Fig 2: SH3BGRL3 regulates exosome release and immune escape in TNBC mice through Rab27a. A: Transmission electron microscopy observation of exosomes, scale bar: 100 nm; B: NTA of exosome particle concentration and size distribution; C: Western blot analysis of exosome marker proteins CD63, Alix, and TSG101; D-F: Flow cytometric analysis of the percentage of PD‑1⁺, TIM‑3⁺, LAG‑3⁺ cells within the CD3⁺CD8⁺ T‑cell population isolated from tumor tissues of different treatment groups; G: Immunofluorescence co‑localization analysis of PD‑1 expression in CD8⁺ T cells. **P < 0.01, *** P < 0.001