Long-Term Effect of a Vaccine Targeting Endothelin-1 Receptor Type A in Pulmonary Arterial Hypertension
Yong Dai, Zhihua Qiu, Wenrui Ma, Chang Li, Xiao Chen, Xiaoxiao Song, Zeyang Bai, Dingyang Shi, Jiayu Zheng, Guangwei Pan, Yuhua Liao, Mengyang Liao, Zihua Zhou
Abstract
Background: Previously, we invented a therapeutic vaccine targeting the endothelin-A receptor (termed ETRQβ-002). ETRQβ-002 successfully prevented the remodeling of pulmonary arterioles (PAs) and right ventricle (RV) without significant immune-mediated damage in experimental pulmonary arterial hypertension (PAH) mice models. Objective: Here, we aim to further evaluate the long-term effects of ETRQβ-002. Methods: PAH mice model was induced by a combination of subcutaneous injection with Sugen5416 and chronic hypoxic conditions (10% O 2 ). PAH mice were immunized with ETRQβ-002 at different time points, and the experiment lasted for 21 weeks. Hemodynamic, histological, and biochemical analyses were conducted to evaluate the long-term effects of ETRQβ-002. Results: We demonstrated that the titer of the specific antibody against ETR-002 could be maintained chronically after periodic booster immunization in PAH mice. Long-term reduction of right ventricular systolic pressure and amelioration of PA remodeling by ETRQβ-002 were confirmed. Moreover, we found that ETRQβ-002 also exerted antiproliferation, anti-inflammation, and antifibrosis effects in PA remodeling. Besides, ETRQβ-002 durably limited pathological RV hypertrophy and fibrosis. Finally, no immune-mediated damage was observed in hepatic or renal function or by pathology in liver and kidney during the long-term administration of ETRQβ-002. Conclusion: Our findings indicate that ETRQβ-002 provides long-term therapeutic effects in Sugen/hypoxia-induced PAH animals and offers a promising clinical prospect for PAH treatment.