Molecular Imaging of Bone Marrow Mononuclear Cell Survival and Homing in Murine Peripheral Artery Disease

Abstract

Introduction Bone marrow mononuclear cell (MNC) therapy is a promising treatment for peripheral artery disease (PAD). This study aims to provide insight into cellular kinetics using molecular imaging following different transplantation methods. Methods and Results MNCs were isolated from F6 transgenic mice (FVB background) that express firefly luciferase (Fluc) and green fluorescence protein (GFP). Male FVB and C57Bl6 mice (n=50) underwent femoral artery ligation and were randomized into 4 groups receiving: (1) single intramuscular (i.m.) injection of 2×106 MNC; (2) four weekly i.m. injections of 5×105 MNC; (3) 2×106 MNCs intravenously (i.v.); and (4) PBS. Cellular kinetics, measured by in vivo bioluminescence imaging (BLI), revealed near-complete donor cell death 4 weeks after i.m. transplantation. Following i.v. transplantation, BLI monitored cells homed in on the injured area in the limb, as well as to the liver, spleen, and bone marrow. Ex vivo BLI showed presence of MNCs in the scar tissue and adductor muscle. However, no significant effects on neovascularisation were observed as monitored by Laser-Doppler-Perfusion-Imaging and histology. Conclusion This is one of the first studies to assess kinetics of transplanted MNCs in PAD using in vivo molecular imaging. MNC survival is short lived and MNCs do not significantly stimulate perfusion in this model.

Consensus guidelines for the use and interpretation of angiogenesis assays

“…This becomes even clearer when the fate of injected cells, and their rapid disappearance even from syngeneic mouse is taken into account [609]. A very comprehensive review on the use of various immunocompromised mouse strains in hind limb ischemia models for human cell therapy validations has recently been published by Thomas et al [594] and provides valuable information on the choice of the proper model.…”

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Enhanced Therapeutic and Long-Term Dynamic Vascularization Effects of Human Pluripotent Stem Cell–Derived Endothelial Cells Encapsulated in a Nanomatrix Gel

“…Similar trends were observed when cells were injected into a hindlimb ischemia model. Monitoring of cell survival using bioluminescent imaging (BLI) demonstrated that mesenchymal stem cells (MSCs) disappeared by 6 days 10 or 20 days 11 post cell transplantation. Survival of hPSC-ECs in a hindlimb ischemia model was reported by only one study, which showed no detectable bioluminescence signals after 14 days 12 .…”