肥大细胞类过敏反应脱颗粒的实时动态检测方法

目的 建立实时、动态、直接的肥大细胞脱颗粒光学成像检测方法.方法 将囊泡表面特异性分子CD63与绿色荧光蛋白(green fluorescence protein,GFP)的基因融合后,通过质粒转染入细胞中,建立稳定表达CD63-GFP蛋白的鼠肥大细胞株(RBL-2H3细胞).之后利用激光扫描共聚焦显微镜及全内反射显微镜分别观察细胞内囊泡在过敏原刺激下脱颗粒时的运动状况.结果 成功建立稳定表达CID63-GFP的RBL-2H3细胞株;在类过敏原的刺激下,用激光扫描共聚焦显微镜观察到了细胞脱颗粒过程中,细胞内囊泡向细胞外脱出的过程,同时,用全内反射显微镜观察到了细胞内囊泡与细胞膜融合的过程.结论 本研究在活细胞状态下,实时、直观、灵敏、快速地观察到肥大细胞脱颗粒的过程,直接评估过敏原刺激肥大细胞脱颗粒的特性,为类过敏反应的检测提供了新的检测手段.

Real-time detection of mast cell degranulation in anaphylactoid reaction

Objective: To establish a new, real time, dynamic and direct optical detection method for mast cell degranulation caused by anaphylactoid reaction. Method: A CD63-GFP plasmid was constructed and introduced steadily into rat basophilic leukemia (RBL-2H3) cells. The movements of CD63-GFP, which was located on both the granule membranes and the plasma membranes of RBL cells stimulated by Compound 48/80, were studied by confocal laser scanning microscope(CLSM) and total internal reflection fluorescence microscope (TIRFM) both inside and on the surface of living RBL-2H3 cells. Result: Before antigen stimulation, most granules with CD63-GFP hardly moved in RBL cells. However, after antigen stimulation, the granules moved dramatically. They reached the plasma membranes in a few minutes and fused with them instantaneously. The velocity of the granule movement toward the plasma membranes on antigen stimulation was calculated to be 0. 05 micron·s^-1. Conclusion: Analysis of the movement of each granule provided a new insight into the elementary process of degranulation. The method is rapid, sensitive and reliable, which could be used as a new detection method for anaphylactoid reaction in vitro.