Hematopoietic stem cell-mesenchymal stromal cell interface (HSPC-MSC interface)

The heterotypic cell-cell interface between donor-derived CD34+ hematopoietic stem/progenitor cells (HSPCs) and host mesenchymal stromal cells (MSCs) is a fundamental component of the bone marrow microenvironment, or niche (Méndez-Ferrer et al., Nature, 2010). This interface facilitates the anchoring of HSPCs through adhesion molecules such as VLA-4 (integrin alpha-4/beta-1) binding to VCAM-1, and regulates their behavior via chemokine signaling, most notably the CXCR4-CXCL12 (SDF-1) axis (Sugiyama T, et al., Immunity, 2006). These interactions are essential for the homing of transplanted donor cells to the recipient's bone marrow and their subsequent proliferation and differentiation into mature blood cells (Petit I, et al., Nature Immunology, 2002). In hematologic diseases, this interface can become a sanctuary for malignant cells, providing protection from apoptosis and chemotherapy-induced stress (Levesque JP, et al., Blood, 2001). Pharmacological modulation of this interface, such as the use of the CXCR4 antagonist plerixafor, is a standard clinical practice for mobilizing HSPCs into the peripheral blood for transplantation (Broxmeyer et al., J Exp Med, 2005). Understanding the molecular cross-talk at this interface is crucial for improving engraftment rates and developing therapies that disrupt the protective niche in cancers like acute myeloid leukemia.

Other names

Heterotypic cell-cell interfaces between donor-derived CD34+ hematopoietic stem/progenitor cells and host mesenchymal stromal cellsBone marrow stem cell nicheHSPC-MSC crosstalkHematopoietic microenvironment

Disruption of the CXCR4-CXCL12 signaling axis or VLA-4/VCAM-1 adhesion to mobilize stem cells or enhance engraftment.