Abstract:

Objective  To investigate the distributionand the chimerism features after infusion of allogeneic bone marrow cells (BMCs) in rats. Methods  BMCs of SD rats were PKH26 labeled and 5×10-7 cells were infused to Wistar rats via the portal or inferior vena cava. Rapamycin was injected daily from day 0 to 4 after surgery. On day 7 and 14,the recipient rats were sacrificed and the blood, the BMCs, the thymus, the livers, the spleens, and the lymph nodes were collected. The lymphocytes of these organs were separated and then were analyzed by flow cytometry to detect the PKH26 labeled BMCs. The smear of peripheral blood mononuclear cells, the smear BMCs,and frozen tissue sections of the thymus, lymph nodes, the livers, and the spleens were observed with a fluorescence microscope. Results  Both flow cytometry and fluorescence microscopy demonstrated that BMCs injection induced mixed chimerism in adopted Wistar rat organs of the thymus, the liver, the spleen, and the lymphnode. The chimerism level was higher when injected via the portal vein than viathe inferior vena cava. Fluorescence microscopy detected the distribution features of PKH26 labeled cells in those organs, and indicated that donor BMCs can differentiate in those organs and be finally eliminated in the spleens. Conclusion  BMCs infusion can induce mixed chimerism in recipient organs with different distribution features, and portal vein infusion is a more effective strategy than inferior vena cava infusion.

Key words: Bone marrow cell; Portal vein; Tolerance; Chimerism;Rats