T-Cell-Derived Nanovesicles for Cancer Immunotherapy

Area of Science:

• Immunotherapy
• Nanotechnology
• Oncology

Background:

• T-cell therapy shows promise for cancer immunotherapy but faces limitations in solid tumors.
• Solid tumors create an immunosuppressive tumor microenvironment (TME) that causes T-cell exhaustion.
• Programmed death-ligand 1 (PD-L1) and transforming growth factor-beta (TGF-β) are key mediators of this immunosuppression.

Purpose of the Study:

• To develop T-cell-derived nanovesicles (TCNVs) that overcome the immunosuppressive TME in solid tumors.
• To investigate the mechanisms by which TCNVs inhibit T-cell exhaustion and exert anti-tumor activity.
• To evaluate the therapeutic efficacy of TCNVs in a preclinical solid tumor model.

Main Methods:

• TCNVs were produced from cytotoxic T cells via serial extrusion through micro-/nanoporous membranes.
• TCNVs were characterized for surface markers, including programmed cell death protein 1 (PD-1) and TGF-β receptor.
• The ability of TCNVs to block PD-L1, scavenge TGF-β, deliver granzyme B, and suppress tumor growth was assessed in vitro and in vivo.

Main Results:

• TCNVs possess PD-1 and TGF-β receptors on their surface, enabling them to block PD-L1 and scavenge TGF-β.
• TCNVs effectively prevented cytotoxic T-cell exhaustion within the immunosuppressive TME.
• TCNVs demonstrated direct anti-tumor activity through granzyme B delivery and significantly suppressed tumor growth in mice.

Conclusions:

• TCNVs represent a novel strategy for cancer immunotherapy, effectively overcoming solid tumor immunosuppressive mechanisms.
• TCNVs offer a dual mechanism of action: inhibiting immunosuppression and directly killing cancer cells.
• This approach holds potential for enhancing the efficacy of T-cell-based cancer therapies.