microRNA expression profiles in two- and three-dimensional culture conditions of human-umbilical-cord blood-derived CD34+ cells

Mesenchymal stem cells from different sources for sepsis treatment: prospects and limitations

Sepsis is a systemic inflammatory response syndrome in which the host response to infection is dysregulated, leading to circulatory dysfunction and multi-organ damage. It has a high mortality rate and its incidence is increasing year by year, posing a serious threat to human life and health. Mesenchymal stem cells (MSC) have the following properties: hematopoietic support, provision of nutrients, activation of endogenous stem/progenitor cells, repair of tissue damage, elimination of inflammation, immunomodulation, promotion of neovascularization, chemotaxis and migration, anti-apoptosis, anti-oxidation, anti-fibrosis, homing, and many other effects. A large number of studies have confirmed that MSC from different sources have their own characteristics. This article reviews the pathogenesis of sepsis, the biological properties of MSC, and the advantages and disadvantages of different sources of MSC for the treatment of sepsis and their characteristics.

The spatiotemporal heterogeneity of the biophysical microenvironment during hematopoietic stem cell development: from embryo to adult

Hematopoietic stem cells (HSCs) with the ability to self-renew and differentiate are responsible for maintaining the supply of all types of blood cells. The complex and delicate microenvironment surrounding HSCs is called the HSC niche and can provide physical, chemical, and biological stimuli to regulate the survival, maintenance, proliferation, and differentiation of HSCs. Currently, the exploration of the biophysical regulation of HSCs remains in its infancy. There is evidence that HSCs are susceptible to biophysical stimuli, suggesting that the construction of engineered niche biophysical microenvironments is a promising way to regulate the fate of HSCs in vitro and ultimately contribute to clinical applications. In this review, we introduced the spatiotemporal heterogeneous biophysical microenvironment during HSC development, homeostasis, and malignancy. Furthermore, we illustrated how these biophysical cues contribute to HSC behaviors, as well as the possible mechanotransduction mechanisms from the extracellular microenvironment into cells. Comprehending the important functions of these biophysical regulatory factors will provide novel approaches to resolve clinical problems.

Biomechanical cues as master regulators of hematopoietic stem cell fate

Hematopoietic stem cells (HSCs) perceive both soluble signals and biomechanical inputs from their microenvironment and cells themselves. Emerging as critical regulators of the blood program, biomechanical cues such as extracellular matrix stiffness, fluid mechanical stress, confined adhesiveness, and cell-intrinsic forces modulate multiple capacities of HSCs through mechanotransduction. In recent years, research has furthered the scientific community's perception of mechano-based signaling networks in the regulation of several cellular processes. However, the underlying molecular details of the biomechanical regulatory paradigm in HSCs remain poorly elucidated and researchers are still lacking in the ability to produce bona fide HSCs ex vivo for clinical use. This review presents an overview of the mechanical control of both embryonic and adult HSCs, discusses some recent insights into the mechanisms of mechanosensing and mechanotransduction, and highlights the application of mechanical cues aiming at HSC expansion or differentiation.