ABO and Immunogenetic Variation in the Pathogenesis of Heparin-Induced Thrombocytopenia

肝素诱导的血小板减少症发病机制中的 ABO 和免疫遗传学变异

基本信息

批准号：
10439313
负责人：
Jason Hansen Karnes
金额：
$ 45.73万
依托单位：
UNIVERSITY OF ARIZONA
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-07-01 至 2026-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10439313
关键词：
ABO blood group system Acute Address Adverse reactions Affect Alleles Antibodies Antibody Formation Biological Biological Assay Biological Markers Blood Cardiovascular Diseases Cells Cellular Indexing of Transcriptomes and Epitopes by Sequencing Clinical Computerized Medical Record Coupled DNA Data Detection Family Genes Genetic Genetic Determinism Genetic Drift Genomics Genotype Guide RNA HLA Antigens Helper-Inducer T-Lymphocyte Heparin Immune Immunogenetics Immunogenomics Incidence Incubated Individual Knowledge Life Measures Mediating Membrane Proteins Mission Modeling Molecular Odds Ratio Outcome PF4 Gene Pathogenesis Pathogenicity Pathology Patients Phase Population Population Heterogeneity Prevention Prevention strategy Preventive Proliferating Public Health Publishing RNA Reaction Research Resolution Risk Role Sample Size Sampling Staphylococcal Enterotoxin B T-Cell Activation Pathway T-Cell Proliferation T-Cell Receptor Testing Th2 Cells Thromboembolism United States National Institutes of Health Variant Work adverse drug reaction base biobank blood group clinical practice clinical translation cohort deep sequencing diagnostic strategy direct application experimental study genome wide association study genome-wide genomic variation heparin-induced thrombocytopenia immunopathology innovation insight mortality overexpression programs racial diversity transcriptome transcriptome sequencing

项目摘要

ABSTRACT Despite decades of research into the immunopathology of heparin-induced thrombocytopenia (HIT), an unpredictable, life-threatening, immune-mediated adverse reaction to heparin treatment, a fundamental knowledge gap regarding the cause of HIT remains. The inability to predict HIT represents a considerable liability associated with heparin, which is given to 12 million individuals or one third of all hospitalized patients every year. Because the exact cellular and molecular mechanisms underlying HIT have yet to be identified, including intrinsic immune cell roles and the difference between pathogenic and non-pathogenic antibodies, there is an essential need to apply alternative approaches to understand the biological basis for HIT and to identify clinically implementable biomarkers. The PI’s central hypothesis is that immunogenomic variation impacts HIT pathogenesis and can be used to differentiate non-pathogenic and pathogenic PF4/heparin antibodies, which are produced by immune cell populations intrinsic to HIT. Based on strong preliminary data that constitute the largest genome-wide association study (GWAS) for HIT, the working hypothesis is that the presence of the HLA-DRB3*01:01 allele combined with proliferating Vβ 5.1 family T-Cell receptor (TCR) clonotypes in Th2 cells predisposes patients to pathogenic PF4/heparin antibody production, and these antibodies result in high HIT risk in patients with the ABO O blood group. We will pursue three Specific Aims (SAs) to test the central hypothesis: (SA1) Determine the role of ABO variation in HIT; (SA2) Determine the influence of genomic variation on PF4/heparin antibody production; and (SA3) Identify intrinsic immune cell involvement in HIT. In SA #1, deep ABO sequencing data will be utilized in our large cohort of functional assay-confirmed HIT patients to elucidate the role of ABO variability in HIT. In SA #2, we will perform several GWAS to determine genetic influences of PF4/heparin antibody production, including diverse populations, and differentiate genetic influences on pathogenic versus non-pathogenic antibodies. In SA#3, we will sample paired cell populations during the acute phase of HIT and after HIT resolution and conduct focused single cell (sc) studies to determine proliferation of TCR clonotypes and activated cell populations using sc-RNA-TCR-CITE-seq. Our studies overcome major limitations of previous genomic studies of HIT by incorporating large, diverse cohorts, a PF4/heparin antibody- positive case group, and functional assay confirmation of HIT cases. This work is technically and conceptually innovative as it leverages a sc-RNA-TCR-CITE-seq approach, utilizes large, unique HIT cohorts, and advances an original model of HIT immunopathogenesis. We expect to provide mechanistic insights into HIT pathology and advance a framework for clinical translation of HIT biomarkers with direct application to other adverse drug reactions. The proposed studies leverage large-scale biological data to distinguish patients pre-disposed to HIT, potentially shifting clinical practice from treatment to prevention through biomarker-guided heparin treatment.

抽象的尽管对肝素诱导的血小板减少症 (HIT) 的免疫病理学进行了数十年的研究，但肝素治疗的不可预测的、危及生命的、免疫介导的不良反应是肝素治疗的一个根本原因关于 HIT 原因的知识差距仍然存在，无法预测 HIT 是一个相当大的责任。与肝素有关，每年有 1200 万人（即所有住院患者的三分之一）接受肝素注射因为 HIT 的确切细胞和分子机制尚未确定，包括。内在免疫细胞的作用以及致病性和非致病性抗体之间的差异，有一个迫切需要应用替代方法来了解 HIT 的生物学基础并在临床上进行识别 PI 的中心假设是免疫基因组变异影响 HIT。发病机制，可用于区分非致病性和致病性 PF4/肝素抗体，由 HIT 固有的免疫细胞群产生，基于构成 HIT 的强有力的初步数据。 HIT 最大的全基因组关联研究 (GWAS)，工作假设是 HLA-DRB3*01:01 等位基因与 Th2 细胞中增殖的 Vβ 5.1 家族 T 细胞受体 (TCR) 克隆型相结合使患者容易产生致病性 PF4/肝素抗体，而这些抗体会导致高 HIT 风险在 ABO O 血型患者中，我们将追求三个特定目标 (SA) 来检验中心假设： (SA1) 确定 ABO 变异在 HIT 中的作用； (SA2) 确定基因组变异对 HIT 的影响； PF4/肝素抗体的产生；以及 (SA3) 识别 HIT 中的内在免疫细胞参与，在 SA #1 中，深层。 ABO 测序数据将用于我们大量经功能测定证实的 HIT 患者，以阐明 ABO 变异在 HIT 中的作用在 SA #2 中，我们将进行几次 GWAS 以确定 ABO 变异的遗传影响。 PF4/肝素抗体的产生，包括不同的人群，并区分遗传对在 SA#3 中，我们将在急性期对配对细胞群进行采样。 HIT 阶段和 HIT 解决后进行重点单细胞 (sc) 研究以确定使用 sc-RNA-TCR-CITE-seq 进行 TCR 克隆型和激活的细胞群研究通过纳入大量、多样化的队列，PF4/肝素抗体，克服了之前 HIT 基因组研究的局限性阳性病例组，以及 HIT 病例的功能测定确认，这项工作在技术上和概念上都是如此。创新性，因为它利用 sc-RNA-TCR-CITE-seq 方法，利用大型、独特的 HIT 队列，并取得进展我们期望为 HIT 病理学提供机制见解。并推进 HIT 生物标志物临床转化框架，直接应用于其他不良药物拟议的研究利用大规模生物数据来区分易患 HIT 的患者，通过生物标志物引导的肝素治疗，有可能将临床实践从治疗转向预防。