introduction: a number of potential cell adhesion molecules, which mediate essential cell-to-cell or cell-to-matrix interactions, are expressed on the surface of cd34+ hematopoietic progenitor cells (hpcs), including integrins, cd44, and cxcr4. these molecules are essential for homing process. in this study, we compared the changes of expression of cd44 and cxcr4 on the cd34+ hematopoietic prog...