非清除性异基因骨髓移植治疗小鼠白血病的实验研究

目的　研究非清除性异基因骨髓移植 (BMT)及其加供者淋巴细胞输注 (DLI)治疗小鼠白血病是否在保留移植物抗白血病效应 (GVL)的同时 ,又能减轻移植物抗宿主病 (GVHD)及移植相关并发症。方法　采用L6 15淋巴细胞白血病小鼠模型 ,非清除性预处理后移植BALB c小鼠骨髓细胞和脾细胞。分 4组 :清除性BMT对照组 (A组 )、非清除性预处理组 (B组 )、非清除性BMT组 (C组 )、非清除性BMT +DLI组 (D组 )。通过受鼠生存期、外周血白细胞和L6 15细胞计数、死亡鼠尸解观察GVL效应 ;通过体重改变、弓背、翘毛、腹泻等表现和肝脏、小肠、皮肤病理学检查观察GVHD ;通过染色体检查和PCR检测嵌合状态。结果　A、B、C、D组生存时间分别为 (2 0 .3± 13.4 )d、(15 .9± 1.1)d、(2 1.6± 1.7)d和 (37.8± 2 .0 )d ,C组和A组生存时间无统计学意义 (P >0 .0 5 ) ,C组生存时间长于B组 (P <0 .0 1) ,D组长于C组 (P <0 .0 1) ;A组有 6 0 %出现GVHD表现及病理学改变 ,而C组和D组均无典型GVHD表现和病理学改变 ;A组有 4 0 %在 2周内死于移植相关并发症 ,C组和D组均无移植相关死亡发生 ;A组一直保持异基因嵌合 ,C组渐被排斥。结论　非清除性BMT有一定的GVL效应 ,加DLI能增强GVL效应 ;非清除性BMT能减轻GVHD及移植相关并发症。

Study on nonmyeloablative allogeneic bone marrow transplantation in the treatment of L615 leukemia mice

OBJECTIVE: To establish strategies for preventing graft versus host disease (GVHD) and reducing treatment associated morbidity while preserving graft versus leukemia (GVL) effect in nonmyeloablative allogeneic bone marrow transplantation (allo-BMT), with or without donor lymphocyte infusion (DLI) after BMT. METHODS: 3 x 10(7) bone marrow cells mixed with 1 x 10(7) spleen cells from the same BALB/c mouse were transplanted into the nonablative irradiated inbred 615 mouse which received a single subcutaneous injection of 1 x 10(6) L615 leukemia cells three days before. The experiments were designed as follows (ten mice in each group): myeloablative BMT control group (group A), nonmyeloablative conditioning without BMT group (group B), nonmyeloablative BMT group (group C), and nonmyeloablative BMT + DLI group (group D). GVL effects were assessed by survival time, white blood cell count and L615 cells in peripheral blood and histologic changes. GVHD was assessed by signs of weight loss, ruffled fur, diarrhea and histologic changes of skin, liver and small intestines. Chimerism was detected by cytogenetic analysis and PCR technique. RESULTS: The survival time of group A, B, C and D was (20.3 +/- 13.4), (15.9 +/- 1.1), (21.6 +/- 1.7) and (37.8 +/- 2.0) days, respectively, being no significant difference between group A and group C (P > 0.05). The survival time of group C was longer than that of group B (P < 0.01). And among group B, C and D, group D had the longest survival time (P < 0.01). GVHD signs and histologic changes were observed in 60% of control group mice at + 14 day, but none of group C and group D. 40% of mice in group A died of treatment associated morbidity within two weeks, but none in group C and group D. Allogeneic chimerism was kept in group A, but excluded gradually in group C. CONCLUSION: GVL effect seems preserved in nonmyeloablative BMT mice, but weaker than that in myeloablative BMT mice. GVL effect seems to be enhanced by DLI after nonmyeloablative BMT. GVHD and transplantation associated morbidity seems to be reduced in nonmyeloablative BMT.