The IFIT3 Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the HT29 human colorectal adenocarcinoma epithelial cell line, featuring targeted disruption of the IFIT3 locus. This population provides a loss-of-function model for studying interferon-stimulated gene (ISG) biology and its roles in antiviral immunity and tumor suppression without the complications of clonal heterogeneity.
The parental HT29 cell line, originally isolated from a primary colorectal adenocarcinoma of a 44-year-old female, serves as a widely used model for colon cancer research, intestinal epithelial barrier function, and mucus production. When cultured under appropriate conditions, HT29 cells can differentiate into enterocyte-like cells, making them valuable for drug absorption studies and host-microbe interaction analyses. Their well-characterized signaling networks and responsiveness to interferon stimulation render them an ideal background for dissecting ISG function.
IFIT3 encodes a tetratricopeptide repeat domain protein potently induced by type I interferons (IFN-??/??) and IFN-?? through JAK-STAT signaling. Upstream regulators include IRF3, IRF7, STAT1, STAT2, and IRF9, along with pattern recognition receptors RIG-I, MDA5, and TLR3. Upon induction, IFIT3 binds viral RNA and complexes with IFIT1 and IFIT2, inhibiting viral translation by sequestering eIF3. In cancer cells, IFIT3 exerts tumor-suppressive functions by downregulating Cyclin D1 and MMP9, upregulating Bax and Caspase-3, and suppressing Bcl-2, thereby inhibiting proliferation, migration, and invasion through interference with MAPK/ERK and PI3K/AKT pathways.
Genetic disruption of IFIT3 in HT29 cells eliminates its dual antiviral and antineoplastic activities. Loss of IFIT3 abrogates the restriction of viral replication normally mounted by interferon-activated complexes including IFIT1, IFIT2, TRIM25, and MAVS, rendering cells permissive to viral pathogens such as vesicular stomatitis virus and influenza. Concurrently, removal of IFIT3-mediated repression of oncogenic signaling may enhance proliferative and metastatic capacity, characterized by elevated Cyclin D1 and MMP9. This model allows direct investigation of how ISG networks interface with cancer hallmarks in a colon epithelial context.
The IFIT3 Knockout HT29 Polyclonal Cells enable mechanistic studies of antiviral innate immunity via viral infection assays (VSV, influenza), interrogation of interferon signaling by western blotting and RT-qPCR for ISGs, and apoptosis analysis by Annexin V/PI flow cytometry. Colorectal cancer researchers can employ these cells for proliferation (MTT), Transwell migration/invasion, and drug sensitivity screens to investigate IFIT3??s role in tumor progression. The polyclonal population is compatible with immunofluorescence and RNA-seq transcriptome profiling. For further information, please contact Ascent Research.
