Department of Molecular Biotechnology and Health Sciences and Molecular and Preclinical Imaging Centers, University of Turin, Turin, Italy.
Mol Imaging Biol. 2013 Jun;15(3):307-15. doi: 10.1007/s11307-012-0603-x.
This study is aimed at demonstrating the in vivo potential of Gd(III)-loaded glucan particles (Gd-GPs) as magnetic resonance imaging (MRI)-positive agents for labeling and tracking phagocytic cells.
GPs were obtained from Saccharomyces cerevisae and loaded with the water-insoluble complex Gd-DOTAMA(C18)2. The uptake kinetics of Gd-GPs by murine macrophages was studied in vitro and the internalization mechanism was assessed by competition assays. The in vivo performance of Gd-GPs was tested at 7.05 T on a mouse model of acute liver inflammation.
The minimum number of Gd-GPs-labeled J774.A1 macrophages detected in vitro by MRI was ca. 300 cells/μl of agar, which is the lowest number ever reported for cells labeled with a positive T1 agent. Intravenous injection of macrophages labeled with Gd-GPs in a mouse model of liver inflammation enabled the MRI visualization of the cellular infiltration in the diseased area.
Gd-GPs represent a promising platform for tracking macrophages by MRI as a T1 alternative to the golden standard T2-based iron oxide particles.
本研究旨在证明负载钆（III）的葡聚糖颗粒（Gd-GPs）作为磁共振成像（MRI）阳性造影剂用于标记和跟踪吞噬细胞的体内潜力。
GPs 从酿酒酵母中获得，并负载水不溶性配合物 Gd-DOTAMA(C18)2。研究了 Gd-GPs 被小鼠巨噬细胞体外摄取的动力学，并通过竞争实验评估了内化机制。在 7.05T 下，在急性肝炎症的小鼠模型上测试了 Gd-GPs 的体内性能。
通过 MRI 体外检测到的最低数量的 Gd-GPs 标记的 J774.A1 巨噬细胞约为 300 个细胞/μl 琼脂，这是迄今为止用阳性 T1 造影剂标记的细胞报道的最低数量。在肝炎症的小鼠模型中静脉注射 Gd-GPs 标记的巨噬细胞，使病变区域的细胞浸润能够通过 MRI 可视化。
Gd-GPs 代表了一种通过 MRI 跟踪巨噬细胞的有前途的平台，可作为替代金标准基于 T2 的氧化铁颗粒的 T1 造影剂。
