Einfrieren von Gonadengewebe zur Erhaltung der Fruchtbarkeit bei Personen mit einem Risiko für Ovarialfunktionsstörung und vorzeitige Ovarialinsuffizienz

Study Description:

Gonadal tissue cryopreservation will be evaluated in individuals with Turner Syndrome, galactosemia, post-menarcheal adolescents with recent premature ovarian insufficiency, and children/adolescents conditions associated with POI and with diminished ovarian reserve (DOR) who have contraindication to ovarian stimulation as well as those with diminished ovarian reserve who did not respond to ovarian stimulation, and individuals with variations in sex characteristics (VSD or differences in sex development, DSD) including those with Turner syndrome with Y chromosome material and those with conditions that require high risk gonadotoxic therapy.

Objectives:

Primary Objectives: After initial evaluation of number and quality of follicles/gametes, the remaining tissue will be utilized to perform research regarding mechanisms of follicle/gametes loss in the included conditions.

a. We will perform next generation sequencing on the tissue collected from study participants and ovaries from cadaveric organ donors on cardiopulmonary support. Additionally, some ovarian tissue from patients undergoing gonadotoxic therapy will function as controls.

Hypothesis: next generation sequencing from tissue obtained from gonads in individuals with these conditions will differ significantly from that of controls. Such differences may allow for further hypothesis development regarding the underlying mechanism of follicle loss and/or dysfunction in individuals with these conditions.

Secondary Objective: This protocol is designed to evaluate the feasibility (meaning a reasonable expectation of future fertility based on the anatomy, histology, and physiology of fresh gonadal tissue as well as the effects after freezing and thawing) of gonadal tissue cryopreservation (GTC) for fertility preservation in children with increased risk of loss of gonadal function due to underlying genetic conditions including Turner syndrome or galactosemia and post-menarcheal adolescents with a recent development of premature ovarian insufficiency (POI) or children/adolescents with conditions associated with POI and presenting with diminished ovarian reserve (based on laboratory findings of low AMH (<1.0 ng/mL) and/or mildly elevated FSH (>10 U/L) or those who do not respond to ovarian stimulation for oocyte cryopreservation due to lower follicle counts) or individuals with variations in sex characteristics.

1. The feasibility GTC as a fertility preservation option in these individuals will be evaluated through evaluation of number and quality of follicles/gametes found in the tissue prior to freezing and after thawing.
2. Lack of follicles/gametes in the gonadal tissue will confirm that GTC is not a viable option for fertility preservation for these populations.
3. An attempt to correlate laboratory and imaging markers with follicle/gamete presence and number will be made.

b. Hypothesis: Young individuals with Turner syndrome, variations of sex characteristics, classic galactosemia and adolescents with recent POI, and children/adolescents with underlying conditions associated with POI presenting with DOR harbor populations of follicles/gametes which may be preserved through gonadal tissue cryopreservation for future fertility. There will be a variety of follicular findings which will correlate with patient s anti-Mullerian hormone (AMH), age and underlying condition.

c. Depending on their underlying condition, individuals with VSC will have gametes (follicles and/or spermatogonia).

d. Loss of follicles with cryopreservation and thawing will be similar to that of non-affected individuals.

Tertiary Objectives:

Research regarding inhibition and activation of follicles within the tissue will be undertaken.

1. Tissue will be treated with known inhibitors and activators and next generation sequencing will be performed in order to assess gene expression before and after treatment.
2. To create a national database of human ovarian tissue of individuals who are undergoing OTC in order to elucidate short and long term outcomes including complication and reproductive health parameters.

Hypothesis: Primordial follicles within gonadal tissue in individuals with these conditions may be inhibited from activating. Such techniques may allow for a decrease in follicle loss with freezing and thawing as well as possible future development of novel treatments to prevent accelerated follicle loss in individuals and adolescent affected by these conditions. Promoting follicle activation prior to re-implantation of the tissue may improve the possibility of achieving pregnancy after tissue re-implantation

Endpoints:

Primary Endpoints:

1. Tissue for research: Next generation sequencing will be performed on tissues of affected individuals and compared to age matched controls: patients who undergo GTC for solid organ tumors far from the reproductive system or cadaveric organ donors on cardiopulmonary support. This will allow for specific cellular type comparisons within the ovary and exploratory research regarding possible mechanisms of follicle loss in these populations.
2. Next generation sequencing on fresh compared to frozen and thawed tissue. This will assess what transcription changed occur due to the freezing process.

Secondary Endpoint:

1. Evaluation of density and quality of follicles/gametes in the gonads of individuals with increased risk of loss of gonadal function due to underlying genetic conditions including Turner syndrome or galactosemia and post-menarcheal adolescents with a recent development of premature ovarian insufficiency (POI) or children/adolescents with conditions associated with POI and presenting with diminished ovarian reserve (based on laboratory findings of low AMH (<1.1 ng/mL) and mildly elevated FSH (10-25 U/L) or those who do not respond to ovarian stimulation for oocyte cryopreservation due to lower follicle counts) or individuals with variations in sex characteristics.
2. Correlation of follicle/gamete density and quality with markers such as age, AMH, condition.
3. Comparison of hormone levels such as AMH, FSH, LH, and Estradiol between patients and controls.
4. Long term data regarding surgical complications

Tertiary Endpoint:

-Evaluate changes in single next generation sequencing in tissue before and after treatment with primordial follicle inhibitors and activators. The remaining tissue will be cryopreserved for future experiments.