Featured Articles - January 25, 2021

Magnetic resonance imaging of human neural stem cells in rodent and primate brain
Lisa M. McGinley, et al., STEM CELLS Translational Medicine

Translation of cell therapies for central nervous system disorders is often limited by an inability to noninvasively identify and track transplanted cells in vivo. This article reports on a novel magnetic resonance imaging contrast agent based on magnetotactic bacteria that enables visualization and tracking of cell grafts in nonhuman primate and murine brain. Results suggest that with further optimization, these agents may be useful for determining graft survival or rejection. Overall, the findings of this study indicate that magneto‐endosymbionts are an effective tool for in vivo monitoring of cell‐based therapies with potential relevance to many neurological applications.

Mesenchymal stromal cells reprogram monocytes and macrophages with processing bodies
Hyunjung Min, et al., STEM CELLS

Mesenchymal stromal cells (MSCs) have been used in clinical trials for inflammatory diseases. MSCs are rapidly cleared within hours despite having long‐lasting effects in suppressing inflammation. The present study uncovered a novel mechanism by which umbilical cord‐derived MSCs reprogram monocytes and macrophages to suppress T cells. Macrophages engulf cytoplasmic components of MSCs and undergo transcriptional reprogramming. The interaction depends on lipoprotein receptor‐related proteins on macrophages and is mediated by processing bodies within MSCs. This study not only provides a novel mechanism but also uncovers novel potential therapeutic targets to enhance the immunomodulators capabilities of MSCs.