Author:
Jiang Qiping,Yao Fengjiao,An Yacong,Lai Xialian,Li Xundou,Yu Zhen,Yang Xian-Da
Abstract
Abstract
Background
PD-1/PD-L1 blockade plays a crucial role in cancer immunotherapy. Exploration of new technologies to further enhance the efficacy of PD-1/PD-L1 blockade is therefore of potential medical importance. Nanotherapeutics can accumulate in tumor tissues due to enhanced permeability and retention (EPR) effects. In this study, a novel nanotherapeutic for cancer immunotherapy was implemented with albumin nanoparticles functionalized by both PD-1 and PD-L1 aptamers.
Results
Albumin nanoparticles (NP) were functionalized with either PD-1 aptamers (PD1-NP), PD-L1 aptamers (PDL1-NP), or both types of aptamers (PD1-NP-PDL1). Average sizes of PD1-NP, PDL1-NP, and PD1-NP-PDL1 were 141.8 nm, 141.8 nm, and 164.2 nm, respectively. PD1-NP had good affinity for activated T cells that expresses PD-1. Similarly, PDL1-NP could bind with MDA-MB-231 or CT26 tumor cells that express PD-L1. Moreover, the bispecific PD1-NP-PDL1 could bind with both the activated T cells and the PD-L1-expressing tumor cells, and tether the two type of cells together. Functionally, aptamer-modified nanoparticles exhibited stronger immune-stimulating effects vs. free aptamers. Specifically, PD1-NP or PDL1-NP induced stronger lymphocyte-mediated cytotoxicity against PD-L1-expressing tumor cells in vitro vs. free PD-1 or PD-L1 aptamers. Animal studies also showed that PD1-NP or PDL1-NP significantly improved antitumor efficacy against CT26 colon cancer in vivo vs. free PD-1 or PD-L1 aptamers. Importantly, the bispecific PD1-NP-PDL1 further boosted the in vivo antitumor efficacy compared with PD1-NP or PDL1-NP, without raising systemic toxicity.
Conclusion
The results suggest that the bispecific PD1-NP-PDL1 is a promising nanotherapeutic to improve the efficacy of PD-1/PD-L1 blockade, and may have application potential in colon cancer treatment.
Funder
the Ministry of Science and Technology
Tianjin Science and Technology Plan Project
Publisher
Springer Science and Business Media LLC
Subject
Physical and Theoretical Chemistry,Pharmaceutical Science,Oncology,Biomedical Engineering