Extended Data Fig. 2: Early endosome stress of PEPA nanophotosensitizer evokes GSDME-mediated pyroptosis in murine tumor cells.
From: In situ-generated vaccine-like pyroptosome for personalized cancer immunotherapy
(a) Confocal images of intracellular singlet oxygen generation measured by SOSG nanoprobe (nSOSG, green) and colocalization with PEPA and endocytic organelles at 0.5 h (Rab5a, early endosome marker, blue) and 2 h (Lamp1, lysosome marker, blue) post-internalization. The green signal of nSOSG indicates singlet oxygen generated by PEPA nanophotosensitizer after 660 nm irradiation. Scale bar = 10 μm. (b) Representative phase-contrast images of cell death morphology induced by PEPAEE or PEPALy on CT26 and CT26-GSDME−/− cells. Scale bar = 20 μm. (c) MTT assay and LDH release assay of PEPAEE stress on CT26 and CT26-GSDME−/− cells. GSDME knockout rescued EE stress-induced pyroptosis. Data are presented as mean ± s.d. (n = 3 biologically independent experiments). Statistical significance was analyzed by two-sided Student’s t-test. (d) Immunoblots of endogenous GSDME expression in different murine cancer cell lines. (e) Heatmap of GSDME expression quantified from panel d. (f) Photocytotoxicity of PEPAEE or PEPALy on different murine cancer cell lines. Data are presented as mean ± s.d. (n = 3 biologically independent experiments). (g) Phase-contrast imaging of cell death morphology on different murine cancer cells treated with PEPA6.5-mediated EE stress. Scale bar = 20 μm.
