Cryopreservation of ovarian tissue for fertility preservation in young female oncological patients

FGF2, LIF, and IGF1 (FLI) supplementation during human in vitro maturation enhances markers of gamete competence

STUDY QUESTION

Does a chemically defined maturation medium supplemented with FGF2, LIF, and IGF1 (FLI) improve in vitro maturation (IVM) of cumulus-oocyte complexes (COCs) obtained from children, adolescents, and young adults undergoing ovarian tissue cryopreservation (OTC)?

SUMMARY ANSWER

Although FLI supplementation did not increase the incidence of oocyte meiotic maturation during human IVM, it significantly improved quality outcomes, including increased cumulus cell expansion and mitogen-activated protein kinase (MAPK) expression as well as enhanced transzonal projection retraction.

WHAT IS KNOWN ALREADY

During OTC, COCs, and denuded oocytes from small antral follicles are released into the processing media. Recovery and IVM of these COCs is emerging as a complementary technique to maximize the fertility preservation potential of the tissue. However, the success of IVM is low, especially in the pediatric population. Supplementation of IVM medium with FLI quadruples the efficiency of pig production through improved oocyte maturation, but whether a similar benefit occurs in humans has not been investigated.

STUDY DESIGN, SIZE, DURATION

This study enrolled 75 participants between January 2018 and December 2021 undergoing clinical fertility preservation through the Fertility & Hormone Preservation & Restoration Program at the Ann & Robert H. Lurie Children's Hospital of Chicago. Participants donated OTC media, accumulated during tissue processing, for research.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants who underwent OTC and include a pediatric population that encompassed children, adolescents, and young adults ≤22 years old. All participant COCs and denuded oocytes were recovered from media following ovarian tissue processing. IVM was then performed in either a standard medium (oocyte maturation medium) or one supplemented with FLI (FGF2; 40 ng/ml, LIF; 20 ng/ml, and IGF1; 20 ng/ml). IVM outcomes included meiotic progression, cumulus cell expansion, transzonal projection retraction, and detection of MAPK protein expression.

MAIN RESULTS AND THE ROLE OF CHANCE

The median age of participants was 6.3 years, with 65% of them classified as prepubertal by Tanner staging. Approximately 60% of participants had been exposed to chemotherapy and/or radiation prior to OTC. On average 4.7 ± 1 COCs and/or denuded oocytes per participant were recovered from the OTC media. COCs (N = 41) and denuded oocytes (N = 29) were used for IVM (42 h) in a standard or FLI-supplemented maturation medium. The incidence of meiotic maturation was similar between cohorts (COCs: 25.0% vs 28.6% metaphase II arrested eggs in Control vs FLI; denuded oocytes: 0% vs 5.3% in Control vs FLI). However, cumulus cell expansion was 1.9-fold greater in COCs matured in FLI-containing medium relative to Controls and transzonal projection retraction was more pronounced (2.45 ± 0.50 vs 1.16 ± 0.78 projections in Control vs FLIat 16 h). Additionally, MAPK expression was significantly higher in cumulus cells obtained from COCs matured in FLI medium for 16-18 h (chemiluminescence corrected area 621,678 vs 2,019,575 a.u., P = 0.03).

LIMITATIONS, REASONS FOR CAUTION

Our samples are from human participants who exhibited heterogeneity with respect to age, diagnosis, and previous treatment history. Future studies with larger sample sizes, including adult participants, are warranted to determine the mechanism by which FLI induces MAPK expression and activation. Moreover, studies that evaluate the developmental competence of eggs derived from FLI treatment, including assessment of embryos as outcome measures, will be required prior to clinical translation.

WIDER IMPLICATIONS OF THE FINDINGS

FLI supplementation may have a conserved beneficial effect on IVM for children, adolescents, and young adults spanning the agricultural setting to clinical fertility preservation.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by Department of Obstetrics and Gynecology startup funds (F.E.D.), Department of Surgery Faculty Practice Plan Grant and the Fertility & Hormone Preservation & Restoration Program at the Ann & Robert H. Lurie Children's Hospital of Chicago (M.M.L. and E.E.R.). M.M.L. is a Gesualdo Foundation Research Scholar. Y.Y.'s research is supported by the internal research funds provided by Colorado Center of Reproductive Medicine. Y.Y., L.D.S., R.M.R., and R.S.P. have a patent pending for FLI. The remaining authors have no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Advances of xenogeneic ovarian extracellular matrix hydrogels for in vitro follicle development and oocyte maturation

Research aimed at preserving female fertility is increasingly using bioengineering techniques to develop new platforms capable of supporting ovarian cell function in vitro and in vivo. Natural hydrogels (alginate, collagen, and fibrin) have been the most exploited approaches; however they are biologically inert and/or biochemically simple. Thus, establishing a suitable biomimetic hydrogel from decellularized ovarian cortex (OC) extracellular matrix (OvaECM) could provide a complex native biomaterial for follicle development and oocyte maturation. The objectives of this work were (i) to establish an optimal protocol to decellularize and solubilize bovine OC, (ii) to characterize the histological, molecular, ultrastructural, and proteomic properties of the resulting tissue and hydrogel, and (iii) to assess its biocompatibility and adequacy for murine in vitro follicle growth (IVFG). Sodium dodecyl sulfate was identified as the best detergent to develop bovine OvaECM hydrogels. Hydrogels added into standard media or used as plate coatings were employed for IVFG and oocyte maturation. Follicle growth, survival, hormone production, and oocyte maturation and developmental competence were evaluated. OvaECM hydrogel-supplemented media best supported follicle survival, expansion, and hormone production, while the coatings provided more mature and competent oocytes. Overall, the findings support the xenogeneic use of OvaECM hydrogels for future human female reproductive bioengineering.

Ovarian tissue cryopreservation in young females with cancer and its impact on ovarian follicle density

BACKGROUND

Cancer therapy in young females results in irreversible damage to their ovaries potentially leading to premature ovarian failure (POF) and infertility. Ovarian follicle density (FD) serves as a key predictor of reproductive potential for a woman. FD is significantly reduced after cryopreservation in adult women with cancer. FD in young females with cancer has not been investigated. The specific aim of this study was to assess the efficacy of ovarian tissue cyropreservation (OTC) in young females with cancer by evaluating its impact on FD.

METHODS

An IRB approved prospective human and animal trial enrolled girls (ages 6-18 years) with cancer at high risk for POF from July 1, 2012 through June 30, 2018. All participants underwent pre-operative ultrasounds evaluating their ovaries.  Following a normal ultrasound, each patient underwent a left ovarian tissue harvest prior to cancer therapy. The ovarian tissue was sectioned for use in pathologic analysis, fertility preservation and xenotransplantation before and after cryopreservation. Comparative statistical analyses of the means of FD before and after cryopreservation were implemented using mixed regression modeling that accounted for the correlation among samples from the same patient and differences in age.

RESULTS

Six girls were enrolled (mean, 12 years; median, 13 years, range, 6-17 years). Pathologic analysis was carried out in all viable grafts and ovarian follicle densities were determined. Mean ovarian follicle density (+/- SEM) before cryopreservation was 50.5 +/- 4.26 follicles/mm² and after cryopreservation was 44.1 +/- 4.25 follicles/mm², p < 0.001. Following cryopreservation, on average the ovarian tissue retained 89.0.% of the FD of paired fresh samples (95% CI 82.8%, 95.2%).

CONCLUSIONS

FD in young females with cancer is significantly reduced following OTC. However, the degree of reduction may be less than that reported in adult women. This is the first study in adolescent girls to provide histologic evidence of preservation of ovarian follicle density and potential efficacy of the ovarian tissue cryopreservation strategy.  By providing this evidence base, the potential benefit to young females with cancer and their family may be prognostically and clinically significant.

Hormonal Characteristics of Women Receiving Ovarian Tissue Transplantation with or without Endogenous Ovarian Activity

Ovarian tissue cryopreservation (OTC) and transplantation of frozen/thawed ovarian tissue (OTT) are used for fertility preservation in girls and women. Here, we evaluated the hormonal characteristics of women with or without postmenopausal levels of FSH at the time of OTT to study differences and conditions that best support the initiation of ovarian function. A total of 74 women undergoing OTT (n = 51 with menopausal levels of FSH; n = 23 with premenopausal levels) were followed by measurements of FSH, LH, AMH, and oestradiol. Concentrations of FSH and LH returned to premenopausal levels after 20 weeks on average, with a concomitant increase in oestradiol. Despite resumption of ovarian activity, AMH concentrations were in most instances below the detection limit in the menopausal group, suggesting a low ovarian reserve. Despite a higher age in the premenopausal group, they more often experienced an AMH increase than the menopausal group, suggesting that conditions in the premenopausal ovary better sustain follicle survival, perhaps due to the higher concentrations of oestradiol. Collectively, this study highlights the need for improving follicle survival after OTT. Age and the amount of tissue transplanted are important factors that influence the ability to regain ovarian activity and levels of FSH may need to be downregulated and oestradiol increased prior to OTT.

Hormonal response in patients transplanted with cryopreserved ovarian tissue is independent of whether freezing was performed in childhood or adulthood

PURPOSE

This study evaluated the concentrations of hormones resulting from the transplantation of ovarian tissue (OTT) in relation to whether the tissue was frozen at a time close to puberty or above the age of 19 years.

METHODS

Six girls and adolescents (aged 9-14 years) who underwent ovarian tissue cryopreservation (OTC) were followed after transplantation in adulthood. After OTT, the women were followed via regular blood samples to evaluate the concentrations of FSH, LH, oestradiol and AMH. Twenty-three women undergoing OTT (aged 19-36 years at the time of OTC) were included as a reference group. All of the women had postmenopausal levels of gonadotropins at the time of transplantation.

RESULTS

The return of FSH and LH to normal premenopausal concentrations in adult women transplanted with ovarian tissue that was frozen at a time close to puberty was similar to the profiles in women from the reference group. Serum AMH levels were below the detection limit (via the Roche Elecsys assay) in many samples, but four out of six young girls showed measurable concentrations. Oestradiol similarly increased in the first 12 weeks following transplantation, after which it tended to be higher in women having frozen tissue in adulthood.

CONCLUSIONS

Ovarian tissue that was excised from girls at a time close to puberty, after which it was frozen and transplanted in adulthood, interacts with pituitary tissue in a similar manner to ovarian tissue that is frozen from adult women. Follicles located in the ovarian tissue from young girls are equally sensitive to gonadotropin stimulation as follicles from adult women when exposed to postmenopausal levels of gonadotropins. This result indicates that it is not the ovaries that require maturation to sustain full reproductive potential but rather proper FSH and LH stimulation. Moreover, these results support the continued use of OTC in young women.

Effects of Er:YAG laser treatment on re-vascularization and follicle survival in frozen/thawed human ovarian cortex transplanted to immunodeficient mice

PURPOSE

The huge loss of ovarian follicles after transplantation of frozen/thawed ovarian tissue is considered a major drawback on the efficacy of the procedure. Here we investigate whether Er:YAG laser treatment prior to xenotransplantation can improve re-vascularization and subsequently follicle survival in human ovarian tissue.

METHODS

A total of 99 frozen/thawed human ovarian cortex pieces were included of which 72 pieces from 12 woman were transplanted to immunodeficient mice. Tissues from each woman were included in both an 8-day and an 8-week duration study and treated with either full-beam laser (L1) or fractionated laser (L2), or served as untreated controls. Vascularization of the ovarian xenografts were evaluated after 8 days by qPCR and murine Cd31 immunohistochemical analysis. Follicle densities were evaluated histologically 8 weeks after xenografting.

RESULTS

Gene expression of Vegf/VEGF was upregulated after L1 treatment (p=0.002, p=0.07, respectively), whereas Angpt1, Angpt2, Tnf-α, and Il1-β were significantly downregulated. No change in gene expression was found in Cd31/CD31, ANGPT1, ANGPT2, ANGTPL4, XBP1, or LRG1 after any of the laser treatments. The fraction of Cd31 positive cells were significantly reduced after L1 and L2 treatment (p<0.0001; p=0.0003, respectively), compared to controls. An overall negative effect of laser treatment was detected on follicle density (p=0.03).

CONCLUSIONS

Er:YAG laser treatment did not improve re-vascularization or follicle survival in human ovarian xenografts after 8 days and 8 weeks grafting, respectively. However, further studies are needed to fully explore the potential angiogenic effects of controlled tissue damage using different intensities or lasers.

In vitro growth and maturation of primordial follicles and immature oocytes

Cryopreservation of ovarian tissue to preserve the fertility of girls and young women at high risk of sterility is now widely practiced. Pieces of cryopreserved ovarian cortex can be thawed and autografted to restore fertility, but because of the risks of reintroduction of the cancer, transplantation may not be possible for girls and women with blood-borne leukemias or cancers with a high risk of ovarian metastasis. Cryopreserved ovarian tissue contains mainly primordial follicles but also provides access to immature oocytes from small antral follicles, which may be matured in vitro to provide an additional source of mature oocytes. So in cases in which transplantation is contraindicated, fertility restoration could be safely achieved in the laboratory either by in vitro maturation (IVM) of oocytes aspirated from growing follicles or by the complete in vitro growth (IVG) and maturation (IVM) of primordial follicles to produce fertile metaphase II (MII) oocytes. The development of IVM and IVG methods to support all stages of oocytes available within ovarian tissue will maximize the potential for all patients undergoing fertility preservation.

High Variability of Molecular Isoforms of AMH in Follicular Fluid and Granulosa Cells From Human Small Antral Follicles

Anti-Müllerian hormone (AMH) is a member of the TGF-β superfamily produced by follicular granulosa cells (GCs) in women from late gestation to the end of reproductive life. AMH is thought to inhibit aromatase (i.e., CYP19) expression and decrease the conversion of androgens to oestrogens, especially in small antral follicles before dominance is achieved. Thus, AMH acts as a gatekeeper of ovarian steroidogenesis. However, the exact function and processing of AMH has not been fully elucidated. The present study measured and determined AMH isoforms in human follicular fluid (FF) from small antral follicles and in human GCs using four ELISAs, western blot, and immunofluorescence analysis. We evaluated the presence of the following isoforms: full-length AMH precursor (proAMH), cleaved associated AMH (AMH_N,C), N-terminal pro-region (AMH_N), and active C-terminal (AMH_C) AMH. A negative correlation between follicle diameter and the AMH forms was detected. Moreover, western blot analysis detected various AMH forms in both FFs and GCs, which did not match our consensus forms, suggesting an unknown proteolytic processing of AMH. The presence of these new molecular weight isoforms of AMH differs between individual follicles of identical size in the same woman. This study detected several AMH forms in FF and GCs obtained from human small antral follicles, which suggests that intrafollicular processing of AMH is complex and variable. Thus, it may be difficult to develop an antibody-based AMH assay that detects all AMH isoforms. Furthermore, the variability between follicles suggests that designing a recombinant AMH standard will be difficult.

Primordial follicle survival of goat ovarian tissue after vitrification and transplantation on chorioallanthoic membrane

Background

Ovarian tissue vitrification is an alternative fertility preservation procedure for young female patients prior to gonadotoxic treatment. Primordial follicle loss might be a potential issue for vitrification and transplantation procedures. This study aimed to evaluate primordial follicle density and deoxyribonucleic acid (DNA) fragmentation in each stage of the preservation procedure of goat ovarian tissue. Follicle density and DNA fragmentation were examined microscopically after staining with hematoxylin eosin and TUNEL assay, respectively. Both parameters were compared between fresh, fresh-transplanted, vitrification, and vitrification-transplanted groups.

Results

A significant decrease was observed in the primordial follicle proportion after vitrification and transplantation compared to the primordial follicle proportion in the fresh group (88.09% vs 52.42%, p < 0.05, 95% CI 11.54, 66.94). There was no significant difference in DNA fragmentations of primordial follicles between each group (p > 0.05).

Conclusions

The vitrification and transplantation process of goat ovarian strips could cause the primordial follicles loss and DNA damage of the follicles. However, primordial follicles loss and DNA damage were not significantly different in each procedure.

Reproductive outcomes after in vitro fertilization treatment in a cohort of Danish women transplanted with cryopreserved ovarian tissue

OBJECTIVE

To evaluate ovarian stimulation regimens and reproductive outcomes in a cohort of women undergoing ovarian tissue cryopreservation (OTC) and ovarian tissue transplantation (OTT).

DESIGN

Retrospective cohort study.

SETTING

University hospital and fertility clinics.

PATIENTS

Twenty-eight women undergoing OTT and in vitro fertilization (IVF) from 2012 to 2017.

INTERVENTION

OTC, OTT, and IVF.

MAIN OUTCOME MEASURES

Ovarian stimulation and IVF outcomes.

RESULTS

In total, 99 cycles were performed in 28 patients. In 19 patients responding to stimulation, a median of 3.0 cycles per patient (range: 1-14 cycles) was performed, and 2.0 mature oocytes were retrieved per cycle. The empty follicle rate was 35.9%. Eleven women achieved 15 pregnancies, of which 60% were lost during the first or second trimester, resulting in 5 of 28 women having ≥1 live births, and seven healthy children being born. In breast cancer patients (mean age at OTC: 33.0 years), the pregnancy rates (PR) and live birth rates (LBR) were 35.0% and 5.0% per embryo transfer, respectively. Patients aged ≥34.5 years at OTC all had breast cancer and did not achieve any pregnancies. For all other diagnoses (mean age at OTC: 26.6 years), PR and LBR were 50.0% and 37.5% per embryo transfer, respectively. Collectively, 39% of patients conceived at least once, and 17.9% delivered. Frozen-thawed embryo transfer (FET) resulted in more pregnancies than did fresh embryo transfer.

CONCLUSION

Our results suggest that women of advanced maternal age undergoing OTC and IVF have a poor ovarian reserve, resulting in a poor reproductive outcome. Interestingly, FET appeared to be superior to fresh transfer.

Quantitative Differences in TGF-β Family Members Measured in Small Antral Follicle Fluids From Women With or Without PCO

CONTEXT

Members of the TGF-β family have been implicated in aberrant follicle development in women with polycystic ovaries (PCO).

OBJECTIVE

Are there quantitative differences in the concentrations of TGF-β family members in fluid from human small antral follicles (hSAFs) in women with or without PCO?

DESIGN AND SETTING

Follicle fluids (FFs) were collected from 4- to 11-mm hSAFs obtained from women undergoing ovarian tissue cryopreservation for fertility preservation.

PATIENTS

FFs from 16 women with PCO (FF = 93) and 33 women without PCO (FF = 92).

MAIN OUTCOME MEASURES

Intrafollicular concentrations of growth differentiation factor-9 (GDF9); anti-Müllerian hormone (AMH); inhibin-A and inhibin-B; total inhibin; activin-A, activin-B, and activin-AB; follistatin; follistatin-like-3; estradiol; and testosterone.

RESULTS

Activin-B concentrations were reported in hSAFs, and concentrations were 10 times higher than activin-A and activin-AB concentrations. Activin-B showed significant associations with other growth factors. Concentrations of inhibin-A and inhibin-B were significantly lower in FFs from women with PCO, especially in hSAFs <8 mm in diameter. AMH concentrations did not differ between the groups in hSAFs <8 mm; however, AMH remained high in hSAFs >8 mm in women with PCO but decreased in women without PCO. Estradiol was significantly lower in FFs from women with PCO and showed significant associations with AMH. Concentrations of GDF9 showed significantly higher concentrations in PCO FFs of follicles >6 mm.

CONCLUSIONS

Altered concentrations of TGF-β family members in hSAFs from women with PCO highlight altered growth factor signaling as a potential mechanism for follicle growth arrest.

FertiPROTEKT, Oncofertility Consortium and the Danish Fertility-Preservation Networks - What Can We Learn From Their Experiences?

Fertility preservation is an increasingly important discipline. It requires close coordination between reproductive medicine specialists, reproductive biologists, and oncologists in various disciplines. In addition, it represents a particular health policy challenge, since fertility-protection measures are to be understood as a treatment for side effects of gonadotoxic treatments and would therefore normally have to be reimbursed by health insurance companies. Therefore, it is inevitable that fertility-preservation activities should organise themselves into a network structure both as a medical-logistic network and as a professional medical society. The necessary network structures can differ significantly at regional, national, and international level, as the size of the regions to be integrated and the local cultural and geographical conditions, as well as the political conditions are very different. To address these issues, the current review aims to point out the basic importance and the chances but also the difficulties of fertility-protection networks and give practical guidance for the development of such network structures. We will not only discuss network structures theoretically but also present them based on three established, different sized networks, such as the Danish Network (www.rigshospitalet.dk), representing a centralised network in a small country; the German-Austrian-Swiss network FertiPROTEKT® (www.fertiprotekt.com), representing a centralised as well as decentralised network in a large country; and the Oncofertility® Consortium (www.oncofertility.northwestern.edu), representing a decentralised, internationally oriented network, primarily serving the transfer of knowledge among its members.

Transcription profile of the insulin-like growth factor signaling pathway during human ovarian follicular development

PURPOSE

The IGF signaling cascade exerts important regulatory functions in human ovarian folliculogenesis. The scope of this study was to evaluate the transcription profile of insulin-like growth factor (IGF) genes during human ovarian follicle development and to analyze follicle fluid levels of key IGF proteins.

METHODS

Gene expression profiling was performed with microarray gene analysis. The analysis was assessed from ovarian follicles and granulosa cells (GCs) obtained from isolated stage-specific human ovarian follicles, including preantral follicles, small antral follicles, and preovulatory follicles. Numerous genes involved in the IGF signaling pathway was evaluated and key genes were validated by qPCR from GCs. Protein levels of various IGF components of human follicular fluid (FF) were measured by ELISA and time-resolved immunofluorometric assays (TRIFMA).

RESULTS

The gene expression levels of PAPPA, IGF2, IGF receptors and intracellular IGF-activated genes increased with increasing follicle size. This was especially prominent in the late preovulatory stage where IGF2 expression peaked. Protein levels of intact IGF binding protein-4 decreased significantly in FF from large preovulatory follicles compared with small antral follicles concomitant with higher protein levels of PAPP-A. The IGF modulators IGF-2 receptor, IGFBPs, stanniocalcins, and IGF-2 mRNA binding proteins were all observed to be expressed in the different follicle stages.

CONCLUSIONS

This study confirms and highlights the importance of PAPP-A regulating bioactive IGF levels throughout folliculogenesis and especially for the high rate of granulosa cell proliferation and expression of key ovarian hormones important in the last part of the follicular phase of the menstrual cycle.

Age-related morphometrical peculiarities of Lithuanian women's primordial ovarian follicles

BACKGROUND

For the first time, thorough morphometrical measurements of primordial ovarian follicles were performed and their age-related changes were investigated in Lithuanian women of the reproductive age.

METHODS

Ovaries of dead women (n = 30) were divided into six age groups: 15-20 years old, 21-25 years old, 26-30 years old, 31-35 years old, 36-40 years old and 41-46 years old. Histological slides of left and right ovaries were stained using haematoxylin-eosin and periodic acid-Schiff (PAS) staining methods. The morphometrical measurements of 10 primordial ovarian follicles of the left and right ovary of each woman were made from microphotographs.

RESULTS

The diameter of primordial ovarian follicles increased in groups of women from 15 years old to 35 years old and decreased in the groups from 36 years old to 46 years old. The area of primordial ovarian follicles increased in the groups of women until 35 years old. It decreased in the groups of women older than 36 years. The follicular basement membrane thickened from 1.29 ± 0.11 μm to 1.43 ± 0.18 μm with increasing age of women. The diameter of primary oocytes enlarged until 35 years and then began to decrease. The area of primary oocytes increased in women until 35 years. It decreased in groups of women aged 36-40 and 41-46 years old. The diameter and the area of primary oocytes nuclei increased in women aged 15-30 years old; later, it began to decrease. The length of follicular cells varied from 8.56 ± 0.43 μm to 8.72 ± 0.27 μm (p > 0.05). The height of follicular cells varied from 2.59 ± 0.27 μm to 2.7 ± 0.21 μm (p > 0.05). The diameter, the area and the basement membrane thickness of primordial ovarian follicles and the diameter and the area of primary oocytes and their nuclei differed insignificantly in left and right ovaries in all age groups of women (p > 0.5). The length and height of follicular cells were similar in left and right ovaries of the same age group (p > 0.5).

CONCLUSIONS

The age decreasing of morphometrical parameters begins in primordial ovarian follicles and their primary oocytes in Lithuanian women older than 35 years. The thickness of the follicular basement membrane increased with increasing age of women. No significant differences were found in the morphometrical parameters in primordial follicles of left and right ovaries in the same age group of women.

Determination of Follicular Localization in Human Ovarian Cortex for Vitrification

PURPOSE

To determine the optimal follicle localization for ovarian vitrification in adolescent and young adult (AYA)-aged (between 15 and 39 years of age) patients with cancer or primary ovarian insufficiency (POI).

METHODS

In total, ovaries from 24 women were included in our study. These include women who received ovariectomy for fertility preservation before gonadotoxic treatments for cancer (n = 4), or for the treatment of POI by the in vitro activation method (n = 8), and other women and infants (0-3 years of age) whose ovaries were autopsied (n = 12). Before cryopreservation, a portion of the ovary sampled from cancer and POI patients was used for histological analysis. Depths of follicles from the surface of ovarian cortices were then measured by using digital imaging software. The locations of the follicles at different developmental stages in the ovarian cortex were noted.

RESULTS

The mean depth at which the primordial and primary follicles were located was 271 μm in infants. This was deeper in women in their twenties, thirties, and forties (501, 462, and 493 μm, respectively). The majority of secondary follicles were located <1000 μm from the ovarian surface (mean depth, 639 μm). In regard to patients with POI, the mean depth of primordial and primary follicles was 566 μm, whereas 70% of secondary follicles were located >1000 μm deep.

CONCLUSION(S)

These findings suggest that <1 mm is a potential optimum thickness of normal ovarian tissue for vitrification and a requirement that thicker ovarian cortices include secondary follicles in POI patients.

Fertility preservation issues in pediatric hematopoietic stem cell transplantation: practical approaches from the consensus of the Pediatric Diseases Working Party of the EBMT and the International BFM Study Group

Fertility preservation is an urgent challenge in the transplant setting. A panel of transplanters and fertility specialists within the Pediatric Diseases Working Party of the European Society for Blood and Marrow Transplantation (EBMT) and the International BFM Study Group provides specific guidelines. Patients and families should be informed of possible gender- and age-specific cryopreservation strategies that should be tailored according to the underlying disease, clinical condition and previous exposure to chemotherapy. Semen collection should be routinely offered to all postpubertal boys at the diagnosis of any disease requiring therapy that could potentially impair fertility. Testicular tissue collection might be offered to postpubertal boys; nevertheless, its use has been unsuccessful to date. Oocyte collection after hormonal hyperstimulation should be offered to postpubertal girls facing gonadotoxic therapies that could be delayed for the 2 weeks required for the procedure. Ovarian tissue collection could be offered to pre-/post-pubertal girls. Pregnancies have been reported after postpubertal ovarian tissue reimplantation; however, to date, no pregnancy has been reported after the reimplantation of prepubertal ovarian tissue or in vitro maturation of pre-/post-pubertal ovarian tissue. Possible future advances in reproductive medicine could change this scenario. Health authorities should prioritize fertility preservation projects in pediatric transplantation to improve patient care and quality of life.

The Protective Effect of N-Acetylcysteine on Ionizing Radiation Induced Ovarian Failure and Loss of Ovarian Reserve in Female Mouse

Ionizing radiation may cause irreversible ovarian failure, which, therefore, calls for an effective radioprotective reagent. The aim of the present study was to evaluate the potential radioprotective effect of N-acetylcysteine (NAC) on ionizing radiation induced ovarian failure and loss of ovarian reserve in mice. Kun-Ming mice were either exposed to X-irradiation (4 Gy), once, and/or treated with NAC (300 mg/kg), once daily for 7 days before X-irradiation. We examined the serum circulating hormone levels and the development of ovarian follicles as well as apoptosis, cell proliferation, and oxidative stress 24 hours after X-irradiation. In addition, morphological observations on the endometrial luminal epithelium and the fertility assessment were performed. We found that NAC successfully restored the ovarian and uterine function, enhanced the embryo implantation, improved the follicle development, and altered the abnormal hormone levels through reducing the oxidative stress and apoptosis level in granulosa cells while promoting the proliferation of granulosa cells. In conclusion, the radioprotective effect of NAC on mice ovary from X-irradiation was assessed, and our results suggested that NAC can be a potential radioprotector which is capable of preventing the ovarian failure occurrence and restoring the ovarian reserve.

Pregnancy after Orthotopic Ovarian Tissue Transplantation Using N-hexyl-2-cyanoacrylate

Cryopreservation of ovarian tissue in advance of cytotoxic therapies and later transplantation of the tissue is being performed increasingly often, and the total success rates in terms of pregnancy and delivery have been described in case series. Most pregnancies were achieved after orthotopic transplantation of tissue (in the peritoneum or the remaining ovary); however, treatment of the transplantation site during surgery is controversial. In this observational case-series study, we include four patients who underwent ovarian tissue transplantation between 2012 and 2016 by laparoscopy. Previously ovarian tissue was cryopreserved with slow freezing protocol prior to chemo- and/or radiotherapy. After cancer remission, the cryopreserved ovarian tissues were orthotopically re-transplanted in the ovarian medulla by laparoscopy, using N-hexyl-2-cyanoacrylate as an absorbable adhesion barrier. All patients regained ovarian function between 8 and 24 weeks after transplantation, as shown by follicle development and estrogen production. In patients 1 and 2 the ovarian function ended one year after transplantation. Patient 3 has regular menstrual cycles 2 years after the transplant and patient 4 currently has an ongoing spontaneous pregnancy.

The use of N-hexyl-2 cyanoacrylate can facilitate the placement of ovarian pieces in orthotopic transplantation by laparoscopy without affecting the restoration and duration of ovarian activity.

Cryopreservation of reproductive material before cancer treatment: a qualitative study of health care professionals' views about ways to enhance clinical care

BACKGROUND

Cancer treatment can diminish fertility in women and men. The need for fertility preservation is growing as increasing numbers of people survive cancer. Cryostorage of reproductive material to preserve potential for conception for cancer survivors has moved from being experimental to being a part of clinical management of women and men who are diagnosed with cancer in their reproductive years. There is little existing evidence about how fertility preservation services can be enhanced to meet the complex needs of patients who are diagnosed with cancer in their reproductive years. The aim of this research was to inform clinical practice development by drawing on the collective experience and knowledge of staff at well-established clinics that offer fertility preservation before cancer treatment.

METHODS

A qualitative research model was adopted using semi-structured interviews with professionals involved in the care of people who freeze reproductive material before cancer treatment. In the state of Victoria, Australia, two large assisted reproductive technology (ART) centres have been providing fertility preservation services for more than two decades. An invitation to participate in a semi-structured interview about clinical care in the context of fertility preservation was emailed to past and current staff members. To capture diverse perspectives, informants were sought from all relevant professions: fertility specialists, andrologists, nurses, embryologists/scientists, counsellors, and administrative staff. Transcripts were analysed thematically.

RESULTS

Thirteen key informants were interviewed from August 2013 to February 2014. The identified themes relating to enhancing clinical care in a fertility preservation service were communication between oncology and ART specialists; managing urgency; managing patients' expectations; establishing and implementing protocols, systems, and data bases; and maintaining contact with patients.

CONCLUSION

The collective knowledge of this study's informants, who represent multidisciplinary teams with more than two decades' experience in fertility preservation, yields important insights into strategies that fertility preservation services can employ to promote the integration of oncology and fertility care, the psychosocial care of patients, data recording and monitoring, and reporting of outcomes.

Highly sensitive assessment of neuroblastoma minimal residual disease in ovarian tissue using RT-qPCR-A strategy for improving the safety of fertility restoration

BACKGROUND

Ovarian tissue cryopreservation (OTC) is the only option available to preserve fertility in prepubertal females with neuroblastoma (NB), a childhood solid tumor that can spread to the ovaries, with a risk of reintroducing malignant cells after an ovarian graft.

PROCEDURE

We set out to determine whether the analysis of TH (tyrosine hydroxylase), PHOX2B (paired-like homeobox 2b), and DCX (doublecortin) transcripts using quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) could be used to detect NB contamination in ovarian tissue. Analyses were performed on benign ovarian tissue from 20 healthy women between November 2014 and September 2015 at the University Hospital of Clermont-Ferrand. Pericystic benign ovarian tissues were collected and contaminated with increasing numbers of human NB cells (cell lines IMR-32 and SK-N-SH) before detection using RT-qPCR.

RESULTS

TH and DCX transcripts were detected in uncontaminated ovarian tissue from all the donors, hampering the detection of small numbers of tumor cells. By contrast, PHOX2B was not detected in any uncontaminated ovarian fragment. PHOX2B levels were significantly increased from 10 NB cells. Our study is the first to evaluate minimal residual disease detection using NB mRNAs in human ovarian tissue. Only PHOX2B was a reliable marker of NB cells contaminating ovarian tissue.

CONCLUSIONS

These results are encouraging and offer hope in the near future for grafting ovarian tissue in women who survive cancer, whose fertility has been jeopardized by treatment, and who could benefit from OTC without oncological risk.

Microfluidic Encapsulation of Ovarian Follicles for 3D Culture

The ovarian follicle that contains one single oocyte is the fundamental functional tissue unit of mammalian ovary. Therefore, isolation and in vitro culture of ovarian follicles to obtain fertilizable oocytes are regarded as a promising strategy for women to combat infertility. In this communication, we performed a brief survey of studies on microfluidic encapsulation of ovarian follicles in core-shell hydrogel microcapsules for biomimetic 3D culture. These studies highlighted that recapitulation of the mechanical heterogeneity of the extracellular matrix in ovary is crucial for in vitro culture to develop early pre-antral follicles to the antral stage, and for the release of cumulus-oocyte complex (COC) from antral follicles in vitro. The hydrogel encapsulation-based biomimetic culture system and the microfluidic technology may be invaluable to facilitate follicle culture as a viable option for restoring women's fertility in the clinic.

ATRX is a novel progesterone-regulated protein and biomarker of low developmental potential in mammalian oocytes

A multi-species meta-analysis of published transcriptomic data from models of oocyte competence identified the chromatin remodelling factor ATRX as a putative biomarker of oocyte competence. The objective of the current study was to test the hypothesis that ATRX protein expression by cumulus-oocyte complexes (COCs) reflects their intrinsic quality and developmental potential. In excess of 10,000 bovine COCs were utilised to test our hypothesis. COCs were in vitro matured (IVM) under conditions associated with reduced developmental potential: IVM in the presence or absence of (1) progesterone synthesis inhibitor (Trilostane); (2) nuclear progesterone receptor inhibitor (Aglepristone) or (3) an inducer of DNA damage (Staurosporine). ATRX protein expression and localisation were determined using immunocytochemistry and Western blot analysis. A proportion of COCs matured in the presence or absence of Trilostane was in vitro fertilised and cultured, and subsequent embryo development characteristics were analysed. In addition, ATRX expression was investigated in 40 human germinal vesicle-stage COCs. Our results showed that ATRX is expressed in human and bovine germinal vesicle oocytes and cumulus cells. In bovine, expression decreases after IVM. However, this decline is not observed in COCs matured under sub-optimal conditions. Blastocyst development rate and cell number are decreased, whereas the incidence of abnormal metaphase phase spindle and chromosome alignment are increased, after IVM in the presence of Trilostane (P < 0.05). In conclusion, localisation of ATRX to the cumulus cell nuclei and oocyte chromatin, after IVM, is associated with poor oocyte quality and low developmental potential. Furthermore, ATRX is dynamically regulated in response to progesterone signalling.

Microscale Biomaterials with Bioinspired Complexity of Early Embryo Development and in the Ovary for Tissue Engineering and Regenerative Medicine

Tissue engineering and regenerative medicine (TERM) are attracting more and more attention for treating various diseases in modern medicine. Various biomaterials including hydrogels and scaffolds have been developed to prepare cells (particularly stem cells) and tissues under 3D conditions for TERM applications. Although these biomaterials are usually homogeneous in early studies, effort has been made recently to generate biomaterials with the spatiotemporal complexities present in the native milieu of the specific cells and tissues under investigation. In this communication, the microfluidic and coaxial electrospray approaches that we used for generating microscale biomaterials with the spatial complexity of both pre-hatching embryos and ovary in the female reproductive system were introduced. This is followed by an overview of our recent work on applying the resultant bioinspired biomaterials for cultivation of normal and cancer stem cells, regeneration of cardiac tissue, and culture of ovarian follicles. The cardiac regeneration studies show the importance of using different biomaterials to engineer stem cells at different stages (i.e., in vitro culture versus in vivo implantation) for tissue regeneration. All the studies demonstrate the merit of accounting for bioinspired complexities in engineering cells and tissues for TERM applications.

Effect of pregnancy-associated plasma protein-A (PAPP-A) single-nucleotide polymorphisms on the level and activity of PAPP-A and the hormone profile in fluid from normal human small antral follicles

OBJECTIVE

To reveal a possible relationship between two single nucleotide polymorphisms (SNPs) in PAPP-A-1224 (rs7020782) and 327 (rs12375498)-and the level and activity of PAPP-A in follicular fluid (FF) of human small antral follicles, and to analyze the intrafollicular hormone levels.

DESIGN

Laboratory investigation.

SETTING

University hospital.

PATIENT(S)

Fifty volunteer women who contributed a total of 210 samples of FF from normal small antral follicles.

INTERVENTION(S)

Genotyping and measurement of antigen levels of steroids, PAPP-A, stanniocalcin-2 (STC2), and antimüllerian hormone (AMH) plus activity of PAPP-A toward insulin-like growth factor binding protein 4 (IGFBP-4).

MAIN OUTCOME MEASURE(S)

Measurement of PAPP-A levels and hormones with enzyme-linked immunosorbent assay (ELISA) and PAPP-A activity toward radiolabeled IGFBP-4.

RESULT(S)

Women homozygous for the minor C allele of the 1224 SNP showed a statistically significantly lower level of PAPP-A protein and activity in FF compared with women carrying the major A allele. These women also displayed nonsignificant reduced levels of estradiol and increased levels of AMH and androgen. A statistically significant correlation between FF levels of PAPP-A activity and the molar ratio of PAPP-A/STC2 was obtained. The 327 SNP did not show statistically significant associations.

CONCLUSION(S)

This study presents a statistically significant effect of the 1224 SNP on the level and activity of PAPP-A in human follicles, suggesting that the FF level of bioactive insulin-like growth factor depends on the genotype. We observed STC2 to be an important regulator of PAPP-A in human FF. The 1224 SNP has previously been associated with recurrent pregnancy loss, so further evaluation of an underlying mechanism including aberrant control of insulin-like growth factor activity is warranted.

In vitro culture of ovarian follicles from Peromyscus

The ovarian follicle is the fundamental functional tissue unit of mammalian ovary. Each ovarian follicle contains one single oocyte. Isolation and in vitro culture of ovarian follicles to obtain fertilizable oocytes have been regarded as a promising strategy for women to combat infertility. The follicles from Peromyscus are considered as a better model than that from inbred mice for studying follicle culture. This is because Peromyscus mice are outbred (as with humans) with an increased life span. In this article, we reviewed studies on this subject conducted using Peromyscus follicles. These studies show that the conventional 2D micro-drop and 3D hanging-drop approaches established for in vitro culture of early preantral follicles from inbred mice are not directly applicable for cultivating the follicles from Peromyscus. However, the efficiency could be significantly improved by culturing multiple early preantral follicles in one hanging drop of Peromyscus ovarian cell-conditioned medium. It is further revealed that the mechanical heterogeneity in the extracellular matrix of ovary is crucial for developing early preantral follicles to the antral stage and for the subsequent ovulation to release cumulus-oocyte complex. These findings may provide valuable guidance for furthering the technology of in vitro follicle culture to restore fertility in the clinic.

The proteolytic activity of pregnancy-associated plasma protein-A is potentially regulated by stanniocalcin-1 and -2 during human ovarian follicle development

STUDY QUESTION

Is the proteolytic activity of pregnancy-associated plasma protein-A (PAPP-A) regulated by the stanniocalcins (STC1 and STC2) during human follicle maturation?

SUMMARY ANSWER

The STCs and PAPP-A show similar expression by immunohistochemistry in developing follicles, and regulation of PAPP-A proteolytic activity is suggested by the identification of inhibited protein complexes between PAPP-A and STC1 or STC2 in human follicular fluid (FF).

WHAT IS KNOWN ALREADY

The insulin-like growth factor (IGF)-regulating proteinase PAPP-A is secreted by the granulosa cells of estrogen-dominant follicles and is involved in follicle growth. STC1 and STC2 have recently been identified as novel PAPP-A inhibitors, and their expression in non-human mammalian ovaries has previously been observed.

STUDY DESIGN, SIZE, DURATION

The proteolytic activity of PAPP-A in human follicular fluid was assessed, and the interaction between PAPP-A and the STCs in human ovarian tissues and follicular fluid was analyzed using immunoassays. From 21 women, matched pairs of follicular fluid were obtained from one follicle just prior to final maturation of follicles with human chorionic gonadotrophin (hCG), and from another follicle in connection with oocyte aspiration after hCG treatment. Ovarian tissues were obtained from women having one ovary removed for fertility preservation by cryopreservation prior to gonadotoxic treatment.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The concentration and activity of PAPP-A were determined in all samples of follicular fluid. Furthermore, to investigate PAPP-A regulation during follicle development, immunohistochemical staining of PAPP-A, STC1, and STC2 was performed on pre-antral and antral human follicles. To attempt the demonstration of native complexes between PAPP-A and the STCs, immunoprecipitation from a pool of human follicular fluid was performed.

MAIN RESULTS AND THE ROLE OF CHANCE

The concentration of PAPP-A antigen in follicular fluid increased upon stimulation of ovulation with hCG (P < 0.02), but at the same time, PAPP-A activity was decreased. PAPP-A, STC1, and STC2 were localized together in primordial, late primary, and antral follicles, indicating that complex formation is possible in ovarian tissue. Covalent PAPP-A:STC2 and non-covalent PAPP-A:STC1 complexes were immunoprecipitated from follicular fluid, documenting for the first time native inhibited complexes between PAPP-A and the STCs.

LIMITATIONS, REASONS FOR CAUTION

We have demonstrated the presence of native complexes between PAPP-A and the STCs in the human ovary, indicating STC-mediated PAPP-A proteolytic inhibition. Further investigation is required to extend this principle to other tissues.

WIDER IMPLICATIONS OF THE FINDINGS

Our data suggest that the STCs contribute to PAPP-A regulation during folliculogenesis and support a general model in which STC1 and STC2 are regulators of mammalian IGF activity through inhibition of PAPP-A. We suggest that future functional studies take both PAPP-A and the STCs into consideration.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by grants from the Novo Nordisk Foundation, and the Danish Council for Independent Research. No competing interests declared.

Outcomes of transplantations of cryopreserved ovarian tissue to 41 women in Denmark

STUDY QUESTION

What are the results of transplanting cryopreserved ovarian tissue?

SUMMARY ANSWER

The transplanted ovarian tissue can last up to 10 years, with no relapses following the 53 transplantations, and the chance of a successful pregnancy is currently around one in three for those with a pregnancy-wish.

WHAT IS KNOWN ALREADY

Cryopreservation of ovarian tissue is now gaining ground as a valid method for fertility preservation. More than 36 children worldwide have now been born following this procedure.

STUDY DESIGN, SIZE, DURATION

This is a retrospective cohort study of 41 women who had thawed ovarian tissue transplanted 53 times over a period of 10 years, including 1 patient who was lost to follow-up.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The 41 Danish women, who had in total 53 transplantations, were followed for ovarian function and fertility outcome. Safety was assessed by monitoring relapse in cancer survivors.

MAIN RESULTS, AND THE ROLE OF CHANCE

Among 32 women with a pregnancy-wish, 10 (31%) had a child/children (14 children in total); this included 1 woman with a third trimester on-going pregnancy. In addition, two legal abortions and one second trimester miscarriage occurred. A total of 24 clinical pregnancies were established in the 32 women with a pregnancy-wish. The tissue remained functional for close to 10 years in some cases and lasted only a short period in others. Three relapses occurred but were unlikely to be due to the transplanted tissue.

LIMITATIONS, REASONS FOR CAUTION

Self-report through questionnaires with only in-one hospital formalised follow-up of transplanted patients could result in unreported miscarriages. The longevity of the tissue may vary by few months compared with those reported because some patients simply could not remember the date when the tissue became non-functional.

WIDER IMPLICATIONS OF THE FINDINGS

Cryopreservation of ovarian tissue is likely to become integrated into the treatment of young women, with cancer, who run a risk of losing their fertility. The full functional lifespan of grafts is still being evaluated, because many of the transplanted women have continued to maintain ovarian activity. Some of our first cases have had tissue functioning for ∼ 10 years.

[Does the serum AMH assay allow predicting reliably female fertility?]

In women, the anti-Müllerian hormone (AMH) is secreted by the granulosa cells of growing follicles. Its measurement is strongly correlated with antral follicle count and represents a reliable marker of ovarian reserve. It also has the advantage of being highly reproducible since it has little variation within and between cycles. However, although it seems to be a good quantitative reflection of the ovarian reserve, it does not assess the oocyte quality. This drawback precludes any good prediction of female fertility in the general population. However, the AMH assay can become an indirect marker of female fertility in some situations at risk for premature ovarian failure or in the polycystic ovary syndrome. Its interest is no more to be proven in assisted reproductive technology where it is a valuable aid to the choice of the proposed techniques, ovarian stimulation protocols and gonadotropin doses. AMH is finally very informative in monitoring cancer patients having received ovariotoxic drugs or having undergone mutilating ovarian surgeries. In conclusion, although it cannot be considered itself as a reliable predictor of pregnancy in women, AMH is now a must in the management and treatment of female infertility.

Successful fertility preservation following ovarian tissue vitrification in patients with primary ovarian insufficiency

STUDY QUESTION

Is ovarian tissue cryopreservation using vitrification followed by in vitro activation (IVA) of dormant follicles a potential approach for infertility treatment of patients with primary ovarian insufficiency (POI)?

SUMMARY ANSWER

Our vitrification approach followed by IVA treatment is a potential infertility therapy for POI patients whose ovaries contain residual follicles.

WHAT IS KNOWN ALREADY

Akt (protein kinase B) stimulators [PTEN (phosphatase with TENsin homology deleted in chromosome 10) inhibitor and phosphatidyinositol-3-kinase (PI3 kinase) stimulator] activate dormant primordial follicles in vitro and ovarian fragmentation disrupts the Hippo signaling pathway, leading to the promotion of follicle growth. We treated POI patients with a combination of ovarian vitrification, fragmentation and drug treatment, followed by auto-transplantation, and reported successful follicle growth and pregnancies.

STUDY DESIGN, SIZE, DURATION

Prospective clinical study of 37 infertile women with POI between 12 August 2011 and 1 November 2013. We enrolled 10 new patients since the previous publication.

PARTICIPANTS/MATERIALS, SETTING, METHODS

POI patients were originally selected based on a history of amenorrhea for more than 1 year and elevated serum FSH levels of >40 mIU/ml (n = 31) but this was later changed to >4 months, age <40 years and serum FSH levels of >35 mIU/ml (n = 6) (mean 71.8 ± 30.8, range 35.5-197.6) so as to include patients with a shorter duration of amenorrhea. Under laparoscopic surgery, ovariectomy was performed and ovarian cortices were dissected into strips for vitrification. Some pieces were examined histologically. After warming, two to three strips were fragmented into smaller cubes before culturing with Akt stimulators for 2 days. After washing, ovarian cubes were transplanted beneath the serosa of Fallopian tubes under laparoscopic surgery. Follicle growth was monitored by ultrasound and serum estrogen levels. After oocyte retrieval from mature follicles, IVF was performed.

MAIN RESULTS AND THE ROLE OF CHANCE

Among 37 patients, 54% had residual follicles based on histology. Among patients with follicles, 9 out of 20 showed follicle growth in auto-grafts with 24 oocytes retrieved from six patients. Following IVF and embryo transfer into four patients, three pregnancies were detected based on serum hCG, followed by one miscarriage and two successful deliveries. For predicting IVA success, we found that routine histological analyses of ovarian cortices and shorter duration from initial POI diagnosis to ovariectomy are valid parameters.

LIMITATIONS, REASONS FOR CAUTION

Although our findings suggest that the present vitrification protocol is effective for ovarian tissue cryopreservation, we have not compared the potential of vitrification and slow freezing in follicle growth after grafting. We chose the serosa of Fallopian tubes as the auto-grating site due to its high vascularity and the ease to monitor follicle growth. Future studies are needed to evaluate the best auto-grafting sites for ovarian tissues. Also, future studies are needed to identify biological markers to indicate the presence of residual follicles in POI to predict IVA treatment outcome.

WIDER IMPLICATIONS OF THE FINDINGS

In POI patients, ovarian reserve, namely the pool of residual follicles, continues to diminish with age. If one ovary is cryopreserved at an earlier stage of POI, patients could undergo additional non-invasive infertility treatments before the final decision for the IVA treatment. Furthermore, in the cases of unmarried POI patients, cryopreservation of ovarian tissues allows their fertility preservation until they desire to bear children.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by Grant-In-Aid for Scientific Research (Research B: 24390376, Challenging Exploratory Research: 24659722, and Innovative Areas, Mechanisms regulating gamete formation in animals: 26114510) and by research funds from the Smoking Research Foundation, and the Takeda Science Foundation. None of the authors has a conflict of interest.

TRIAL REGISTRATION NUMBER

UMIN000010828.

Safety considerations for transplanting cryopreserved ovarian tissue to restore fertility in female patients who have recovered from Ewing’s sarcoma

ABSTRACT Ewing’s sarcoma (EWS) is a highly malignant cancer in children, adolescents and young adults. The chemotherapy required to treat female EWS patients may cause primary ovarian insufficiency and infertility as a side effect. Cryopreservation of ovarian tissue before the start of chemotherapy can potentially preserve fertility. When the patient has been cured and primary ovarian insufficiency has developed, transplantation of frozen/thawed ovarian tissue can restore ovarian function. The tissue is usually collected before chemotherapy is initiated, and malignant cells may contaminate the stored ovarian tissue, potentially causing recrudescence of the original cancer after transplantation. The risk of EWS metastasizing to the ovary is probably low but has not been studied in great detail. This review describes the available evidence on the risk of malignant cell contamination in the ovaries of EWS patients and presents a new case of malignant cells in an ovarian biopsy from a girl with EWS.

Developmental competence of oocytes isolated from surplus medulla tissue in connection with cryopreservation of ovarian tissue for fertility preservation

OBJECTIVE

Evaluating the developmental competence of immature oocytes collected from surplus medulla tissue in connection with ovarian tissue cryopreservation for fertility preservation.

DESIGN

Cohort comparative study.

SETTING

University laboratory in Denmark from 2011-2012.

POPULATION

69 girls and women (0-38 years of age) who each had one ovary cryopreserved for fertility preservation.

METHODS

Ovaries were obtained directly from the local hospital or from collaborating hospitals (two to five hours' transport on ice). Immature oocytes were aspirated from large antral follicles visible on the ovaries, and collected from the saline solution, containing surplus medulla tissue, following dissection of the ovarian cortical tissue for cryopreservation. The immature oocytes were cultured for 48 h in an Embryoscope™ Time-lapse System or in culture dishes overlaid with liquid paraffin using commercial and in-house supplemented culture media.

MAIN OUTCOME MEASURES

Maturation rate for immature oocytes reaching metaphase II.

RESULTS

With a maturation rate of 3.1%, only 21 of 682 immature oocytes reached metaphase II. Immature oocytes from ovaries that had been transported on ice for two to five hours performed significantly poorer than those recovered immediately after surgery. Addition of epidermal growth factor and follicle fluid from human small antral follicles to the culture medium did not augment the maturation rate. Immature oocytes cultured in the Embryoscope performed significantly better than those in conventional culture dishes.

CONCLUSIONS

In vitro maturation of immature oocytes should only be attempted clinically from visible antral follicles and where the ovary is not subjected to a cooling period prior to recovery of immature oocytes.

From the bench to bedside to babies: translational medicine made possible by funding multidisciplinary team science

PURPOSE

In 2005, The National Institutes of Health (NIH) called upon the scientific community to identify the most intractable problems in science and medicine and describe how we would solve these problems using teams.

METHODS

Our group was one of 8 research communities awarded an 'interdisciplinary research consortium (IRC) grant.' Using the infrastructure of this large, multi-institute grant and a team science approach, we set out to solve the problem of fertility loss in young female cancer patients-work that was not easily funded through other mechanisms.

RESULTS

The word 'oncofertility' was coined specifically for the IRC to reflect the intimate partnership between oncology care and fertility care for these patients-two disciplines that would no longer function at arms' length, but as an integrated unit. Catalyzed by the IRC funding mechanism, interdisciplinary teams worked together in unique ways to create a 'bench to bedside to baby' outcome.

CONCLUSIONS

The grant has now ended, and remarkably, so have the most intractable parts of the original problem. As we look back on what worked and look forward to tackling the next set of fertility-related questions, we are confident that this very special NIH funding mechanism made a meaningful difference in the lives of women and their future children. NIH and the public would be well-served by supporting clinical problem-based, multidisciplinary team science approaches to catalyze fundamental biomedical breakthroughs and create new intellectual environments in which changes in clinical practice and standard of care can be implemented.

In vitro culture of early secondary preantral follicles in hanging drop of ovarian cell-conditioned medium to obtain MII oocytes from outbred deer mice

The ovarian follicle (each contains a single oocyte) is the fundamental functional tissue unit of mammalian ovaries. In humans, it has been long held true that females are born with a maximum number of follicles (or oocytes) that are not only nonrenewable, but also undergoing degeneration with time with a sharply decreased oocyte quality after the age of ∼35. Therefore, it is of importance to isolate and bank ovarian follicles for in vitro culture to obtain fertilizable oocytes later, to preserve the fertility of professional women who may want to delay childbearing, young and unmarried women who may lose gonadal function because of exposure to environmental/occupational hazards or aggressive medical treatments, such as radiation and chemotherapy, and even endangered species and breeds. Although they contributed significantly to the understanding of follicle science and biology, most studies reported to date on this topic were done using the man-made, unnatural inbred animal species. It was found in this study that the conventional two-dimensional microliter drop and three-dimensional hanging drop (HD) methods, reported to be effective for in vitro culture of preantral follicles from inbred mice, are not directly transferrable to outbred deer mice. Therefore, a modified HD method was developed in this study to achieve a much higher (>5 times compared to the best conventional methods) percentage of developing early secondary preantral follicles from the outbred mice to the antral stage, for which, the use of an ovarian cell-conditioned medium and multiple follicles per HD were identified to be crucial. It was further found that the method for in vitro maturation of oocytes in antral follicles obtained by in vitro culture of preantral follicles could be very different from that for oocytes in antral follicles obtained by hormone stimulation in vivo. Therefore, this study should provide important guidance for establishing effective protocols of in vitro follicle culture to preserve the fertility of wildlife and humans outbred by nature.

Legal termination of a pregnancy resulting from transplanted cryopreserved ovarian tissue due to cancer recurrence

PURPOSE

To report on a woman who conceived naturally and had a normal intrauterine pregnancy following transplantation of frozen/thawed ovarian tissue but decided to have an early abortion due to recurrence of breast cancer.

METHODS

The patient was diagnosed breast cancer and received antineoplastic treatment that forced her into premature ovarian insufficiency and infertility. Ovarian tissue cryopreserved prior to chemotherapy was transplanted following cancer treatment restoring fertility and regular menstrual cycles.

RESULTS

The patient conceived 6 month after transplantation. However, she experienced recurrence of breast cancer and decided on legal termination of the pregnancy in the first trimester.

DISCUSSION

The obtained pregnancy only 6 month following transplantation underlines the ability of the procedure. The recurrence occurred near the original site of the tumor and was most unlikely related to the transplantation. The activity of the transplanted tissue is likely to be destroyed by the renewed antineoplastic treatment she will receive. However, she still has the majority of one ovary cryostored and may later want to undergo additional transplantation to regain fertility or to have menstrual cycles back.

Ovarian follicle culture: advances and challenges for human and nonhuman primates

The removal and cryostorage of ovarian cortical biopsies is now offered as a fertility preservation option for young women. The only available option to restore fertility using this tissue is by transplantation, which may not be possible for all patients. The full potential of this tissue to restore fertility could be achieved by the development of in vitro systems that support oocyte development from the most immature stages to maturation. The techniques of in vitro growth (IVG) combined with in vitro maturation (IVM) are being developed with human tissue, but comparing different systems has been difficult because of the scarcity of tissue so nonhuman primates are being used as model systems. There are many challenges to developing a complete culture system that would support human oocyte development, and this review outlines the approaches being taken by several groups using tissue from women and nonhuman primate models to support each of the stages of oocyte development.

Curative resection of hilar cholangiocarcinoma in a 25-year-old woman: report of a case

A 25-year-old woman was referred to our hospital with persistent upper abdominal pain. Preoperative imaging studies revealed a hilar bile duct stricture with portal venous encasement, and the patient underwent curative resection involving extended left hepatectomy and segmental portal vein resection. The pathological findings demonstrated a well-differentiated tubular adenocarcinoma of the bile duct with regional lymph node metastasis (stage IIIB according to the UICC TNM classification), as well as the overexpression of p53 proteins and the K-ras gene mutation in tumor cells. The patient has shown no evidence of recurrence in the 10 months since the operation. Although there are several reports of relatively young adults with cholangiocarcinoma, the majority of such patients demonstrate either an anomalous arrangement of the pancreaticobiliary duct system or primary sclerosing cholangitis. The absence of any morphological abnormalities in this patient's biliary system implicates de novo carcinogenesis as the most likely cause of the cholangiocarcinoma.

Short-term culture of ovarian cortex pieces to assess the cryopreservation outcome in wild felids for genome conservation

Background

Cryopreservation of ovarian tissue has the potential to preserve female germ cells of endangered mammals. In the present study, a freezing protocol successfully used for human tissue, was adapted for preserving ovarian tissue of domestic and non-domestic felids. Ovaries from non-domestic felid species were obtained from seven freshly euthanized and two recently deceased wild felids kept in different European Zoos. In addition, ovaries from domestic cats were obtained after ovariectomy from local veterinary clinics for methological adaptations.

Ovarian cortex was dissected and uniform sized pieces of 2 mm diameter were obtained. Using a slow freezing protocol (-0.3°C per min) in 1.5 mol/L ethylene glycol, 0.1 mol/L sucrose, the pieces were cultured for up to 14 days both before and after cryopreservation. The integrity of primordial follicles was assessed by histology, and the impact of different protein sources (FCS or BSA) and Vitamin C was determined during two weeks of culture.

Results and conclusion

During culture the number of primordial follicles decreased within the ovarian pieces (p < 0.05). This effect was less pronounced when FCS was used as the protein source instead of BSA. Supplementation with Vitamin C had a detrimental effect on follicle survival. Since the procedure of cryopreservation had no effect on the follicle survival after one week of culture we conclude that the freezing protocol was suitable for felids. This is the first report of preserving a huge amount of follicles within ovarian tissue by slow freezing performed in several wild feline species.

Sodium selenite improves folliculogenesis in radiation-induced ovarian failure: a mechanistic approach

Radiotherapy is a major factor contributing to female infertility by inducing premature ovarian failure (POF). Therefore, the need for an effective radioprotective agent is evident. The present study investigated the mechanism of potential radioprotective effect of sodium selenite on radiation-induced ovarian failure and whether sodium selenite can stimulate in-vivo follicular development in experimental rats. Immature female Sprague-Dawely rats were either exposed to gamma-radiation (3.2 Gy, LD₂₀), once and/or treated with sodium selenite (0.5 mg/kg), once daily for one week before irradiation. Follicular and oocyte development, apoptotic markers, proliferation marker as well as oxidative stress markers were assessed 24-h after irradiation. In addition, fertility assessment was performed after female rats became completely mature at two months of age. Sodium selenite significantly enhanced follicular development as compared to the irradiated group. Sodium selenite significantly reversed the oxidative stress effects of radiation that was evidenced by increasing in lipid peroxide level and decreasing in glutathione level, and glutathione peroxidase (GPx) activity. Assessment of apoptosis and cell proliferation markers revealed that caspase 3 and cytochrome c expressions markedly-increased, whereas, PCNA expression markedly-decreased in the irradiated group; in contrast, sodium selenite treatment prevented these alterations. Histopathological examination further confirmed the radioprotective efficacy of sodium selenite and its in-vivo effect on ovarian follicles’ maturation. In conclusion, sodium selenite showed a radioprotective effect and improved folliculogenesis through increasing ovarian granulosa cells proliferation, estradiol and FSH secretion, and GPx activity, whilst decreasing lipid peroxidation and oxidative stress, leading to inhibition of the apoptosis pathway through decreasing the expressions of caspase 3 and cytochrome c.

Case report: stimulation of puberty in a girl with chemo- and radiation therapy induced ovarian failure by transplantation of a small part of her frozen/thawed ovarian tissue

AIM OF THE STUDY

To induce puberty by transplantation of frozen/thawed ovarian tissue collected prior to gonadotoxic treatment for a cancer.

PATIENTS AND METHODS

A 9-year-old girl with Ewing sarcoma had one ovary excised and cryopreserved prior to chemo- and radiotherapy. Functional activity of the remaining ovary was destroyed during treatment. Four and a half years later the girl remained pre-pubertal with postmenopausal levels of FSH. Two of ten pieces of frozen/thawed cortex were transplanted to the remaining ovary in order to stimulate puberty.

RESULTS

Four months after the transplantation FSH returned to low levels. During the following year puberty gradually progressed to Tanner stage B4 and P3 and regular menstrual cycles started. However, after 19 months the function of the graft ceased.

CONCLUSIONS

We have shown for the first time in a girl treated for cancer that transplanted ovarian tissue can regain function and secrete estradiol in a sufficient amount to induce puberty. In addition, the majority of her ovarian tissue remains frozen with a possibility to support fertility in adult life.