E-Mail IMAGE: Deep imaging of a mouse femur bone marrow showing that Osteolectin-expressing cells (red) are around arterioles (white) but not sinusoids (green). view more Credit: UT Southwestern Medical Center Scientists at the Children's Medical Center Research Institute at UT Southwestern (CRI) have identified the specialized environment, known as a niche, in the bone marrow where new bone and immune cells are produced. The study, published in Nature, also shows that movement-induced stimulation is required for the maintenance of this niche, as well as the bone and immune-forming cells that it contains. Together, these findings identify a new way that exercise strengthens bones and immune function.