The KLRB1 Knockout AGS Polyclonal Cells represent a CRISPR/Cas9-mediated loss-of-function model in which the KLRB1 gene, encoding the CD161 inhibitory receptor, is disrupted within an engineered polyclonal population. This polyclonal knockout cell product, derived from the AGS human gastric adenocarcinoma epithelial cell line, provides a heterogeneous mixture of cells harboring a variety of gene-disrupted alleles, avoiding the selection bias of single-cell clones. The knockout is achieved through general CRISPR/Cas9-mediated gene targeting, eliminating the need for precise characterization of individual editing events while ensuring broad abrogation of CD161 protein expression across the population.
The AGS host cell line was originally isolated from a human gastric adenocarcinoma and has since become an established in vitro model for gastric mucosal epithelial biology. These cells retain key features of transformed gastric epithelial cells and are widely utilized in investigations of Helicobacter pylori pathogenesis, gastric carcinogenesis, and epithelial?Cimmune crosstalk. Their adherent, epithelial morphology and well-characterized growth properties facilitate a broad range of functional assays, making them an ideal platform to explore the consequences of KLRB1 disruption in a gastric cancer context.
CD161, encoded by KLRB1, functions as a C-type lectin inhibitory receptor prominently expressed on natural killer cells and subsets of T lymphocytes. Mechanistically, engagement of CD161 by its cognate ligand LLT1 (CLEC2D) leads to the phosphorylation of immunoreceptor tyrosine-based inhibitory motifs (ITIMs) and the subsequent recruitment and activation of the Src homology 2 domain-containing phosphatases SHP-1 and SHP-2. These phosphatases dephosphorylate key signaling intermediates downstream of activating receptors, including components of the PI3K/AKT and MAPK/ERK pathways, thereby inhibiting NF-??B and ERK activity. As a result, CD161 signaling attenuates cytotoxic effector functions and reduces the expression of pro-inflammatory cytokines. Upstream, CD161 expression is regulated by cytokines such as IL-15 and IL-2 and by the transcription factors T-bet and Eomes, and it is further modulated by T-cell receptor signaling.
In the context of gastric adenocarcinoma, the AGS cell line expressing endogenous or ectopic LLT1 can engage in bidirectional immune-regulatory interactions with tumor-infiltrating lymphocytes. Disruption of KLRB1 in AGS cells presents a unique opportunity to dissect the contribution of epithelial CD161??or the absence of CD161??to tumor?Cimmune cell communication. Since gastric cancers often exploit inhibitory receptor?Cligand interactions to evade immune surveillance, this knockout model allows researchers to test whether ablation of CD161 in epithelial cells alters LLT1-mediated signals, influences immune cell recruitment or activity, or remodels the tumor microenvironment in co-culture systems. Moreover, because AGS cells retain epithelial characteristics, the model enables the investigation of CD161-independent functions in gastric epithelial biology that may be unmasked upon gene inactivation.
This product empowers a wide array of experimental applications in academic and pharmaceutical research. It can be employed in gastric cancer research to evaluate tumor cell-intrinsic roles of CD161, in immune evasion studies by co-culturing knockout cells with primary NK cells or T cells and measuring alterations in cytotoxicity and cytokine release, and in host-pathogen interaction models assessing how CD161 status modifies epithelial responses to H. pylori infection. Additionally, it serves as a valuable tool in high-throughput drug screening for gastric cancer therapeutics and in functional genomics screens to delineate CD161-related signaling networks. Representative assays compatible with these cells include western blotting and flow cytometry to confirm loss of CD161 protein, RT-qPCR to quantify residual KLRB1 transcript, and cell-based readouts such as proliferation, apoptosis, migration, and invasion assays. For detailed technical support and ordering information, please contact Ascent Research.
