant regions without allelic diversity across 11 ferret genome assemblies, and experimentally validated them using a commercially compatible single-cell-based platform. These improved resources and assays will enable future studies to fully capture ferret immune repertoire diversity.

genomics↗

Human long noncoding RNA, VILMIR, is induced by major respiratory viral infections and modulates the host interferon response

Long noncoding RNAs (lncRNAs) are a newer class of noncoding transcripts identified as key regulators of biological processes. Here we aimed to identify novel lncRNA targets that play critical roles in major human respiratory viral infections by systematically mining large-scale transcriptomic datasets. Using bulk RNA-sequencing (RNA-seq) analysis, we identified a previously uncharacterized lncRNA, named virus inducible lncRNA modulator of interferon response (VILMIR), that was consistently upregulated after in vitro influenza infection across multiple human epithelial cell lines and influenza A virus subtypes. VILMIR was also upregulated after SARS-CoV-2 and RSV infections in vitro. We experimentally confirmed the response of VILMIR to influenza infection and interferon-beta (IFN-{beta}) treatment in the A549 human epithelial cell line and found the expression of VILMIR was robustly induced by IFN-{beta} treatment in a dose and time-specific manner. Single cell RNA-seq analysis of bronchoalveolar lavage fluid (BALF) samples from COVID-19 patients uncovered that VILMIR was upregulated across various cell types including at least five immune cells. The upregulation of VILMIR in immune cells was further confirmed in the human T cell and monocyte cell lines, SUP-T1 and THP-1, after IFN-{beta} treatment. Finally, we found that knockdown of VILMIR expression reduced the magnitude of host transcriptional responses to IFN-{beta} treatment in A549 cells. Together, our results show that VILMIR is a novel interferon-stimulated gene (ISG) that regulates the host interferon response and may be a potential therapeutic target for human respiratory viral infections upon further mechanistic investigation. IMPORTANCEIdentifying host factors that regulate the immune response to human respiratory viral infection is critical to developing new therapeutics. Human long noncoding RNAs (lncRNAs) have been found to play key regulatory roles during biological processes, however the majority of lncRNA functions within the host antiviral response remain unknown. In this study, we identified that a previously uncharacterized lncRNA, VILMIR, is upregulated after major respiratory viral infections including influenza, SARS-CoV-2, and RSV. We demonstrated that VILMIR is an interferon-stimulated gene that is upregulated after interferon-beta (IFN-{beta}) in several human cell types. We also found that knockdown of VILMIR reduced the magnitude of host transcriptional responses to IFN-{beta} treatment in human epithelial cells. Our results reveal that VILMIR regulates the host interferon response and may present a new therapeutic target during human respiratory viral infections.

immunology↗

A Novel Therapeutic Approach using CXCR3 Blockade to Treat Immune Checkpoint Inhibitor-mediated Myocarditis

BackgroundImmune checkpoint inhibitors (ICIs) are successful in treating many cancers but may cause immune-related adverse events. ICI-mediated myocarditis has a high fatality rate of up to 40%, with severe cardiovascular consequences. Targeted therapies for ICI myocarditis are currently lacking. MethodsWe used a genetic mouse model of PD-1 deletion (MRL/Pdcd1-/-) along with a novel drug-treated ICI myocarditis mouse model to recapitulate the disease phenotype. We performed single-cell RNA-sequencing (scRNAseq), single-cell T-cell receptor sequencing (scTCR-seq), and cellular indexing of transcriptomes and epitopes (CITE-seq) on immune cells isolated from MRL and MRL/Pdcd1-/- mice at serial timepoints. We assessed the impact of macrophage deletion in MRL/Pdcd1-/- mice, then inhibited CXC chemokine receptor 3 (CXCR3) in ICI-treated mice to assess therapeutic effect on myocarditis phenotype. Furthermore, we delineated functional effects of CXCR3 blockade on T-cell and macrophage interactions in a transwell assay. We then correlated the results in human single-cell multi-omics data from blood and heart biopsy data from patients with ICI myocarditis. ResultsSingle-cell multi-omics demonstrated expansion of CXCL9/10+CCR2+ macrophages and CXCR3hi CD8+ effector T-lymphocytes in the hearts of MRL/Pdcd1-/- mice correlating with onset of myocarditis development. Both depletion of CXCL9/10+CCR2+ macrophages and CXCR3 blockade respectively led to decreased CXCR3hiCD8+ T-cell infiltration into the heart and significantly improved survival. A transwell assay showed that selective blockade of CXCR3 and its ligand, CXCL10 decreased CD8+ T-cell migration towards macrophages, implicating this interaction in T-cell cardiotropism towards cardiac macrophages. Cardiac biopsies from patients with confirmed ICI myocarditis demonstrated infiltrating CXCR3+ lymphocytes and CXCL9+/CXCL10+ macrophages. Both mouse cardiac immune cells and patient peripheral blood immune cells revealed expanded TCRs correlating with CXCR3hi CD8+ T-cells in ICI myocarditis samples. ConclusionsThese findings bring forth the CXCR3-CXCL9/10 axis as an attractive therapeutic target for ICI myocarditis treatment, and more broadly, as a druggable pathway in cardiac inflammation.

cell biology↗

Tunable PhenoCycler Imaging of the Murine Pre-Clinical Tumour Microenvironments

The tumour microenvironment (TME) consists of tumour-supportive immune cells, endothelial cells, and fibroblasts. PhenoCycler, a high-plex single cell imaging platform, is used to characterize the complexity of the TME. Here, we used PhenoCycler to spatially resolve the TME of 8 routinely employed pre-clinical models of lymphoma, breast cancer, and melanoma. Our data reveal distinct TMEs in the different cancer models that were imaged, and show that cell-cell contacts differ depending on the tumour type examined. For instance, we found that the immune infiltration in a murine model of melanoma is altered in cellular organization in melanomas that become resistant to PD-1 therapy, with depletions in a number of cell-cell interactions. Furthermore, we provide detailed pipelines for the conjugation of antibodies that are optimized for PhenoCycler staining of murine FFPE tissues specifically, alongside open-source data analysis procedures. Overall, this is a valuable resource study seamlessly adaptable to any field of research involving murine models.

cancer biology↗

Single cell based high-throughput Ig and TCR repertoire sequencing analysis in rhesus macaques

Recent advancements in microfluidics and high-throughput sequencing technologies have enabled recovery of paired heavy- and light-chains of immunoglobulins (Ig) and VDJ- and VJ-chains of T cell receptors (TCR) from thousands of single cells simultaneously in humans and mice. Despite rhesus macaques being one of the most well-studied model organisms for the human adaptive immune response, high-throughput single cell immune repertoire sequencing assays are not yet available due to the complexity of these polyclonal receptors. Here we employed custom primers that capture all known rhesus macaque Ig and TCR isotypes and chains that are fully compatible with a commercial solution for single cell immune repertoire profiling. Using these rhesus specific assays, we sequenced Ig and TCR repertoires in over 60,000 cells from cryopreserved rhesus PBMC, splenocytes, and FACS-sorted B and T cells. We were able to recover every Ig isotype and TCR chain, measure clonal expansion in proliferating T cells, and pair Ig and TCR repertoires with gene expression profiles of the same single cells. Our results establish the ability to perform high-throughput immune repertoire analysis in rhesus macaques at the single cell level.

immunology↗