Ovary tissue engineering : a strategy to preserve fertility in cancer patients
(2024)
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- Authors
- Supervisors
- Andrade Amorim, Christiani
- Abstract
- Restoring fertility in cancer patients, especially those at high risk of ovarian metastasis, poses a significant challenge. Conventional options, such as oocyte or embryo cryopreservation, can be impractical due to the urgency of initiating cancer treatment upon diagnosis. On the other hand, newer approaches, like ovarian tissue cryopreservation and transplantation, face limitations due to the potential reintroduction of malignant cells, especially in cases, such as blood-borne and metastasizing cancers. A potential solution lies in utilizing a tissue-engineered ovary. This strategy involves cryopreserving a portion of the patient's ovary upon cancer diagnosis, which is later thawed post-treatment. The isolated follicles are encapsulated in a 3D matrix before transplantation. The main challenge lies in developing a suitable 3D matrix that closely mimics ovarian tissue and provides optimal support for human preantral follicle development. This PhD thesis addresses this challenge, focusing on synthesizing an appropriate PEGylated fibrin hydrogel as a biocompatible and biodegradable biomaterial. The first phase of the research involved characterizing different molar ratios of PEGylated fibrin using human ovarian stromal cells. PEGylation enhanced scaffold stability, supported cell viability and proliferation, with specific formulations showing notable effects. PEG: Fib 5:1 T50 demonstrated a significantly higher cell density dynamic and a non-significantly lower expression of caspase-3 on day 5, while PEG: Fib 10:1 T50 exhibited uniform cell distribution and a tendency toward a high rate of Ki67-positive cells. Building upon these promising findings, the second phase of the study aimed to tailor a PEGylated fibrin hydrogel formulation with mechanical strength similar to the human ovarian cortex at reproductive age. The tailored hydrogel was then tested to encapsulate and in vitro culture isolated human preantral follicles. Design-Expert® software was employed to achieve a biomechanically tailored PEGylated fibrin formulation with specific mechanical properties mimicking human ovarian tissue at reproductive age. The optimized formulation demonstrated a desirability of 97.5% and exhibited a high follicle survival rate (83%) after 7 days of in vitro culture, supporting follicle development up to the secondary stage. Confocal microscopy confirmed follicle growth, and connexin 43 and Phalloidin staining indicated the retention of connections between granulosa cells and the oocyte. In summary, this PhD thesis presents a comprehensive exploration of PEGylated fibrin hydrogels as a promising biomaterial for encapsulating and supporting isolated human ovarian preantral follicles and cells. Overcoming challenges related to fibrin degradation and achieving a biomechanically tailored formulation, this study holds significant potential for developing engineered ovaries and advancing fertility restoration strategies for cancer patients.
- Affiliations
Citations
Dadashzadeh, A. (2024). Ovary tissue engineering : a strategy to preserve fertility in cancer patients. https://hdl.handle.net/2078.5/237413