Revascularization plays a critical role in the successful engraftment of transplanted pancreatic islets, which are inherently rich in capillaries to meet their high metabolic demands. Innovative islet encapsulation strategies such as the NICHE (neovascularized implantable cell homing and encapsulation), generate a prevascularized transplantation site that allows for direct integration of the graft with the systemic circulation. Timing the transplantation is key to maximizing islet engraftment and survival, especially in diabetic individuals, who exhibit impaired wound healing. Therefore, in this study, we explored different methods to assess vascular development within NICHE in vivo in a non‐invasive fashion. We effectively tracked neoangiogenesis using nanoparticle contrast‐enhanced computed tomography (nCECT), observing a steady increase in vascularization over an 8‐week period, which was confirmed histologically. Next, we estimated relative vascularization changes via T2 mapping with magnetic resonance imaging (MRI) before and after islet transplantation. On the first day post‐transplantation, we measured a slight decrease in T2 values followed by a significant increase by day 14 attributable to islet revascularization. Our findings underscore the potential of non‐invasive imaging techniques to provide insightful information on the readiness of the transplant site within cell encapsulation systems to support cell graft transplantation.

中文翻译：

---

胰岛移植皮下壁龛血管形成的纳米颗粒造影增强计算机断层扫描和磁共振成像


血运重建在移植胰岛的成功植入中起着关键作用，胰岛本身富含毛细血管以满足其高代谢需求。创新的胰岛封装策略，如 NICHE（新生血管植入式细胞归巢和封装），可产生血管前移植部位，允许移植物与体循环直接整合。移植时机是最大限度地提高胰岛植入和存活率的关键，尤其是对于伤口愈合受损的糖尿病患者。因此，在这项研究中，我们探索了以非侵入性方式在体内评估 NICHE 内血管发育的不同方法。我们使用纳米颗粒对比增强计算机断层扫描 （nCECT） 有效地追踪新血管生成，观察到血管形成在 8 周内稳步增加，这得到了组织学证实。接下来，我们通过胰岛移植前后磁共振成像 （MRI） 的 T2 标测估计相对血管形成变化。在移植后的第一天，我们测量到胰岛血运重建的 T2 值略有下降，然后在第 14 天显着增加。我们的研究结果强调了非侵入性成像技术的潜力，可以提供有关细胞封装系统内移植部位准备情况的有见地信息，以支持细胞移植移植。