Asimaki Angeliki, Protonotarios Alexandros, James Cynthia A, Chelko Stephen P, Tichnell Crystal, Murray Brittney, Tsatsopoulou Adalena, Anastasakis Aris, te Riele Anneline, Kléber André G, Judge Daniel P, Calkins Hugh, Saffitz Jeffrey E
From the Department of Pathology, Beth Israel Deaconess Medical Center & Harvard Medical School, Boston, MA (A. Asimaki, A.G.K., J.E.S.); Nikos Protonotarios Medical Center, Naxos, Greece (A.P., A.T.); Department of Medicine/Cardiology, Johns Hopkins University School of Medicine, Baltimore, MD (C.A.J., S.P.C., C.T., B.M., A.t.R., D.P.J., H.C.); and First Department of Cardiology, University of Athens Medical School, Athens, Greece (A. Anastasakis).
Circ Arrhythm Electrophysiol. 2016 Feb;9(2):e003688. doi: 10.1161/CIRCEP.115.003688.
Analysis of myocardium has revealed mechanistic insights into arrhythmogenic cardiomyopathy but cardiac samples are difficult to obtain from probands and especially from family members. To identify a potential surrogate tissue, we characterized buccal mucosa cells.
Buccal cells from patients, mutation carriers, and controls were immunostained and analyzed in a blinded fashion. In additional studies, buccal cells were grown in vitro and incubated with SB216763. Immunoreactive signals for the desmosomal protein plakoglobin and the major cardiac gap junction protein Cx43 were markedly diminished in buccal mucosa cells from arrhythmogenic cardiomyopathy patients with known desmosomal mutations when compared with controls. Plakoglobin and Cx43 signals were also reduced in most family members who carried disease alleles but showed no evidence of heart disease. Signal for the desmosomal protein plakophilin-1 was reduced in buccal mucosa cells in patients with PKP2 mutations but not in those with mutations in other desmosomal genes. Signal for the desmosomal protein desmoplakin was reduced in buccal mucosa cells from patients with mutations in DSP, DSG2, or DSC2 but not in PKP2 or JUP. Abnormal protein distributions were reversed in cultured cells incubated with SB216763, a small molecule that rescues the disease phenotype in cardiac myocytes.
Buccal mucosa cells from arrhythmogenic cardiomyopathy patients exhibit changes in the distribution of cell junction proteins similar to those seen in the heart. These cells may prove useful in future studies of disease mechanisms and drug screens for effective therapies in arrhythmogenic cardiomyopathy.
对心肌的分析揭示了致心律失常性心肌病的发病机制，但心脏样本很难从先证者尤其是家庭成员中获取。为了确定一种潜在的替代组织，我们对颊黏膜细胞进行了特征分析。
对患者、突变携带者和对照者的颊细胞进行免疫染色，并以盲法进行分析。在其他研究中，颊细胞在体外培养并与SB216763孵育。与对照组相比，已知桥粒突变的致心律失常性心肌病患者的颊黏膜细胞中，桥粒蛋白盘状球蛋白和主要心脏间隙连接蛋白Cx43的免疫反应信号明显减弱。在大多数携带疾病等位基因但无心脏病证据的家庭成员中，盘状球蛋白和Cx43信号也降低。PKP2突变患者的颊黏膜细胞中桥粒蛋白桥粒芯蛋白-1的信号降低，但其他桥粒基因突变患者的颊黏膜细胞中未降低。DSP、DSG2或DSC2突变患者的颊黏膜细胞中桥粒蛋白桥粒斑蛋白的信号降低，但PKP2或JUP突变患者的颊黏膜细胞中未降低。在用SB216763（一种能挽救心肌细胞疾病表型的小分子）孵育的培养细胞中，异常的蛋白质分布得到逆转。
致心律失常性心肌病患者的颊黏膜细胞表现出细胞连接蛋白分布的变化，类似于心脏中的变化。这些细胞可能在未来疾病机制研究和致心律失常性心肌病有效治疗药物筛选中发挥作用。
