Tumor-Targeted Chemoimmunotherapy with Immune-Checkpoint Blockade for Enhanced Anti-Melanoma Efficacy.

Affiliation

Key Laboratory of Drug Targeting, Ministry of Education, West China School of Pharmacy, Sichuan University, No. 17, Section 3, Southern Renmin Road, Chengdu, 610041, People's Republic of China. [Email]

Abstract

Chemoimmunotherapy with chemotherapeutics and immunoadjuvant inhibits tumor growth by activating cytotoxic T cells. However, this process also upregulates the expression of PD-1/PD-L1 and consequently leads to immune suppression. To maximize the anti-tumor immune responses and alleviate immunosuppression, PD-L1 antibody was combined with paclitaxel (PTX) and the immunoadjuvant α-galactosylceramide (αGC), which were coencapsulated into pH-sensitive TH peptide-modified liposomes (PTX/αGC/TH-Lip) to treat melanoma and lung metastasis. Compared to treatment with PD-L1 antibody or PTX/αGC/TH-Lip alone, the combination of PD-L1 antibody and PTX/αGC/TH-Lip further elevated the tumor-specific cytotoxic T cell responses and promoted apoptosis in tumor cells, leading to enhanced anti-tumor and anti-metastatic effects. In adoptive therapy, PD-L1 antibody further alleviated immunosuppression and enhanced the anti-tumor effect of CD8+ T cells. The combination of PD-L1 antibody and chemoimmunotherapy PTX/αGC/TH-Lip provides a promising strategy for enhancing treatment for melanoma and lung metastasis.

Keywords

PD-L1 antibody,chemo-immunotherapy,combined strategy,immunosuppression,α-galactosylceramide,