天疱疮自身抗体的靶抗原研究

Study on the Target Antigen of Autoantibodies in Pemphigus

目的 了解天疱疮自身抗体的靶抗原及其在表皮的超微定位。方法 采用直接和间接免疫荧光 (IF)、免疫印迹 (IB)及包埋后金标记间接免疫电镜 (gold IIEM )等方法检测 2 7例天疱疮 (PV 2 2例 ,PF 5例 )血清与表皮抗原的结合情况。结果 2 7例天疱疮直接和间接免疫荧光的阳性率分别为 10 0 %和 81.5 % ,表现为表皮细胞间有亮绿色荧光标记物呈网状分布。 2 1/ 2 2例PV血清与表皮提取物 13 0kD分子结合 ,2 / 5例PF血清与表皮提取物 160kD分子结合。对11例天疱疮 (9例PV ,2例PF)血清的间接免疫电镜研究结果显示 ,金颗粒均沉积在桥粒部位。结论 PV和PF的靶抗原分别是表皮 13 0kD和 160kD抗原 ,其超微结构均定位于桥粒。免疫印迹检查可作为鉴别PV和PF的重要辅助手段。

Objective To explore the target antigens of autoantibodies in pemphigus and their localization in epidermis.Methods The binding of the antigens in the sera and epidermis in 27 patients (PV22,PF5) was explored by immunoblotting (IB),direct or indirect immunofluorescense (IF) and colloid gold labeled post-embedded indirect immunogold electron microscopy (gold-IIEM).Results Direct and indirect immunofluresence revealed deposits on the surface of keratinocytes in the epidermis.The positive rate was 100% and 81.5%,respectively.When all the sera were analyzed by immunoblotting technique with extracts from separated epidermis,21/22 PV sera reacted with a single protein having an apparent molecular weight of 130kD.In contrast,2/5 PF sera reacted with a protein of approximately 160kD.Gold labeling goat anti-human IgG were observed bound predominantly to the normal desmosome by indirect immunoelectron microscopy.Conclusion PV antigen is a 130kD protein and PF antigen is a 160kD protein.The target antigen of autoantibody in pemphigus locates to desmosome in ultrastructure level.Immunoblotting is a most important method to differentiate PV from PF.