OBJECTIVE: To determine the biochemical structure and antigenic components of Mi-2 autoantigen, the target of autoantibodies in 15-20% of dermatomyositis patients. METHODS: Immunoprecipitation from 35S-labeled HeLa cell extract, immunoblotting, and purification from bovine thymus by immunoaffinity chromatography. RESULTS: All 46 sera that had anti-Mi-2 autoantibodies demonstrated by immunodiffusion immunoprecipitated a major protein of approximately 240 kd. Additional proteins of 200, 150, 72, 65, 63, 50, and 34 kd appeared to be part of the antigen. Fractions of purified bovine Mi-2 with antigenic activity showed high molecular weight bands comparable with immunoprecipitated HeLa Mi-2. Twenty-four of 47 anti-Mi-2 positive sera reacted with the 240-kd protein by immunoblot against anti-Mi-2 immunoprecipitates. CONCLUSION: Mi-2 antigen consists of multiple proteins, of which the 240-kd protein appears to be the major reactive component.
OBJECTIVE: To determine the biochemical structure and antigenic components of Mi-2 autoantigen, the target of autoantibodies in 15-20% of dermatomyositispatients. METHODS: Immunoprecipitation from 35S-labeled HeLa cell extract, immunoblotting, and purification from bovine thymus by immunoaffinity chromatography. RESULTS: All 46 sera that had anti-Mi-2 autoantibodies demonstrated by immunodiffusion immunoprecipitated a major protein of approximately 240 kd. Additional proteins of 200, 150, 72, 65, 63, 50, and 34 kd appeared to be part of the antigen. Fractions of purified bovine Mi-2 with antigenic activity showed high molecular weight bands comparable with immunoprecipitated HeLa Mi-2. Twenty-four of 47 anti-Mi-2 positive sera reacted with the 240-kd protein by immunoblot against anti-Mi-2 immunoprecipitates. CONCLUSION: Mi-2 antigen consists of multiple proteins, of which the 240-kd protein appears to be the major reactive component.
Authors: Minoru Satoh; Shin Tanaka; Angela Ceribelli; S John Calise; Edward K L Chan Journal: Clin Rev Allergy Immunol Date: 2017-02 Impact factor: 8.667
Authors: Marcelo H Petri; Minoru Satoh; Beatriz T Martin-Marquez; Raul Vargas-Ramírez; Luis J Jara; Miguel A Saavedra; Claudia Cruz-Gonzalez; Lilia Andrade-Ortega; Olga Vera-Lastra; Mario Salazar-Páramo; Rosa E Prieto-Parra; Laura Gonzalez-Lopez; Jorge I Gamez-Nava; Hermes U Ramírez-Sánchez; Jason Y F Chan; Steven J Ross; Edward K L Chan; Mónica Vázquez-Del Mercado Journal: Arthritis Res Ther Date: 2013-04-04 Impact factor: 5.156