衰变加速因子及其所在膜微区在T淋巴细胞信号传递中的作用

低温抽提Jurkat细胞膜去污剂抗性的膜成分(DIG),检测Src家族酪氨酸激酶(PTK)及衰变加速因子(DAF)的分布情况。共聚焦扫描显微技术检测Jurkat细胞静息与交联状态下DAF分子对去污剂Triton-X100的抗溶性,以探讨其在Jur-kat细胞免疫识别中的作用,结果显示静息状态CD3对去污剂无抗溶性,而DAF与Lck有抗溶性。单抗交联后CD3对去污剂抗性有所增加。静息状态DAF与Src家族PTK特异分布于膜微区中,交联CD3可诱导CD3与膜微区特异性聚集,DAF所在的膜微区可能促进T细胞的免疫识别和信号传递作用。

The effect of decay-accelerating factor and the associated microdomains on T lymphocyte signal transduction

Detergent-insoluble glycolipid enriched domains(DIGs) of Jurkat cells were extracted at low temperature and the distribution of Src family PTKs and DAF was examined.DIGs of Jurkat cells was extracted and found that Src family PTKs and DAF were specifically aggregated.Immunofluorescene confocal microscopy(ICM) detected the resistance of detergent Triton-X100 at both rest and cross-linking condition.CD3 was sensitive to detergent extraction at rest condition,whereas DAF and Lck were not.Cross-linking of CD3 could lead to resistance to detergent extraction to some extent.When cells were treated with MβCD,the solubility of DAF and CD3 were increased regardless of cross-linking or not.The ability of assembly of Lck with membrane microdomains was also weakened in rest condition.Then DAF and Src family PTKs are specifically associated with membrane microdomains in rest condition,whereas cross-linking of CD3 can lead to the aggregation of CD3 with membrane microdomains.Membrane microdomains containing DAF can assist T cell immune recognition.