Objective: To explore the role of paternal veto cells in preventing graft-versus-host disease (GVHD) after related HLA- haploidentical stem cell transplantation in mice.
Methods: MHC-haploidentical recipient B6CF1(H-2 b/d) mice pretreated with total body irradiation at 9.0 Gy for 4 h before transplantation. The recipient mice were divided into 4 groups, and in the irradiation group, only injection of 0.3 ml D-Hank's liquid was given through the tail vein; in the control group, the mice received injection through the tail vein of 4.5x10(6) bone marrow cells mixed with 3.0x10(7) spleen cells from C57BL/6 mice without the preventive measures of GVHD; the mice in the two experiment groups received cell transplantation in the same manner, and on day 4 after transplantation, 5.0x10(6) and 1.0x10(7)spleen cells from BALB/c mice were injected through tail vein, respectively. The hematopoietic recovery, engraftment and GVHD of the recipient mice were observed.
Results: Without any treatment, all mice in the control group developed GVHD and died after transplantation. In the 10 mice with injection of 5.0x10(6) spleen cells, GVHD occurred in 5 mice with a 30-day survival rate of 50%; the median survival time of the mice with GVHD was 20 days, significantly longer than that of the control mice (14 days, P<0.05). In the 10 mice injected with 1.0x10(7) spleen cells, 2 developed GVHD and the 30-day survival rate was 80% (8/10) with a median survival time of 30 days, significantly longer than that of mice with injection of 5.0x10(6) spleen cells and the control mice (P<0.05).
Conclusion: Paternal veto cell transplantation can decrease the occurrence of GVHD after related HLA haploidentical stem cell transplantation in mice.