Ultrastructure of human embryonic stem cells and spontaneous and retinoic acid-induced differentiating cells.
Ultrastructural and immunohistochemical studies of 4 groups of cells-(human embryonic stem cells (hES), embryoid bodies (EB), and spontaneously and retinoic acid (RA)-induced differentiating cells)-were carried out to investigate their detailed phenotype. Immunohistochemically, the EB cells showed strong immunoreactivity for CD34, CD117, and nestin. Differentiating cells expressed pancytokertin, vimentin, CD31, CD56, GFAP, nestin, and NeuN as well as CD34, and c-Kit. However, synaptophysin and neurofilaments were not present in these same differentiating cells. Transmission electron microscopy showed that hES and EB cells were very similar to germ cells or cells of the inner cell mass. Spontaneously and RA-induced differentiating cells exhibited epithelial, mesenchymal, endodermal, and neuronal phenotypes. The perikarya of the neuronal cells had rich RERs (Nissl substance) and long cytoplasmic processes filled with numerous neural tubules. However, neither synaptic junctions nor synaptic vesicles were developed. In our study, RA treatment with brain-derived growth factor and TGFalpha in neuron differentiation medium induced not only neuronal differentiation but also pluripotential differentiation. Full neuronal differentiation did not occur after 2 weeks in culture, as no synaptic junctions and synaptic vesicles developed.
Park
Sung-Hye
SH
Department of Pathology, Seoul National University, College of Medicine, Seoul, South Korea. shparknp@plaza.snu.ac.kr
Park
Seong Hoe
SH
Kook
Myeong-Cherl
MC
Kim
Eun-Young
EY
Park
Sepill
S
Lim
Jin Ho
JH
D000970:Antineoplastic Agents / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D004622:Embryo, Mammalian; D006133:Growth Substances / Q000494:pharmacology; D006801:Humans; D007150:Immunohistochemistry; D046529:Microscopy, Electron, Transmission; D039902:Multipotent Stem Cells / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure*; D009474:Neurons / Q000166:cytology; D014212:Tretinoin / Q000494:pharmacology*
D000970:Antineoplastic Agents; D006133:Growth Substances; D014212:Tretinoin