论文部分内容阅读
目的 阐明白细胞介素 18(IL 18)在人白血病细胞系J6 1的表达与调控 ,探讨IL 18在白血病发生中的意义。方法 应用逆转录浆合酶链反应检测IL 18mRNA的表达 ,酶切鉴定其特异性 ;构建IL 18的重组质粒 ,测序分析其cDNA序列的同源性 ;应用反义核酸技术 ,观察不同浓度的IL 18反义寡脱氧核苷酸 (ASODN)对J6 1细胞增殖的影响。结果 J6 1细胞组成性高表达IL 18mRNA ,测序结果表明 ,其cDNA序列与文献报道IL 18的同源性为 99% ,仅有一处同义点突变 (35UCA→UCC)。正常人外周血单个核细胞 (PBMC)IL 18mRNA的表达水平很低 (0 13± 0 0 5 ) ,CpG寡脱氧核苷酸 (CpG ODN)显著上调IL 18在PBMC的表达 (0 82± 0 2 4) ,但对J6 1细胞无类似上调作用。IL 18在J6 1细胞的表达水平 (0 98± 0 2 9)明显高于在K5 6 2、HL 6 0、U937和LCL细胞系的表达。IL 18ASODN能显著抑制J6 1细胞的增殖 (抑制率 43 3% ) ,而对HL 6 0的抑制作用不明显 (抑制率16 7% )。结论 J6 1细胞组成性高表达IL 18;IL 18基因的编码区在J6 1细胞不存在有意义的突变 ;IL 18可能通过自分泌途径正向调节J6 1细胞的增殖。
Objective To elucidate the expression and regulation of interleukin 18 (IL 18) in human leukemia cell line J61 and to explore the significance of IL 18 in leukemogenesis. Methods The expression of IL 18 mRNA was detected by reverse transcriptional-plasma synthase chain reaction and its specificity was identified by enzyme digestion. The recombinant plasmid of IL 18 was constructed and sequenced for homology of the cDNA sequence. Antisense nucleic acid technology was used to observe different concentrations of IL. Effect of antisense oligodeoxynucleotide (ASODN) on proliferation of J6 1 cells. Results The IL-18 mRNA was highly expressed in the J6 1 cells. The sequencing results showed that the cDNA sequence was 99% homologous to IL 18 in the literature, with only one synonymous point mutation (35UCA→UCC). The expression level of IL 18 mRNA in peripheral blood mononuclear cells (PBMC) of normal individuals was very low (0 13 ± 0 05). CpG ODN significantly up-regulated the expression of IL 18 in PBMCs (0 82 ± 0 2). 4) but no similar upregulation of J61 cells. The expression level of IL 18 in J61 cells (0 98 ± 0 2 9) was significantly higher than that in K562, HL 60, U937 and LCL cell lines. IL 18ASODN significantly inhibited the proliferation of J61 cells (43 3% inhibition), while the inhibitory effect on HL 60 was not obvious (inhibition rate 167%). Conclusions J18 cells have highly constitutively expressed IL 18; the coding region of IL 18 gene has no significant mutation in J61 cells; IL 18 may positively regulate the proliferation of J6 1 cells through the autocrine pathway.