Strategies to enhance efficacy of SPION-labeled stem cell homing by magnetic attraction: a systemic review with meta-analysis

Stem cells possess a promising potential in the clinical field. The application and effective delivery of stem cells to the desired target organ or site of injury plays an important role. This review describes strategies on understanding the effective delivery of stem cells labeled with superparamagnetic iron oxide nanoparticles (SPION) using an external magnet to enhance stem cell migration in vivo and in vitro. Fourteen total publications among 174 articles were selected. Stem cell type, SPION characteristics, labeling time, and magnetic force in vivo are considered important factors affecting the effective delivery of stem cells to the homing site. Most papers reported that the efficiency was increased when magnet is applied compared to those without. Ten studies analyzed the homing competency of SPION-labeled MSCs in vitro by observing the migration of the cell toward the external magnet. In cell-based experiments, the mechanism of magnetic attraction, the kind of nanoparticles, and various stem cells were studied well. Meta-analysis has shown the mean size of nanoparticles and degree of recovery or regeneration of damaged target organs upon in vivo studies. This strategy may provide a guideline for designing studies involving stem cell homing and further expand stem cell.