Fig. 3

The NIR-II activated BPSP partially reduced collagen I in ECM, thus improving deep penetration, and inducing the ICD effect. a Schematic diagram of NIR-II activated BPSP could lead to a decrease in collagen I and promote deep penetration. b The expression level of collagen I in Hepa1-6 subcutaneous tumors treated with different groups. c Deep penetration of different groups in Hepa1-6 tumor spheroids characterized by confocal microscopy (scale bar: 200 μm). d Tumor tissue section after administrated of C6, BPC, and BPCP at 12 h (scale bar: 1000 μm). e Schematic diagram of photothermal imaging in the mice with the 5 mm pigskin. f Photothermal imaging of the mice between different groups with and without 5 mm pigskin by infrared thermal imaging, recorded at 0, 60, 180, and 300 s with NIR-II laser irradiation 12 h post-injection of NS, BPNSs, BP@PEG, BPS, and BPSP. g Fluorescence microscopy images of calreticulin (CRT) exposure in Hepa1-6 cells incubated with the different groups. h Fluorescence microscopy images of homo mobility group box 1 (HMGB1) exposure in Hepa1-6 cells. i Quantitative analysis of CRT expression capability in Hepa1-6 cells incubated with the different groups by flow cytometry. j Enzyme-linked immunosorbent assay (ELISA) detection of HMGB1 after treatment with the different groups in Hepa1-6 cells. k ATP secretion from Hepa1-6 cells. l, m DC maturation was analyzed by FCM in Hepa1-6 tumor-bearing mice. Data represented mean ± SD (n = 3). *p < 0.05, **p < 0.01, ***p < 0.001