hematopoietic stem/progenitor cells (hspcs) which give rise to different blood cell types are present within the bone marrow microenvironment, especially in flat bones such as skull, vertebrae, pelvis and chest. interacting factors such as stromal derived factor-1/cxcr4, very late antigen-4/vascular cell adhesion molecule-1, lymphocyte function-associated antigen-1/ intercellular adhesion molec...