Serological and Immunological Determination of Auto-Antibodies Against Myositis-Associated Antigens in Systemic Lupus Erythematosus Patients using a Novel Immunoblot Assay

Jo-1, anti-Mi-2, anti-Ro52, anti-PM/Scl-100 and -75, anti-Ku, anti-SRP, anti-antii-PL-7, anti-PL-12, anti- EJ, and antiOJ are associated with myositis and are also found in systemic lupus erythematosus. Materials & methods: We studied serum of 170 patients with systemic lupus erythematosus (97 females & 63 males) had definite or probable myositis according to physicians, the clinical status of patients was determined from their medical records and 20 adults’ healthy controls. Sera were screened for anti- ANA IgG antibodies and Anti-dsDNAIgG antibodies by using ELISA kits obtained from AESKU Diagnostics. also11 autoantibodies were detected by using IgGimmunoblot kit were used (EUROLINE Myositis Profile3, Euroimmun AG, Germany). Results: The analysis revealed that Jo-1 were more frequencies were present in 76 patients with SE followed by Mi2 were present in 59 patients., Ku, SRP, PM-Scl75, PM-Scl100, Ro-52, PL-7, PL-12, EJ, and OJ were present in 46, 38, 34, 28, 28, 22, 19, 11 and 5 patients respectively. The immunoblot results showed the highest intensity of anti-Mi-2, anti-Ku, anti-PM/Scl-100, anti-SRP, anti-PL-12, anti-OJ in females more than males with rheumatoid arthritis diseases, while the anti-EJ, anti-PL-7, anti-Jo-1, and anti-PM-Scl75 showed lowest intensity was +/17, ++/48, ++/33, and ++/29 respectively in females. Conclusion: The level of these autoantibodies associated with myositis were detected in 170 patients with SLE. The present results indicate that it is clinically useful to determine the serum levels of myositis-associated autoantibodies in patients with SLE even when their underlying diseases are not myositis.