Studies of anti-FcepsilonRI autoantibodies in non-remitting allergic diseases.

为了分析与I型变态反应相关的疾病中的组胺释放自身抗体，对慢性荨麻疹（134例）、过敏性鼻炎（43例）、特应性皮炎（70例）和健康对照（114例）患者进行了自体血清皮肤试验。其中阳性反应五十六例（42.4%），阳性反应0例（0%），阳性反应3例（4.3%），阳性反应2例（2.6%）。荨麻疹和特应性皮炎患者血清组胺浓度均高于健康对照组，而细胞组胺含量荨麻疹组为1.1%，特应性皮炎组高于健康对照组。提示荨麻疹组胺释放自身抗体具有疾病特异性，特应性皮炎患者细胞及血清组胺总量增加。我们采用双向扩散血浆置换治疗重度慢性荨麻疹，取得了较好的效果。用来自健康志愿者的嗜碱性粒细胞进行的组胺释放试验显示，约70.4%的自体血清皮肤试验阳性患者的血清显示出明显的组胺释放活性，其中抗FcepsilonRI型活性高于抗IgE型活性。为了建立一种简便的检测自身抗体的方法，我们将人受体胞外区与大鼠受体跨膜区和胞内区嵌合的Fc ε RI导入大鼠肥大细胞系（RBL-3D 4）。该细胞系稳定表达细胞外结构域c人Fc ε RI α亚基，并响应抗Fc ε RI单克隆抗体或慢性荨麻疹患者而脱颗粒。对荨麻疹患者血清的初步筛选表明，该细胞系比人嗜碱性粒细胞具有特异性和易操作性，但敏感性较低。如何应用该细胞进行自身抗体的研究，提高其灵敏度，是今后研究的课题。

In order to analyze histamine releasing autoantibodies in diseases associated with type I allergy performed skin test by autologous sera for patients with chronic urticaria (134), allergic rhinitis (43) atopic dermatitis (70) and healthy controls (114). Fifty-six(42.4%), 0(0%), 3(4.3%) and 2(2.6%) of them showed positive reactions. Serum histamine concentrations of patients with urticaria and those atopic dermatitis were higher than those of healthy controls, but cellular histamine contents were I in patients with urticaria and higher in patients with atopic dermatitis than healthy controls. These results suggested disease specificity of the histamine releasing autoantibodies for urticana and increase of the total amount of cellular and serum histamine in patient with atopic dermatitis. We treated patient with sever chronic urticaria by double diffusion plasmapheresis with reasonable effects. Histamine release test with basophils derived from a healthy volunteer showed sera of approximately 70.4% of the patients with positive skin test by their autologous sera showed apparent histamine releasing activities with predominance of anti-FcepsilonRI type over anti-IgE type activities. In order develop a convenient method for the detection of the autoantibodies, we introduced chimeric FcepsilonRI consisting of human extracellular domain and rat trausmembrane and intracellular domains o receptor into a rat mast cell line (RBL-3D4). The cell line stably expresses the extracellular domain c human FcepsilonRI alpha-subunit and degranulated in response to either anti-FcepsilonRI monoclonal antibody or of patients with chronic urticaria. A pilot screening of the sera of urticaria suggested the cell line is : specific and easy to use than human basophils, but less sensitive. The way of application of this cel for studies of the autoantibodies and the improvement of the sensitivity is a subject for future investigations.