아토피피부염 환자에서 프로테오믹스 기법을 이용한 혈청 자가항체와 반응하는 각질형성세포 단백의 발굴

Abstract

Until now, the pathogenesis of atopic dermatitis has been explained by immunologic and environmental factors. Recently, autoimmunity theory emerged as a mechanism in pathogenesis of atopic dermatitis and many autoantigens have been discovered. IgE mediated hypersensitivity to autoantigen is thought to be a important aggravating factor for atopic dermatitis. In this paper, we would like to find out autoantigens in the epidermis that reacts with autoantibody in the sera of atopic dermatitis patients through proteomics and identify its characteristics and relationship. According to Hanifin and Rajka´s classification, we collected 48 atopic dermatitis patients and 5 normal patients sera and performed ELISA to verify the existence of IgE and IgG autoantibody against proteins of cultured keratinocytes. As a result, in the group of atopic patient the titer of the IgE autoantibody was slightly higher. We sorted out serums which showed higher values in ELISA test and performed immunoblot against keratinocyte protein. Keratinocyte proteins of 45-65 kd that didn´t react with sera of normal control reacted with IgE autoantibody in the patient group. Variable molecular size proteins of keratinocyte reacted with IgG antibody in sera of both patients and controls. To verify the 45-65 kd keratinocyte protein spot, we performed a 2-dimensional immunoblot using cultured keratinocyte protein. Through 2-dimensional immunoblot, we confirmed the site of the protein spot and found the protein by separating the site in the electrophoresis gel. Keratinocyte antigens which reacted with serum IgE autoantibody of atopic dermatitis patients were to be ATP synthase beta chain (56 kd, PI 5.3) and heat shock protein 60 (60 kd, PI 5.7). In this study, we observed the existence of autoantibodies to proteins of cultured keratinocytes in the sera of atopic dermatitis patients and identified autoantigens. These results will be used as fundamental data in understanding the pathogenesis of atopic dermatitis.