Received July 20, 2022
Accepted December 02, 2022

Objective:The presence of immature or fail to fertilize oocytes is not uncommon in Assisted Reproduction (AR) cycles and they are usually discarded. These oocytes may still respond to an external stimulus to generate embryos with limited developmental capacity, but capable to give rise to human embryonic stem cell (hESC) lines. This strategy overcomes ethical problems involved in the use of human embryos generated for reproductive reasons to create hESClines. Methods:In the present study discarded human oocytes and bovine oocytes obtained from an abattoir and matured in vitro were parthenogenetically activated using SrCl2 or Ca2+ ionophore. Results:Human oocytes cultured for 4 or 22hrs in presence of SrCl2 showed 9,7 and 8,3% of activation and 6,4 and 8,3% of embryonic development, respectively. The exposure of 7 oocytes to medium containing Ca2+ ionophore resulted in 2 activated and cleaved parthenotes. In bovines, activation and embryonic development after exposure to Sr2+ were 2.6 and 26.3%, respectively. Using the ionophore, activation and embryo development rates were 47 and 69%, respectively. Among the cleaved embryos, 23% of them reached the blastocyst stage after exposure to the ionophore followed by 3.5hrs in 6-DMAP. These results suggest us that Ca2+ ionophore together with 6-DMAP represents a better activating agent to induce embryo development in human and bovine oocytes. Conclusion: This system will be used now on to activate human and bovine oocytes aiming to establish a protocol for the creation of hESC colonies with clinical pre-GMP (good manufacturing practice) grade for future use in regenerative medicine.