Transfusion donor cells before haploidentical bone marrow transplantation in mice

Objective To establish the mouse model of non-myeloablative haploidentical bone marrow transplantation（BMT） and study the outcome of donor hemopoietic stem cells transfusion before haploidentical BMT. Methods CB6F1 female mice were used as recipients and C57BL/6 male mice were used as donors.Three days before BMT,3×107 donor spleen cells or bone marrow cells were transfused through the tail vein.Then,Ara-C（0.015g/d） was injected into abdominal cavity 24h and 48h after transfusion of spleen cells or bone marrow cells.One day before BMT,the recipients received total body irradiation（TBI） at the dose of 450cGy.On the day of BMT,5×107 nucleared bone marrow cells from male donor mice were transfused.Restore of white blood cells and sex determining region Y gene（SRY） in recipients and chimerism in CD3+ cells of donors after BMT were monitored. Results The mice after simple TBI survived and their white blood cells became normal 30 days after BMT.PCR showed the SRY in peripheral blood 14,30 and 60 days in mice after TBI and BMT.The chimerism of CD3+ cells in donors on day 60 was 54.4% before BMT and 93.5%±4.8% after transplantation of spleen cells（P＜0.05）. Conclusion Non-myeloablative pretreatment with 450cGy TBI can establish the mouse model of non-myeloablative haploidentical BMT and transfusion of donor spleen cells before BMT can promote transplantation of hemopoietic stem cells.