N-Cadherin-Expressing Bone and Marrow Stromal Progenitor Cells Maintain Reserve Hematopoietic Stem Cells

？ rHSC and pHSCs are distinguished by their resistance or sensitivity to chemotherapy ？ pHSCs in the perivascular niche are largely eliminated by chemotherapy ？ rHSCs are maintained by N-cad+ cells and restore the HSC pool after chemotherapy ？ N-cad+ BMSPCs expand and produce SCF and other cytokines for rHSCs upon stres