免疫学因素对重症肌无力患者外周血单个核细胞糖皮质激素受体的影响

The effect of acetylcholine receptor and interferon-γ on the quantity of glucocorticoid receptor in peripheral blood mononuclear cells from patients with myasthenia gravis

目的 探讨重症肌无力 (MG)患者外周血单个核细胞 (PBMC)糖皮质激素受体 (GR)数改变的可能机制。方法 13例MG患者及 11例正常对照PBMC在体外与乙酰胆碱受体 (AChR)、IFN γ或AChR +IFN γAb孵育前后同时测定PBMCGR数及GRmRNA含量。3H 地塞米松 (3H Dex)放射配体法测定GR数 ,狭缝印迹杂交法测定GRmRNA量 ,以 β actincDNA为内对照。同时 ,ELISA法测定患者血浆中的IFN γ含量及AChRAb水平。结果 正常对照PBMC分别在AChR、IFN γ、AChR +IFN γAb中培养后其GR数虽有降低 ,但未达到统计学意义 (P >0 .0 5 )。MG患者PBMC的GR数在AChR及IFN γ中培养后明显降低 (与培养前相比 ,前者P <0 .0 5 ,后者P <0 .0 1) ,而在AChR +IFN γAb中培养后则无明显改变 (P >0 .0 5 )。正常对照PBMC分别在AChR、IFN γ、AChR +IFN γAb中培养后其GRmRNA无显著降低 (P >0 .0 5 )。MG患者PBMC的GRmRNA在AChR及IFN γ中培养后与培养前相比明显降低 (前者P <0 .0 5 ,后者P <0 .0 1) ,而在AChR +IFN γAb中培养后则无明显改变 (P >0 .0 5 )。MG患者的血浆中IFN γ及AChRAb水平均显著高于正常对照 (前者P <0 .0 1;后者P <0 .0 5 )。MG患者的IFN γ含量与AChRAb水平间具有良好的正相关关系 (r=0 .92 ,P <0 .0 1)。MG患者的PBMC在体?

Objective To explore the possible mechanism of glucocorticoid receptor (GR) alteration in peripheral blood mononuclear cells from patients with myasthenia gravis (MG). Methods GR number and GR mRNA of PBMC from 13 MG patients and 11 healthy controls were examined before and after incubation with AChR or IFN γ or AChR plus anti IFN γ antibody. GR was quantified by 3H dexamethansone radioligand binding assay. PBMC GR mRNA was measured by slot blotting using Digoxigenin labeled GR cDNA probe and Digoxigenin labeled β actin cDNA probe as internal control. IFN γ contents and AChR Ab levels in plasma from healthy controls and MG patients were measured by ELISA. Results GR number and GR mRNA of PBMC in healthy controls were slightly decreased after incubation with AChR, IFN γ or AChR+anti IFN γ Ab, but didn′t show statistical significance (compared to those before culture, P >0.05). GR number and GR mRNA of PBMC in MG patients were significantly decreased after incubation with AChR (compared to those before culture, P <0.05) and IFN γ( P <0.01) but not after incubation with AChR+anti IFN γ Ab ( P >0.05). IFN γ titer and AChR Ab levels in plasma from MG patients were significantly higher than those from healthy controls (the former: P <0.01; the latter: P < 0.05 ). There was a positive correlation between IFN γ contents and AChR Ab levels in plasma from MG patients ( r =0.92, P <0.01). IFN γ levels in plasma of MG patients and in supernatants of MG PBMC culture with AChR were significantly higher than those in healthy controls ( P <0.01). Conclusion GR expression of PBMC in MG patients was down regulated before GR mRNA transcription due to IFN γ up regulation stimulated by AChR. [