Enhancing breast Cancer immunotherapy using gold nanoparticles carrying tumor antigens.

Cancer immunotherapy combined with standard treatments could provide an effective approach to enhancing anti-tumor responses. Activating antigen-presenting cells, such as dendritic cells (DCs), plays a central role in generating robust anti-tumor immune responses. Freund's adjuvant together with nanoparticles (NPs) and tumor antigens, promotes significant immune responses and shift antigen-specific T-cell activity from a Th2 to a Th1 response. Herein, Freund's adjuvant was combined with gold nanoparticles and tumor cell lysate (TCL). The AuNPs exhibited a spherical morphology. The in vitro release studies demonstrated a continuous and gradual release of AuNPs and TCL from Freund's adjuvant. The immunogenicity studies revealed high levels of cytokine secretion for IFN-γ, IL- 1, IL- 18, and TCD8+, along with reduced levels of IL- 4 cytokine in immunized mouse models in various treatment groups. In the prophylactic group, tumor growth was delayed, while in the therapeutic group, mouse models had more than 85% reduction within 31 days compared to the control group. The tumor size in the combination strategies, shrank to ~ 86% of its first size in just 17 days after treatment, while the control group tumor size increased by approximately 52%. These data suggest that the proposed drug system is an effective anti-tumor vaccine and also potentiate innate or adaptive immune responses for cancer therapy.