Discarded portions of bone marrow aspirates are a new resource for patient-derived mesenchymal stem and stromal cells

Bone marrow-derived mesenchymal stem and stromal cells (BM-MSCs) protect malignant cells from chemotherapy and are important potential therapeutic targets. Isolating primary BM-MSCs for research traditionally requires the sacrifice of valuable cell populations from within the same sample. To avoid this, we report here a resource for isolating patient-derived BM-MSCs from the red blood cell layer of ficoll gradients of bone marrow aspirates, a resource that has until now been universally discarded. This resource yields BM-MSCs nearly identical to those obtained conventionally and includes cells with a more stem-cell like nature. Obtaining primary BM-MSCs in this way will likely expand opportunities to study this important cell population.