B7-h3-specific engager T cells for the immunotherapy of pediatric solid tumors.

Background B7-H3 positive tumors, including osteosarcoma, neuroblastoma, and high grade glioma, cause significant morbidity and mortality despite aggressive multimodality treatments. Current B7-H3-targeted immune-therapies take advantage of the monoclonal antibody 8H9, which is actively being evaluated in Phase I clinical trials. Engager T cells, which secrete bispecific engager molecules consisting of single chain variable fragments specific for CD3 and a tumor antigen, are a new class of antigen-specific T cells, with the unique ability to redirect bystander T cells to tumors, amplifying anti-tumor effects. The goal of this project was to develop B7-H3-specific Engager T cells, and pre-clinically evaluate their effector function in vitro and in vivo.