Parthenogenetic Activation (PA)
Parthenogenetic activation (PA), also known as Parthenogenesis, is an asexual reproduction that activates an oocyte to escape the metaphase II arrest so that it can develop to the next stage. This is a way of generating offspring solely from unfertilized oocytes using chemical agents mimicking the calcium oscillation induced by sperm; thus is a relatively simple way to assess the developmental competence of an embryo in vitro...Read More
In mammals, fertilization begins when the sperm successfully meet the oocyte, and it naturally occurs in vivo in the female reproductive tract. In vitro fertilization (IVF) is a process of modifying the environment so that sperm and oocytes can fertilize and subsequently develop outside their physiologic environment. Culture media and environmental manipulation are thus essential to maintain the gamet quality and developmental competency during the process...Read More
Intracytoplasmic Sperm Injection (ICSI)
Normal fertilization requires both healthy oocytes and sperm with their respective indicators. Healthy oocytes show normal cytoplasmic morphology, sufficient distribution and potential of mitochondria, low reactive oxygen species, unreleased cortical granules, and a barrel-shaped spindle. On the other side, healthy sperm must have normal morphology from head to tail, intact acrosome and DNA, sufficient number within an ejaculate, and high motility, either progressive or hyperactive. If some of those cases are not fulfilled, i.e., lacking sperm number/concentration and aged oocytes, normal fertilization would not likely occur. At this point, ICSI comes to the aid...Read More
Metaphase-II Spindle Injection (MESI)
Due to the relevance of aging in infertility, methods to rejuvenate and improve oocyte quality have been developed. One of which is through Mitochondrial replacement therapies (MRTs). MESI is one of the heterologous total cytoplasmic transfer within MRTs, where the spindle and its chromosome (karyoplast) are transferred from a patient's oocyte (possessing poor mitochondrial quality) to the donor enucleated oocytes...Read More
Orthotopic Ovarian Tissue Transplantation (OTT)
Ovarian transplantation is one of the ways to conserve fertility in mammals. In humans, ovarian transplantation has been applied at the medical center for those undergoing cancer therapies, which are known as gonadotoxic treatments. This procedure is usually initiated with the cryopreservation of ovarian tissue and grafting back at its original location through surgery. Beyond this application, this procedure offers wide implementation to other mammals, especially in an effort to conserve the endangered wildlife species. In animal models like mice, numerous studies have been attempted with varying rates of success...Read More
Embryo transfer (ET) is a key procedure related to assisted reproductive technologies (ART) in mice. The success of other gamete manipulation in vitro techniques and their efficiency need to be confirmed with their in vivo developmental competency, evidenced by the ability to produce a successful pregnancy after embryo transfer. Depending on the ARTs used, the number of embryos transferred into the oviduct between 8–12 is generally used in IVF and ICSI seems to produce a higher success rate measured as the ratio between the number of embryos transferred and the number of pups born. However, a higher number is required for advanced engineering such as SCNT, which usually has a lower pups rate...Read More
