Derivation of a diploid human embryonic stem cell line from a mononuclear zygote.
BACKGROUND
IVF occasionally produces aneuploid zygotes with one or three pronuclei (PN). Routinely, these zygotes are discarded. The aim of this work was to establish human embryonic stem cell (hESC) lines from blastocysts resulting from abnormal fertilization.


METHODS
Abnormally fertilized zygotes were cultured to the blastocyst stage and, following zona pellucida digestion, zona-free blastocysts were placed on a mouse feeder layer. Culture of hESCs was carried out as described earlier.


RESULTS
Six out of the nine developing blastocysts attached to the feeder layer. One hESC line, originating from a mononuclear zygote following ICSI, was successfully derived. This line displayed typical phenotype and embryonic surface markers, and exhibited the potential to develop into all three embryonic germ layers both in vitro (by embryoid body formation) and in vivo (teratoma generation). Genetic examination revealed normal diploid karyotype and heterozygotic appearance for metachromatic leukodystrophy (MLD).


CONCLUSIONS
This method, which requires neither immuno nor mechanical removal of the trophectoderm, may facilitate the derivation of hESC lines in general, and those from abnormal embryos in particular. Furthermore, it is shown that aneuploid zygotes can be used as a source for normal hESC derivation and hold the potential to generate aneuploid hESC lines for research purposes.
Suss-Toby
Edith
E
Department of Obstetrics and Gynecology, Rambam Medical Center, POB 9602, Haifa 31096, Israel.
Gerecht-Nir
S
S
Amit
M
M
Manor
D
D
Itskovitz-Eldor
J
J
D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000648:ultrastructure*; D002478:Cells, Cultured; D004171:Diploidy; D005307:Fertilization in Vitro; D006579:Heterozygote; D006614:Hindlimb; D006801:Humans; D066298:In Vitro Techniques; D007621:Karyotyping; D007966:Leukodystrophy, Metachromatic / Q000235:genetics; D051379:Mice; D019042:Muscle Neoplasms / Q000209:etiology / Q000473:pathology; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000166:cytology* / Q000502:physiology; D013724:Teratoma / Q000209:etiology / Q000473:pathology; D014183:Transplantation, Heterologous; D015053:Zygote / Q000166:cytology* / Q000648:ultrastructure