cd8 antibody  (NSJ Bioreagents)

Journal: Science Advances

Article Title: CREBBP loss drives immune evasion by epigenetically silencing STING and MHC-I in small cell lung cancer

doi: 10.1126/sciadv.aef1693

Figure Lengend Snippet: ( A ) In vivo tumor growth of RP-sgCtrl and RP-sg Crebbp cells in nude mice, with quantification of tumor weights at the endpoint (n = 6 per group). ( B ) In vivo tumor growth of RP-sgCtrl and RP-sg Crebbp cells in C57BL/6 mice, with quantification of tumor weights at the endpoint (n = 6 per group). ( C ) In vivo tumor growth of RP-shCtrl and RP-sh Crebbp cells in nude mice, with quantification of tumor weights at the endpoint (n = 5 per group). ( D ) In vivo tumor growth of RP-shCtrl and RP-sh Crebbp cells in C57BL/6 mice, with quantification of tumor weights at the endpoint (n = 4 for RP-shNS, n = 5 for each RP-sh Crebbp cell). ( E to G ) Flow cytometry analysis of CD8 + T cell proportions (E), CD44 hi CD62L lo CD8+ T cell proportions (F), and IFNγ + CD8 + T cell proportions (G) in allograft tumors formed by RP-sgCtrl and RP-sg Crebbp cells in C57BL/6 mice. n = 6 per group. ( H ) In vivo growth of RP-sgCtrl and RP-sg Crebbp cells in C57BL/6 mice treated with IgG control or anti-CD8 antibodies, with quantification of tumor weights at the endpoint (n = 5 per group). ( I ) Flow cytometry analysis of apoptotic RP-OVA, RP-OVA-shCtrl, and RP-OVA-sh Crebbp -1 tumor cells, with or without co-culture with OT-1 CD8 + T cells. Quantification of the apoptotic tumor cell proportions is shown (right). [(A), (B), (C), (D), and (H)] Two-way ANOVA test for tumor growth curves and unpaired Student’s t test for tumor weights. *** P < 0.001; **** P < 0.0001. ns, not significant. Data were shown as mean ± SEM. [(E) to (G) and (I)] Unpaired Student’s t test; * P < 0.05; ** P < 0.01. Data were shown as mean ± SD.

Article Snippet: For CD8 + T cell blockade experiments, IgG1 isotype control (BE0088, Bio X Cell, RRID: AB_1107775) and anti-CD8 (BE0223, Bio X Cell, RRID: AB_2687706) antibodies were administered intraperitoneally at 100 μg per mouse one day before tumor cell inoculation, followed by a second dose immediately after cell injection, and then doses every 3 days.

Techniques: In Vivo, Flow Cytometry, Analysis, Control, Co-culture Assay, shRNA

Journal: Journal for Immunotherapy of Cancer

Article Title: Engineering T cell-engaging bispecific antibodies targeting KRAS G12V neoantigen across HLA-A*11:01 and HLA-A*03:01

doi: 10.1136/jitc-2026-016411

Figure Lengend Snippet: Characterization of KRAS G12V-BsAb. ( A–B ) Selective binding of the purified scDb2 to KRAS G12V/HLA-A*11:01 ( A ) and CD3 ( B ) by ELISA. Biotinylated KRAS G12V/HLA-A*11:01 or recombinant CD3ε/δ was coated on a streptavidin plate and then incubated with scDb2 at 0.1, 1 or 10 nM, followed by detection with an anti-His antibody. Optical density at 450 nm was measured on a spectrophotometric plate reader. Data represent mean±SD of three technical replicates. ( C ) Surface plasmon resonance analysis of scDb2 binding to KRAS G12V/HLA-A*11:01 and KRAS WT/HLA-A*11:01. Binding kinetics were determined by fitting to a 1:1 Langmuir model. ( D ) Dose-dependent T-cell activation by scDb2. C1R-A11 cells pulsed with KRAS G12V or WT peptides were co-cultured with CD8 + T cells in the presence of increasing concentrations (0, 0.1, 0.3, 1 and 10 nM) of scDb2. IFN-γ secretion was quantified by ELISpot assay. Data represent mean±SD of three technical replicates. The EC 50 for IFN-γ secretion was 0.59 nM for C1R-A11 cells. p=0.0023 at 0.3 nM and p<0.0001 at 1 and 10 nM versus KRAS WT (Tukey’s test). ( E ) KRAS peptide-specific T-cell activation by scDb2. C1R-A11 cells were pulsed with different KRAS G12 variant peptides (WT, G12A, G12C, G12D, G12R and G12S), then co-cultured with CD8 + T cells in the presence of 1 nM KRAS G12V/A11:01-specific scDb2. IFN-γ secretion was measured by ELISpot. Data represent mean±SD of three technical replicates. p<0.0001 versus no peptide (Dunnett’s test). ( F ) HLA-restricted T-cell activation by scDb2. C1R cells expressing a panel of prevalent HLA-A alleles (HLA-A*02:01, HLA-A*02:06, HLA-A*03:01, HLA-A*11:01, HLA-A*24:02, HLA-A*31:01 and HLA-A*33:03) were pulsed with KRAS G12V peptide and co-cultured with CD8 + T cells in the presence of 1 nM KRAS G12V/A11:01-specific scDb2. Data represent mean±SD of three technical replicates. p<0.0001 for HLA-A*11:01 and HLA-A*03:01 versus the no-peptide control; no significant differences were observed for the other HLA alleles versus the no-peptide control (Dunnett’s test). BsAb, bispecific antibody; EC 50 , half-maximal effective concentrations; ELISpot, enzyme-linked immunosorbent spot; HLA, human leukocyte antigen; IFN, interferon; scDb, single-chain diabody; WT, wild-type.

Article Snippet: Sections were then incubated with primary antibodies: anti-CD8 mouse monoclonal antibody (Proteintech, Rosemont, Illinois, USA) and anti-Ki67 rabbit monoclonal antibody (Cell Signaling Technology, Danvers, Massachusetts, USA).

Techniques: Binding Assay, Purification, Enzyme-linked Immunosorbent Assay, Recombinant, Incubation, SPR Assay, Analysis, Activation Assay, Cell Culture, Enzyme-linked Immunospot, Variant Assay, Expressing, Control, ELISpot Assay

Journal: Journal for Immunotherapy of Cancer

Article Title: Engineering T cell-engaging bispecific antibodies targeting KRAS G12V neoantigen across HLA-A*11:01 and HLA-A*03:01

doi: 10.1136/jitc-2026-016411

Figure Lengend Snippet: Assessment of KRAS G12V/A*11:01-specific scDb2 specificity and potential cross-reactivity. ( A ) Cross-reactivity of KRAS G12V variant peptides. C1R-A11 cells were pulsed with the parental KRAS G12V peptide or amino acid-substituted variants, and co-cultured with CD8 + T cells in the presence of 1 nM KRAS G12V/A*11:01-specific scDb2. IFN-γ release was measured by ELISpot assay, and the mean of duplicate wells was used to generate the heatmap. Black boxes indicate the amino acids present in the parental G12V peptide. ( B ) Sequence specificity of KRAS G12V/A*11:01 scDb2 visualized as a Seq2Logo plot. Values were calculated by normalizing IFN-γ signals to a constant and plotting using the R package Seq2Logo. ( C ) AlphaFold-predicted structure of the KRAS G12V-scFv2 in complex with KRAS G12V/HLA-A*11:01. HLA-A*11:01, scFv and β2 microglobulin (β2M) are colored in gray, wheat and cyan, respectively. The KRAS G12V peptide is shown in light red between helices α1 and α2 of the HLA. ( D ) Bird’s-eye view of surface representation of the HLA-A*11:01 shown in gray, KRAS G12V peptide shown in red, and the contacting residues colored according to complementarity-determining regions (CDRs) of the scFv. The CDRs are labeled and colored as: H3 (pink), H2 (purple), H1 (sky blue), L3 (green), L2 (limon), L1 (dark green). ELISpot, enzyme-linked immunosorbent spot; HLA, human leukocyte antigen; IFN, interferon; scDb, single-chain diabody; scFv, single-chain variable fragments; WT, wild-type.

Article Snippet: Sections were then incubated with primary antibodies: anti-CD8 mouse monoclonal antibody (Proteintech, Rosemont, Illinois, USA) and anti-Ki67 rabbit monoclonal antibody (Cell Signaling Technology, Danvers, Massachusetts, USA).

Techniques: Variant Assay, Cell Culture, Enzyme-linked Immunospot, Sequencing, Labeling, ELISpot Assay

Journal: Journal for Immunotherapy of Cancer

Article Title: Engineering T cell-engaging bispecific antibodies targeting KRAS G12V neoantigen across HLA-A*11:01 and HLA-A*03:01

doi: 10.1136/jitc-2026-016411

Figure Lengend Snippet: In vivo antitumor efficacy of KRAS G12V-specific scDb2. ( A ) NSG mice were engrafted through s.c. injection with 5×10 6 SNG-M cells on day −7. On day 0, mice were randomized based on tumor sizes, and 2×10 7 human PBMCs or PBS as a vehicle control, and KRAS G12V-specific scDb2 or isotype control scDb (10 µg/mouse) were injected i.p. scDbs were subsequently injected two times per week. ( B ) Tumor progression was monitored by measuring tumor size. Data represent mean±SEM (n=8 mice/group). *p=0.043 PBMC+KRAS scDb2 versus PBMC+isotype scDb at the last time point (Tukey’s test). ( C ) Tumor weight of each mouse at the end of experiment was measured. Boxes show the median and IQR with individual mice plotted (n=8 mice/group). p values were calculated by Tukey’s test. ( D ) Representative H&E and multiplex immunohistochemical staining for CD8 and Ki67. Scale bars, 50 µm. ( E ) Proportion of CD8 + T cells and Ki67 + proliferating CD8 + T cells in tumors from each group. Data represent mean±SD (n=8 mice/group). p values were calculated by Tukey’s test. Scale bars, 10 µm. ( F ) Body weights of the mice were serially monitored in the established SNG-M model. Data represent mean±SEM (n=8 mice/group). (Tukey’s test, p=0.88 at the last time point). ( G ) Representative H&E staining of kidney and liver tissues from mice across treatment groups. Scale bars, 50 µm. i.p., intraperitoneally; NS, not significant; PBMC, peripheral blood mononuclear cells; PBS, phosphate buffered saline; s.c., subcutaneous; scDb, single-chain diabody.

Article Snippet: Sections were then incubated with primary antibodies: anti-CD8 mouse monoclonal antibody (Proteintech, Rosemont, Illinois, USA) and anti-Ki67 rabbit monoclonal antibody (Cell Signaling Technology, Danvers, Massachusetts, USA).

Techniques: In Vivo, Injection, Control, Multiplex Assay, Immunohistochemical staining, Staining, Saline