Objective: To explore the dynamic changes of donor derived T cells at different time points in the aplastic anemia mouse model. Methods: The aplastic anemia mouse model was induced and then the proportion of infiltrated donor derived T cells in spleen and bone marrow, expression of activation molecular markers, cell cycle and functional subsets were measured by flow cytometry at different time points to evaluate the functional status of T cells in different periods. Results: ①T cell immune-mediated aplastic anemia mouse model was successfully established by half lethal dose irradiation combined with major histocompatibility antigen (MHC) haploidentical lymph node cells infusion. ②The donor derived T cells began to infiltrate significantly in the spleen of aplastic anemia mouse from the 3rd day after transplantation and the ratio of CD4(+)/CD8(+) gradually inverted. After the 5th day, they gradually entered the bone marrow, predominated by CD8(+) cells. ③The expression peak of CD69 in donor CD4(+) cells was later than that in CD8(+) cells. The trend of CD25 expression in CD4(+) cells was the same as that in CD8(+) cells, but the expression level in CD8(+) cells was higher than CD4(+) cells. ④The proportion of donor CD4(+) cells in S/G(2)/M phase reached the peak in spleen, about 12%, within 3 days after transplantation, while a higher level in CD8(+) cells, which was about 20%. And the proportion of both CD4(+) and CD8(+) cells in S/G(2)/M phase increased again after entering bone marrow, which was continued to be higher in CD8(+) cells than that in CD4(+) cells after 3 days of transplantation. ⑤Immune activated T cells in the spleen rapidly differentiated into effector memory T cells (T(EM)) after a short central memory T cell (T(CM)) stage. After entering the bone marrow, some T(EM) differentiated into effector cells to further function. Conclusion: In the aplastic anemia mouse model, donor derived T cells activated rapidly after entering the allogenic recipient, reached its proliferation booming period and differentiated into T(EM) cells within 5 days. After 5 days, they began to enter the bone marrow to continue proliferate and damage hematopoiesis.
目的： 探索再生障碍性贫血（AA）小鼠模型中供者来源T细胞不同时间点动力学变化。 方法： 构建AA小鼠模型，分别于不同时间点采用流式细胞术测定模型小鼠脾脏与骨髓内供者T细胞比例、活化分子表达、细胞周期及功能亚群，评估不同时期T细胞功能状态。 结果： ①半致死剂量照射联合主要组织相容性抗原（MHC）半相合的淋巴结细胞输注成功构建T细胞免疫介导的AA小鼠模型。②AA小鼠脾脏中供者T细胞从移植第3天后开始明显浸润，并逐渐出现CD4(+)/CD8(+)比例倒置，第5天开始进入骨髓，以CD8(+)细胞浸润为主。③CD69在供者CD4(+)细胞中表达高峰晚于CD8(+)细胞，CD25在CD4(+)细胞与CD8(+)细胞中表达水平的变化趋势相同，但在CD8(+)细胞中的表达高于CD4(+)细胞。④脾脏内供者CD4(+)细胞S/G(2)/M期比例在移植后第3天即达高峰，约12%，而CD8(+)细胞中S/G(2)/M期比例在移植后第5天达高峰，约20%，且两者在进入骨髓后S/G(2)/M期比例均再次升高，但移植第3天后其比例在脾脏与骨髓CD8(+)细胞中持续高于CD4(+)细胞。⑤脾脏内免疫活化的T细胞经历短暂的中枢记忆T细胞（T(CM)）阶段后迅速分化为效应记忆T细胞（T(EM)），进入骨髓后部分T(EM)分化为效应细胞进一步发挥效应功能。 结论： AA小鼠模型中供者T细胞进入异体后迅速活化，5天内达增殖高峰，并完成向T(EM)细胞的分化，5天后开始进入骨髓进一步增殖损伤造血。.
Keywords: Anemia, aplastic; Autoimmunity; Kinetics; Mouse model; T cells.