冷冻保存

Abstract(#br)The maintenance of cell membrane integrity is an absolute minimum criterion for the selection of a successful cryopreservation process; however, it is often used as the sole determinant of cell “viability”. Membrane stresses and strains that develop with cell volume fluctuations are only one component of the overall cellular response to freezing. Damage to organelles resulting from excessive concentration of intracellular solutes and/or the alternation of molecular signalling events may affect post-thaw outcomes.

Abstract(#br)Animal cells are generally cryopreserved in cryovials in a cell suspension state containing 5%–10% v/v dimethyl sulfoxide (DMSO) used as a cryoprotective agent. However, cryopreservation of cells in an attached state has not been intensively studied, and the effective freezing solution remains unknown. Here we determined the suitable DMSO concentration for the cryopreservation of human hepatoma HepG2 cells attached to glass and polydimethylsiloxane (PDMS) matrices coated with poly- l -lysine.

Aim: to verify new techniques for human cadaveric vascular allografts cryopreservation, thawing and sterilization for the tissue engineering purposes. We use polydimethylsiloxane (PDMS) as a well-known, promising coolant. This allowed us to completely omit any cryoprotective or vitrifying solutions. Using of PDMS also makes possible an applying these allografts directly after freezing and decellularization and also it will also provide an opportunity to develop secure protocols of tissue— engineered vascular conduits cryopreservation. Matherial and methods.

目标。以聚二甲基硅氧烷为冷却剂和冷冻保护剂，建立了一种安全的髂动脉节段从死后供体取出后直接冷冻的方法。材料与方法。11段髂动脉取自死后供血者，分为4组，包括对照组。基于初步的热、冷传递数学建模和组织等效模体动脉节段的试验，置于塑料悬置上，按以下方案进行冷藏：第1、2组分别浸入聚二甲基硅氧烷中，180℃/ min快速冷却至-75℃。第3组切片置于-80℃冰箱中的PDMS冷冻容器中，1，6℃/ min冷冻保存。所有节段均在PDMS中浸泡24 °解冻，采用组织学方法和SEM观察其形态变化，并利用AzTech软件进行EDS分析，评价Si含量。对2组节段进行限制性生物力学测试。结果。除降温较慢的节段外，对照和冷冻保存组的节段间没有明显的形态学差异。结论。移动式超低温保存可能会提高大量供体组织的检索效率，以便以后可能用于血管生物假体的加工；或者，去细胞后，以及组织工程血管的组织特异性基质。