School of Biomedical Engineering and Sciences, Virginia Tech - Wake Forest University, Blacksburg, VA, USA.
Biomed Eng Online. 2010 Dec 10;9:83. doi: 10.1186/1475-925X-9-83.
Despite advances in transplant surgery and general medicine, the number of patients awaiting transplant organs continues to grow, while the supply of organs does not. This work outlines a method of organ decellularization using non-thermal irreversible electroporation (N-TIRE) which, in combination with reseeding, may help supplement the supply of organs for transplant.
In our study, brief but intense electric pulses were applied to porcine livers while under active low temperature cardio-emulation perfusion. Histological analysis and lesion measurements were used to determine the effects of the pulses in decellularizing the livers as a first step towards the development of extracellular scaffolds that may be used with stem cell reseeding. A dynamic conductivity numerical model was developed to simulate the treatment parameters used and determine an irreversible electroporation threshold.
Ninety-nine individual 1000 V/cm 100-μs square pulses with repetition rates between 0.25 and 4 Hz were found to produce a lesion within 24 hours post-treatment. The livers maintained intact bile ducts and vascular structures while demonstrating hepatocytic cord disruption and cell delamination from cord basal laminae after 24 hours of perfusion. A numerical model found an electric field threshold of 423 V/cm under specific experimental conditions, which may be used in the future to plan treatments for the decellularization of entire organs. Analysis of the pulse repetition rate shows that the largest treated area and the lowest interstitial density score was achieved for a pulse frequency of 1 Hz. After 24 hours of perfusion, a maximum density score reduction of 58.5 percent had been achieved.
This method is the first effort towards creating decellularized tissue scaffolds that could be used for organ transplantation using N-TIRE. In addition, it provides a versatile platform to study the effects of pulse parameters such as pulse length, repetition rate, and field strength on whole organ structures.
尽管移植手术和普通医学取得了进步,但等待移植器官的患者人数仍在不断增加,而器官供应却没有增加。这项工作概述了一种使用非热不可逆电穿孔(N-TIRE)的器官脱细胞方法,该方法与再种植相结合,可能有助于补充移植器官的供应。
在我们的研究中,在主动低温心脏模拟灌注下对猪的肝脏施加短暂但强烈的电脉冲。通过组织学分析和损伤测量来确定脉冲在脱细胞化肝脏方面的效果,作为开发可能与干细胞再种植一起使用的细胞外支架的第一步。开发了一个动态电导率数值模型来模拟所使用的治疗参数并确定不可逆电穿孔阈值。
发现 99 个单独的 1000V/cm100-μs 方波脉冲,重复率在 0.25 至 4Hz 之间,在治疗后 24 小时内产生了一个损伤。肝脏在保持完整胆管和血管结构的同时,在灌注 24 小时后显示出肝细胞索中断和细胞从索基底层剥落。数值模型在特定的实验条件下发现电场阈值为 423V/cm,这可能在未来用于规划整个器官脱细胞化的治疗。对脉冲重复率的分析表明,在 1Hz 的脉冲频率下,处理面积最大,间质密度评分最低。在灌注 24 小时后,最大密度评分降低了 58.5%。
这种方法是使用 N-TIRE 为器官移植创建脱细胞组织支架的首次尝试。此外,它为研究脉冲参数(如脉冲长度、重复率和场强)对整个器官结构的影响提供了一个多功能平台。