Benson C T, Liu C, Gao D Y, Critser E S, Benson J D, Critser J K
Cryobiology Research Institute, Wells Research Center, Indiana University Medical School, West Walnut Street, Indianapolis, Indiana, 46202, USA.
Cryobiology. 1998 Dec;37(4):290-9. doi: 10.1006/cryo.1998.2124.
Long-term cryopreservation of islets of Langerhans would be advantageous to a clinical islet transplantation program. Fundamental cryobiology utilizes knowledge of basic biophysical characteristics to increase the understanding of the preservation process and possibly increase survival rate. In this study several of these previously unreported characteristics have been determined for individual islet cells isolated from Golden hamster islets. Using an electronic particle counting device and a temperature control apparatus, dynamic volumetric response of individual islet cells to anisosmotic challenges of 1.5 M dimethyl sulfoxide (DMSO) and 1.5 M ethylene glycol (EG) were recorded at four temperatures (8, 22, 28, and 37 degreesC). The resulting curves were fitted using Kedem and Katchalsky equations which describe water flux and cryoprotectant agent (CPA) flux based on hydraulic conductivity (Lp), CPA permeability (Ps), and reflection coefficient (final sigma) for the membrane. For Golden hamster islet cells, Lp, Ps, and final sigma for DMSO at 22 degreesC were found to be 0.23 +/- 0.06 microm/min/atm, 0.79 +/- 0.32 x 10(-3) cm/min, and 0.55 +/- 0.37 (n = 11) (mean +/- SD), respectively. For EG at 22 degreesC, Lp equaled 0.23 +/- 0.06 microm/min/atm, Ps equaled 0.63 +/- 0.20 x 10(-3) cm/min, and final sigma was 0.75 +/- 0.17 (n = 9). Arrhenius plots (ln Lp or ln Ps versus 1/temperature (K)) were created by adding the data from the other three temperatures and the resulting linear regression yielded correlation coefficients (r) of 0.99 for all four plots (Lp and Ps for both CPAs). Activation energies (Ea) of Lp and Ps were calculated from the slopes of the regressions. The values for DMSO were found to be 12.43 and 18.34 kcal/mol for Lp and Ps (four temperatures, total n = 52), respectively. For EG, Ea of Lp was 11.69 kcal/mol and Ea of Ps was 20.35 kcal/mol (four temperatures, total n = 58).
朗格汉斯胰岛的长期冷冻保存对临床胰岛移植计划将是有利的。基础低温生物学利用基本生物物理特性的知识来增进对保存过程的理解，并有可能提高存活率。在本研究中，已确定了从金黄地鼠胰岛分离出的单个胰岛细胞的几个此前未报道的特性。使用电子粒子计数装置和温度控制设备，在四个温度（8、22、28和37摄氏度）下记录了单个胰岛细胞对1.5M二甲亚砜（DMSO）和1.5M乙二醇（EG）的非等渗挑战的动态体积响应。所得曲线使用凯德姆和卡查尔斯基方程进行拟合，该方程基于膜的水力传导率（Lp）、冷冻保护剂（CPA）渗透率（Ps）和反射系数（最终σ）来描述水通量和冷冻保护剂通量。对于金黄地鼠胰岛细胞，22摄氏度下DMSO的Lp、Ps和最终σ分别为0.23±0.06微米/分钟/大气压、0.79±0.32×10⁻³厘米/分钟和0.55±0.37（n = 11）（平均值±标准差）。对于22摄氏度下的EG，Lp等于0.23±0.06微米/分钟/大气压，Ps等于0.63±0.20×10⁻³厘米/分钟，最终σ为0.75±0.17（n = 9）。通过添加来自其他三个温度的数据创建了阿伦尼乌斯图（ln Lp或ln Ps对1/温度（K）），所得线性回归对所有四个图（两种CPA的Lp和Ps）产生的相关系数（r）为0.99。Lp和Ps的活化能（Ea）根据回归斜率计算得出。DMSO的Lp和Ps值在四个温度下（总n = 52）分别为12.43和18.34千卡/摩尔。对于EG，Lp的Ea为11.69千卡/摩尔，Ps的Ea为20.35千卡/摩尔（四个温度，总n = 58）。
