- 著者
- Hiroshi Fujii Yu Ikeuchi Yasutaka Kurata Nobuhito Ikeda Udin Bahrudin Peili Li Yuji Nakayama Ryo Endo Akira Hasegawa Kumi Morikawa Junichiro Miake Akio Yoshida Kyoko Hidaka Takayuki Morisaki Haruaki Ninomiya Yasuaki Shirayoshi Kazuhiro Yamamoto Ichiro Hisatome
- 出版者
- 日本循環器学会
- 雑誌
- Circulation Journal (ISSN:13469843)
- 巻号頁・発行日
- pp.CJ-12-0126, (Released:2012-09-04)
- 参考文献数
- 27
- 被引用文献数
- 3 2
Background: The prion protein (PrP) has been reported to serve as a surface maker for isolation of cardiomyogenic progenitors from murine embryonic stem (ES) cells. Although PrP-positive cells exhibited automaticity, their electrophysiological characteristics remain unresolved. The aim of the present study was therefore to investigate the electrophysiological properties of PrP-positive cells in comparison with those of HCN4p-or Nkx2.5-positive cells. Methods and Results: Differentiation of AB1, HCN5p-EGFP and hcgp7 ES cells into cardiac progenitors was induced by embryoid body (EB) formation. EBs were dissociated and cells expressing PrP, HCN4-EGFP and/or Nkx2.5-GFP were collected via flow cytometry. Sorted cells were subjected to reverse transcriptase-polymerase chain reaction, immunostaining and patch-clamp experiments. PrP-positive cells expressed mRNA of undifferentiation markers, first and second heart field markers, and cardiac-specific genes and ion channels, indicating their commitment to cardiomyogenic progenitors. PrP-positive cells with automaticity showed positive and negative chronotropic responses to isoproterenol and carbamylcholine, respectively. Hyperpolarization-activated cation current (If) was barely detectable, whereas Na+ and L-type Ca2+ channel currents were frequently observed. Their spontaneous activity was slowed by inhibition of sarcoplasmic reticulum Ca2+ uptake and release but not by blocking If. The maximum diastolic potential of their spontaneous firings was more depolarized than that of Nkx2.5-GFP-positive cells. Conclusions: PrP-positive cells contained cardiac progenitors that separated from the lineage of sinoatrial node cells. PrP can be used as a marker to enrich nascent cardiac progenitors.