**Background of TrpRS Antibodies**
TrpRS (tryptophanyl-tRNA synthetase) antibodies are autoantibodies targeting the enzyme tryptophanyl-tRNA synthetase, a member of the aminoacyl-tRNA synthetase (ARS) family. These enzymes play a critical role in protein synthesis by attaching specific amino acids, such as tryptophan, to their corresponding tRNA molecules. TrpRS antibodies are primarily associated with idiopathic inflammatory myopathies (IIM), particularly polymyositis (PM) and dermatomyositis (DM), and are a hallmark of antisynthetase syndrome (ASS), a multisystem autoimmune disorder.
ASS is characterized by clinical features including myositis, interstitial lung disease (ILD), arthritis, and skin abnormalities. Among ARS autoantibodies, anti-Jo-1 (targeting histidyl-tRNA synthetase) is most common, while TrpRS antibodies (anti-WRS) are rarer but linked to distinct phenotypes, such as severe ILD and acute-onset myositis. Their presence aids in diagnosis, prognosis, and stratification of disease subtypes.
The origin of TrpRS autoimmunity remains unclear, though molecular mimicry, viral triggers, or aberrant enzyme exposure during tissue damage are hypothesized. Detection typically involves immunoassays (ELISA, immunoprecipitation) or line blot techniques. Clinically, TrpRS antibodies may correlate with treatment response and disease progression, though further studies are needed to clarify their pathogenic role. Current research focuses on epitope mapping, cross-reactivity, and their impact on cellular signaling beyond protein synthesis.