Homing of stem cells to sites of inflammatory brain injury after intracerebral and intravenous administration: a longitudinal imaging study

Introduction This study aimed to determine the homing potential and fate of epidermal neural crest stem cells (eNCSCs) derived from hair follicles, and bone marrow-derived stem cells (BMSCs) of mesenchymal origin, in a lipopolysaccharide (LPS)-induced inflammatory lesion model in the rat brain. Both eNCSCs and BMSCs are easily accessible from adult tissues by using minimally invasive procedures and can differentiate into a variety of neuroglial lineages. Thus, these cells have the potential to be used in autologous cell-replacement therapies, minimizing immune rejection, and engineered to secrete a variety of molecules. Methods Both eNCSCs and BMSCs were prelabeled with iron-oxide nanoparticles (IO-TAT-FITC) and implanted either onto the corpus callosum in healthy or LPS-lesioned animals or intravenously into lesioned animals. Both cell types were tracked longitudinally in vivo by using magnetic resonance imaging (MRI) for up to 30 days and confirmed by postmortem immunohistochemistry. Results Transplanted cells in nonlesioned animals remained localized along the corpus callosum. Cells implanted distally from an LPS lesion (either intracerebrally or intravenously) migrated only toward the lesion, as seen by the localized MRI signal void. Fluorescence microscopy of the FITC tag on the nanoparticles confirmed the in vivo MRI data, Conclusions This study demonstrated that both cell types can be tracked in vivo by using noninvasive MRI and have pathotropic properties toward an inflammatory lesion in the brain. As these cells differentiate into the glial phenotype and are derived from adult tissues, they offer a viable alternative autologous stem cell source and gene-targeting potential for neurodegenerative and demyelinating pathologies. </br

Diagram of MR imaging with inversion recovery magnetization-prepared fast low angle shot (MP-FLASH) pulse sequence

<p><b>Copyright information:</b></p><p>Taken from "Assessment of myocardial infarction in mice by Late Gadolinium Enhancement MR imaging using an inversion recovery pulse sequence at 9.4T"</p><p>http://www.jcmr-online.com/content/10/1/6</p><p>Journal of Cardiovascular Magnetic Resonance 2008;10(1):6-6.</p><p>Published online 24 Jan 2008</p><p>PMCID:PMC2244610.</p><p></p> IR = inversion recovery pulse; ECG = electrocardiogram; AW = acquisition window; TI = inversion time (optimal inversion is TI= TI to null uninfarcted myocardium); TR= effective repetition time (depending on TI and heart beat)

Tuning sub-10 nm single-phase NaMnF3 nanocrystals as ultrasensitive hosts for pure intense fluorescence and excellent T1 magnetic resonance imaging

We report ultrasensitive sub-10 nm NaMnF3 nanocrystals codoped with Yb3+, Er3+/Tm3+ ions, and their intense pure red and near-infrared upconversion emissions in the presence of Mn2+. The nanocrystals showed excellent T1 contrast in 7 T MRI, implying their potential as single-phase contrast agents for fluorescent deep tissue and MR imaging

Single-phase NaDyF4:Tb3+ nanocrystals as multifunctional contrast agents in high-field magnetic resonance and optical imaging

The current work reports single-phase, terbium-doped sodium dysprosium fluoride (NaDyF4:Tb3+) nanocrystals with green luminescence and good T2 contrast in 7.0-T MRI phantom and animal imaging. The current nanocrystals demonstrate good potential as a dual modal contrast agent for high-field magnetic resonance (MR) and fluorescence imaging