SLE患者T细胞PKA活性及血清因子对PKA活性的影响

Study on PKA Activity of T Cells from Patients with SLE and Serum Factor on PKA Activity in Normal T Cells

目的:研究SLE患者T细胞功能异常是否与T细胞CA/cAMP/PKA信号传导途径存在异常有关,探讨SLE的发病机理。方法:用尼龙柱分离肝素化的静脉血得到T细胞悬液,用流式细胞术测定CD_3阳性细胞90％以上,用CD_3单抗与羊抗鼠二抗IgG相交联和rIL-1α共同刺激T细胞24 小时,用RT-PCR检测IL-2和IL-2R mRNA的表达,证实T细胞是否活化。用PKA检测试剂盒检测T细胞PKA总体活性变化,用SLE血清或含不同浓度IFN-α的完全培养基和正常人T细胞培养24小时,然后用上述方法激活T细胞,分别测量T细胞PKA的总体活性。结果:SLE患者T细胞活化后PKA总体活性是下降的,SLE患者血清免疫复合物及不同浓度的IFN-α都不能使正常人T细胞的PKA总体活性下降。SLE患者T细胞活化后总体PKA活性下降和血清中的免疫复合物及血中高浓度的IFN-α无关。结论:1,SLE患者T细胞CA/cAMP/PKA信号传导途径存在异常。2,SLE患者T细胞功能异常是原发的,是由于细胞内生物化学信号途径异常所致。

Objective:To demonstrate the relationship between SUE T cells primary function disorder and abnormal AC/cAMP/PKA biochemical pathways. Methods: Human T lymphocytes were isolated by nylon immunoaffinity columns, T lymphocytes were isolated and enriched from PBMC by nylon im-munoaffinity columns, cytofluorographic analysis of enriched T lymphocyte over 90% possessed the CD3 membrane complex. SLE and control T cells were activated in vitro by monoclonal anti - CD3-ε antibody cross - linking sheep anti - mouse antibody IgG and recombinant IL -1 α(rIL - 1α) for 24 hours, T cells activation was verified by IL - 2 mRNA, IL - 2R - α, mRNA and IL - 2R - β mRNA expression . Total PKA activity of T cells was quantified by liquid scintillation spectrometry. Results: Total PKA activity of SLE T cells diminished after T cell activation. Neither SLE sera or IFN - a showed on any infnence on total PKA activity in control. Conclusion: T cells from active SLE possesed a metabolic disorder of the AC/cAMP/PKA pathway. A primary T cell disorder existing in SLE is the by - product of abnormal biochemical pathways.