The Expanding Family of Bone Marrow Homing Factors for Hematopoietic Stem Cells: Stromal Derived Factor 1 Is Not the Only Player in the Game

The α-chemokine stromal derived factor 1 (SDF-1), which binds to the CXCR4 and CXCR7 receptors, directs migration and homing of CXCR4+ hematopoietic stem/progenitor cells (HSPCs) to bone marrow (BM) and plays a crucial role in retention of these cells in stem cell niches. However, this unique role o...

Full description

Saved in:
Bibliographic Details
Main Authors: Mariusz Z. Ratajczak, ChiHwa Kim, Anna Janowska-Wieczorek, Janina Ratajczak
Format: Article
Language:English
Published: Wiley 2012-01-01
Series:The Scientific World Journal
Online Access:http://dx.doi.org/10.1100/2012/758512
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The α-chemokine stromal derived factor 1 (SDF-1), which binds to the CXCR4 and CXCR7 receptors, directs migration and homing of CXCR4+ hematopoietic stem/progenitor cells (HSPCs) to bone marrow (BM) and plays a crucial role in retention of these cells in stem cell niches. However, this unique role of SDF-1 has been recently challenged by several observations supporting SDF-1-CXCR4-independent BM homing. Specifically, it has been demonstrated that HSPCs respond robustly to some bioactive lipids, such as sphingosine-1-phosphate (S1P) and ceramide-1-phosphate (C1P), and migrate in response to gradients of certain extracellular nucleotides, including uridine triphosphate (UTP) and adenosine triphosphate (ATP). Moreover, the responsiveness of HSPCs to an SDF-1 gradient is enhanced by some elements of innate immunity (e.g., C3 complement cascade cleavage fragments and antimicrobial cationic peptides, such as cathelicidin/LL-37 or β2-defensin) as well as prostaglandin E2 (PGE2). Since all these factors are upregulated in BM after myeloblative conditioning for transplantation, a more complex picture of homing emerges that involves several factors supporting, and in some situations even replacing, the SDF-1-CXCR4 axis.
ISSN:1537-744X