The KLRB1 Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-mediated gene-disrupted polyclonal cell population derived from the HT29 human colorectal adenocarcinoma line, engineered to ablate expression of the KLRB1 gene. This polyclonal format preserves the genetic heterogeneity of the parental pool and avoids the artifacts inherent to clonal selection, providing a reliable loss-of-function model for bulk functional studies.
HT29 is an epithelial cell line originally established from a primary colorectal adenocarcinoma of a 44-year-old Caucasian female. The line harbors well-characterized mutations in APC, TP53, and KRAS, reflecting critical steps in colorectal carcinogenesis. HT29 cells are widely employed as a model of intestinal epithelial barrier function and are extensively used in cancer research, including studies of tight junction biology, oncogenic signaling, and drug sensitivity.
The KLRB1 gene encodes CD161, a C-type lectin inhibitory receptor predominantly expressed on NK cells and T cells. CD161 features an immunoreceptor tyrosine-based inhibition motif (ITIM) in its cytoplasmic domain. Binding to its ligand CLEC2D (LLT1) induces ITIM phosphorylation, which recruits the SH2-domain-containing phosphatases SHP-1 and SHP-2. These phosphatases dephosphorylate the adaptor protein LAT and the guanine nucleotide exchange factor Vav1, thereby dampening downstream mitogen-activated protein kinase (MAPK) and nuclear factor of activated T cells (NFAT) signaling cascades. Consequently, CD161 engagement suppresses the production of pro-inflammatory cytokines such as interferon-?? (IFN-??) and tumor necrosis factor-?? (TNF-??) and reduces cellular cytotoxicity. Key upstream regulators include cytokines IL-12 and IL-15, as well as the transcription factor ZBTB7B (ThPOK).
In the context of colorectal adenocarcinoma, CD161-mediated inhibitory signaling may influence immune evasion by modulating tumor-immune cell interactions. Knocking out KLRB1 in HT29 cells provides a defined system to investigate CD161-dependent crosstalk between epithelial tumor cells and natural killer (NK) or T lymphocytes, especially using co-culture assays. This model facilitates the dissection of immune checkpoint mechanisms within the gastrointestinal microenvironment and aids in understanding how CD161 impacts tumor cell resistance to immune-mediated lysis.
Typical applications include functional validation of the CD161/CLEC2D axis in colorectal cancer, mechanistic studies of tumor immune resistance, and compound screening to identify pathway modulators. Recommended assays include Western blotting and flow cytometry for confirming KLRB1 ablation, NK cell cytotoxicity assays, IFN-?? ELISA, cell proliferation assays, and phospho-signaling analysis. For technical inquiries or additional product information, please contact Ascent Research.
