【Objective】 To investigate homing and engraftment of bone marrow cells (BMCs) from fully disparate or identical donor in a sensitized model. 【Methods】 Sensitized BALB/c mice established by allogeneic splenocytes transfusion were used as transplanted recipients. After 8 Gy of 60Co irradiation

the sensitized mice were received 1 × 107 C57BL/6 BMCs from C57BL/6 or BALB/c donor via tail vein. A homing assay was also performed by labeling donor cells with the cell tracker

CFSE. Frozen sections and cell suspensions from different tissues were analyzed at different time points (2

12

and 48 h post transplantation). Survivals were assessed post transplantation

and hematopoietic recovery was monitored weekly. 【Results】 Homing study showed BMCs from C57BL/6 had temporary increase in femur of sensitized recipient

but decreased later

and the BMCs decreased with time in spleen of sensitized recipients; while BMCs from BALB/c increased with time in femur and spleen of sensitized recipients. The sensitized mice received BMCs from C57BL/6 died between 12 to 15 days after transplantation

and hematopoietic recovery decreased with time; while the sensitized mice received BMCs from BALB/c got long-term survival

and hematopoiesis recovered rapidly. 【Conclusion】BMCs from a fully disparate donor were totally rejected in the sensitized model

while the BMCs from a fully identical donor got successful homing and engraftment in the sensitized model.