Autoantibodies in a cohort of sera that contain anti -Jo-1 (histidyl-tRNA synthetase) antibodies

METHODS Sera with anti-Jo-1 antibodies were identified through routine clinical laboratory analysis using an Addressable Laser Bead ImmunoAssay (ALBIA: QUANTA Plex 8, INOVA San Diego, CA). The QUANTA Plex assay also simultaneously detects antibodies to seven other autoantigens (see Table 1). Sera were also evaluated for the presence of the 60 kDa SS-A/Ro and 52 kDa Ro antigens by ELISA (INOVA). Autoantibodies to other autoantigens associated with myositis were detected by western blotting (EUROLINE-WB Myositis, Euroimmun, Lubeck, Germany). Clinical features were assessed by retrospective chart review. INTRODUCTION Autoantibodies directed against the cytoplasmic autoantigen Jo-1 (histidyl-tRNA synthetase) are a serological hallmark of patients that have myositis. In this study, we evaluated 35 sera that had antibodies to Jo-1 for the presence of antibodies to other autoantigens. A retrospective analysis of the clinical features of these patients was included in the study.