OBJECTIVETo establish a transplantation system for a trace amount of adult mouse bone marrow hematopoietic stem cells (HSCs).

METHODSThe HSCs from bone marrow cells of GFP adult mouse were seperated by using marker combination ESLAM (CD45CD201CD150CD48) The goal cell population acquired by flow cytometry sorting were injected into lethally irradiated recipient mouse plus protective cells. And the peripheral blood cells from recipient mice tail veins at different time points were acquired to observe the reconstruction level and lineage differentiation. Then the receptor mouse was killed and the cells from thymus, spleen, marrow, and peripheral blood were acquired to measure tissue chimerism.

RESULTSThe results of peripheral blood of recipient mice after transplantation showed that the reconstructive efficiency was 100% after 4th week. The proportion of GFP cells at different time points in various lines (myeloid, erythroid, B, T and megakaryocytes) were different and the change tendency of reconstruction were different. From different tissues (peripheral blood, bone marrow, spleen, thymus) after 6 months, the intramedullary spleen and thymus chimerism can be seen and showed a high proportion of GFPcells in the peripheral blood erythroid and megakaryocytes and there were no GFPcells in the myeloid and lymphatic cells, but the myeloid cells in the bone marrow cells of the recipient mice contained a higher proportion of GFPcells. The B cells in the spleen had a higher proportion of GFP cells, and the T cells in the thymus contained a higher proportion of GFP cells.

CONCLUSIONThe ESLAM combination can be highly efficient one for the enrichment of HSCs with long-term reconstructive ability, and the results of peripheral blood 6 months after the transplantation suggests that it may have the inclination to erythroid and megakaryocyte differentiation.