The ICOSLG Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the human HT29 colorectal adenocarcinoma cell line, featuring targeted disruption of the ICOSLG gene. This loss-of-function model is designed for investigating the biological role of ICOSLG in an intestinal epithelial background, particularly in the context of tumor?Cimmune crosstalk and costimulatory signaling.
HT29 cells serve as a well-characterized epithelial model for colorectal cancer and intestinal cell differentiation studies. These cells exhibit key features of intestinal epithelium, including the capacity to form polarized monolayers and express differentiation markers. The knockout HT29 background provides a physiologically relevant system to examine how epithelial ICOSLG expression influences immune effector functions within the tumor microenvironment.
ICOSLG encodes the inducible T-cell costimulator ligand (ICOSL), a B7 family member that functions as the sole ligand for ICOS on activated T cells. ICOSL engagement triggers PI3K/AKT signaling through recruitment of the PI3K p85 regulatory subunit, leading to AKT phosphorylation and mTORC1 activation, which promotes T-cell proliferation, survival, and cytokine production. Upstream regulators include TNF-??, IL-4, IFN-??, and CD40?CCD40L-mediated NF-??B activation. Downstream, ICOSL enhances expression of IL-4, IL-10, IL-21, and the master transcription factor Bcl-6, critical for T follicular helper cell development and germinal center formation. ICOSL can also interact with CD80 and CD86, adding complexity to its immune-modulatory functions.
In the HT29 colorectal cancer context, ICOSLG-mediated costimulation may modulate anti-tumor immunity or foster immune evasion. Disruption of ICOSLG allows researchers to dissect how epithelial ligand loss reshapes T-cell activation, cytokine profiles, and tumor progression. This model holds translational relevance for studying cancer immunotherapy resistance, autoimmune diseases, primary immunodeficiencies, and allergic inflammation, where ICOS?CICOSL signaling is implicated.
This knockout tool supports diverse applications, including T-cell co-culture proliferation assays, flow cytometric confirmation of ICOSLG ablation, western blotting for phospho-AKT (Ser473), multiplex cytokine analysis (IL-4, IL-10, IL-21), RT-qPCR, and RNA-seq transcriptomic profiling. Migration/invasion assays can further assess tumor cell behavior. These polyclonal knockout cells provide a robust system for investigating epithelial immune-modulatory mechanisms. For further information or to place an order, contact Ascent Research.
