“…Based on the results, the treatment of iDPSCs with 20% HPL could significantly increase the cell viability of the expression of angiogenic genes (ANGPT1, EREG, FGF2, FIGF, VEGF-A, IGF-1, JAG1, NPR2, PLDXC1, and STAB1), adhesion molecules, cytokine-producing genes, and growth factors (FGF-2, MCP-1, PDGF-BB, HGF, and VEGF-A) [43]. In the current study, the cryopreservation of preantral follicles was accomplished using a cryotop device, which was successfully applied for oocyte [44,45], embryos [45,46] and follicles [47] vitrification. In addition, the cryopreservation process could be affected by the type of cryo-device, which enables loading of the least amount of fluid, and accelerates temperature drop throughout the vitrification process [48].…”
Background: Transplantation of cryopreserved follicles can be regarded as a promising strategy for preserving fertility in cancer patients under chemotherapy and radiotherapy by reducing the risk of cancer recurrence. The present study aimed to evaluate whether fibrin hydrogel supplemented with platelet lysate (PL) could be applied to enhance follicular survival, growth, and angiogenesis in cryopreserved preantral follicle grafts. Materials and Methods: Preantral follicles were extracted from 15 four-week-old NMRI mice, cryopreserved by cryotop method, and encapsulated in fibrin-platelet lysate for subsequent heterotopic (subcutaneous) auto-transplantation into the neck. Transplants were assessed in three groups including fresh follicles in fibrin-15%PL, cryopreserved follicles in fibrin-15%PL, and cryopreserved follicles in fibrin-0% PL. Two weeks after transplantation, histological, and immunohistochemistry (CD31) analysis were applied to evaluate follicle morphology, survival rate, and vascular formation, respectively. Results: Based on the results, fibrin-15% PL significantly increased neovascularization and survival rate (SR) both in cryopreserved (SR=66.96%) and fresh follicle (SR=90.8%) grafts, compared to PL-less fibrin cryopreserved transplants (SR=28.46%). The grafts supplemented with PL included a significantly higher percentage of preantral and antral follicles. Also, no significant difference was observed in the percentage of preantral follicles between cryopreserved and fresh grafts of fibrin-15% PL. However, a significantly lower (P=0.03) percentage of follicles (23.37%) increased to the antral stage in cryopreserved grafts of fibrin-15%PL, compared to fresh grafts (35.01%). Conclusion: The findings demonstrated that fibrin-PL matrix could be a promising strategy to improve cryopreserved follicle transplantation and preserve fertility in cancer patients at the risk of ovarian failure. [GMJ.2020;9:e1558]
“…Based on the results, the treatment of iDPSCs with 20% HPL could significantly increase the cell viability of the expression of angiogenic genes (ANGPT1, EREG, FGF2, FIGF, VEGF-A, IGF-1, JAG1, NPR2, PLDXC1, and STAB1), adhesion molecules, cytokine-producing genes, and growth factors (FGF-2, MCP-1, PDGF-BB, HGF, and VEGF-A) [43]. In the current study, the cryopreservation of preantral follicles was accomplished using a cryotop device, which was successfully applied for oocyte [44,45], embryos [45,46] and follicles [47] vitrification. In addition, the cryopreservation process could be affected by the type of cryo-device, which enables loading of the least amount of fluid, and accelerates temperature drop throughout the vitrification process [48].…”
Background: Transplantation of cryopreserved follicles can be regarded as a promising strategy for preserving fertility in cancer patients under chemotherapy and radiotherapy by reducing the risk of cancer recurrence. The present study aimed to evaluate whether fibrin hydrogel supplemented with platelet lysate (PL) could be applied to enhance follicular survival, growth, and angiogenesis in cryopreserved preantral follicle grafts. Materials and Methods: Preantral follicles were extracted from 15 four-week-old NMRI mice, cryopreserved by cryotop method, and encapsulated in fibrin-platelet lysate for subsequent heterotopic (subcutaneous) auto-transplantation into the neck. Transplants were assessed in three groups including fresh follicles in fibrin-15%PL, cryopreserved follicles in fibrin-15%PL, and cryopreserved follicles in fibrin-0% PL. Two weeks after transplantation, histological, and immunohistochemistry (CD31) analysis were applied to evaluate follicle morphology, survival rate, and vascular formation, respectively. Results: Based on the results, fibrin-15% PL significantly increased neovascularization and survival rate (SR) both in cryopreserved (SR=66.96%) and fresh follicle (SR=90.8%) grafts, compared to PL-less fibrin cryopreserved transplants (SR=28.46%). The grafts supplemented with PL included a significantly higher percentage of preantral and antral follicles. Also, no significant difference was observed in the percentage of preantral follicles between cryopreserved and fresh grafts of fibrin-15% PL. However, a significantly lower (P=0.03) percentage of follicles (23.37%) increased to the antral stage in cryopreserved grafts of fibrin-15%PL, compared to fresh grafts (35.01%). Conclusion: The findings demonstrated that fibrin-PL matrix could be a promising strategy to improve cryopreserved follicle transplantation and preserve fertility in cancer patients at the risk of ovarian failure. [GMJ.2020;9:e1558]
“…However, if we consider that several of the preparation protocols that are used daily in clinical practice resemble the EP described in this work 12,16–18 , it could be argued that current vitrification outcomes support the tolerance of the human M-II oocyte and embryo to the osmotic and mechanical stresses derived from the osmolarity of the nVS and VS employed (2901 and 7060 Osmolal, respectively). For instance, the effect on the meiotic spindle and oocyte competence of similar CPA exposure regimes, which according to the biophysical simulation produces shrinking to 50% of the oocyte’s isotonic volume, has been assessed on human 17 and mice 26 satisfactorily.…”
Section: Discussionmentioning
confidence: 99%
“…Ultimately, the developmental ability of oocytes and embryos is the indicator of the safety and efficiency of a vitrification procedure 46 . Preliminary tests in the murine model would be necessary to confirm the validity of the proposed protocol for human oocyte and embryo cryopreservation 26,44 .Figure 2 In vitro recording of the volumetric excursion of human M-II oocytes subjected to: Dehydration protocol (DP); Equilibration Protocol (EP) of preparation for vitrification. Exposure to nVS starts at t = 0, the change to VS is demarcated at the X-axis.…”
Vitrification of human oocytes and embryos in different stages of development is a key element of daily clinical practice of in vitro fertilization treatments. Despite the cooling and warming of the cells is ultra-fast, the procedure as a whole is time consuming. Most of the duration is employed in a long (8–15 minutes), gradual or direct exposure to a non-vitrifying cryoprotectant solution, which is followed by a short exposure to a more concentrated vitrifying solution. A reduction in the duration of the protocols is desirable to improve the workflow in the IVF setting and reduce the time of exposure to suboptimal temperature and osmolarity, as well as potentially toxic cryoprotectants. In this work it is shown that this reduction is feasible. In silico (MatLab program using two-parameter permeability model) and in vitro observations of the oocytes’ osmotic behaviour indicate that the dehydration upon exposure to standard cryoprotectant solutions occurs very fast: the point of minimum volume of the shrink-swell curve is reached within 60 seconds. At that point, intracellular water ejection is complete, which coupled with the permeation of low molecular weight cryoprotectants results in similar intracellular and extracellular solute concentrations. This shows that prolonging the exposure to the cryoprotectant solutions does not improve the cytosolic glass forming tendency and could be avoided. To test this finding, human oocytes and zygotes that were donated for research were subjected to a shortened, dehydration-based protocol, consisting of two consecutive exposures of one-minute to two standard cryoprotectant solutions, containing ethylene glycol, dimethyl sulfoxide and sucrose. At the end of this two-minute dehydration protocol, the critical intracellular solute concentration necessary for successful vitrification was attained, confirmed by the post-warming survival and ability to resume cytokinesis of the cells. Further studies of the developmental competency of oocytes and embryos would be necessary to determine the suitability of this specific dehydration protocol for clinical practice, but based on our results, short times of exposure to increasingly hypertonic solutions could be a more time-efficient strategy to prepare human oocytes and embryos for vitrification.
“…These factors were taken into consideration in the development and validation of the microSecure-VTF system [51], which has proven to be a user-friendly technique offering high inter-technician repeatability and reliability (100% recovery rates), high survival rates, and high live birth rates with human oocytes and blastocysts [44,52,53]. There are also hybrid vitrification device systems like Rapid-i [54] and the Cryotop SC [55] which ultrarapidly cool the device prior to sealing them into a straw container under LN 2 vapor conditions, placing the container at risk of incomplete seals (i.e., particularly the Cryotop SC and homemade cut straw-double container systems). The latter event could allow LN 2 seepage to occur and problematic warming events to transpire if not accounted for properly [56].…”
Section: Quality Control Considerations In Vitrification Systemsmentioning
The fundamental understanding of cryobiology through experimentation in the 1960s, 1970s, and 1980s has led to the development of today's vitrification technology. Although human embryo and oocyte vitrification was slow to evolve, it has become an invaluable technology in the field of reproductive medicine. The aim of this chapter is to discuss some of the underlying basic principles behind forming a metastable glass phase during rapid cooling in liquid nitrogen (LN 2) and the prevention of recrystallization events upon warming. We then highlight how this understanding has led to its highly effective and reliable usage in clinical IVF. Furthermore, we describe how quality control factors (e.g., ease of use, repeatability, reliability, labeling security, and cryostorage safety) can vary between vitrification device systems, potentially influencing clinical outcomes and creating possible liability issues. An open-minded approach to continued experimentation is a necessity, especially pertaining to oocyte freeze preservation, if we are to optimize the vitrification of reproductive cells and tissue in the future.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
