Novel Inhibitors for Temporal Modulation of T-Lymphocytes during Chronic Heart Failure

项目摘要 炎症免疫反应预示着心肌梗死(MI)后心脏的愈合，并且是暂时的 调节以启动伤口愈合和疤痕形成。最近的研究表明，除了 心肌梗死(MI)后即刻，循环、脾和心脏炎症细胞(单核细胞， 巨噬细胞和T淋巴细胞)即使在MI(慢性心力衰竭)后8周也增加，并促进 病理性左心室重构。此外，我们和其他人已经表明，特定的 慢性心力衰竭时的细胞类型，包括单核/巨噬细胞或T细胞，可钝化左室重构并防止 心功能进行性下降，提示免疫细胞在该病中起关键作用。这些 这些发现强调了确定特定的分子机制的必要性，这些机制可以有针对性地抑制 病理性免疫激活用于治疗性免疫调节。 最近的研究表明，CD4+T细胞对于有效的愈合、新生血管和 检查心肌梗死时的过度纤维化。然而，全球基因敲除小鼠模型(如CD4-/-)未能考虑 从急性心肌梗死到慢性心力衰竭进展过程中的时空变化。事实上，我们之前的 研究表明，在慢性心力衰竭过程中，CD4+T细胞发生表型转换，促进LV 心肌梗死后4-8周抗原依赖方式的重构和它们的耗竭导致进行性钝化 心脏功能不全。尽管如此，调节这一转变的分子签名从保护性 心梗期间到慢性心力衰竭期间的病理改变尚不清楚。心脏CD4+T细胞的RNA测序 从雄性小鼠衰竭的心脏中进行流动分类，我们发现，与MI相反，T细胞在HF期间被激活 具有上调的雌激素受体(ER)α信号。由于ERα效应与ERβ激活相反，我们 确定了一种新的ERβ激动剂(OSU-ERB-012)。我们的初步数据显示，OSU-ERB-012具有很高的 有效抑制抗CD3/CD28(T细胞受体)介导的T细胞增殖和前T细胞的表达 炎性细胞因子，体外和体内。此外，在10 mg/kg剂量下，OSU-Erb-012显著钝化 心肌梗死后4-8周给药后左室重构和心力衰竭进展提示其治疗作用 功效。因此，我们假设OSU-Erb-012选择性地抑制抗原激活的病理性CD4+ 临床可翻译剂量的T细胞改善左室重构和进展性心功能不全 ER-β激动剂可作为选择性免疫调节药物。我们将对此进行测试 假说：i)描述OSU-Erb-012改善左心室重构的剂量依赖效应，ii)测试 OSU-ERB-012的保护作用是否通过T细胞特异性ERβ激动剂介导，以及 确定OSU-Erb-012对心肌细胞功能和心脏生理的影响。

Project Summary Inflammatory immune responses dictate cardiac healing post-myocardial infarction (MI) and are temporally regulated to initiate wound-healing and scar formation. Recent studies have shown that, in addition to immediately after myocardial infarction (MI), circulating, splenic and cardiac inflammatory cells (monocytes, macrophages, and T-lymphocytes) are augmented even at 8-weeks post-MI (chronic HF), and promote pathological left ventricular (LV) remodeling. Moreover, we and others have shown that depletion of specific cell types, including monocytes/macrophages or T-cells during chronic HF blunts LV remodeling and prevents progressive decline in cardiac function, suggesting a critical role of immune cells in this disease. These findings underscore the necessity for identifying specific molecular mechanisms that can be targeted to restrain pathological immune activation for therapeutic immune-modulation. Recent studies have shown that CD4+ T-cells are obligatory for efficient healing, neovascularization, and to check excessive fibrosis during MI. However, global knockout mouse models (such as CD4-/-) fail to consider spatio-temporal alterations that we see during progression from acute-MI to chronic HF. Indeed, our previous studies showed that CD4+ T-cells undergo a phenotypic shift specifically during chronic HF, promote LV remodeling in an antigen-dependent manner, and their depletion from 4 to 8 weeks post-MI blunts progressive cardiac dysfunction. Nonetheless, the molecular signatures that mediate this transition from being protective during MI to pathological during chronic HF are not known. Using RNA sequencing on cardiac CD4+ T-cells flow-sorted from the failing hearts of male mice, we showed that, as opposed to MI, T-cells activated during HF possess upregulated estrogen receptor (ER) α signaling. Since ERα effects are opposed by ERβ activation, we identified a novel ERβ agonistic drug (OSU-ERb-012). Our preliminary data show that OSU-ERb-012 is highly efficacious at inhibiting anti-CD3/CD28 (T-cell receptor) mediated T-cell proliferation and expression of pro- inflammatory cytokines, ex-vivo and in-vivo. Moreover, at 10 mg/kg dose OSU-ERb-012 significantly blunted LV remodeling and HF progression when administered from 4 to 8 weeks post-MI suggesting its therapeutic efficacy. Thus, we hypothesize that OSU-ERb-012 selectively inhibits antigenically activated pathological CD4+ T-cells at clinically translatable doses, ameliorate LV remodeling and progressive cardiac dysfunction during chronic HF, and that ERβ agonists could be used as selective immuno-modulatory drugs. We will test this hypothesis by i) delineating dose-dependent effects of OSU-ERb-012 in ameliorating LV remodeling, ii) testing whether the protective effects of OSU-ERb-012 are mediated through T-cell specific ERβ agonism, and iii) identify effects of OSU-ERb-012 on cardiomyocyte function and cardiac physiology.