mRNA Nanotherapy targeting Kv1.3 channels enables in vivo reprogramming of T cells for cancer therapy 2260072

Abstract Introduction Head and neck squamous cell carcinoma (HNSCC) is an aggressive cancer with a suboptimal immunotherapy response. T cell-mediated cytotoxicity is crucial for antitumor immunity; however, in HNSCC, tumor-infiltrating T cells are functionally impaired, partly due to downregulation of Kv1.3 potassium channels that support Ca2+-dependent effector functions. We developed a targeted mRNA nanotherapy to restore Kv1.3 expression in T cells. Methods Kv1.3 mRNA was synthesized via in vitro transcription and encapsulated within lipid nanoparticles functionalized with anti-CD5 antibodies (CD5-NPs) to ensure T cell specificity. Functional assays and flow cytometry were performed in vitro, and efficacy was tested in vivo using humanized NSG mice bearing Cal27 tumor xenografts. Results CD5-NPs selectively attached to and were internalized by T cells, delivering Kv1.3 mRNA into the cytosol. This resulted in upregulated Kv1.3 protein levels, enhanced Kv1.3 activity, and Ca²+ influx, leading to increased effector cytokine and cytotoxic molecule secretion in T cells. Local in vivo delivery of CD5-NPs reduced tumor growth and increased CD8+ T cell infiltration and granzyme B expression, demonstrating the restoration of antitumor activity. Conclusion Restoring Kv1.3 expression via CD5-NPs enhances Ca²+-dependent T cell effector functions, thereby overcoming the immune dysfunction in HNSCC. This study introduces a mechanistically informed mRNA nanotherapy platform with broad potential for T cell—based cancer immunotherapy. Funding Source NIH (grant 5R21 CA277341-02) to Dr. Laura Conforti Topic Categories Tumor Immunology: Checkpoints, Prevention, and Treatment (TIPT)