An EWS::FLI1 monoclonal antibody with multimodal utility and specificity for FLI1

Ewing sarcoma (ES) is a rare tumor that affects children, adolescents, and young adults. This tumor has a high morbidity in all patients and for those who present with metastatic disease a high mortality. A canonical chromosomal translocation, either t(11;22)(q24;p12) or t(21;22)(q22;q12) leads to the fusion oncoproteins EWS::FLI1 or EWS::ERG in 95% of ES patients. We recognized a critical need for a stably sourced high affinity antibody that recognizes EWS::FLI1 with maximal specificity. We created and validated a hybridoma that produces a mouse derived monoclonal antibody that recognizes EWS::FLI1 in multiple molecular biology applications.