Vascular Smooth Muscle Cell Derived from IPS Cell of Moyamoya Disease - Comparative Characterization with Endothelial Cell Transcriptome.

Background: Moyamoya disease (MMD) is an occlusive cerebrovascular disease, causing stroke in children and young adults with unknown etiology. The fundamental pathology is fibrocellular intimal thickening of cerebral arteries, in which vascular smooth muscle cells (VSMCs) are observed as one of the major cell types. Although the characteristics of circulating smooth muscle progenitor cells have been previously reported, the VSMCs are poorly characterized in MMD. We aimed to characterize VSMCs in MMD using induced pluripotent stem cell (iPSC)-technology. Methods: We differentiated VSMCs from neural crest stem cells (NCSCs) using peripheral blood mononuclear cell-derived iPSCs and compared biological and transcriptome features under naive culture conditions between three independent healthy control (HC) subjects and three MMD patients. VSMC transcriptome profiles were also compared to those of endothelial cells (ECs) differentiated from the same iPSCs. Results: Homogeneous spindle-shaped cells differentiated from iPSCs exhibited smooth muscle cell marker expressions, including alpha-smooth muscle actin (alpha SMA, 82.3 +/- 6.7% and 81.0 +/- 6.7%); calponin (91.3 +/- 2.1% and 90.9 +/- 1.3%); myosin heavy chain-11 (MYH11, 96.9 +/- 0.7% and 97.1 +/- 0.3%) without significance of differences between the two groups. Real-time PCR showed few PECAM1 and CD34 gene expressions in both groups, indicating features of differentiated VSMCs. There were no significant differences in cellular proliferation (p = 0.45), migration (p = 0.60), and contractile abilities (p = 0.96) between the two groups. Transcriptome analysis demonstrated similar gene expression profiles of VSMCs in HC subjects and MMD patients with six differentially expressed genes (DEGs); while ECs showed a distinct transcriptome profile in MMD patients with 120 DEGs. The Wnt-signaling pathway was a significant pathway in VSMCs. Conclusions: This is the first study that established VSMCs from NCSCs using MMD patient-derived iPSCs and demonstrated similar biological function and transcriptome profile of iPSC-derived VMSCs in MMD patients and HC subjects under naive single culture condition. Comparative transcriptome features between iPSC-derived VSMCs and ECs, displaying distinct transcriptome in the ECs, suggested that pathological traits can be driven by naive ECs predominantly and VSMCs may require specific environmental factors in MMD, which provides novel insight into the pathophysiology of MMD. Our iPSC derived VSMC model can contribute to further investigations of diagnostic and therapeutic target of MMD in addition to the current iPSC derived EC model.