title: Synthetic polymers improve vitrification outcomes of macaque ovarian tissue as assessed by histological integrity and the in vitro development of secondary follicles.
abstract: Ovarian tissue cryopreservation is the only proven option for fertility preservation in female cancer patients who are prepubertal or require immediate treatment. However it remains unclear which cryopreservation protocol is best in cases where the tissue may contain cancerous cells, as these should be matured in vitro rather than autografted. This study evaluated different cryoprotectant exposure times and whether the addition of synthetic polymers (Supercool X-1000, Z-1000 and polyvinylpyrrolidone [PVP K-12]) to the vitrification solution is beneficial to tissue morphology, cellular proliferation and subsequent in vitro function of secondary follicles. Pieces of macaque (n=4) ovarian cortex were exposed to vitrification solution containing glycerol (25%, v/v) and ethylene glycol (25%, v/v) for 3 or 8 min, without (V3, V8) or with (VP3, VP8) polymers (0.2% [v/v] X-1000, 0.4% Z-1000 and 0.2% PVP). Fresh and vitrified tissues were fixed for histology and phosphohistone H3 (PPH3) analysis, or used for secondary follicle isolation followed by encapsulated 3D culture. Five-week follicle survival and growth, as well as steroid hormones (estradiol [E(2)], progesterone, androstenedione) were measured weekly. Morphology of the stroma and preantral follicles as well as PPH3 expression, was preserved in all vitrified tissues. Vitrification with polymers and shorter incubation time (VP3) increased in vitro follicle survival and E(2) production compared to other vitrified groups. Thus, a short exposure of macaque ovarian tissue to a vitrification solution containing synthetic polymers preserves morphology and improves in vitro function of secondary follicles.
authors.affiliation: Division of Reproductive Sciences, Oregon National Primate Research Center, Beaverton, OR 97006, USA.
authors.forename: Alison Y
authors.initials: AY
authors.lastname: Ting
authors.forename: Richard R
authors.initials: RR
authors.lastname: Yeoman
authors.forename: Maralee S
authors.initials: MS
authors.lastname: Lawson
authors.forename: Mary B
authors.initials: MB
authors.lastname: Zelinski
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000494:pharmacology*; D005260:Female; D059247:Fertility Preservation / Q000379:methods; D012739:Gonadal Steroid Hormones / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D008253:Macaca mulatta / Q000378:metabolism; D009865:Oocytes / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D006080:Ovarian Follicle / Q000187:drug effects / Q000254:growth & development*; D010053:Ovary / Q000187:drug effects / Q000254:growth & development*; D011108:Polymers / Q000494:pharmacology*; D013997:Time Factors; D058989:Vitrification
chemical_list: D003451:Cryoprotective Agents; D012739:Gonadal Steroid Hormones; D006657:Histones; D011108:Polymers