Toso C, Vallee J-P, Morel P, Ris F, Demuylder-Mischler S, Lepetit-Coiffe M, Marangon N, Saudek F, James Shapiro A M, Bosco D, Berney T
Cell Isolation and Transplantation Center, Geneva University Hospitals, Geneva, Switzerland.
Am J Transplant. 2008 Mar;8(3):701-6. doi: 10.1111/j.1600-6143.2007.02120.x.
There is a crucial need for noninvasive assessment tools after cell transplantation. This study investigates whether a magnetic resonance imaging (MRI) strategy could be clinically applied to islet transplantation. The purest fractions of seven human islet preparations were labeled with superparamagnetic iron oxide particles (SPIO, 280 microg/mL) and transplanted into four patients with type 1 diabetes. MRI studies (T2*) were performed prior to and at various time points after transplantation. Viability and in vitro and in vivo functions of labeled islets were similar to those of control islets. All patients could stop insulin after transplantation. The first patient had diffuse hypointense images on her baseline liver MRI, typical for spontaneous high iron content, and transplant-related modifications could not be observed. The other three patients had normal intensity on pretransplant images, and iron-loaded islets could be identified after transplantation as hypointense spots within the liver. In one of them, i.v. iron therapy prevented subsequent visualization of the spots because of diffuse hypointense liver background. Altogether, this study demonstrates the feasibility and safety of MRI-based islet graft monitoring in clinical practice. Iron overload (spontaneous or induced) represents the major obstacle to the technique.
细胞移植后对非侵入性评估工具有着迫切需求。本研究调查磁共振成像（MRI）策略是否可临床应用于胰岛移植。将七种人胰岛制剂的最纯部分用超顺磁性氧化铁颗粒（SPIO，280微克/毫升）标记，并移植到四名1型糖尿病患者体内。在移植前及移植后的不同时间点进行MRI研究（T2*）。标记胰岛的活力以及体外和体内功能与对照胰岛相似。所有患者在移植后均可停用胰岛素。第一名患者基线肝脏MRI上有弥漫性低信号图像，这是自发高铁含量的典型表现，未观察到与移植相关的改变。其他三名患者移植前图像强度正常，移植后可将含铁负荷的胰岛识别为肝脏内的低信号点。其中一名患者，静脉铁剂治疗导致后续因肝脏弥漫性低信号背景而无法观察到这些低信号点。总之，本研究证明了基于MRI的胰岛移植监测在临床实践中的可行性和安全性。铁过载（自发或诱导）是该技术的主要障碍。
