Hematopoietic stem and progenitor cells and their niche (HSPC niche)

Hematopoietic stem and progenitor cells (HSPCs) are the foundation of the blood system, capable of self-renewal and differentiation into all mature blood lineages (National Cancer Institute, 2023). Their function is tightly regulated by the niche, a specialized microenvironment within the bone marrow composed of various cell types, such as osteoblasts and endothelial cells, and signaling molecules like CXCL12 and Stem Cell Factor (Morrison & Scadden, 2014). This niche maintains HSPC quiescence and protects them from exhaustion, while also facilitating their mobilization into the bloodstream during stress or clinical intervention (Schofield, 1978). Dysregulation of the HSPC niche is a hallmark of hematologic malignancies like leukemia, where the leukemic niche can protect cancer cells from chemotherapy (Lander et al., 2015). Therapeutic strategies often focus on mobilizing HSPCs for transplantation using CXCR4 antagonists like Plerixafor or stimulating cell production with growth factors like G-CSF (De Clercq, 2009; Welte et al., 1996). Understanding the interplay between HSPCs and their niche is essential for advancing regenerative medicine and oncology.

Other names

Hematopoietic stem cell nicheBone marrow nicheHematopoietic microenvironmentHSPC niche

Drugs targeting this system typically act by mobilizing HSPCs from the niche into peripheral blood (e.g., CXCR4 antagonism), stimulating progenitor proliferation (e.g., G-CSF/TPO mimetics), or modifying the niche to eliminate malignant cells.