脐血T细胞IL-4基因表达及其调控

Interleukin-4 gene expression and its regulation in cord blood T cells

目的探讨脐血T细胞中活化T细胞核因子(NF AT)的活性与IL 4基因表达调控的关系。方法采用ELISA和RT PCR法测定受抗CD3 +PMA刺激后 ,18例脐血单个核细胞(CBMC)IL 4基因及其mRNA的表达 ;电泳迁移率转换试验(EMSA) ,测定10例CBMCNF AT的活性。22例成人外周血单个核细胞(PBMC)为对照。结果CBMC培养上清液中IL 4为(12.4±1.5)ng/L ,较PBMC明显低下〔(37.5±5.5)ng/L ,P∨0.01〕 ;CBMCIL 4mR NA的表达较PBMC明显减少 ;PBMC核蛋白内NF AT的活性较强 ,CBMC则几乎测不出NF AT的活性。结论在转录水平缺乏NF AT调控与脐血T细胞IL 4mRNA的转录水平低下有关 ;也是脐血T细胞表达IL 4水平低下的重要原因。

Aim To explore the possible correlation of nuclear factor of activated T cell (NF AT) activities with interleukin 4 (IL 4) gene expression and its regulation in cord blood T cells. Methods After stimulation with anti CD3 and PMA, in vivo IL 4 and its mRNA in 18 cord blood mononuclear cells (CBMC) were detected by using ELISA and RT PCR respectively, and the activity of NF AT was detected by using electrophoresis mobility shift assay (EMSA) in 10 CBMC activated T cell nuclear protein, as comparing with 22 normal adult peripheral mononuclear cells (PBMC). Results The mass concentrations of IL 4 in supernatants of CBMC (12.4±1.5)ng/L were significant lower than those of PBMC (37.5±5.5)ng/L,(P∨0.01). The IL 4 gene mRNA expressions in CBMC were significant lower than those in PBMC. The activities of NF AT in PBMC were detectable in our test system, but not in CBMC. Conclusion The lack of the regulation by NF AT at transcription level may be associated with insufficient transcription of IL 4 mRNA in cord blood T cells, and be an important cause of insufficient IL-4 production in cord blood T cells.