Pathological TNFR1 Expressing CD4+ T-cells are Critical for HF progression

 描述(申请人提供)：项目总结候选人。我的长期目标是在转化性心血管研究中获得终身教职，成为一名独立的研究员。为了实现这一目标，我制定了一项多方面的职业发展计划，其中包括：i)通过高级研究生课程进行高级学术培训；ii)通过参加与补助金和手稿相关的研讨会来发展我的写作技能；iii)建立合作研究网络；iv)出席并在国家会议上发言；v)努力发表有影响力的论文。我打算在K99阶段参与这些活动，这样我就可以有效地过渡到R0阶段，独立开发和管理我自己的研究计划和研究提案，以提交独立的拨款。我在基础科学方面的培训将侧重于获得在心脏综合生理学(超声心动图和压力-容量)和T细胞信号机制(肿瘤坏死因子-肿瘤坏死因子受体1轴)研究方面运用先进技术的能力，目的是最终整合这些不同的领域，建立一种独特而新颖的研究范式，为我的独立学术生涯奠定基础。从长远来看，我设想将我在药物递送、药理学、毒理学、药代动力学和心血管疾病方面的多学科培训结合起来，以了解心力衰竭的病理生理学，并设计出新的翻译策略。凭借我独特的背景和这个奖项的支持，我的目标是在学术界和产业界之间发展有效的合作，成功地将我的研究成果转化为临床。环境为了支持我的长期职业目标，我的指导团队包括世界知名的临床科学家Sumanth D.Prabhu博士和Louis J.Dell‘Italia博士，他们积极从事心力衰竭的研究工作；Casey T Weaver博士，医学博士，T细胞生物学专家；Martin E.Young博士，心脏新陈代谢/昼夜节律方面的专家。这种多学科的研究人员组合为我提供了一个优秀而独特的培训环境，有助于培养一名成功的转化型心血管研究人员。普拉布博士和韦弗博士的实验室配备了成功实施拟议研究所需的所有资源、设备和方法。UAB的综合心血管中心(CCVC)由几名临床科学家和基础研究人员组成，他们拥有不同学科的专业知识，包括生理学、病理学、分子生物学、生物化学和成像。这种多维的研究环境将极大地促进我作为一名学术科学家和导师的发展。这一良好的研究环境，通过UAB提供的尖端核心设施，将为成功完成这项提案和我的培训提供至关重要的支持。研究。慢性炎症和免疫反应是心肌梗死后心力衰竭(HF)的重要组成部分，决定着随后的心肌梗死愈合和左心室(LV)重构。几种促炎细胞因子水平升高的鉴定导致了针对它们的中和治疗努力，这在临床研究中失败了。事实上，细胞因子水平升高不是潜在病理的直接原因，而是激活的炎症反应的结果，这一事实强调了炎症和免疫反应在心肌梗死(MI)后心脏修复中更复杂的作用。在这方面，最近的研究 与CD4-/-小鼠的研究表明，在急性期，CD4+T细胞通过促进新生血管和减少纤维化组织的形成，在缺血心脏和后肢肌肉的愈合中发挥关键作用。然而，全球基因敲除小鼠模型(如CD4-/-)未能考虑从急性到慢性心衰进展过程中的时空变化。尽管如此，能够证明CD4+T细胞在慢性心力衰竭中的作用的临床相关性尚不清楚。在持续性组织损伤中，如心衰，先天免疫细胞作为抗原提呈细胞，激活效应T细胞和持久记忆T细胞的分化和克隆性增殖。急性期单核细胞和巨噬细胞的强烈激活也意味着T细胞的激活。事实上，我们的初步结果清楚地表明，在慢性心力衰竭期间，T细胞在缺血心肌、循环和重塑的脾中的激活和扩张增强。我们的初步结果还表明，T细胞表型的全球时空变化，是由肿瘤坏死因子α和肿瘤坏死因子受体1的表达增强所介导的，这两种经典的促炎信号分子已被证明与临床上的心衰严重程度和心功能不全相关。因此，这意味着T细胞在缺血心脏中发挥着复杂的双相效应，这使我们假设在慢性心力衰竭过程中，促炎症表型转换为TNFR1表达，从病理上改变了CD4+T细胞，促进了心脏组织损伤和病理性左室重构，并促进了心力衰竭疾病的进展。重要的是，这些都是免疫调节的关键细胞靶点。我们将通过以下方法来验证这一假说：i)描述全球CD4+T细胞在心力衰竭中的全球转运和促炎表型；ii)通过可逆性和特异性地去除转基因CD4-DTR小鼠中的病理T细胞，确定CD4+T细胞在慢性心力衰竭左室重构和慢性心力衰竭中的病理生理学作用；以及iii)通过过继转移TNFR1+或TNFR1-CD4+T细胞来确定TNFR1+CD4+T细胞对于慢性心力衰竭患者的不利左室重构是否既是必要的也是充分的。

 DESCRIPTION (provided by applicant):Project Summary Candidate. My long term goal is to secure a tenure track faculty position as an independent investigator in translational cardiovascular research. To achieve this aim, I have devised a multi-faceted career development plan with several strategic short term goals that include i) advanced academic training through upper graduate level courses, ii) develop my writing skills by participating in grant and manuscript related workshops, iii) networking for collaborative research, iv) attend and present at national meetings, and v) work to publish high impact papers. I intend to participate in these activities during the K99 phase so that I can effectively transition to the R0 phase to independently develop and manage my own research program and research proposals to submit independent grants. My training in basic science will focus on acquiring abilities to carry out advanced techniques in the study of integrative cardiac physiology (echocardiography and pressure-volume) and T-cell signaling mechanisms (TNF-TNFR1 axis) with the aim to ultimately integrate these diverse fields to establish a distinct and novel researc paradigm which will lay the foundation for my independent academic career. In the long term, I envision incorporating my multi-disciplinary training in drug delivery, pharmacology, toxicology, pharmacokinetics and cardiovascular diseases to understand pathophysiology of heart failure and devise novel translational strategies. With my unique background and support from this award, I aim to develop effective collaborations between academia and industry to successfully transition my research findings to the clinic. Environment. To support my long term career goals, I have included world renowned clinician scientists; Dr. Sumanth D. Prabhu, MD, and Dr. Louis J. Dell'Italia, MD, actively working in heart failure; Dr. Casey T Weaver, MD, expert in T-cell biology and Dr. Martin E. Young, PhD, expert in cardiac metabolism/circadian rhythms, in my mentoring team. This multi-disciplinary combination of investigators provides me an excellent and unique training environment conducive to creating a successful translational cardiovascular investigator. Dr. Prabhu and Dr. Weaver's laboratories are well equipped with all the resources, equipment, and methodologies required for successful execution of proposed studies. The Comprehensive Cardiovascular Center (CCVC) at UAB consists of several clinician scientists and basic research investigators with expertise in diverse disciplines including physiology, pathology, molecular biology, biochemistry, and imaging. This multidimensional research environment will significantly facilitate my development as an academic scientist and as a mentor. This excellent research environment, cutting edge core facilities available through UAB will provide crucial support for the successful completion of this proposal and my training. Research. Chronic inflammatory and immune responses are an integral part of post-infarct heart failure (HF) and dictate subsequent infarct healing and left ventricular (LV) remodeling. The identification of augmented levels of several pro-inflammatory cytokines resulted in therapeutic efforts directed toward their neutralization, which failed in clinical studies. The fact that increased cytokine levels is not the proximate cause of underlying pathology but is the result of activated inflammatory responses emphasizes a more complex role of inflammatory and immune reactions in cardiac repair after myocardial infarction (MI). In this regard, recent studies with CD4-/- mice indicated that during the acute phase CD4+ T-cells play a crucial role in the healing of ischemic hearts and hind-limb muscles by promoting neovascularization and reducing fibrotic tissue formation. However, global knockout mouse models (such as CD4-/-) fail to consider spatio-temporal alterations as we see during progression from acute to chronic HF. Nonetheless, the clinical correlates that can demonstrate the role of CD4+ T-cells during chronic HF are not known. During persistent tissue injury such as in HF, innate immune cells act as antigen presenting cells to activate differentiation and clonal expansion of effector T-cells and long lasting memory T-cells. Intense activation of monocytes and macrophages during the acute phase thus implies activation of T-cells also. Indeed, our preliminary results clearly show heightened activation and expansion of T-cells in the ischemic myocardium, circulation, and remodeled spleen during chronic HF. Our preliminary results also suggest global spatio-temporal alterations in T-cell phenotype, mediated by enhanced expression of TNFα and TNFR1, classical pro-inflammatory signaling molecules that have been shown to correlate with HF severity and cardiac dysfunction clinically. This, therefore, implies that T-cells exert a complex biphasic effect in the ischemic heart leading us to hypothesize that a pro-inflammatory phenotypic switch to TNFR1 expression during chronic HF pathologically alters CD4+ T-cells to promote cardiac tissue injury and pathological LV remodeling, and HF disease progression. Importantly, these are key cellular targets for immunomodulation. We will test this hypothesis by i) delineating global CD4+ T-cell trafficking and pro-inflammatory phenotype in HF, ii) establishing the pathophysiologic role of CD4+ T-cells in LV remodeling and chronic HF by reversibly and specifically ablating pathological T-cells in transgenic CD4-DTR mice, and iii) defining whether TNFR1+ CD4+ T-cells are both necessary and sufficient for adverse LV remodeling in chronic HF by adoptive transfer studies of TNFR1+or TNFR1- CD4+ T-cells.