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Updated: Jun 20, 2026
12:11
Analysis of Chromosome Segregation, Histone Acetylation, and Spindle Morphology in Horse Oocytes
Published on: May 11, 2017
Parthenogenesis and somatic cell nuclear transfer in sheep oocytes using Polscope.
Pandit Nandedkar1, Parul Chohan, Archana Patwardhan
1Stem Cell Biology Department, National Institute for Research in Reproductive Health, Parel, Mumbai 400 012, India.
Indian Journal of Experimental Biology
|September 19, 2009
Summary
Parthenogenesis and Somatic cell nuclear transfer (SCNT) in sheep oocytes were explored to refine techniques for human applications. While parthenogenetic activation yielded blastocysts, SCNT produced only morulae, indicating a need for further optimization for generating stem cells.
Area of Science:
- Reproductive biology
- Stem cell science
- Developmental biology
Background:
- Manipulating human embryonic stem cells (hESCs) is crucial for disease modeling, drug discovery, and personalized therapies.
- Parthenogenesis and Somatic Cell Nuclear Transfer (SCNT) are key techniques for genetic manipulation of hESCs.
- Human oocytes are precious, necessitating preliminary studies in a more accessible model system.
Purpose of the Study:
- To develop and optimize methods for embryo reconstruction using sheep oocytes as a model.
- To establish expertise in parthenogenesis and SCNT prior to application in human SCNT.
- To assess the feasibility of generating blastocysts and potentially autologous stem cells.
Main Methods:
- In vitro maturation of sheep oocytes for 20-24 hours to obtain metaphase II (MII) stage.
- Parthenogenetic activation of MII oocytes using calcium ionomycin or ethanol.
- Somatic Cell Nuclear Transfer (SCNT) using cumulus cells as donor nuclei into enucleated MII oocytes.
Main Results:
- In vitro maturation yielded 65% MII oocytes.
- Parthenogenetic activation of 350 oocytes resulted in 16 blastocysts.
- SCNT using 139 oocytes resulted in reconstructed embryos that only reached the morula stage.
Conclusions:
- Parthenogenesis is a viable method for producing blastocysts in sheep oocytes.
- SCNT in sheep oocytes using cumulus cells requires further refinement to achieve blastocyst development.
- The established procedures provide a foundation for future studies involving human oocytes for autologous stem cell generation.
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