In-vitro cytotoxic and pro-apoptotic effects of an Echinococcus granulosus antigen B nanoformulation on CT26 colorectal cancer cells

Background/Objectives In recent decades, many studies have examined the anticancer effects of parasites, but little attention has focused on enhancing these effects through nanotechnology, leaving a significant knowledge gap. Therefore, this study aims to enhance the in-vitro cytotoxic activity of Echinococcus granulosus Antigen B (AgB) against CT26 colorectal cancer cells using a nanoformulation. Methods This study used the colon tumor 26 (CT26) and Human foreskin fibroblast-3 (HFF-3) cell lines. Cells were treated with free or nanocapsulated AgB at 0.25, 0.5, and 1.0 mg/mL for 24, 48, and 72 h. MTT assay was used to evaluate cell viability, and Annexin V/PI staining was performed to assess apoptosis. Results The mean nanocapsule size was 180.35 nm, and the Polydispersity Index (PDI) was 0.2600. Scanning electron microscopy (SEM) confirmed that the nanocapsules were spherical. Cytotoxicity against CT26 cells increased with both concentration and incubation time for free and nanocapsulated AgB. Nanocapsulated AgB consistently showed higher cytotoxicity than free AgB at matched nominal formulation concentrations and time points. At 72 h, 1.0 mg/mL nanocapsulated AgB showed the highest cytotoxicity (28.6 ± 0.6%), followed by free AgB at the same concentration (18.7 ± 0.5%). In HFF3 cells, the maximum cytotoxicity was observed at 72 h with 1.0 mg/mL free AgB (4.7 ± 0.2%) and nanocapsulated AgB (3.7 ± 0.1%), which were lower than the corresponding values in CT26 cells. Conclusions In conclusion, the AgB-loaded nanoformulation exhibited greater in-vitro cytotoxic and pro-apoptotic effects against CT26 colorectal cancer cells than free AgB, although these preliminary findings require further in-vivo validation before any translational conclusions can be drawn.