The CD4 Knockout DLD-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the DLD-1 human colorectal adenocarcinoma cell line, featuring targeted disruption of the CD4 gene to create a loss-of-function model. This polyclonal pool consists of a heterogeneous mixture of cells with varied editing outcomes, reflecting the population-level gene disruption typical of polyclonal knockout formats. The product is designed for functional studies where assessing overall knockout effects in a bulk cell population is advantageous, such as in drug screening or signaling assays.
The DLD-1 host cell line is a well-characterized model of human colorectal adenocarcinoma, harboring key oncogenic mutations in APC, KRAS, TP53, and PIK3CA. These genetic alterations drive canonical cancer pathways, including Wnt, MAPK, and PI3K signaling, making DLD-1 a relevant system for studying tumor biology and therapeutic responses. In this context, the CD4 knockout introduces a defined perturbation to investigate potential non-immune roles of CD4 or to serve as a control for CD4-dependent pathways in colorectal cancer research.
The CD4 gene encodes a membrane glycoprotein acting as a co-receptor on T helper cells by binding MHC class II molecules, which stabilizes TCR-pMHC interactions and recruits Lck kinase to phosphorylate CD3 ITAMs. This initiates signaling through ZAP70, LAT, and PLC-??1, propagating via MAPK/ERK, NF-??B, NFAT, and AP-1 pathways to drive cytokine production, including IL-2 and IFN-??. Upstream regulators include TCR activation, MHC class II, cytokines, and transcription factors ThPOK and RUNX3. CD4 also interacts directly with Lck, HIV gp120, and the TCR/CD3 complex, underscoring its role in both immune signaling and viral entry.
In the DLD-1 colorectal adenocarcinoma background, the CD4 knockout model enables dissection of CD4-dependent signaling independent of endogenous T cell receptor complexes, offering insights into potential non-immune functions of CD4. This engineered system facilitates study of CD4 interactions with MHC class II and downstream effectors like Lck and ZAP70 in a cancer setting, supporting research into tumor cell biology, immune evasion, and therapeutic targeting in colorectal cancer. The defined genetic mutations in DLD-1 (APC, KRAS, TP53, PIK3CA) provide a consistent background for evaluating CD4-related pathways in the context of oncogenic signaling.
Typical research applications include examination of CD4 function in colorectal cancer cells, investigation of CD4-independent immune modulation, and high-throughput drug screening for compounds affecting CD4-related pathways. The polyclonal knockout population is compatible with flow cytometry, western blotting, RT-qPCR, co-immunoprecipitation with MHC class II, phospho-Lck/ZAP70 detection, cytokine secretion assays (IL-2, IFN-??), proliferation, migration/invasion studies, and drug sensitivity testing with immune checkpoint inhibitors. For additional information or custom application inquiries, please contact Ascent Research.
