重组人肿瘤坏死因子-α体内外对HL-60细胞作用的研究

为了研究重组人肿瘤坏死因子-α（recombinant human tumor necrosis factor-alpha,rhTNF-α）在体外及体内对人髓系白血病细胞株HL-60细胞的作用,应用MTT法和集落形成试验测定HL-60细胞的增殖抑制,采用AO/EB荧光染色法、流式细胞术和TdT酶介导的缺口末端标记（TUNEL）法检测凋亡细胞;利用HL-60细胞裸鼠异种移植瘤模型观察给药后瘤体重量、组织病理的改变,并采用透射电镜以及TUNEL法检测瘤组织细胞的凋亡.结果表明：rhTNF-α对HL-60细胞的增殖具有明显的抑制作用,呈时间和浓度依赖性;AO/EB染色后可见rhTNF-α处理组HL-60细胞核内染色质浓缩聚集或成碎片,呈现凋亡表象;流式细胞术显示随着rhTNF-α浓度的增加,细胞凋亡阳性率逐渐增高;TUNEL法检测显示,3 200 U/ml rhTNF-α作用于HL-60细胞48小时凋亡阳性率可达37.5%.在体内,rhTNF-α可抑制HL-60细胞裸鼠异种移植瘤生长,抑制率最高可达60.33%;病理检查发现,rhTNF-α处理组的瘤组织有程度不等的出血坏死区域;透射电镜及TUNEL法检测表明,处理组的瘤组织可见有较多凋亡细胞.结论：rhTNF-α在体内、外均可抑制HL-60细胞增殖,并诱导其凋亡.

Effects of Recombinant Human Tumor Necrosis Factor-alpha on HL-60 Cells In Vitro and In Vivo

To study the effects of recombinant human tumor necrosis factor-alpha (rhTNF-alpha) on HL-60 cells in vitro and in vivo, MTT and colony forming assay were used to examine the effects of rhTNF-alpha on proliferation of HL-60 cells; AO/EB (acridine orange-ethidium bromide) staining, Annexin-V flow cytometry analysis and TUNEL assay were used to detect apoptotic cells. The effect of rhTNF-alpha on xenograft growth of HL-60 cells was evaluated by tumor inhibition rate, histology, ultrastructure and TUNEL assay. The results showed that rhTNF-alpha inhibited the proliferation of HL-60 cells in a dose-dependent manner. Staining of cells with AO/EB revealed that rhTNF-alpha induced nuclear chromatin condensation and fragmentation. Positive Annexin V-FITC on cell membrane showed that rhTNF-alpha induced apoptosis of HL-60 cells in a dose-dependent manner. TUNEL assay showed that the apoptotic percentage of HL-60 cells reached 37.5% when incubated with 3200 U/ml rhTNF-alpha for 48 hours. In vivo rhTNF-alpha inhibited xenograft growth of HL-60 cells with the highest inhibition rate of 60.33%. Pathologically it was found that there were necrotic areas in the tumors of groups treated with rhTNF-alpha. There were more apoptotic cells in treatment groups than in that control group by transmission electron microscopy (TEM) and TUNEL assay. It is concluded that rhTNF-alpha is able to inhibit the proliferation of HL-60 cells and to induce apoptosis of HL-60 cells in vitro and in vivo.