Mavrides Andreas, Morroll David
Department of Human Development, University of Nottingham, Queen's Medical Centre, UK.
Reprod Nutr Dev. 2002 Jan-Feb;42(1):73-80. doi: 10.1051/rnd:20020008.
The cryoloop is a technique where a thin nylon loop is used to suspend a film of cryoprotectant containing the oocytes and directly immersing them in liquid nitrogen. 508 bovine oocytes were collected, of these 351 were cryopreserved by slow freezing using standard straws or a new vitrification method using our self-constructed cryoloops and the remainder were controls. After thawing, the oocytes were inseminated by ICSI or standard IVF. The cryoloop vitrification method yielded a survival rate of 90.5% and the slow freezing technique a rate of 54.4% (p < 0.0001). When ICSI was performed, cryopreservation by the cryoloop vitrification method resulted in very similar cleavage rate to controls (16.0% vs. 17.3%) but slow freezing produced a slightly lower rate (9.4%). Cleavage rates after IVF in fresh oocytes was higher than the cryopreservation groups (49.5% vs. 15.4% and 25.8%), whereas after ICSI the rates were similar in all groups (17.3% vs. 9.4% and 16%). It is concluded that the new cryoloop vitrification technique followed by ICSI produce good embryo formation results and they could hold the future for effective oocyte cryopreservation.
冷冻环是一种技术，即使用细尼龙环悬挂含有卵母细胞的冷冻保护剂薄膜，并将其直接浸入液氮中。收集了508枚牛卵母细胞，其中351枚通过使用标准细管缓慢冷冻或使用我们自制的冷冻环的新玻璃化方法进行冷冻保存，其余作为对照。解冻后，卵母细胞通过卵胞浆内单精子注射（ICSI）或标准体外受精（IVF）进行授精。冷冻环玻璃化方法的存活率为90.5%，缓慢冷冻技术的存活率为54.4%（p<0.0001）。当进行ICSI时，冷冻环玻璃化方法冷冻保存后的卵裂率与对照组非常相似（16.0%对17.3%），但缓慢冷冻的卵裂率略低（9.4%）。新鲜卵母细胞IVF后的卵裂率高于冷冻保存组（49.5%对15.4%和25.8%），而ICSI后所有组的卵裂率相似（17.3%对9.4%和16%）。结论是，新的冷冻环玻璃化技术结合ICSI可产生良好的胚胎形成结果，它们可能为有效的卵母细胞冷冻保存带来未来的希望。
