z ietd fmk  (R&D Systems)

Journal: iScience

Article Title: Antigen-directed single domain antibody-based TNFR1 agonists elicit preferential killing of HER2-overexpressing cancer cells

doi: 10.1016/j.isci.2026.115327

Figure Lengend Snippet: HER2-targeted TNFR1-agonists induce TNF-like caspase-1, caspase-3, and caspase-8 activation decoupled from NF-κB signaling in MCF-7 cells (A–C) Caspase-1/3/8 activation of HER2-expressing MCF-7 cells by ICM11 derivatives compared to (rh)TNF. MCF-7 cells were stimulated with increasing compound concentrations for 72 h. Caspase activities were detected intracellularly with FAM-FLICA(R) Caspase 1 Assay Kit (Biomol), CaspaTag Caspase-3 In situ Assay Kit (Merck Millipore), and CaspaTag Caspase-8 In Situ Assay Kit (Merck Millipore). Caspase-1/3/8 activation was normalized to (rh) TNF. (D) NF-κB activation in MCF-7 cells triggered by ICM11 derivatives and (rh) TNF. MCF-7 cells were stimulated with increasing concentrations of ICMs and (rh) TNF for 40 min. NF-κB was stained intracellularly with AF488-labeled anti-NF-κB staining antibody (BD) after lysis, fixation, and permeabilization of cells. (E) Remaining relative cell death of MCF-7 cells after treatment with ICM11 derivatives or (rh)TNF in the presence or absence of caspase inhibitors. MCF-7 cells were incubated with caspase-1 inhibitor (InvivoGen), caspase-3 inhibitor (R&D Systems), caspase-8 inhibitor (InvivoGen), or pan-caspase inhibitor (InvivoGen) at 50 μM and a fixed (rh) TNF or ICM concentration of 5 nM for 72 h. Killing was monitored by green fluorescence signal with SYTOX Green Dead Cell Stain and normalized to (rh) TNF signal. Mean values ±SEM of four independent experiments for each figure are shown. ∗∗∗∗ p < 0.0001,∗∗∗ p < 0.001, ∗∗ p < 0.01, and ∗ p < 0.05 calculated by utilizing two-way ANOVA multiple analyses and Bonferroni test.

Article Snippet: We also set out to investigate the consequences of caspase inhibition on cell death induction, harnessing caspase-1 inhibitor (Ac-YVAD-cmk, InvivoGen), caspase-3 inhibitor (Z-DEVD-FMK, R&D Systems), and caspase-8 inhibitor (Z-IETD-FMK, InvivoGen) as well as pan-caspase inhibitor (zVAD-FMK, InvivoGen).

Techniques: Activation Assay, Expressing, In Situ, Staining, Labeling, Lysis, Incubation, Concentration Assay, Fluorescence

Journal: iScience

Article Title: Antigen-directed single domain antibody-based TNFR1 agonists elicit preferential killing of HER2-overexpressing cancer cells

doi: 10.1016/j.isci.2026.115327

Figure Lengend Snippet: HER2-targeted TNFR1-agonists induce TNF-like caspase-1, caspase-3, and caspase-8 activation decoupled from NF-κB signaling in MCF-7 cells (A–C) Caspase-1/3/8 activation of HER2-expressing MCF-7 cells by ICM11 derivatives compared to (rh)TNF. MCF-7 cells were stimulated with increasing compound concentrations for 72 h. Caspase activities were detected intracellularly with FAM-FLICA(R) Caspase 1 Assay Kit (Biomol), CaspaTag Caspase-3 In situ Assay Kit (Merck Millipore), and CaspaTag Caspase-8 In Situ Assay Kit (Merck Millipore). Caspase-1/3/8 activation was normalized to (rh) TNF. (D) NF-κB activation in MCF-7 cells triggered by ICM11 derivatives and (rh) TNF. MCF-7 cells were stimulated with increasing concentrations of ICMs and (rh) TNF for 40 min. NF-κB was stained intracellularly with AF488-labeled anti-NF-κB staining antibody (BD) after lysis, fixation, and permeabilization of cells. (E) Remaining relative cell death of MCF-7 cells after treatment with ICM11 derivatives or (rh)TNF in the presence or absence of caspase inhibitors. MCF-7 cells were incubated with caspase-1 inhibitor (InvivoGen), caspase-3 inhibitor (R&D Systems), caspase-8 inhibitor (InvivoGen), or pan-caspase inhibitor (InvivoGen) at 50 μM and a fixed (rh) TNF or ICM concentration of 5 nM for 72 h. Killing was monitored by green fluorescence signal with SYTOX Green Dead Cell Stain and normalized to (rh) TNF signal. Mean values ±SEM of four independent experiments for each figure are shown. ∗∗∗∗ p < 0.0001,∗∗∗ p < 0.001, ∗∗ p < 0.01, and ∗ p < 0.05 calculated by utilizing two-way ANOVA multiple analyses and Bonferroni test.

Article Snippet: We also set out to investigate the consequences of caspase inhibition on cell death induction, harnessing caspase-1 inhibitor (Ac-YVAD-cmk, InvivoGen), caspase-3 inhibitor (Z-DEVD-FMK, R&D Systems), and caspase-8 inhibitor (Z-IETD-FMK, InvivoGen) as well as pan-caspase inhibitor (zVAD-FMK, InvivoGen).

Techniques: Activation Assay, Expressing, In Situ, Staining, Labeling, Lysis, Incubation, Concentration Assay, Fluorescence