H-2单倍体相合小鼠双供体造血干细胞移植模型的建立

摘要

Objective:To establish a new mouse model of H-2 haploidentical stem cell transplantation from double donors (DHSCT) and compare with conventional haploidentical hematopoietic stem cell transplantation (HSCT) so as to alleviate transplant-related complications.Methods:The recipients CB6F1 of conventional HSCT group were pretreated by 8 Gy total body irradiation (TBI),and received 3 × 107 donor (male C57) spleen mononuclear cells (spMNC) mobilized by G-CSF within 2 hours after TBI.Recipients CB6F1 of D-HSCT groups accepted 2 Gy TBI,and received total 12 × 107 spMNC mobilized by G-CSF from 2 donors within 2 hours after TBI,each donor donated 6 × 107 cells.According to the different strains and sex of donors,DHSCT were divided into 3 groups:in group A,the stem cells were from male C57 and female BALB/c;in group B,stem cells were from male C57 and male BALB/c,while the stem cells in group C were from male C57 and male C3H.Hematopoietic reconstruction,engraftment,GVHD and survival were observed among these 4 groups.Results:The nadir of white blood cell count after conventional HSCT were lower than 1 × 109/L and lasted for 3 to 5 days,while not less than 3 × 109/L after D-HSCT among either group A,B or C.The complete chimerism (CC) in conventional HSCT group was achieved quickly within only 1 week in peripheral blood.Mixed chimerism (MC) in peripheral blood was found within the first week after DHSCT among either group A,B or C,and transformed into stable CC within the second week eventually.Both GVHD morbidity and mortality of conventional HSCT were 100％ at 34th day after transplantation.Among DHSCT groups,the overall GVHD morbidity and mortality at 34th day after transplant were 49.6％ and 50％ (P ＜ 0.01,P ＜ 0.05),respectively,and 60.4％ and 81.2％ at 50th day after transplant.Overall survival of 50 days was 50.9％ that indicated a long survival in such mice DHSCT.The differences of hematopoietic reconstruction,donor cell engraftment,GVHD incidence,GVHD mortality and OS were not statistically significant among group A,B and C (P ＞ 0.05).Conclusion:A new mouse model of H-2 haploidentical peripheral blood stem cell transplantation from double donors (DHSCT) has been successfully established by reducing conditioning intensity and increasing graft cell numbers from double haploidentical donors without GVHD prophylaxis.DHSCT successfully achieved stable complete chimerism,less GVHD morbidity and mortality and longer OS without hematopoietic suppression.This study provides experimental evidence for clinical application of HLA haploidentical peripheral blood stem cell transplantation from double donors.%目的:建立新的H-2单倍体相合小鼠双供体造血干细胞移植模型并与经典的造血干细胞移植进行比较,以减轻移植的相关并发症.方法:建立H-2单倍体相合小鼠双供体外周血造血干细胞移植模型并与8Gy预处理移植组进行比较.在经典移植组给予CB6F1受鼠8 Gy TBI预处理,2h内回输经G-CSF动员的供体(雄性C57)脾单个核细胞(spMNC)3×107;在双供体移植(DHSCT)组给予CB6F1受鼠2 Gy TBI,2h内回输H-2单倍体相合小鼠双供体来源的spMNC共12×10 7(每个供体各6×10 7),依据供鼠组品系和性别不同,双倍体移植组又再分为3组:A组为雄性C57+雌性BALB/c,B组为雄性C57+雄性BALB/c,C组为雄性C57+雄性C3H.观察4组的造血重建、移植物植入、GVHD及存活情况.结果:经典移植组出现严重造血抑制,WBC＜1×109/L持续3-5d;A、B、C各组未出现造血抑制(WBC ＞3×109/L).经典移植组快速植入,1周达到外周血完全植入;A、B、C3组1周达混合植入,2周达完全植入.经典移植组34dGVHD发生率及致死率均为100％.双供体移植(DHSCT)组中34 d总体GVHD发生率及致死率分别为49.6％、50％ (P＜ 0.01,P＜0.05);50d分别为60.4％和81.2％,50 d总体存活率为50.9％.A、B、C各组的造血重建、供体植入、GVHD发生率、GVHD致死率、OS等均无显著差异(P＞0.05).结论:采用2 Gy TBI预处理、双供者细胞输注、无GVHD预防,可使供体完全稳定植入、无造血抑制、GVHD发生率及死亡率明显减少;研究表明,H-2单倍体相合小鼠双供体造血干细胞移植模型成功建立.