Fig. 4. Therapeutic efficacy and immune response induced by Au@Ag₂Se-FA in vitro.

a Cell viability of HUVEC (normal cells) and 4T1 cells (breast carcinoma cells) after incubation with Au@Ag₂Se-FA dispersions at various concentrations for 24 h and 48 h, respectively (n = 6 experimental replicates). b Cell viability of 4T1 cells treated by (i) NIR irradiation only (0.8 W cm^–2, 10 min) (NIR), (ii) Au@Ag₂Se-FA only (100 μg mL^–1) (Au@Ag₂Se-FA), and (iii) Au@Ag₂Se-FA (100 μg mL^–1) combined with NIR irradiation (0.8 W cm^–2, 10 min) (NPs + NIR), with the untreated cells as Control (n = 4 experimental replicates). c Analysis of HSP−70 level in 4T1 cells after treated by Au@Ag₂Se-FA only and NPs+NIR using ELISA (n = 3 experimental replicates). d HMGB1 level in the supernatants of 4T1 cells after various treatments (n = 3 experimental replicates), including (i) 4T1 cells co-cultured with BMDMs for 12 h (Control), (ii) 4T1 cells cultured with Au@Ag₂Se-FA for 12 h and then co-cultured with BMDMs for another 12 h (Au@Ag₂Se-FA), and (iii) 4T1 cells treated by NPs + NIR and then co-cultured with BMDMs for 12 h (NPs+NIR). The relative expression of (e) TNFα, (f), Arg-1, and (g), Fizz1 from M0 macrophages treated with (i) Au@Ag₂Se-FA (100 μg mL^–1) (G1), (ii) PI-Au@Ag₂Se-FA (100 μg mL^–1) (G2), (iii) NIR irradiation only (0.8 W cm^–2, 10 min) (G3), and (iv) Au@Ag₂Se-FA plus NIR irradiation (G4) (n = 3 experimental replicates). Data are presented as mean ± standard deviation. One-way ANOVA with Tukey’s post hoc test. P < 0.05 is considered to be statistically significant. All of these in vitro experiments have been conducted at least three times, yielding well consistent results.