Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA, United States of America; Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, United States of America.
Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA, United States of America; Department of Biological Sciences, Tennessee State University, Nashville, TN, United States of America.
J Mol Cell Cardiol. 2023 Mar;176:98-109. doi: 10.1016/j.yjmcc.2023.02.001. Epub 2023 Feb 9.
The innate immune response contributes to cardiac injury in myocardial ischemia/reperfusion (MI/R). Neutrophils are an important early part of the innate immune response to MI/R. Adenosine, an endogenous purine, is a known innate immune modulator and inhibitor of neutrophil activation. However, its delivery to the heart is limited by its short half-life (<30 s) and off-target side effects. CD39 and CD73 are anti-inflammatory homeostatic enzymes that can generate adenosine from phosphorylated adenosine substrate such as ATP released from injured tissue.
We hypothesize that hydrogel-delivered CD39 and CD73 target the local early innate immune response, reduce neutrophil activation, and preserve cardiac function in MI/R injury.
We engineered a poly(ethylene) glycol (PEG) hydrogel loaded with the adenosine-generating enzymes CD39 and CD73. We incubated the hydrogels with neutrophils in vitro and showed a reduction in hydrogen peroxide production using Amplex Red. We demonstrated availability of substrate for the enzymes in the myocardium in MI/R by LC/MS, and tested release kinetics from the hydrogel. On echocardiography, global longitudinal strain (GLS) was preserved in MI/R hearts treated with the loaded hydrogel. Delivery of purinergic enzymes via this synthetic hydrogel resulted in lower innate immune infiltration into the myocardium post-MI/R, decreased markers of macrophage and neutrophil activation (NETosis), and decreased leukocyte-platelet complexes in circulation.
In a rat model of MI/R injury, CD39 and CD73 delivered via a hydrogel preserve cardiac function by modulating the innate immune response.
先天免疫反应有助于心肌缺血/再灌注（MI/R）引起的心脏损伤。中性粒细胞是 MI/R 先天免疫反应的重要早期组成部分。腺苷是一种内源性嘌呤，是已知的先天免疫调节剂和中性粒细胞激活抑制剂。然而，其向心脏的输送受到半衰期（<30 秒）和非靶向副作用的限制。CD39 和 CD73 是抗炎稳态酶，可从损伤组织释放的磷酸化腺苷底物（如 ATP）生成腺苷。
我们假设水凝胶递送的 CD39 和 CD73 靶向局部早期先天免疫反应，减少中性粒细胞激活，并在 MI/R 损伤中保护心脏功能。
我们设计了一种负载腺苷生成酶 CD39 和 CD73 的聚乙二醇（PEG）水凝胶。我们在体外将水凝胶与中性粒细胞孵育，并使用 Amplex Red 显示过氧化氢生成减少。我们通过 LC/MS 证明了 MI/R 心肌中酶的底物可用性，并测试了水凝胶的释放动力学。在超声心动图上，用负载水凝胶治疗的 MI/R 心脏的整体纵向应变（GLS）得到保留。通过这种合成水凝胶递送电苷酶会导致 MI/R 后心肌中先天免疫浸润减少，巨噬细胞和中性粒细胞激活标志物（NETosis）减少，循环中白细胞-血小板复合物减少。
在 MI/R 损伤的大鼠模型中，通过水凝胶递送的 CD39 和 CD73 通过调节先天免疫反应来保护心脏功能。
