Cardiovascular Medicine, Department of Medicine, Karolinska Institute, Stockholm, Sweden; Vascular Surgery, Department of Molecular Medicine and Surgery, Karolinska Institute and Karolinska University Hospital, Stockholm, Sweden; Department of Pathology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre, The Netherlands.
Division of BioTherapeutics, Leiden Academic Centre for Drug Research, Leiden University, The Netherlands.
Vascul Pharmacol. 2023 Jun;150:107167. doi: 10.1016/j.vph.2023.107167. Epub 2023 Mar 21.
Calcification, a key feature of advanced human atherosclerosis, is positively associated with vascular disease burden and adverse events. We showed that macrocalcification can be a stabilizing factor for carotid plaque molecular biology, due to inverse association with immune processes. Mast cells (MCs) are important contributors to plaque instability, but their relationship with macrocalcification is unexplored. With a hypothesis that MC activation negatively associates with carotid plaque macrocalcification, we aimed to investigate the link between MCs and carotid plaque vulnerability, and study MC role in plaque calcification via smooth muscle cells (SMCs).
Pre-operative computed tomography angiographies of patients (n = 40) undergoing surgery for carotid stenosis were used to characterize plaque morphology. Plaque microarrays (n = 40 and n = 126) were used for bioinformatic deconvolution of immune cell populations. Tissue microarrays (n = 103) were used to histologically validate the contribution of activated and resting MCs in plaques.
Activated MCs and their typical markers were negatively correlated with macrocalcification. The ratio of activated vs. resting MCs was increased in low-calcified plaques from symptomatic patients. There was no modulating effect of medication on MC ratios. In vitro experiments showed that SMC calcification attenuated MC activation, while both active and resting MCs stimulated SMC calcification and induced dedifferentiation towards a pro-inflammatory-, osteochondrocyte-like phenotype, without modulating their migro-proliferative function.
Integrative analyses from human plaques showed that MC activation is inversely associated with macrocalcification and positively with parameters of plaque vulnerability. Mechanistically, MCs induce SMC osteogenic reprograming, while matrix calcification in turn attenuates MC activation, offering new therapeutic avenues for exploration.
钙化是人类动脉粥样硬化晚期的一个关键特征，与血管疾病负担和不良事件呈正相关。我们发现，由于与免疫过程呈负相关，大钙化可能是颈动脉斑块分子生物学的稳定因素。肥大细胞（MCs）是斑块不稳定的重要贡献者，但它们与大钙化的关系尚未得到探索。我们假设 MC 激活与颈动脉斑块大钙化呈负相关，旨在研究 MC 与颈动脉斑块易损性之间的联系，并通过平滑肌细胞（SMCs）研究 MC 在斑块钙化中的作用。
利用接受颈动脉狭窄手术患者的术前计算机断层血管造影术（n=40）来描述斑块形态。使用斑块微阵列（n=40 和 n=126）对免疫细胞群体进行生物信息学去卷积。使用组织微阵列（n=103）对斑块中激活和静止 MCs 的贡献进行组织学验证。
激活的 MCs 及其典型标志物与大钙化呈负相关。来自有症状患者的低钙化斑块中激活的 MC 与静止的 MC 比值增加。药物治疗没有调节 MC 比值的作用。体外实验表明，SMC 钙化减弱了 MC 的激活，而活性和静止的 MCs 均刺激 SMC 钙化，并诱导向促炎、成骨软骨细胞样表型的去分化，而不调节其迁移增殖功能。
来自人类斑块的综合分析表明，MC 激活与大钙化呈负相关，与斑块易损性的参数呈正相关。从机制上讲，MC 诱导 SMC 成骨重编程，而基质钙化反过来又减弱了 MC 的激活，为探索新的治疗途径提供了机会。
