The DPP9 Knockout AGS Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the human gastric adenocarcinoma AGS cell line, with targeted disruption of the DPP9 gene encoding dipeptidyl peptidase 9. This polyclonal pool provides a heterogeneous loss-of-function model that lacks DPP9 protease activity across a mixed cell population, enabling robust examination of DPP9-dependent cellular processes without clonal bias. The knockout model is generated via CRISPR/Cas9-mediated gene disruption, resulting in ablation of DPP9 function and consequent relief of inflammasome autoinhibition.
The parental AGS cell line originates from a human gastric adenocarcinoma and is widely employed as an epithelial model for gastric cancer research. These cells retain key characteristics of gastric adenocarcinoma, including aberrant signaling pathways, making them suitable for investigating cancer-associated inflammation, cell death mechanisms, and intracellular proteolytic cascades. The gastric epithelial context provides physiological relevance for studying DPP9-mediated regulation of innate immune responses, particularly in the gastric mucosa where chronic inflammation can promote carcinogenesis.
Dipeptidyl peptidase 9 (DPP9) is an intracellular serine protease that cleaves N-terminal dipeptides from target proteins and functions as a critical negative regulator of the NLRP1 and CARD8 inflammasomes. Under basal conditions, DPP9 binds and maintains NLRP1 and CARD8 in an autoinhibited confirmation. Upon DPP9 inhibition or genetic disruption, NLRP1 and CARD8 become activated, nucleating ASC-dependent caspase-1 activation, which leads to proteolytic maturation and secretion of pro-inflammatory cytokines IL-1?? and IL-18, as well as cleavage of gasdermin D, executing pyroptotic cell death. Upstream regulators include interferon-gamma and pathogen-associated molecular patterns, while pharmacological inhibitors like Val-boroPro directly target DPP9. Downstream, the pathway converges on caspase-1, IL-1??, IL-18, and gasdermin D, with NLRP1 and CARD8 as direct interacting partners.
In the AGS gastric adenocarcinoma background, DPP9 knockout creates a unique platform to dissect how inflammasome activation intersects with oncogenic signaling and tumor microenvironment dynamics. Constitutive activation of the NLRP1/CARD8-ASC-caspase-1 axis may induce chronic inflammatory signaling, altering cytokine profiles (e.g., IL-1??, IL-18) that can influence tumor cell proliferation, invasion, and immune evasion. Moreover, because pyroptotic cell death is inflammatory, DPP9-deficient AGS cells allow researchers to study the interplay between programmed cell death pathways and inflammatory responses in the context of gastric cancer, potentially revealing novel therapeutic vulnerabilities or biomarkers.
Key research applications include detailed inflammasome regulation studies, particularly for NLRP1 and CARD8 activation mechanisms; investigation of pyroptosis in gastric cancer; identification of DPP9 substrates; and evaluation of anti-cancer therapeutics targeting inflammatory signaling. This knockout model is compatible with Western blotting for caspase-1 and gasdermin D cleavage, IL-1?? ELISA, LDH release assays, DPP9 enzymatic activity assays, RT-qPCR for DPP9 transcript analysis, and flow cytometry using Annexin V/PI. For further technical details or custom inquiries, please contact Ascent Research.
