Abstract: Objective To investigate the effects of allogenic intra-bone marrow bone marrow transplantation ( IBM-BMT) on re-establishing hematopoiesis in mice. Methods Bone marrow mononuclear cells (BMNCs) from BALB/c mice were transplanted into the C57BL/6 mice treated with a lethal dose of 60Coγ-ray radiation either by intra-bone marrow injection or intravenous injection. Sixty of the C57BL/6 mice were randomly divided into three groups as higher dose intra-bone marrow injection group (IBM1 group), lower dose intra-bone marrow injection group (IBM2 group) and intravenous injection group (IV group) with 20 in each group. The nucleated cell numbers of whole bone marrow from the tibia of each recipient mouse were counted respectively at the day 1, day 3, day 6 and day 9 after the transplantation. The numbers of donor-derived total nucleated cells and myeloid cells were further analyzed by flow cytometry. Results At 6th day after transplantation, the numbers of total bone marrow nucleated cells, total donor-derived nucleated cells and donor-derived myeloid cells in the tibia of injected side in both IBM1 group and IBM2 group were all significantly higher than those in IV group (P＜0.05 or P＜0.01). Conclusion Compared with traditional bone marrow transplantation (IV-BMT), IBM-BMT improves the bone marrow hematopoiesis in the early hematopoietic re-establishing stage in allogenic bone marrow transplantation.

Key words: intra-bone marrow injection, tail intravenous injection, hematopoietic recovery, allogenic bone marrow transplantation