Sap30调节小鼠造血干细胞的损伤恢复和体外扩增

Sap30 limits injury recovery and ex vivo expansion capacity of mouse hematopoietic stem cells

目的:探究在5-氟尿嘧啶(5-FU)诱导损伤修复和体外培养条件下,Sap30基因缺失对小鼠造血系统的影响。方法:以野生型小鼠作为对照组,Sap30基因敲除小鼠作为实验组。(1)应用流式细胞术检测Sap30基因在对照组和实验组小鼠血液细胞中的表达,每组5~8只小鼠。(2)应用流式细胞术检测野生型小鼠和Sap30基因缺失小鼠外周血、骨髓和脾脏中B细胞、T细胞及髓系细胞比例,胸腺中T细胞比例,以及骨髓中造血干/祖细胞比例,每组5~8只小鼠;利用造血干细胞体外培养及体内移植技术,检测Sap30基因缺失对小鼠造血干细胞克隆形成、归巢及重建造血能力的影响,每组3~5只小鼠。(3)利用5-FU诱导的化疗模型,检测Sap30基因缺失对小鼠外周血中血细胞数目以及骨髓中造血干/祖细胞数目和比例的影响,每组4~5只小鼠。(4)利用造血干细胞体外培养模型,检测Sap30基因缺失对小鼠造血干/祖细胞体外扩增的影响,每组4~5只小鼠。结果:(1)相较于淋系细胞,Sap30基因在小鼠血液系统的髓系细胞中特异性高表达(P<0.05);(2)Sap30基因缺失对小鼠造血系统无显著影响(P>0.05),对小鼠造血干细胞重建造血能力及归巢能力无显著影响(P>0.05);(3)Sap30基因缺失显著促进了小鼠造血干/祖细胞在5-FU损伤后的再生(P<0.05);(4)Sap30基因缺失显著促进了小鼠造血干/祖细胞的体外扩增(P<0.05)。结论:Sap30基因缺失促进了小鼠造血干细胞在5-FU处理后的损伤恢复以及体外培养条件下的扩增。

AIM:To investigate the effect of Sap30 gene deletion on hematopoietic system of mice treated with5-fluorouracil(5-FU)and under ex vivo culture condition.METHODS:(1)The expression of Sap30 gene in different types of blood cells was detected by flow cytometry.(2)The proportions of B cells,T cells and myeloid cells in peripheral blood,bone marrow and spleen,the ratio of T cells in the thymus,and the frequencies of hematopoietic stem/progenitor cells in bone marrow were examined by flow cytometry.The colony-forming,homing and reconstitution abilities of hematopoietic stem cells(HSCs)were measured by ex vivo culture and transplantation assay.(3)5-FU treatment was used to mimic chemotherapy on mouse hematopoietic system,and flow cytometry was applied to examine the effect of Sap30 gene deletion on the recovery of hematopoietic cells.(4)The effect of Sap30 gene deletion on the expansion of hematopoietic stem/progenitor cells was measured via HSC ex vivo culture assay.RESULT:(1)Compared with lymphoid cells,Sap30 gene was highly expressed in myeloid cells(P<0.05).(2)Sap30 gene is dispensable for the maintenance of hematopoietic system at steady state in mice(P>0.05).In addition,Sap30 deletion did not change HSC homing and reconstitution ability(P>0.05).(3)Sap30 gene deletion significantly promoted the regeneration of hematopoietic stem/progenitor cells after5-FU injury(P<0.05).(4)Deletion of Sap30 gene significantly enhanced the expansion of hematopoietic stem/progenitor cells under ex vivo culture condition(P<0.05).CONCLUSION:Deletion of Sap30 gene promotes the injury recovery capacity of HSCs after 5-FU treatment and promotes HSC ex vivo expansion capacity.