Pioneering Adoptive Immunotherapy with Natural Killer Cells

Redirecting natural killer cells to potentiate adoptive immunotherapy in solid tumors through stabilized Y-type bispecific aptamer

Modulating interactions between immune effector cells and tumor cells in vivo using a bispecific aptamer (Ap) is a promising strategy for cancer immunotherapy. However, it remains a technical challenge owing to the complex and dynamic internal environment accompanied by severe degradation. Herein, by using a Y-shaped DNA scaffold, a bispecific and stabilized Y-type Ap is designed to redirect natural killer (NK) cells to enhance adoptive immunotherapy of hepatocellular carcinoma (HCC) solid tumors. Y-type Ap is constituted by the HCC-specific Ap TLS11a linked with the CD16-specific Ap through a Y-shaped DNA scaffold. Owing to the rigid structure, Y-type Ap shows high stability in 10% serum for over 72 h and resistance to denaturation by 8 M urea. Additionally, the Y-type Ap exhibits more potent avidity to bind with NK cells and tumor cells both in vitro and in vivo, resulting in higher cytokine secretion and excellent antitumor efficiency. Collectively, this study offers a translational platform for constructing stable bispecific Ap, offering considerable potential to enhance adoptive immunotherapy of solid tumors.

Equipping Natural Killer Cells with Specific Targeting and Checkpoint Blocking Aptamers for Enhanced Adoptive Immunotherapy in Solid Tumors

Herein, we propose an aptamer-equipping strategy to generate specific, universal and permeable (SUPER) NK cells for enhanced immunotherapy in solid tumors. NK cells were chemically equipped with TLS11a aptamer targeting HepG2 cells and PDL1-specific aptamer without genetic alteration. The dual aptamer-equipped NK cells exhibited high specificity to tumor cells, resulting in higher cytokine secretion and apoptosis/necrosis compared to parental or single aptamer-equipped NK cells. Interestingly, dual aptamer-equipped NK cells induced remarkable upregulation of PDL1 expression in HepG2 cells, enhancing checkpoint blockade. Furthermore, in vivo intravital imaging demonstrated high infiltration of aptamer-equipped NK cells into deep tumor region, leading to enhanced therapeutic efficacy in solid tumors. This work offers a straightforward chemical strategy to equip NK cells with aptamers, holding considerable potential for enhanced adoptive immunotherapy in solid tumors.