Department of Bioengineering and Therapeutic Sciences, University of California - San Francisco, San Francisco, CA 94158, USA.
Lab Chip. 2017 May 16;17(10):1778-1792. doi: 10.1039/c7lc00096k.
Diffusion-based bioartificial pancreas (BAP) devices are limited by poor islet viability and functionality due to inadequate mass transfer resulting in islet hypoxia and delayed glucose-insulin kinetics. While intravascular ultrafiltration-based BAP devices possess enhanced glucose-insulin kinetics, the polymer membranes used in these devices provide inadequate ultrafiltrate flow rates and result in excessive thrombosis. Here, we report the silicon nanopore membrane (SNM), which exhibits a greater hydraulic permeability and a superior pore size selectivity compared to polymer membranes for use in BAP applications. Specifically, we demonstrate that the SNM-based intravascular BAP with ∼10 and ∼40 nm pore sized membranes support high islet viability (>60%) and functionality (<15 minute insulin response to glucose stimulation) at clinically relevant islet densities (5700 and 11 400 IE per cm) under convection in vitro. In vivo studies with ∼10 nm pore sized SNM in a porcine model showed high islet viability (>85%) at clinically relevant islet density (5700 IE per cm), c-peptide concentration of 144 pM in the outflow ultrafiltrate, and hemocompatibility under convection. These promising findings offer insights on the development of next generation of full-scale intravascular devices to treat T1D patients in the future.
基于扩散的生物人工胰腺(BAP)设备由于传质不足导致胰岛缺氧和葡萄糖-胰岛素动力学延迟,因此受到胰岛活力和功能差的限制。虽然基于血管内超滤的 BAP 设备具有增强的葡萄糖-胰岛素动力学,但这些设备中使用的聚合物膜提供的超滤流量不足,导致过度血栓形成。在这里,我们报告了硅纳米孔膜(SNM),与用于 BAP 应用的聚合物膜相比,它具有更大的水力渗透性和更好的孔径选择性。具体来说,我们证明了基于 SNM 的血管内 BAP,其具有约 10nm 和 40nm 孔径的膜,在体外对流条件下,在临床相关的胰岛密度(5700 和 11400IE/cm)下支持高胰岛活力(>60%)和功能(<15 分钟胰岛素对葡萄糖刺激的反应)。在猪模型中具有约 10nm 孔径的 SNM 的体内研究表明,在临床相关的胰岛密度(5700IE/cm)下,具有高胰岛活力(>85%),流出超滤液中的 C 肽浓度为 144pM,并且在对流条件下具有血液相容性。这些有希望的发现为开发下一代全规模血管内设备以治疗未来的 T1D 患者提供了思路。