Cardiomyocytes fuse with surrounding noncardiomyocytes and reenter the cell cycle.
The concept of the plasticity or transdifferentiation of adult stem cells has been challenged by the phenomenon of cell fusion. In this work, we examined whether neonatal cardiomyocytes fuse with various somatic cells including endothelial cells, cardiac fibroblasts, bone marrow cells, and endothelial progenitor cells spontaneously in vitro. When cardiomyocytes were cocultured with endothelial cells or cardiac fibroblasts, they fused and showed phenotypes of cardiomyocytes. Furthermore, cardiomyocytes reentered the G2-M phase in the cell cycle after fusing with proliferative noncardiomyocytes. Transplanted endothelial cells or skeletal muscle-derived cells fused with adult cardiomyocytes in vivo. In the cryoinjured heart, there were Ki67-positive cells that expressed both cardiac and endothelial lineage marker proteins. These results suggest that cardiomyocytes fuse with other cells and enter the cell cycle by maintaining their phenotypes.
Matsuura
Katsuhisa
K
Department of Cardiovascular Science and Medicine, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan.
Wada
Hiroshi
H
Nagai
Toshio
T
Iijima
Yoshihiro
Y
Minamino
Tohru
T
Sano
Masanori
M
Akazawa
Hiroshi
H
Molkentin
Jeffery D
JD
Kasanuki
Hiroshi
H
Komuro
Issei
I
D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D030801:Animals, Genetically Modified; D002450:Cell Communication; D002453:Cell Cycle; D002454:Cell Differentiation; D002455:Cell Division; D019070:Cell Lineage; D049109:Cell Proliferation; D017690:Cell Transplantation; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism; D016195:G2 Phase; D049452:Green Fluorescent Proteins / Q000378:metabolism; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000096:biosynthesis; D007763:Lac Operon; D008297:Male; D051379:Mice; D008957:Models, Genetic; D018482:Muscle, Skeletal / Q000166:cytology; D032383:Myocytes, Cardiac / Q000378:metabolism*; D015739:Nocodazole / Q000494:pharmacology; D010641:Phenotype; D051381:Rats; D017208:Rats, Wistar; D011995:Recombination, Genetic; D013997:Time Factors; D019076:Transgenes
D019394:Ki-67 Antigen; D049452:Green Fluorescent Proteins; D015739:Nocodazole