Stiffness matters: A soft bone marrow organoid rejuvenates hematopoietic stem cells

A recent study published in Cell Stem Cell1 showed that matrix stiffness critically regulates hematopoietic stem cell (HSC) niche, and successfully engineered a soft bone marrow (BM) organoid to maintain and rejuvenate HSCs ex vivo. In addition, BM stiffening was also identified as a novel aging hallmark of the hematopoietic system. Together, these important findings implicate matrix stiffness as a fundamental biomechanical factor governing cell fate determination and aging of tissue-specific stem cells.