BACKGROUND Excess fibrotic remodeling causes cardiac dysfunction in ischemic heart disease, driven by MAP (mitogen-activated protein) kinase-dependent TGF-ß1 (transforming growth factor-ß1) activation by coagulation signaling of myeloid cells. How coagulation-inflammatory circuits can be specifically targeted to achieve beneficial macrophage reprogramming after myocardial infarction (MI) is not completely understood. METHODS Mice with permanent ligation of the left anterior descending artery were used to model nonreperfused MI and analyzed by single-cell RNA sequencing, protein expression changes, confocal microscopy, and longitudinal monitoring of recovery. We probed the role of the tissue factor (TF)-FVIIa (activated factor VII)-integrin ß1-PAR2 (protease-activated receptor 2) signaling complex by utilizing genetic mouse models and pharmacological intervention. RESULTS Cleavage-insensitive PAR2R38E and myeloid cell integrin ß1-deficient mice had improved cardiac function after MI compared with controls. Proximity ligation assays of monocytic cells demonstrated that colocalization of FVIIa with integrin ß1 was diminished in monocyte/macrophage FVII-deficient mice after MI. Compared with controls, F7fl/fl CX3CR1 (CX3C motif chemokine receptor 1)Cre mice showed reduced TGF-ß1 and MAP kinase activation, as well as cardiac dysfunction after MI, despite unaltered overall recruitment of myeloid cells. Single-cell mRNA sequencing of CD45 (cluster of differentiation 45)+ cells 3 and 7 days after MI uncovered a trajectory from recruited monocytes to inflammatory TF+/TREM (triggered receptor expressed on myeloid cells) 1+ macrophages requiring F7. As early as 7 days after MI, macrophage F7 deletion led to an expansion of reparative Olfml 3 (olfactomedin-like protein 3)+ macrophages and, conversely, to a reduction of TF+/TREM1+ macrophages, which were also reduced in PAR2R38E mice. Short-term treatment from days 1 to 5 after nonreperfused MI with a monoclonal antibody inhibiting the macrophage TF-FVIIa-PAR2 signaling complex without anticoagulant activity improved cardiac dysfunction, decreased excess fibrosis, attenuated vascular endothelial dysfunction, and increased survival 28 days after MI. CONCLUSIONS Extravascular TF-FVIIa-PAR2 complex signaling drives inflammatory macrophage polarization in ischemic heart disease. Targeting this signaling complex for specific therapeutic macrophage reprogramming following MI attenuates cardiac fibrosis and improves cardiovascular function.

中文翻译：

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巨噬细胞表达的凝血因子 VII 促进不良心脏重塑。


背景 过度的纤维化重塑会导致缺血性心脏病中的心功能障碍，这是由骨髓细胞的凝血信号传导引起的 MAP（丝裂原激活蛋白）激酶依赖性 TGF-β1（转化生长因子-β1）激活所驱动的。心肌梗塞 (MI) 后如何专门针对凝血-炎症回路以实现有益的巨噬细胞重编程尚不完全清楚。方法 使用永久结扎左前降支动脉的小鼠来模拟非再灌注心肌梗死，并通过单细胞 RNA 测序、蛋白质表达变化、共聚焦显微镜和恢复的纵向监测进行分析。我们利用遗传小鼠模型和药理干预探讨了组织因子 (TF)-FVIIa（激活因子 VII）-整合素 ß1-PAR2（蛋白酶激活受体 2）信号复合物的作用。结果 与对照组相比，切割不敏感的 PAR2R38E 和骨髓细胞整合素 ß1 缺陷小鼠在 MI 后心脏功能得到改善。单核细胞的邻近连接测定表明，MI 后单核细胞/巨噬细胞 FVII 缺陷小鼠中 FVIIa 与整合素 ß1 的共定位减少。与对照组相比，F7fl/fl CX3CR1（CX3C 基序趋化因子受体 1）Cre 小鼠表现出 TGF-β1 和 MAP 激酶激活减少，以及 MI 后的心脏功能障碍，尽管骨髓细胞的总体募集没有改变。 MI 后 3 天和 7 天的 CD45（分化簇 45）+ 细胞的单细胞 mRNA 测序揭示了从募集的单核细胞到需要 F7 的炎症 TF+/TREM（骨髓细胞上表达的触发受体）1+ 巨噬细胞的轨迹。 早在 MI 后 7 天，巨噬细胞 F7 缺失就导致修复性 Olfml 3（嗅觉素样蛋白 3）+ 巨噬细胞扩增，相反，导致 TF+/TREM1+ 巨噬细胞减少，在 PAR2R38E 小鼠中，TF+/TREM1+ 巨噬细胞也减少。在未再灌注 MI 后第 1 至 5 天，使用抑制巨噬细胞 TF-FVIIa-PAR2 信号复合物的单克隆抗体（不含抗凝活性）进行短期治疗，可改善心脏功能障碍，减少过度纤维化，减轻血管内皮功能障碍，并提高 MI 后 28 天的生存率。结论 血管外 TF-FVIIa-PAR2 复合物信号传导驱动缺血性心脏病中的炎症巨噬细胞极化。心肌梗死后，针对这种信号复合物进行特异性治疗性巨噬细胞重编程，可减轻心脏纤维化并改善心血管功能。