Cryopreservation of complex structures comprised from different cell types (bovine cumulus-oocyte-complexes and rat pancreatic islets)

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K07985
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Animal production science
• Research Institution: Shinshu University
• Principal Investigator: Hochi Shinichi 信州大学, 学術研究院繊維学系, 教授 (10283243)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: ガラス化保存 / 卵丘卵子複合体 / 膵島 / クライオトップ / ナイロンメッシュ / シルクフィブロイン

Outline of Final Research Achievements

The aim of this study was to establish the cryopreservation protocols suitable for tissue complexes composed of multiple cell types, such as bovine cumulus-oocyte complexes and rat pancreatic islets. Results obtained were: (1) Downsizing cumulus layers in germinal vesicle-stage bovine cumulus-oocyte complexes contributed to the higher revivability of the oocytes after Cryotop vitrification. (2) Large amounts of metaphase-II stage bovine oocytes were able to survive vitrification on a novel cryodevice, nylon mesh triangle. (3) Cryotop vitrification protocol was superior to conventional Bicell freezing regimen in cryopreservation of rat pancreatic islets, when their revivability was evaluated by glucose-stimulated insulin secretion ability in vitro. The nylon mesh triangle device was also applicable to a large amount of pancreatic islets. (4) Type-1 diabetes model rats were rescued from hyperglycemia by syngeneic transplantation of post-warm islets beneath the kidney capsule.

Free Research Field

動物生産科学

Academic Significance and Societal Importance of the Research Achievements

耐凍性が極めて低いウシ未受精卵子の超低温保存に挑戦し、世界最高水準のガラス化蘇生率を達成するに至った道のりは、ヒトの不妊治療現場で問題となっている加齢等で低品質になった卵子を保存可能にするためにも有用な情報となる。卵子とはまったく異なる異種細胞構造体である膵島にガラス化保存研究を展開し、ラットを用いた糖尿病治療モデルを提唱するに至った。膵島移植というインスリン依存性１型糖尿病の根治療法を普及させるために慢性的障害となっているドナー不足の克服に貢献するもので、移植膵島に高頻度で起こる免疫拒絶の回避に挑戦する足場を築くことができた。