Live Imaging of Stem Cells: Answering Old Questions and Raising New Ones

The document from December 1, 2016, reviewed the impact of live imaging technology on stem cell research, revealing new insights into stem cell behavior, interactions with their niches, and responses to injury. It highlighted discoveries such as the interconvertibility of spermatogonial stem cells in the mouse testis, the role of the spindle assembly checkpoint in C. elegans germline stem cells, and the dynamic interactions between hematopoietic stem cells (HSCs) and their bone marrow environment. Live imaging has shown that epidermal stem cells in the basal layer are equipotent, that dying cells in mouse hair follicles are phagocytosed by neighboring cells, and that HSCs change behavior in response to infection. It also revealed that tissue architecture guides stem cell behavior during wound repair and that β-Catenin activation in the hair stem cell niche regulates tissue growth. These findings have advanced our understanding of stem cell dynamics, tissue maintenance, repair, and cancer development, emphasizing the importance of live imaging in uncovering complex biological processes and the need for further research using fluorescent reporters and optogenetic tools.