Journal: Journal for Immunotherapy of Cancer

Article Title: Targeting RRBP1 reverses immune evasion and enhances immunotherapy efficacy via the CXCL10-CXCR3 axis in bladder cancer

doi: 10.1136/jitc-2025-013809

Figure Lengend Snippet: Tumor-intrinsic RRBP1 inhibition triggers antitumor immunity. ( A ) Representative images of IHC staining for RRBP1 and CD8 + T cells in BC samples. ( B ) The correlation between RRBP1 expression and CD8 + T-cell infiltration was analyzed based on 96 patients from in-house BC cohort. Scale bar: 50 µm. ( C ) Representative images of IHC staining for RRBP1 expression in PD, SD, PR, and CR samples. Scale bar: 50 µm. ( D ) Bar plot showed the response rates of anti-PD-L1 therapy. Blue bars represent CR/PR, Red bars represent PD/SD. ( E ) Volcano plot of RNA-seq data for shNC or shRRBP1 tumors (n=3). Differentially expressed genes were identified with the threshold of |log2 (fold change) | >1 and FDR<0.05. ( F ) GSEA for DEGs showed the activation of immune-associated pathways in shRRBP1 tumors in the RNA-seq data. ( G ) Representative images of IHC and mIHC staining for RRBP1 and CD8 + T cells in shNC, shRRBP1, control or radezolid tumor tissues. Expression levels of the indicated proteins were displayed. Scale bar: 20 µm. ( H, I ) Flow cytometry showed the percentages of CD8 + T cells in CD3 + cells in shNC, shRRBP1, control or radezolid tumor tissues. Data are represented as mean means±SD. Statistical analysis was performed using Spearman correlation analysis ( B ), unpaired two-tailed t-test ( I ). ****p<0.0001. BC, bladder cancer; CR, complete response; FDR, false discovery rate; progressive disease; PR, partial response; PD-L1, programmed death-ligand 1; RNA-seq, RNA sequencing; RRB1, ribosomal-binding protein 1; SD, stable disease; IHC, immunohistochemistry; GSEA, gene set enrichment analysis; DEGs, differentially expressed genes; mIHC, multiplex immunohistochemistry.

Article Snippet: Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and CD8 + T cells were subsequently enriched using MagCellect Human CD8 + T Cell Isolation Kit (R&D Systems) and the MagCellect Mouse CD8 + T Cell Isolation Kit (R&D Systems) according to the manufacturer’s protocols.

Techniques: Inhibition, Immunohistochemistry, Expressing, RNA Sequencing, Activation Assay, Staining, Control, Flow Cytometry, Two Tailed Test, Binding Assay, Multiplex Assay

Journal: Journal for Immunotherapy of Cancer

Article Title: Targeting RRBP1 reverses immune evasion and enhances immunotherapy efficacy via the CXCL10-CXCR3 axis in bladder cancer

doi: 10.1136/jitc-2025-013809

Figure Lengend Snippet: Single-cell RNA sequencing reveals the difference of CD8 + T-cell subgroup. The UMAP plot of CD8 + T cells subpopulation, color-coded by cell cluster and cell type. ( A ) The expression of markers in each CD8 + T cells subpopulation. ( B ) Bar plot showed the proportion of CD8 + T cells subpopulation in the shNC and shRRBP1 groups. ( C ) The percentage of each CD8 + T-cell clusters in shNC and shRRBP1 groups. ( D ) Heatmap showed the differentially activated pathway among all the CD8 + T-cell clusters. ( E ) The differentially expressed genes in CD8 + T cells between shNC and shRRBP1 groups. ( F ) KEGG analysis for differentially expressed genes showed the enrichment of immune-associated pathways. ( G, H ) mIHC and flow cytometric analysis displayed the tumor-infiltrating IFN-γ + or GZMB + CD8 + T cells in shNC or shRRBP1 tumor tissues. Scale bar: 20 µm. ( I–K ) C57BL/6 mice were subcutaneously injected with 5×10 5 stable MB49 cells (shNC or shRRBP1 cells) (n=6). Isotype control (IgG) or anti-mouse CD8 antibody administered on days –6, –3, and –1 before tumor challenge, with the same dose repeated on days 7, 9 and 11 after tumor challenge. Tumor sizes ( I ), volumes ( J ), and weight ( K ) were measured. Data are represented as mean means±SD. Statistical analysis was performed using unpaired two-tailed t-test ( H, K ) and two-way ANOVA with Tukey’s multiple comparison test ( J ). *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001. ANOVA, analysis of variance; GZMB, Granzyme B; IFN, interferon; TEX, exhausted T cells; UMAP, Uniform Manifold Approximation and Projection; mIHC, multiplex immunohistochemistry; KEGG, Kyoto Encyclopedia of Genes and Genomes.

Article Snippet: Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and CD8 + T cells were subsequently enriched using MagCellect Human CD8 + T Cell Isolation Kit (R&D Systems) and the MagCellect Mouse CD8 + T Cell Isolation Kit (R&D Systems) according to the manufacturer’s protocols.

Techniques: Single Cell, RNA Sequencing, Expressing, Injection, Control, Two Tailed Test, Comparison, Multiplex Assay, Immunohistochemistry

Journal: Journal for Immunotherapy of Cancer

Article Title: Targeting RRBP1 reverses immune evasion and enhances immunotherapy efficacy via the CXCL10-CXCR3 axis in bladder cancer

doi: 10.1136/jitc-2025-013809

Figure Lengend Snippet: RRBP1 inhibition promotes antitumor immunity via the CXCL10-CXCR3 axis in BC. ( A ) ScRNA-seq data showed the CXCR3 expression of CD8+T cells in shNC and shRRBP1 groups. ( B ) The correlation between CXCR3 expression and CXCL10 expression or activated CD8 + T cell based on 571 patients from TCGA-BLCA cohort and GSE13507 cohorts. ( C ) MB49 cells were co-cultured with CD8 + T cells, and tumor cells were stained with crystal violet. ( D ) Evaluation of the effect of genetic inhibition of RRBP1 on the cytotoxicity of CD8 + T cells in vitro conditioned culture model. ( E ) Schematic diagram of in vitro CD8 + T-cell migration assays. ( F ) The number of CD8 + T cells passing through the membrane of a Transwell system was analyzed by flow cytometry. ( G–I ) C57BL/6 mice were subcutaneously injected with 5×10 5 stable MB49 cells (shNC or shRRBP1 cells) (n=6). Tumor-bearing mice received intraperitoneal injection of either vehicle or anti-CXCL10 when the tumor volume reached a calculated average of 100 mm 3 . The tumor sizes ( G ), volumes ( H ), and weights ( I ) were measured. ( J ) Representative images of IHC and mIHC staining for CD8, CXCR3, CXCL10, IFN-γ, GZMB in different tumor tissues. ( K ) Flow cytometric analysis of tumor-infiltrating CD8 + T cells, CXCR3 + CD8 + T cells, IFN-γ + CD8 + T cells or GZMB + CD8 + T cells in distinct tumor tissues. Data are represented as mean means±SD. Statistical analysis was performed using unpaired two-tailed t-test ( D, F, I, K ) and two-way ANOVA with Tukey’s multiple comparison test ( H ). The data presented represent on one or three independent experiments. *p<0.01, **p<0.01, ***p<0.001. ANOVA, analysis of variance; BC, bladder cancer; GZMB, Granzyme B; IFN, interferon; RRBP1, ribosomal-binding protein 1; scRNA-seq, single-cell RNA sequencing; IHC, immunohistochemistry; mIHC, multiplex immunohistochemistry; BLCA, bladder urothelial carcinoma.

Article Snippet: Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and CD8 + T cells were subsequently enriched using MagCellect Human CD8 + T Cell Isolation Kit (R&D Systems) and the MagCellect Mouse CD8 + T Cell Isolation Kit (R&D Systems) according to the manufacturer’s protocols.

Techniques: Inhibition, Expressing, Cell Culture, Staining, In Vitro, Migration, Membrane, Flow Cytometry, Injection, Two Tailed Test, Comparison, Binding Assay, Single Cell, RNA Sequencing, Immunohistochemistry, Multiplex Assay

Journal: Journal for Immunotherapy of Cancer

Article Title: Targeting RRBP1 reverses immune evasion and enhances immunotherapy efficacy via the CXCL10-CXCR3 axis in bladder cancer

doi: 10.1136/jitc-2025-013809

Figure Lengend Snippet: RRBP1 inhibition enhances response to anti-PD-L1 therapy in BC. ( A–D ) The protein expression of surface PD-L1 was analyzed in BC cells or tumor tissues by flow cytometry after RRBP1 inhibition and was shown as the mean fluorescence intensity. ( E–G ) C57BL/6 mice were subcutaneously injected with 5×10 5 stable MB49 cells (shNC or shRRBP1 cells) (n=6). Tumor-bearing mice were received intraperitoneal injection of either vehicle or anti-PD-L1 antibody when the tumor volume reached a calculated average of 100 mm 3 . The tumor sizes ( E ), volumes ( F ), and weights ( G ) were measured. ( H ) Representative images of IHC and mIHC staining for CD8, CXCR3, CXCL10, IFN-γ, GZMB in different tumor tissues. ( I ) Flow cytometric analysis of tumor-infiltrating CD8 + T cells, CXCR3 + CD8 + T cells, IFN-γ + CD8 + T cells or GZMB + CD8 + T cells in distinct tumor tissues. Data are represented as mean means±SD. Statistical analysis was performed using unpaired two-tailed t-test ( B, D, G, I ) and two-way ANOVA with Tukey’s multiple comparison test ( F ). The data presented represent on one or three independent experiments. *p<0.01, **p<0.01, ***p<0.001. ANOVA, analysis of variance; BC, bladder cancer; GZMB, Granzyme B; IFN, interferon; PD-L1, programmed death-ligand 1; RRBP1, ribosomal-binding protein 1; IHC, immunohistochemistry; mIHC, multiplex immunohistochemistry.

Article Snippet: Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and CD8 + T cells were subsequently enriched using MagCellect Human CD8 + T Cell Isolation Kit (R&D Systems) and the MagCellect Mouse CD8 + T Cell Isolation Kit (R&D Systems) according to the manufacturer’s protocols.

Techniques: Inhibition, Expressing, Flow Cytometry, Fluorescence, Injection, Staining, Two Tailed Test, Comparison, Binding Assay, Immunohistochemistry, Multiplex Assay

Journal: Journal for Immunotherapy of Cancer

Article Title: Targeting RRBP1 reverses immune evasion and enhances immunotherapy efficacy via the CXCL10-CXCR3 axis in bladder cancer

doi: 10.1136/jitc-2025-013809

Figure Lengend Snippet: Tumor-intrinsic RRBP1 inhibition triggers antitumor immunity. ( A ) Representative images of IHC staining for RRBP1 and CD8 + T cells in BC samples. ( B ) The correlation between RRBP1 expression and CD8 + T-cell infiltration was analyzed based on 96 patients from in-house BC cohort. Scale bar: 50 µm. ( C ) Representative images of IHC staining for RRBP1 expression in PD, SD, PR, and CR samples. Scale bar: 50 µm. ( D ) Bar plot showed the response rates of anti-PD-L1 therapy. Blue bars represent CR/PR, Red bars represent PD/SD. ( E ) Volcano plot of RNA-seq data for shNC or shRRBP1 tumors (n=3). Differentially expressed genes were identified with the threshold of |log2 (fold change) | >1 and FDR<0.05. ( F ) GSEA for DEGs showed the activation of immune-associated pathways in shRRBP1 tumors in the RNA-seq data. ( G ) Representative images of IHC and mIHC staining for RRBP1 and CD8 + T cells in shNC, shRRBP1, control or radezolid tumor tissues. Expression levels of the indicated proteins were displayed. Scale bar: 20 µm. ( H, I ) Flow cytometry showed the percentages of CD8 + T cells in CD3 + cells in shNC, shRRBP1, control or radezolid tumor tissues. Data are represented as mean means±SD. Statistical analysis was performed using Spearman correlation analysis ( B ), unpaired two-tailed t-test ( I ). ****p<0.0001. BC, bladder cancer; CR, complete response; FDR, false discovery rate; progressive disease; PR, partial response; PD-L1, programmed death-ligand 1; RNA-seq, RNA sequencing; RRB1, ribosomal-binding protein 1; SD, stable disease; IHC, immunohistochemistry; GSEA, gene set enrichment analysis; DEGs, differentially expressed genes; mIHC, multiplex immunohistochemistry.

Article Snippet: Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and CD8 + T cells were subsequently enriched using MagCellect Human CD8 + T Cell Isolation Kit (R&D Systems) and the MagCellect Mouse CD8 + T Cell Isolation Kit (R&D Systems) according to the manufacturer’s protocols.

Techniques: Inhibition, Immunohistochemistry, Expressing, RNA Sequencing, Activation Assay, Staining, Control, Flow Cytometry, Two Tailed Test, Binding Assay, Multiplex Assay

Journal: Journal for Immunotherapy of Cancer

Article Title: Targeting RRBP1 reverses immune evasion and enhances immunotherapy efficacy via the CXCL10-CXCR3 axis in bladder cancer

doi: 10.1136/jitc-2025-013809

Figure Lengend Snippet: Single-cell RNA sequencing reveals the difference of CD8 + T-cell subgroup. The UMAP plot of CD8 + T cells subpopulation, color-coded by cell cluster and cell type. ( A ) The expression of markers in each CD8 + T cells subpopulation. ( B ) Bar plot showed the proportion of CD8 + T cells subpopulation in the shNC and shRRBP1 groups. ( C ) The percentage of each CD8 + T-cell clusters in shNC and shRRBP1 groups. ( D ) Heatmap showed the differentially activated pathway among all the CD8 + T-cell clusters. ( E ) The differentially expressed genes in CD8 + T cells between shNC and shRRBP1 groups. ( F ) KEGG analysis for differentially expressed genes showed the enrichment of immune-associated pathways. ( G, H ) mIHC and flow cytometric analysis displayed the tumor-infiltrating IFN-γ + or GZMB + CD8 + T cells in shNC or shRRBP1 tumor tissues. Scale bar: 20 µm. ( I–K ) C57BL/6 mice were subcutaneously injected with 5×10 5 stable MB49 cells (shNC or shRRBP1 cells) (n=6). Isotype control (IgG) or anti-mouse CD8 antibody administered on days –6, –3, and –1 before tumor challenge, with the same dose repeated on days 7, 9 and 11 after tumor challenge. Tumor sizes ( I ), volumes ( J ), and weight ( K ) were measured. Data are represented as mean means±SD. Statistical analysis was performed using unpaired two-tailed t-test ( H, K ) and two-way ANOVA with Tukey’s multiple comparison test ( J ). *p<0.05, **p<0.01, ***p<0.001, ****p<0.0001. ANOVA, analysis of variance; GZMB, Granzyme B; IFN, interferon; TEX, exhausted T cells; UMAP, Uniform Manifold Approximation and Projection; mIHC, multiplex immunohistochemistry; KEGG, Kyoto Encyclopedia of Genes and Genomes.

Article Snippet: Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and CD8 + T cells were subsequently enriched using MagCellect Human CD8 + T Cell Isolation Kit (R&D Systems) and the MagCellect Mouse CD8 + T Cell Isolation Kit (R&D Systems) according to the manufacturer’s protocols.

Techniques: Single Cell, RNA Sequencing, Expressing, Injection, Control, Two Tailed Test, Comparison, Multiplex Assay, Immunohistochemistry

Journal: Journal for Immunotherapy of Cancer

Article Title: Targeting RRBP1 reverses immune evasion and enhances immunotherapy efficacy via the CXCL10-CXCR3 axis in bladder cancer

doi: 10.1136/jitc-2025-013809

Figure Lengend Snippet: RRBP1 inhibition promotes antitumor immunity via the CXCL10-CXCR3 axis in BC. ( A ) ScRNA-seq data showed the CXCR3 expression of CD8+T cells in shNC and shRRBP1 groups. ( B ) The correlation between CXCR3 expression and CXCL10 expression or activated CD8 + T cell based on 571 patients from TCGA-BLCA cohort and GSE13507 cohorts. ( C ) MB49 cells were co-cultured with CD8 + T cells, and tumor cells were stained with crystal violet. ( D ) Evaluation of the effect of genetic inhibition of RRBP1 on the cytotoxicity of CD8 + T cells in vitro conditioned culture model. ( E ) Schematic diagram of in vitro CD8 + T-cell migration assays. ( F ) The number of CD8 + T cells passing through the membrane of a Transwell system was analyzed by flow cytometry. ( G–I ) C57BL/6 mice were subcutaneously injected with 5×10 5 stable MB49 cells (shNC or shRRBP1 cells) (n=6). Tumor-bearing mice received intraperitoneal injection of either vehicle or anti-CXCL10 when the tumor volume reached a calculated average of 100 mm 3 . The tumor sizes ( G ), volumes ( H ), and weights ( I ) were measured. ( J ) Representative images of IHC and mIHC staining for CD8, CXCR3, CXCL10, IFN-γ, GZMB in different tumor tissues. ( K ) Flow cytometric analysis of tumor-infiltrating CD8 + T cells, CXCR3 + CD8 + T cells, IFN-γ + CD8 + T cells or GZMB + CD8 + T cells in distinct tumor tissues. Data are represented as mean means±SD. Statistical analysis was performed using unpaired two-tailed t-test ( D, F, I, K ) and two-way ANOVA with Tukey’s multiple comparison test ( H ). The data presented represent on one or three independent experiments. *p<0.01, **p<0.01, ***p<0.001. ANOVA, analysis of variance; BC, bladder cancer; GZMB, Granzyme B; IFN, interferon; RRBP1, ribosomal-binding protein 1; scRNA-seq, single-cell RNA sequencing; IHC, immunohistochemistry; mIHC, multiplex immunohistochemistry; BLCA, bladder urothelial carcinoma.

Article Snippet: Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and CD8 + T cells were subsequently enriched using MagCellect Human CD8 + T Cell Isolation Kit (R&D Systems) and the MagCellect Mouse CD8 + T Cell Isolation Kit (R&D Systems) according to the manufacturer’s protocols.

Techniques: Inhibition, Expressing, Cell Culture, Staining, In Vitro, Migration, Membrane, Flow Cytometry, Injection, Two Tailed Test, Comparison, Binding Assay, Single Cell, RNA Sequencing, Immunohistochemistry, Multiplex Assay

Journal: Journal for Immunotherapy of Cancer

Article Title: Targeting RRBP1 reverses immune evasion and enhances immunotherapy efficacy via the CXCL10-CXCR3 axis in bladder cancer

doi: 10.1136/jitc-2025-013809

Figure Lengend Snippet: RRBP1 inhibition enhances response to anti-PD-L1 therapy in BC. ( A–D ) The protein expression of surface PD-L1 was analyzed in BC cells or tumor tissues by flow cytometry after RRBP1 inhibition and was shown as the mean fluorescence intensity. ( E–G ) C57BL/6 mice were subcutaneously injected with 5×10 5 stable MB49 cells (shNC or shRRBP1 cells) (n=6). Tumor-bearing mice were received intraperitoneal injection of either vehicle or anti-PD-L1 antibody when the tumor volume reached a calculated average of 100 mm 3 . The tumor sizes ( E ), volumes ( F ), and weights ( G ) were measured. ( H ) Representative images of IHC and mIHC staining for CD8, CXCR3, CXCL10, IFN-γ, GZMB in different tumor tissues. ( I ) Flow cytometric analysis of tumor-infiltrating CD8 + T cells, CXCR3 + CD8 + T cells, IFN-γ + CD8 + T cells or GZMB + CD8 + T cells in distinct tumor tissues. Data are represented as mean means±SD. Statistical analysis was performed using unpaired two-tailed t-test ( B, D, G, I ) and two-way ANOVA with Tukey’s multiple comparison test ( F ). The data presented represent on one or three independent experiments. *p<0.01, **p<0.01, ***p<0.001. ANOVA, analysis of variance; BC, bladder cancer; GZMB, Granzyme B; IFN, interferon; PD-L1, programmed death-ligand 1; RRBP1, ribosomal-binding protein 1; IHC, immunohistochemistry; mIHC, multiplex immunohistochemistry.

Article Snippet: Peripheral blood mononuclear cells were isolated by Ficoll density gradient centrifugation, and CD8 + T cells were subsequently enriched using MagCellect Human CD8 + T Cell Isolation Kit (R&D Systems) and the MagCellect Mouse CD8 + T Cell Isolation Kit (R&D Systems) according to the manufacturer’s protocols.

Techniques: Inhibition, Expressing, Flow Cytometry, Fluorescence, Injection, Staining, Two Tailed Test, Comparison, Binding Assay, Immunohistochemistry, Multiplex Assay

Journal: bioRxiv

Article Title: Munc13-4 mediates tumor immune evasion by regulating the sorting and secretion of PD-L1 via exosomes

doi: 10.1101/2025.03.22.644518

Figure Lengend Snippet: Munc13-4 deficiency in tumor cells enhances T cell infiltration and activation (A–C) Flow cytometric quantification of the percentage of CD45 + CD3 + CD4 + and CD45 + CD3 + CD8 + T cells among total cells in the tumors (A) , spleens (B) , and draining lymph nodes (C) of BALB/c mice (n = 5), 21 days after mammary gland injection with 3 × 10 5 control or Munc13-4 KO 4T1 cells per mouse. (D–F) Quantification of the percentage of granzyme B + (GzmB + ) (D) , Ki67 + (E) and IFNγ + (F) cells among CD45 + CD3 + CD4 + and CD45 + CD3 + CD8 + T cells within tumors from orthotopic mouse models of breast cancer generated by control or Munc13-4 KO 4T1 cells (n = 5). (G–I) Quantification of the percentage of granzyme B + (G) , Ki67 + (H) and IFNγ + (I) cells among CD45 + CD3 + CD4 + and CD45 + CD3 + CD8 + T cells within spleens from orthotopic mouse models of breast cancer generated by control or Munc13-4 KO 4T1 cells (n = 5). (J–L) Quantification of the percentage of granzyme B + (J) , Ki67 + (K) and IFNγ + (L) cells among CD45 + CD3 + CD4 + and CD45 + CD3 + CD8 + T cells within the draining lymph nodes from orthotopic mouse models of breast cancer generated by control or Munc13-4 KO 4T1 cells (n = 5). Box plots show all data points, all p -values were calculated by Multiple t tests. See also Figure S3.

Article Snippet: Mouse CD8 + T cells were purified from splenocytes using the Mouse CD8 T Cell Isolation Kit (Vazyme, CS103-01) and stimulated for 24 hours with anti-CD3 (Biolegend, 300301, 1 μg/ml) and anti-CD28 (Biolegend, 117003, 1 μg/ml) antibodies.

Techniques: Activation Assay, Injection, Control, Generated

Journal: bioRxiv

Article Title: Munc13-4 mediates tumor immune evasion by regulating the sorting and secretion of PD-L1 via exosomes

doi: 10.1101/2025.03.22.644518

Figure Lengend Snippet: A peptide disrupting PD-L1 – Munc13-4 interaction inhibits tumor growth (A) Prediction of the interaction between PD-L1 (residues 253–290) and Munc13-4 (residues 1049–1080). Top insets show five ensembles generated by AlphaFold multimer, where N- and C-terminus of the proteins are indicated. PD-L1 and Munc13-4 are colored in blue and red, respectively. Residues that show potential contacts with each other (within 4 Å) are shown in sticks. Bottom inset displays the statistics of the residues in PD-L1 that show contacts with Munc13-4. The absolute and averaged contact numbers for each ensemble are illustrated by stacked histograms and line-scatter plot. The potential Munc13-4–interacting sequence of PD-L1 is shaded in magenta. (B) Diagram of the sequences for P-pep and S-pep. P-pep comprises a cell-penetrating peptide (CPP) fused to the human PD-L1 256–273 motif, whereas S-pep consists of a CPP linked to a scrambled sequence containing the same amino acid composition as the human PD-L1 256–273 motif. (C) Co-IP and IB analysis in HEK293T cells transfected with indicated constructs and incubated with P-pep or S-pep to examine the effect of P-pep on Munc13-4–PD-L1 interaction (n = 3). (D) Co-IP and IB analysis in HEK293T cells transfected with indicated constructs and incubated with P-pep or S-pep to assess the effect of P-pep on the interactions of HRS with PD-L1 and Munc13-4 (n = 3). (E) Western blot analysis of PD-L1, Alix, CD63 and CD81 abundance on the same number of exosomes secreted from equal number of SUM159 cells treated with S-pep or P-pep. (F and G) Assessment of in vivo anti-tumor efficacy of P-pep. (F) Schematic of experimental design. (G) Tumor growth curves of orthotopic mouse models of breast cancer treated with P-pep or S-pep (n = 9). (H and I) Flow cytometric quantification of the percentage of CD45 + CD3 + CD4 + (H) and CD45 + CD3 + CD8 + (I) T cells among total cells in tumors (n = 5). (J and L) Representative contour plots depicting CD45 + CD3 + CD4 + (J) and CD45 + CD3 + CD8 + (L) T cell populations within tumors, showing the expression of granzyme B. (K and M) Quantification of the percentage of granzyme B + cells among CD45 + CD3 + CD4 + (K) and CD45 + CD3 + CD8 + (M) T cells within tumors (n = 5). Data are represented as means ± SEM (G), box plots show all data points (H, I, K and M), p -values were all calculated by unpaired t test. See also Figure S12.

Article Snippet: Mouse CD8 + T cells were purified from splenocytes using the Mouse CD8 T Cell Isolation Kit (Vazyme, CS103-01) and stimulated for 24 hours with anti-CD3 (Biolegend, 300301, 1 μg/ml) and anti-CD28 (Biolegend, 117003, 1 μg/ml) antibodies.

Techniques: Generated, Sequencing, Co-Immunoprecipitation Assay, Transfection, Construct, Incubation, Western Blot, In Vivo, Expressing