Mice carrying intreperitoneally growing Calu-1 cells showed significant reduction in tumour mass and number after intravenous therapy with 5T4FabV13-SEA(D227A).
We initially prepared B16 melanoma cells linked to SAg SEA via a fusion protein with a transmembrane sequence (TM), and demonstrated that SEA thus anchored on the tumor cell surface could elicit strong antitumor immunity.
The conceptual objective for developing the tumor targeted superantigen (TTS) ABR-217620 (naptumomab estafenatox, 5T4Fab-SEA/E-120), now in phase 3 studies for advanced renal cell cancer, was to selectively coat tumor cells with cytotoxic T lymphocytes (CTL) target structures functionally similar to natural CTL pMHC target molecules.
Systemic administration of SEA-H61D in vivo significantly inhibited tumor growth, with the treated group undergoing tumor necrosis and showing a strong infiltration of lymphocytes to the tumor area.
This genetically engineered B3 (scdsFv)-SEA fusion protein has bifunction of tumor targeting and tumor cell killing and shows its promises as an effective reagent for tumor-targeted immunotherapy.
Expression of SEA gene in bladder tumor cells by adenoviral vector caused reduced tumor cell proliferation, as well as stimulation of inflammatory cytokine productions in co-cultures with lymphocytes.