Ministrini Stefano, Liberale Luca, Puspitasari Yustina M, Han Jiaying, Kirmes Kilian, Unkelbach Leonhard Paul, Tirandi Amedeo, Niederberger Rebecca, Bengs Susan, Beer Jürg H, Montecucco Fabrizio, Libby Peter, Lüscher Thomas F, Bongiovanni Dario, Camici Giovanni G
Center for Molecular Cardiology, University of Zurich, Schlieren, Switzerland (S.M., Y.M.P., A.T., R.N., S.B., J.H.B., T.F.L., G.G.C.).
First Clinic of Internal Medicine, Department of Internal Medicine, University of Genoa, Italy (L.L., A.T., F.M.).
Arterioscler Thromb Vasc Biol. 2025 Aug;45(8):1432-1439. doi: 10.1161/ATVBAHA.125.322533. Epub 2025 Jun 19.
Recent clinical trials demonstrated a reduction in biomarkers of thrombosis and inflammation in patients with very high cardiovascular risk treated with the anti-IL-6 (interleukin 6) monoclonal antibody ziltivekimab. However, if and how direct IL-6 inhibition exerts antithrombotic effects remains unknown. This translational project aimed to investigate the effect of direct IL-6 inhibition on experimental arterial thrombus formation and its underlying cellular mechanisms.
Three-month-old C57BL/6J male and female mice received very low dose lipopolysaccharide for 4 weeks; in addition to lipopolysaccharide, during the fourth week, mice were randomized to receive either anti-mouse IL-6 monoclonal antibody 200 μg or IgG1 isotype control. Thrombosis of the right common carotid artery was induced by endothelial-targeted laser injury. Coagulation factors and platelet reactivity were assessed in treated mice and controls. Platelets were isolated from whole blood and their reactivity to different chemical stimuli was measured by fluorescence-activated cell sorting. Additionally, whole blood samples from patients with a history of percutaneous coronary intervention were incubated ex vivo with either ziltivekimab biosimilar or IgG1 isotype control. Platelet reactivity at rest and in response to diverse chemical stimuli was quantified by fluorescence-activated cell sorting.
Mice with low-grade chronic inflammation treated with anti-IL-6 monoclonal antibody displayed significantly blunted thrombus formation, without any significant difference in coagulation factors. Ex vivo stimulation with Collagen-rP (collagen-related peptide) significantly activated platelets isolated from control mice but not those obtained from mice treated with anti-IL-6 monoclonal antibody. Similarly, platelet reactivity from patients with previous percutaneous coronary intervention fell significantly after ex vivo treatment with ziltivekimab biosimilar.
Direct IL-6 inhibition blunts thrombus formation by reducing collagen-induced platelet activation. These findings offer a potential mechanistic explanation for the results observed in the RESCUE trial and support the rationale of the ongoing ZEUS trial (Ziltivekimab Cardiovascular Outcome Study).
近期临床试验表明，使用抗白细胞介素6（IL-6）单克隆抗体泽替吉单抗治疗的心血管风险极高的患者，其血栓形成和炎症生物标志物有所减少。然而，直接抑制IL-6是否以及如何发挥抗血栓作用仍不清楚。本转化研究项目旨在探讨直接抑制IL-6对实验性动脉血栓形成及其潜在细胞机制的影响。
3月龄C57BL/6J雄性和雌性小鼠接受极低剂量脂多糖处理4周；除脂多糖外，在第4周，小鼠被随机分为接受200μg抗小鼠IL-6单克隆抗体或IgG1同型对照。通过内皮靶向激光损伤诱导右颈总动脉血栓形成。评估治疗小鼠和对照小鼠的凝血因子和血小板反应性。从全血中分离血小板，并通过荧光激活细胞分选测量其对不同化学刺激的反应性。此外，将有经皮冠状动脉介入治疗史患者的全血样本与泽替吉单抗生物类似物或IgG1同型对照进行体外孵育。通过荧光激活细胞分选对静息和对不同化学刺激反应时的血小板反应性进行定量。
用抗IL-6单克隆抗体治疗的轻度慢性炎症小鼠血栓形成明显减弱，凝血因子无显著差异。用胶原相关肽（Collagen-rP）进行体外刺激可显著激活从对照小鼠分离的血小板，但不能激活从用抗IL-6单克隆抗体治疗的小鼠获得的血小板。同样，在用泽替吉单抗生物类似物进行体外治疗后，既往有经皮冠状动脉介入治疗史患者的血小板反应性显著下降。
直接抑制IL-6可通过减少胶原诱导的血小板活化来减弱血栓形成。这些发现为RESCUE试验中观察到的结果提供了潜在的机制解释，并支持正在进行的ZEUS试验（泽替吉单抗心血管结局研究）的理论依据。
