Expectations and limitations of ovarian tissue transplantation

De novo design of a nanoregulator for the dynamic restoration of ovarian tissue in cryopreservation and transplantation

The cryopreservation and transplantation of ovarian tissue underscore its paramount importance in safeguarding reproductive capacity and ameliorating reproductive disorders. However, challenges persist in ovarian tissue cryopreservation and transplantation (OTC-T), including the risk of tissue damage and dysfunction. Consequently, there has been a compelling exploration into the realm of nanoregulators to refine and enhance these procedures. This review embarks on a meticulous examination of the intricate anatomical structure of the ovary and its microenvironment, thereby establishing a robust groundwork for the development of nanomodulators. It systematically categorizes nanoregulators and delves deeply into their functions and mechanisms, meticulously tailored for optimizing ovarian tissue cryopreservation and transplantation. Furthermore, the review imparts valuable insights into the practical applications and obstacles encountered in clinical settings associated with OTC-T. Moreover, the review advocates for the utilization of microbially derived nanomodulators as a potent therapeutic intervention in ovarian tissue cryopreservation. The progression of these approaches holds the promise of seamlessly integrating nanoregulators into OTC-T practices, thereby heralding a new era of expansive applications and auspicious prospects in this pivotal domain.

Curcumin and gallic acid have a synergistic protective effect against ovarian surface epithelium and follicle reserve damage caused by autologous intraperitoneal ovary transplantation in rats

The objective of this study to examine the effects of curcumin and gallic acid use against oxidative stress damage in the autologous intraperitoneal ovarian transplantation model created in rats on ovarian follicle reserve, ovarian surface epithelium, and oxidant-antioxidant systems. 42 adult female Sprague Dawley rats (n=7) were allocated into 6 groups. Group 1 served as the control. In Group 2, rats underwent ovarian transplantation (TR) to their peritoneal walls. Group 3 received corn oil (CO) (0.5 ml/day) one day before and 14 days after transplantation. Group 4 was administered curcumin (CUR) (100 mg/kg/day), Group 5 received gallic acid (GA) (20 mg/kg/day), and Group 6 was treated with a combination of curcumin and gallic acid via oral gavage after transplantation. Rats were sacrificed on the 14th postoperative day, and blood along with ovaries were collected for analysis. The removed ovaries were analyzed at light microscopic, fluorescence microscopic, and biochemical levels. In Group 2 and Group 3, while serum and tissue Total Oxidant Levels (TOS) and Oxidative Stress Index (OSI) increased, serum Total Antioxidant Levels (TAS) decreased statistically significantly (p˂0.05) compared to the other groups (Groups 1, 4, 5, and 6). The ovarian follicle reserve was preserved and the changes in the ovarian surface epithelium and histopathological findings were reduced in the antioxidant-treated groups (Groups 4, 5, and 6). In addition, immunofluorescence examination revealed that the expression of Cytochrome C and Caspase 3 was stronger and Ki-67 was weaker in Groups 2 and 3, in comparison to the groups that were given antioxidants. It can be said that curcumin and gallic acid have a histological and biochemical protective effect against ischemia-reperfusion injury due to ovarian transplantation, and this effect is stronger when these two antioxidants are applied together compared to individual use.

Erythropoietin effects on cryopreserved/transplanted cat ovarian tissue: A comparison of two incubation methods

Many feline species are currently threatened with extinction. Therefore, germplasm bank establishment has become imperative. However, cryoinjury and ischemia-reperfusion injury pose significant obstacles to both cryopreservation and xenotransplantation. In this regard, erythropoietin (Epo) represents a potential alternative strategy due to its properties. This study aimed to assess the incubation of domestic cat ovarian tissue in Epo, both before and after cryopreservation, and investigate its effectiveness in promoting revascularization following xenotransplantation. Sixteen ovaries from 8 healthy cats were sliced following elective bilateral ovariohysterectomy (OHE). Subsequently, 8 fragments measuring 3 mm³ each were obtained from the cortical region of each ovary. The fragments were allocated into 3 treatment groups: Cryo group, fragments were cryopreserved, thawed and immediately transplanted; Cryo + Epo group, fragments were first cryopreserved in nitrogen, thawed, incubated in Epo (100 IU) for 2h and transplanted; and the Epo + Cryo group, in which fragments were first incubated in Epo (100 IU) for 2h, cryopreserved, thawed and immediately transplanted. The fragments were then xenotransplanted into the dorsal subcutaneous region of ovariectomized female nude mice and retrieved at 7, 14, 21, and 28 days post-transplantation. The results indicated that Epo effectively enhanced follicular survival, preservation of viability, and tissue revascularization. The Epo + Cryo group displayed better revascularization rates on D14 and D21 post-transplantation and an increase in primordial and growing follicles on D28, the Cryo + Epo group exhibited significantly more follicles on D14 and D21, with fewer degenerated follicles.

Alpha lipoic acid controls degeneration and ensures follicular development in ovine ovarian tissue cultured in vitro

This study aims to evaluate the effects of adding alpha lipoic acid (ALA) to the in vitro ovarian tissue culture medium, either fresh or after vitrification/warming. For this purpose, 10 ovaries from five adult sheep were used. Each pair of ovaries gave rise to 16 fragments and were randomly distributed into two groups: fresh (n = 8) and vitrified (n = 8). Two fresh fragments were fixed immediately and considered the control, while another six were cultured in vitro for 14 days in the absence; presence of a constant (100 μM/0-14 day) or dynamic (50 μM/day 0-7 and 100 μM/day 8-14) concentration of ALA. As for the vitrified fragments, two were fixed and the other six were cultured in vitro under the same conditions described for the fresh group. All the fragments were subjected to morphological evaluation, follicular development and stromal density (classical histology), DNA fragmentation (TUNEL), senescence (Sudan Black), fibrosis (Masson's Trichome), and endoplasmic reticulum stress (immunofluorescence). Measurements of the antioxidant capacity against the free radicals 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and estradiol (E2) levels in the culture medium was performed. The results showed that in the absence of ALA, in vitro culture of vitrified ovarian fragments showed a significant reduction (P < 0.05) in follicular morphology and increased the presence of senescence and tissue fibrosis (P < 0.05). Dynamic ALA maintained E2 levels unchanged (P > 0.05) until the end of vitrified ovarian tissue culture and controlled the levels of ABTS and DPPH radicals in fresh or vitrified cultures. Therefore, it is concluded that ALA should be added to the vitrified ovarian tissue in vitro culture medium to reduce the damage that leads to loss of ovarian function. To ensure steroidogenesis during in vitro culture, ALA should be added dynamically (different concentrations throughout culture).

Effects of different subcutaneous sites on heterotopic autotransplantation of canine ovarian tissue

Ovarian tissue transplantation makes it possible to restore fertility; however, the success of this technique depends on the transplant region used. Therefore, this study aimed to evaluate the effect of two subcutaneous regions on canine ovarian transplantation, pinna (Pi) and neck (Ne), for 7 and 15 days. Ovaries collected by ovariosalpingohysterectomy were fragmented using a punch device. Fresh fragments were fixed, and the others were immediately grafted onto the animal itself in the Pi and Ne regions for 7 and 15 days. Recovered fragments were evaluated for histology (morphology, development and stromal density), picrosirius (collagen fibers), and immunohistochemistry (fibrosis and cell proliferation). The results showed that follicular normality rates were lower in Pi-7 (78%) vs. control (90%) and Pi-15 (86%), similar in Ne-7 (92%) and superior in Ne-15 (97%) compared to the control, with the effect of the region Ne (94%) superior (P < 0.05) to Pi (82%). Stromal density reduced in both regions vs. control but was similar within 15 days. Fragments from both regions showed higher fibronectin labeling and deposition of type I and lower type III collagen fibers (P < 0.05) vs. control. Proliferation rates in Ne-7 were higher (P < 0.05) than in control, and Pi-15 was higher (P < 0.05) than Ne-15. In conclusion, the pinna may be a region with greater potential than the neck after a 15-day autotransplantation of canine ovarian tissue.

Effects of erythropoietin on ischaemia-reperfusion when administered before and after ovarian tissue transplantation in mice

RESEARCH QUESTION

Is the optimal timing for administering erythropoietin to minimize ischaemic injury in ovarian tissue transplantation before ovary removal for cryopreservation and subsequent transplantation or after transplantation?

DESIGN

Thirty Swiss mice (nu/nu) were divided into three groups: treatment control group (n = 10); erythropoietin before harvesting group (EPO-BH) (n = 10) and erythropoietin after transplantation group (EPO-AT) (n = 10). Animals underwent bilateral ovariohysterectomy and their hemiovaries were cryopreserved by slow freezing. At the same time, previously cryopreserved hemiovaries were transplanted subcutaneously in the dorsal region. Erythropoietin (250 IU/kg) and sterile 0.9% saline solution were administered every 12/12 h over 5 consecutive days in the EPO-AT and EPO-BH groups, respectively.

RESULTS

Administration of erythropoietin in the EPO-AT group improved the viability of ovarian follicles, reducing degeneration and increasing the number of morphologically normal growing follicles at 14 days after transplantation compared with the EPO-BH group (P = 0.002). This group also showed higher percentages of proliferative follicles at 7 days after transplantation (P ≤ 0.03), increased blood vessel count (P ≤ 0.03) and greater tissue area occupied by blood vessels at days 7 and 14 after transplantation (P ≤ 0.03), compared with hormone administration before cryopreservation (EPO-BH group) and the treatment control group. Additionally, treatment with erythropoietin before or after transplantation reduced fibrotic areas at 7 days after transplantation (P = 0.004).

CONCLUSION

Erythropoietin treatment after transplantation reduced ischaemic damage in transplanted ovarian tissue, increased angiogenesis, maintenance of ovarian follicle proliferation and reduced fibrosis areas in the grafted tissue.

Recent advances in endocrine organoids for therapeutic application

The endocrine system, consisting of the hypothalamus, pituitary, endocrine glands, and hormones, plays a critical role in hormone metabolic interactions. The complexity of the endocrine system is a significant obstacle to understanding and treating endocrine disorders. Notably, advances in endocrine organoid generation allow a deeper understanding of the endocrine system by providing better comprehension of molecular mechanisms of pathogenesis. Here, we highlight recent advances in endocrine organoids for a wide range of therapeutic applications, from cell transplantation therapy to drug toxicity screening, combined with development in stem cell differentiation and gene editing technologies. In particular, we provide insights into the transplantation of endocrine organoids to reverse endocrine dysfunctions and progress in developing strategies for better engraftments. We also discuss the gap between preclinical and clinical research. Finally, we provide future perspectives for research on endocrine organoids for the development of more effective treatments for endocrine disorders.

Successful Pre-Treatment Ovarian Fresh Tissue Transplantation in a Cervical Cancer Patient Undergoing Radiation Therapy: A Case Report

Cervical cancer is one of the most frequent gynecological malignancies in Brazil, and most of the patients require pelvic radiotherapy as part of oncological treatment. Pelvic radiotherapy induces ovarian premature insufficiency in pre-menopausal women. This condition impacts the life quality and increases the risk of osteoporosis, obesity, cardiovascular, and neurodegenerative diseases in the middle and long term. Most of these patients have no access to hormonal replacement therapy. Techniques such as ovarian transposition have questionable results when aiming to preserve ovarian function. In this context, a promising alternative is the implantation of fresh ovarian tissue, outside the radiotherapy field, in the abdominal cavity (orthotopic implantation) or in other sites such as the forearm, breast, or subcutaneous tissue (heterotopic implantation). Here we report a successful case of autologous implantation of fresh ovarian tissue in the inner thigh of a young patient with advanced cervical cancer, who was a candidate for concurrent chemoradiotherapy.

A comprehensive review and update on human fertility cryopreservation methods and tools

The broad conceptualization of fertility preservation and restoration has become already a major concern in the modern western world since a large number of individuals often face it in the everyday life. Driven by different health conditions and/or social reasons, a variety of patients currently rely on routinely and non-routinely applied assisted reproductive technologies, and mostly on the possibility to cryopreserve gametes and/or gonadal tissues for expanding their reproductive lifespan. This review embraces the data present in human-focused literature regarding the up-to-date methodologies and tools contemporarily applied in IVF laboratories' clinical setting of the oocyte, sperm, and embryo cryopreservation and explores the latest news and issues related to the optimization of methods used in ovarian and testicular tissue cryopreservation.

Fertility preservation for patients with cancer

Background: The survival rate of cancer patients is increasing owing to the early diagnosis and treatment methods. Radiotherapy and chemotherapy may cause serious complications, such as ovarian failure and infertility. In particular, preservation of fertility in women of reproductive age with cancer could improve their quality of life as well as reduce social and psychological pain.Current Concepts: Embryo or oocyte cryopreservation is a method of fertility preservation; however, it cannot be utilized by all women with cancer because of the complications of the condition and treatment method. Ovarian tissue cryopreservation and transplantation enables fertility preservation in those needing immediate cancer treatment, such as chemotherapy or radiotherapy, or those unqualified for ovarian stimulation. A recent review reported that frozen-thawed ovarian transplantation led to approximately 130 live births with a conception rate of approximately 30%. Endocrine function recovery occurred in 92.9% of the patients between 3.5 and 6.5 months after transplantation.Discussion and Conclusion: In this study, we introduced various methods and strategies for improving the outcomes of ovarian tissue cryopreservation and transplantation. These results could serve as a reference for patients and clinicians to choose the best options for fertility preservation based on the patient’s current situation and condition.

The effects of H22 tumor on the quality of oocytes and the development of early embryos from host mice: A single-cell RNA sequencing approach

The association between cancer and female reproduction remains largely unknown. Here we investigated the quality of oocytes and the developmental potential of zygotes using H22 tumor-bearing mice model. The results showed that the number of oocytes was decreased in tumor-bearing mice compared with the control mice, and accompanied scattered chromosomes was observed. Further study revealed an abnormal epigenetic reprogramming occurred in the zygotes from the H22 tumor-bearing mice, as exemplified by the aberrant 5hmC/5mC modifications in the pronuclei. Finally, single-cell RNA sequencing was performed on the oocytes collected from the H22 tumor-bearing mice. Our data showed that 45 of the 202 differentially expressed genes in tumor-bearing group were closely associated with oocyte quality. Protein interaction analysis indicated that the potential interaction among these 45 genes. Collectively, our study uncovered that the quality of oocytes and early embryonic development were affected by H22 tumor bearing via the altered expression patterns of genes related with reproduction, providing new insights into the reproductive capability of female cancer patients.

Metabolic activity in cryopreserved and grafted ovarian tissue using high-resolution respirometry

Cryopreservation of ovarian tissue followed by transplantation represents a strategy to restore ovarian function and fertility. Stress from cryopreservation-thawing processes can lead to alterations and/or damage to mitochondrial structure and functionality. High resolution respirometry and histological analysis were used to evaluate the effect of cryopreservation and transplantation on ovarian tissue. Four different conditions were performed: Fresh non-transplanted tissue, Fresh transplanted tissue, Cryopreserved non-transplanted tissue and Cryopreserved transplanted tissue. All groups were able to respond to the substrates-uncoupler-inhibitor protocol. We found a dramatic decrease in general oxygen consumption in hemi-ovaries submitted to cryopreservation and/or transplantation. The effect of cryopreservation on mitochondrial metabolism was less intense than effect of transplantation, since the transplantation affected all of the mitochondrial states. A total of 2644 follicles were analyzed. Of these, 2198 were classified as morphologically normal. The percentage of morphologically normal follicles was significantly lower in the Cryopreserved transplanted group when compared to the Cryopreserved non-transplanted group and the Fresh transplanted group (p-value < 0.05). Despite decreased follicular viability and mitochondrial activity, the cryopreservation followed by transplantation of ovarian tissue proved feasible for attempts to restore ovarian function.

Effect of Lysophosphatidic Acid on the Vascular Endothelial Growth Factor Expression in Autotransplanted Mouse Ovaries Encapsulated in Sodium Alginate

Objective: The aim of this study was to evaluate the effect of lysophosphatidic acid (LPA) supplementation during in vitro culture and transplantation of mouse ovaries on the follicular development and expression of vascular endothelial growth factor (VEGF) as an angiogenesis factor at the mRNA and protein levels. Materials and methods: Three weeks old mice ovaries were cultured in the presence and absence of LPA for 24 hours, then they were capsulated in sodium alginate in the presence and absence of LPA as four experimental groups. After transplantation the vaginal smears were performed daily to evaluate the initiation of the estrous cycle. The morphology and follicular distribution were analyzed at the first and fourth estrous cycles using hematoxylin and eosin staining. Then in the groups that showed higher and lower follicular development the immunohistochemistry assay was conducted to identify VEGF protein expression, and the real time RT-PCR was done to analyze the expression of Vegf gene at the first estrus cycle. Results: The large size follicles and also the corpus luteum were prominent in all transplanted groups at fourth estrus cycle in comparison with intact control groups. The statistically lowest percentage of small size follicles and the highest percentages of large size follicles were seen in LPA⁺/LPA^- group (p<0.05). The expression ratio of Vegf to β-actin was significantly higher in this group in comparison with non-LPA treated and intact control groups (p <0.05). Conclusion: LPA as an angiogenesis factor increases the follicular development in transplanted ovaries but it causes early discharge of ovarian reserve.

Ectopic autologous transplantation of ovarian tissue as a feasible technique to assess ovarian morphophysiology

The cryopreservation of murine ovarian tissue and its transplantation can be a promising technique for the preservation of fertility and an alternative for the future reconstitution of scientific valuable strains of mice. Accordingly, the aim of this study was to describe the entire surgical procedure for ovariectomy and dorsal subcutaneous autotransplantation in mice, and also some data about the efficiency of this procedure. Female C57Bl/6J mice (n = 18) were anaesthetised and bilaterally ovariectomized. After surgery, ovaries were autotransplanted in small subcutaneous pouches in the dorsal region of the forelimbs. The animals were inspected daily and, 23 days after transplantation, euthanasia and recovery of ovarian tissues were performed. Postoperative recovery, oestrous cyclicity, and folliculogenesis progression were evaluated. At 23 days after transplantation, the recovery of the ovaries was feasible, all classes (primordial to antral) of follicles were observed. Additionally, satisfactory efficiency rates were obtained, with 100% of anaesthesia survival rate, survival, graft recovery, folliculogenesis progression and oestrous cyclicity. In general, this short article describes ovarian ectopic autologous transplantation as an effective technique for maintaining rodent oogenesis and endocrine ovarian function. Even more broadly, we can still assume that the application of this technique may reduce the number of breeding matrices and experimental animals in the near future.

Applying plastic surgery principles to ovarian tissue transplantation

Ovarian tissue cryopreservation (OTC) and transplantation is an innovative procedure increasingly utilized to help preserve fertility after gonadotoxic treatments especially in cancer patients. Approximately 30% of autotransplanted patients are able to achieve live birth, typically with the help of in-vitro fertilization. Numerous techniques and grafting sites have been described to continue to increase this figure. In the field of plastic surgery, tissue grafting has been successful performed for thousands of years and knowledge in this area has been significantly refined. A qualitative review of the literature using PubMed, Cochrane, SCOPUS and Medline databases was performed to look for articles relating to ovarian tissue transplantation (OTT) and comparisons made to plastic surgery tissue grafting. Many parallels were found between the principles of grafting in plastic surgery and the principles of OTT, including pre-operative patient optimization, suitable donor site selection, tissue harvest and preparation, graft site choice, immobilization of the graft and post-operative care. Consideration of the benefits and risks of using orthotopic versus heterotopic recipient sites is also highly important with regards to graft take, morbidity and ease of access of oocyte collection. We believe that ongoing discussion between disciplines can have the potential to improve knowledge, surgical techniques and patient outcomes.

Current and Future Perspectives for Improving Ovarian Tissue Cryopreservation and Transplantation Outcomes for Cancer Patients

Although advances in cancer treatment and early diagnosis have significantly improved cancer survival rates, cancer therapies can cause serious side effects, including ovarian failure and infertility, in women of reproductive age. Infertility following cancer treatment can have significant adverse effects on the quality of life. However, established methods for fertility preservation, including embryo or oocyte cryopreservation, are not always suitable for female cancer patients because of complicated individual conditions and treatment methods. Ovarian tissue cryopreservation and transplantation is a promising option for fertility preservation in pre-pubertal girls and adult patients with cancer who require immediate treatment, or who are not eligible to undergo ovarian stimulation. This review introduces various methods and strategies to improve ovarian tissue cryopreservation and transplantation outcomes, to help patients and clinicians choose the best option when considering the potential complexity of a patient's situation. Effective multidisciplinary oncofertility strategies, involving the inclusion of a highly skilled and experienced oncofertility team that considers cryopreservation methods, thawing processes and devices, surgical procedures for transplantation, and advances in technologies, are necessary to provide high-quality care to a cancer patient.

Heterotopic autotransplantation of equine ovarian tissue using intramuscular versus subvulvar grafting sites: Preliminary results

Ovarian tissue transplantation (OTT) is a technique well established and successfully applied in humans using mainly orthotopic or heterotopic transplantation sites. In livestock, OTT is still in its infancy and, therefore, different aspects of the technique, including the efficiency of different heterotopic OTT sites as well as the potential effect of age (i.e., young vs. old mares) in the ovarian graft quality, need to be investigated. The present study investigated the efficacy of the intramuscular (IM) or the novel subvulvar mucosa (SV) heterotopic autotransplantation sites to maintain the survivability of the grafts for 3 and 7 days post-OTT. Ovarian biopsy fragments were obtained in vivo and distributed to the following treatments: Fresh control group (ovarian fragments immediately fixed), SV-3, IM-3, SV-7, and IM-7. During and after graft harvesting, the macroscopic characteristics of the grafts (i.e., adherence, morphology, and bleeding) were scored, and the percentages of morphologically normal and developing preantral follicles as well as the follicular and stromal cell densities of the grafts were evaluated. The results were that similar (P > 0.05) macroscopic scores were observed between both transplantation sites 7 days post-OTT, with positive correlations (P < 0.01) found among adherence, morphology, and bleeding of the grafts. A lower (P < 0.05) percentage of morphologically normal follicles was found 7 days post-OTT in the SV site (82%) compared with the Fresh control group (99%) and IM site (95%); however, the percentages of developing follicles were similar (P > 0.05) between both transplantation sites 7 days post-OTT (30-43%). Although similar (P > 0.05) follicular densities were found in both transplantation sites in young and old mares at 3 and 7 days post-OTT, large individual variation in the follicular depletion rate was observed regardless of transplantation site. The Fresh control group and SV-7 treatments had higher (P < 0.05) stromal cell densities in young and old mares compared with both IM-7 treatments. When comparing transplant sites between young and old mares, the follicular density in old mares and the stromal cell density in young mares were greater (P < 0.05) in the SV than in the IM site. In conclusion, even though the transplantation sites differentially affected some end points, overall comparable findings of the OTT technique using both heterotopic autotransplantation sites (i.e., IM and SV) for equine ovarian tissue were observed.

Ovarian tissue grafting: Lessons learnt from our experience with 55 grafts

Purpose

Uncertainties remain regarding the clinical efficacy of ovarian tissue cryopreservation and grafting. We report a retrospective analysis of reproductive outcomes and lessons learnt following 55 ovarian tissue transplant procedures at our center from 2006 to 2019.

Methods

We analyzed variables related to graft success such as tissue volume, follicular density, total follicular volume, and age on the duration of graft function.

Results

Follicular density and total follicular volume correlate positively with duration of graft function. All clinical pregnancies in our cohort occurred in women who were aged 35 or less at the time of ovarian tissue cryopreservation.

Conclusion

Graft success, as determined by eventual pregnancy and the longevity of graft function, may be impacted by factors including age at cryopreservation, follicular density, and total follicular volume.

Does open ovarian biopsy in prepubertal age affect ovarian reserve in a rat model?

BACKGROUND

Partial resection of the ovary carries a possible risk of fertility reduction. We studied the influence of open ovarian biopsy on ovarian reserve, including anti-Müllerian hormone and follicle-stimulating hormone serum level evaluation, in a prepubertal rat model.

METHODS

Interventions - the initial surgery was unilateral ovarian biopsy (38 rats, group B1, B2) or unilateral ovarian biopsy and ovarian resection of the contralateral gonad (38 rats, group BR1, BR2). The second operation was bilateral ovarian resection and total resection of the remaining ovary. All rats had hormone serum levels evaluated. The control group had only a blood test taken and bilateral ovarian resection done at the second intervention (30 rats, group C1, C2). The collected tissue was examined estimating follicle count and anti-Müllerian hormone immunoexpression.

RESULTS

Anti-Müllerian hormone levels were significantly lower at the second intervention in the group BR2 but significantly higher in the group C2. Follicle-stimulating hormone levels were significantly higher in all but one group (BR2).

CONCLUSIONS

Biopsy itself might not reduce ovarian reserve if done properly but we should know its possible negative effects in the case of a single remaining ovary.

Comparison of the effects of three cryoprotectants on the cryopreservation of mouse subcutaneous tissue under different conditions

The subcutaneous tissue of animals contains different cell types, and different cells have different requirements for cryopreservation. This establishes obstacles that need to be overcome in the clinical application of tissue preservation. In the present study, the effects of different freezing rates and various concentrations of cryoprotectants on the cryopreservation of subcutaneous tissue of mice were compared, and these results provided basic research data that can be used to explore the optimal cryopreservation method for tissue. The effects of three cryoprotectants, dimethyl sulfoxide, glycerinum and 1,2-propanediol, and their concentrations on the cryopreservation of subcutaneous tissue of mice were compared with slow and rapid freezing rates. The results revealed that under various cryopreservation conditions, the percentage of fibroblasts that grow from the tissue following slow cryopreservation (19.8%) was significantly higher than that following rapid freezing (6.7%) at osmotic equilibrium for 10-20 min (P<0.05). After 19 days of culture, under the conditions of slow freezing, with 10, 20 and 30% glycerinum as a cryoprotectant, respectively, fibroblasts grew from 26.0, 16.7 and 16.7% of the tissues, respectively. No fibroblasts were indicated in the tissue mass cultured in any other tissue blocks treated with cryopreservation solutions. Under the condition of rapid freezing, fibroblasts grew from 6.7 and 6.7% tissue blocks of 20% DMSO and 10% glycerinum, respectively, following 19 days of culture. No fibroblasts were identified in the tissue mass cultured in the other tissue blocks treated with cryopreservation solutions, and no fibroblasts were identified in the tissue blocks without osmotic balance before freezing.

Investigation on revascularization time and initial damage after transplantation of fresh and cryopreserved ovarian tissue in domestic cats

The present study evaluated revascularization time of fresh and cryopreserved cat ovarian tissue after transplantation to subcutaneous tissue. Ovaries of five cats were used and eight pieces of ovarian tissue were taken from each pair of ovaries. Immediately after removal, three pieces were transplanted and one fixed for fresh control. The remaining four pieces were cryopreserved and, after thawing, one was fixed for cryopreservation control and three were transplanted. Grafts were recovered on days 2 (D2), 4 (D4) and 6 (D6) post-transplantation. Blood vessels were identified by immunohistochemistry and doppler ultrasound. Immunohistochemistry showed that the percentages of total tissue area occupied by blood vessels were similar (P > 0.05) in fresh and cryopreserved tissues. In both cases, blood vessel area was significantly higher (P < 0.05) on D4 and D6 compared to D0. Ultrasound analysis showed vascularization improvement on the periphery of grafts from D2 to D4 and from D4 to D6, both in fresh and cryopreserved tissue samples. Nonetheless, there was a significant decrease (P < 0.05) in the percentage of morphologically normal follicles (MNF) after transplantation compared to non-transplanted tissue (D0), both for fresh and cryopreserved samples. Moreover, the number of follicles found in samples was considerably smaller after grafting. In conclusion, revascularization of ovarian tissue autotransplanted to subcutaneous tissue in domestic cats occurs within 4 days after transplantation, both for fresh and cryopreserved tissue. However, large follicular loss has been observed in the first days post-transplantation, especially in cryopreserved tissues.

Supplementation of Culture Media with Lysophosphatidic Acid Improves The Follicular Development of Human Ovarian Tissue after Xenotransplantaion into The Back Muscle of γ-Irradiated Mice

Objective

The aim of the present study was to evaluate the effects of lysophosphatidic acid (LPA) supplementation of human ovarian tissue culture media on tissue survival, follicular development and expression of apoptotic genes following xenotransplantation.

Materials and Methods

In this experimental study, human ovarian tissue was collected from eight normal female to male transsexual individuals and cut into small fragments. These fragments were vitrified-warmed and cultured for 24 hours in the presence or absence of LPA, then xenografted into back muscles of γ-irradiated mice. Two weeks post-transplantation the morphology of the recovered tissues were evaluated by hematoxylin and eosin staining. The expression of genes related to apoptosis (BAX and BCL2) were analyzed by real time revers transcription polymerase chain reaction (RT-PCR) and detection of BAX protein was done by immunohistochemical staining.

Results

The percent of normal and growing follicles were significantly increased in both grafted groups in comparison to the non-grafted groups, however, these rates were higher in the LPA-treated group than the non-treated group (P<0.05). There was a higher expression of the anti-apoptotic gene, BCL2, but a lower expression of the pro-apoptotic gene, BAX, and a significant lower BAX/ BCL2 ratio in the LPA-treated group in comparison with non-treated control group (P<0.05). No immunostaining positive cells for BAX were observed in the follicles and oocytes in both transplanted ovarian groups.

Conclusion

Supplementation of human ovarian tissue culture medium with LPA improves follicular survival and development by promoting an anti-apoptotic balance in transcription of BCL2 and BAX genes.

Function of Cryopreserved Cat Ovarian Tissue after Autotransplantation

Simple Summary

Assisted reproduction techniques are potentially important tools for the creation of gene banks largely focused on preserving female germ cells and tissues, cryopreservation being one of the most important. Since there is not yet a protocol established for the preservation of cat ovarian tissue, we decided to assess our cryopreservation protocol with autotransplantation of the ovary. Our study showed that even though follicular survival was low, follicles were able to survive up to 28 days of transplantation and develop up to the antral stage, which helps elucidate the path for preservation of felid ovaries. Once this technique is improved, it may contribute to the preservation of wild feline species.

Abstract

The aim of this study was to assess a slow-freezing protocol of cat ovarian tissue cryopreservation using autotransplantation. Four adult queens were ovariohysterectomized and the ovaries were fragmented and cryopreserved. After one week, the grafts were thawed and autografted to the subcutaneous tissue of the dorsal neck of each queen, then randomly removed after 7, 14, 28, 49, and 63 days after transplantation. Percentages of morphologically normal primordial and growing follicles (MNFs) were 88% and 97%, respectively, in fresh tissue samples (fresh controls), and 74% and 100%, respectively, immediately after thawing (cryo D0). No MNFs were found after 49 days of transplantation. In both fresh control and cryo D0 fragments, granulosa cells were frequently in proliferation. Two morphologically normal antral follicles were detected in one queen on Day 28 post-transplantation. Connective tissue fibers increased, suggesting replacement of active ovarian cortex by fibrous tissue. Tissue vascularization was observed at 7 days after grafting, and wide blood vessels were clearly visible on Days 49 and 63. In conclusion, although follicular survival was low after cryopreservation and grafting of cat ovarian tissue, follicles were able to develop up to the antral stage, which is an encouraging outcome.

Development of Ovarian Tissue Autograft to Restore Ovarian Function: Protocol for a French Multicenter Cohort Study

Background

Sterility is a major late effect of radiotherapy and chemotherapy treatments. Iatrogenic sterility is often permanent and greatly impacts long-term quality of life. Ovarian tissue cryopreservation (OTC) performed before gonadotoxic treatments with subsequent autograft is a method of fertility preservation available for girls and women. Its application in prepubertal girls is of particular value as it is the only possible approach in this patient group. In addition, it does not require a delay in cancer therapy and no ovarian stimulation is needed.

Objective

The primary aim of this protocol is to help increase the implementation of ovarian tissue autografting in France. Knowledge is still lacking regarding the efficacy of ovarian transplantation in restoring ovarian function and regarding the safety of this procedure, especially the risk of cancer cell reseeding in certain types of cancer. A secondary aim of this study is to generate data to improve our understanding of these two essential aspects.

Methods

The DATOR (Development of Ovarian Tissue Autograft in Order to Restore Ovarian Function) study is ongoing in 17 university hospitals. The DATOR protocol includes the autograft of ovarian cortex fragments. Candidates are identified from an observational prospective cohort (called the Prospective Cohort of Patients Candidates for Ovarian Tissue Autograft [PERIDATOR]) of patients who have undergone OTC. Enrollment in the study is initiated at the patient’s request and must be validated by the center’s multidisciplinary team and by the study steering committee. The DATOR study begins with a total medical checkup. Ovarian tissue qualification and residual disease detection, if required, are performed.

Results

The study is ongoing. Currently, 38 patients have provided informed consent and have been entered into the DATOR study. Graft has been performed for 34 of these patients. An interim analysis was conducted on the first 25 patients for whom the period of at least 1 year posttransplantation was achieved. Out of these 25 patients, 11 women succeeded in becoming pregnant (pregnancy rate=44% [11/25]; delivery rate=40% [10/25]). Among these, 6 women conceived twice, and 1 pregnancy led to a miscarriage.

Conclusions

Our preliminary analysis appears to be coherent with the accumulating body of evidence indicating the potential utility of ovarian tissue autograft for patients with premature ovarian failure. All these elements justify the pursuit of our study.

Trial Registration

ClinicalTrials.gov NCT02846064; https://clinicaltrials.gov/ct2/show/NCT02846064

International Registered Report Identifier (IRRID)

DERR1-10.2196/12944

Ovarian Tissue Transplantation: Experience From Germany and Worldwide Efficacy

Extraction of ovarian tissue prior to oncologic therapy and subsequent transplantation is being performed increasingly often to preserve fertility in women. The procedure can be performed at any time of the cycle and, therefore, generally does not lead to any delay in oncological therapy. Success rates with transplantation of cryopreserved ovarian tissue have reached promising levels. More than 130 live births have been reported worldwide with the aid of cryopreserved ovarian tissue and the estimated birth rate is currently approximately 30%. In Germany, Austria, and Switzerland, the FertiPROTEKT consortium has successfully achieved 21 pregnancies and 17 deliveries generated after 95 ovarian tissue transplantations by 2015, one of the largest case series worldwide confirming that ovarian tissue cryopreservation and transplantation are successful. Approximately, more than 400 ovarian tissue cryopreservation procedures are performed each year in the FertiPROTEKT consortium, and the request and operations for ovarian tissue transplantation have increased in recent years. Therefore, recommendations for managing transplantation of ovarian tissue to German-speaking reproductive medicine centers were developed. In this overview, these recommendations and our experience in ovarian tissue transplantation are presented and discussed with international procedures.

Fertility preservation in patients with hematologic malignancies and recipients of hematopoietic cell transplants

Patients with hematologic malignancies and those undergoing hematopoietic cell transplantation (HCT) face a complex set of challenges when considering options for fertility preservation (FP). There are no standard options for prepubertal children, and women with hematologic malignancies may not be eligible for standard FP options. Fortunately, initial therapies for most blood cancers are not highly gonadotoxic, affording an important opportunity for postremission counseling and referrals to fertility specialists. These patients face a high risk of relapse, and many will be referred for autologous or allogeneic HCT, which carries an extremely high risk of infertility. The expanding indications for HCT to include benign hematologic disorders as well as autoimmune diseases mandate that all hematologists are familiar with these risks. Oncofertility researchers are continually pushing the boundaries of what may be possible for our patients; in the meantime, communication and shared decision-making between hematologists and patients, as well as program-building, education, and outreach are essential to ensure that these patients, many of whom will be cured, maintain all of their options for a fulfilling life after intensive therapy.

Fertility Preservation: Current and Future Perspectives for Oncologic Patients at Risk for Iatrogenic Premature Ovarian Insufficiency

Progress in recent years in the efficacy of oncologic treatment and early diagnosis of cancer has determined an increase in life expectance in cancer patients. About 10% of all cancer cases affect women younger than 45 years; therefore nowadays approximately 5-6% of the population in childbearing age consists in cancer survivors. A crucial issue is the high risk of premature ovarian insufficiency due to possible gonadotoxic effects of oncologic treatments. Considering combined chemotherapy, radiation therapy, and bone marrow transplantation, this risk can reach 92-100%, depending on the age and ovarian reserve of the patient, as well as the schedule and type of therapy. International guidelines recommend addressing all the patients diagnosed with a neoplasia treatable with potentially gonadotoxic therapies to fertility preservation. Moreover, fertility preservation also seems to reserve fascinating implications for women who want to delay childbearing for social reasons or women affected with endometriosis, who could receive unexpected opportunities. At present, the most widespread techniques to preserve fertility in adult women are embryo or oocyte cryopreservation, depending on the presence of a partner or according to legislative issues, but these procedures require time for ovarian stimulation. In prepubertal patients or when there is no possibility of delaying chemotherapy, ovarian tissue cryopreservation and subsequent transplantation represent the main strategy.

Transient inhibition of p53 homologs protects ovarian function from two distinct apoptotic pathways triggered by anticancer therapies

Platinum-based chemotherapies can result in ovarian insufficiency by reducing the ovarian reserve, a reduction believed to result from apoptosis of immature oocytes via activation/phosphorylation of TAp63α by multiple kinases including CHEK2, CK1, and ABL1. Here we demonstrate that cisplatin (CDDP) induces oocyte apoptosis through a novel pathway and that temporary repression of this pathway fully preserves ovarian function in vivo. Although ABL kinase inhibitors effectively block CDDP-induced apoptosis of oocytes, oocytic ABL1, and ABL2 are dispensable for damage-induced apoptosis. Instead, CDDP activates TAp63α through the ATR > CHEK1 pathway independent of TAp63α hyper-phosphorylation, whereas X-irradiation activates the ATM > CHEK2 > TAp63α-hyper-phosphorylation pathway. Furthermore, oocyte-specific deletion of Trp73 partially protects oocytes from CDDP but not from X-ray, highlighting the fundamental differences of two pathways. Nevertheless, temporary repression of DNA damage response by a kinase inhibitor that attenuates phosphorylation of ATM, ATR, CHEK1, and CHEK2 fully preserves fertility in female mice against CDDP as well as X-ray. Our current study establishes the molecular basis and feasibility of adjuvant therapies to protect ovarian function against two distinctive gonadotoxic therapeutics, CDDP, and ionizing radiation.

Ovarian tissue cryopreservation and transplantation in patients with cancer

Chemotherapy and radiotherapy improved survival rates of patients with cancer. However, they can cause ovarian failure and infertility in women of reproductive age. Infertility following cancer treatment is considered a major quality of life issue. Ovarian tissue cryopreservation and transplantation is an important option for fertility preservation in adult patients with cancer who need immediate chemotherapy or do not want to undergo ovarian stimulation. Ovarian tissue freezing is the only option for preserving the fertility of prepubertal patients with cancer. In a recent review, it was reported that frozen-thawed ovarian transplantation has lead to about 90 live births and the conception rate was about 30%. Endocrine function recovery was observed in 92.9% between 3.5 and 6.5 months after transplantation. Based on our review, ovarian tissue cryopreservation and transplantation may be carefully considered before cancer treatment in order to preserve fertility and endocrine function in young cancer survivors.