αTrop2/αCD3 bispecific protein engager-armed T cells (BATs) exhibit potent antitumor activity against nasopharyngeal carcinoma.

Abstract

Nasopharyngeal carcinoma (NPC) remains a highly aggressive malignancy with poor outcomes in advanced and recurrent disease. Although immune checkpoint inhibitors combined with chemotherapy improve survival, many patients still experience relapse or disease progression. Here, we developed a non-genetically modified cellular immunotherapy based on αTrop2/αCD3 bispecific protein engager-armed T cells (αTrop2/αCD3-BATs), targeting Trop2, which is highly expressed in NPC and minimally expressed in normal tissues. Molecular dynamics simulations supported stable dual binding of the BiPE to Trop2 and CD3ε, consistent with effective immune synapse formation. Functionally, αTrop2/αCD3-BATs exhibited potent, antigen-dependent cytotoxicity against Trop2-positive NPC cell lines (TW01, HK1, and CNE1) in both two-dimensional co-culture and three-dimensional spheroid models while sparing Trop2-negative cells. Target engagement induced robust T cell activation and proliferation, accompanied by increased expression of effector molecules such as FasL and elevated secretion of cytolytic mediators (perforin, granzymes, and granulysin) and pro-inflammatory cytokines (IFN-γ, TNF-α, and IL-2). Collectively, these findings demonstrate that αTrop2/αCD3-BATs mediate potent and selective antitumor activity and support their further preclinical development as an MHC-independent cellular immunotherapy for Trop2-positive NPC.