CAJ | 학술논문

目的探讨肿瘤坏死因子(TNF)α在调节造血干/祖细胞(HS/PC)归巢中的增效作用及其机制.方法将荧光染料CFSE标记的脐血CD34+细胞移植入接受照射(对照组)或联合TNFα预处理(实验组)的BALB/c受鼠.移植后20 h,采用流式细胞术(FACS)检测脐血CD34+细胞在BALB/c受鼠中的分布(外周血、肝脏、肺脏)与归巢(骨髓、脾脏)特征,计算其相应的归巢效率;酶联免疫吸附实验(ELISA)检测BALB/c受鼠血清基质衍生因子(SDF)-1α水平;FACS检测TNFα预处理前、后脐血CD34+细胞表面CXCR4表达水平的变化;免疫组化法检测BALB/c受鼠骨髓及脾脏组织切片中SDF-1α的表达水平.结果脐血CD34+细胞主要归巢于BALB/c受鼠骨髓和脾脏;经TNFα预处理的实验组BALB/c受鼠骨髓归巢率[(0.65±0.13)%]显著高于对照组[(0.30±0.09)%,P<0.01];但TNFα预处理同时显著抑制脐血CD34+细胞归巢于BALB/c受鼠脾脏(P<0.01);不同剂量的TNFα预处理不影响受鼠血清SDF-1α水平;新鲜分离的脐血CD34+细胞与不同浓度TNFα共孵育18 h后,其表面CXCR4表达水平并无明显变化;但TNFα预处理受鼠骨髓龛组成细胞SDF-1α表达增高,且脾脏红髓区小梁动脉和小梁静脉内皮细胞SDF-1α表达增高.结论 TNFα通过提升骨髓龛SDF-1α浓度梯度促进HS/PC归巢于骨髓,这一发现将有助于为临床提供可行性HS/PC归巢增效剂.
목적 탐토종류배사인자(TNF)α재조절조혈간/조세포(HS/PC)귀소중적증효작용급기궤제.방법 장형광염료CFSE표기적제혈CD34+세포이식입접수조사(대조조)혹연합TNFα예처리(실험조)적BALB/c수서.이식후20 h,채용류식세포술(FACS)검측제혈CD34+세포재BALB/c수서중적분포(외주혈、간장、폐장)여귀소(골수、비장)특정,계산기상응적귀소효솔;매련면역흡부실험(ELISA)검측BALB/c수서혈청기질연생인자(SDF)-1α수평;FACS검측TNFα예처리전、후제혈CD34+세포표면CXCR4표체수평적변화;면역조화법검측BALB/c수서골수급비장조직절편중SDF-1α적표체수평.결과 제혈CD34+세포주요귀소우BALB/c수서골수화비장;경TNFα예처리적실험조BALB/c수서골수귀소솔[(0.65±0.13)%]현저고우대조조[(0.30±0.09)%,P<0.01];단TNFα예처리동시현저억제제혈CD34+세포귀소우BALB/c수서비장(P<0.01);불동제량적TNFα예처리불영향수서혈청SDF-1α수평;신선분리적제혈CD34+세포여불동농도TNFα공부육18 h후,기표면CXCR4표체수평병무명현변화;단TNFα예처리수서골수감조성세포SDF-1α표체증고,차비장홍수구소량동맥화소량정맥내피세포SDF-1α표체증고.결론 TNFα통과제승골수감SDF-1α농도제도촉진HS/PC귀소우골수,저일발현장유조우위림상제공가행성HS/PC귀소증효제.
Objective To investigate the role of tumor necrosis factor (TNF) α on the homing effi-ciency of hematopoietic stem/progenitor cells (HS/PC) into bone marrow and its mechanism. Methods CFSE-labeled umbilical cord blood (UCB) CD34+ cells were transplanted into irradiated (control group) or combined with TNFα prepared (experimental group) BALB/c recipient mice. The distribution in peripheral blood, liver, lung and homing characteristics in bone marrow and spleen of UCB CD34+ cells,in BALB/c re-cipient mice were determined 20 hours after xenotransplantation by flow cytometry (FACS) and their homing efficiency was calculated. ELISA was used to measure serum SDF-1α level. CXCR4 expression levels of on UCB CD34+ cells were assessed by FACS pre-/post-manipulation with TNFα. SDF-1α expression level in bone marrow and spleen was tested by immunohistochemistry. Results UCB CD34+ cells mainly homed into recipient mice bone marrow and spleen ; The homing efficiency in experimental group bone marrow [(0.65±0.13) %] was significantly higher than that in control ones [(0.30±0.09) %, P < 0.01] , whereas the homing efficiency in experimental group spleen was dramatically lower than that in control ones (P < 0.01) ; Treatment with TNFα did not affect recipient serum SDF-1α level; After 18 hours co-cultured with TNFα, the CXCR4e expression level on UCB CD34+ cells was similar to that on fresh ones; TNFα treatment induced sig-nificantly higher SDF-1α expression on osteoblastic and stromal cells in bone marrow, and reversed spleen SDF-1α gradient that was originally favorable for CD34+ cells homing. Conclusion TNFα enhances the homing efficiency of HS/PC via up-regulating SDF-1α gradient in bone marrow, and might be an useful enhancer for HS/PC homing in clinical practice.