Ascent Research introduces the CCR9 Knockout HEK293 Polyclonal Cells, a CRISPR/Cas9-mediated gene disruption model that ablates expression of the chemokine receptor CCR9. This polyclonal knockout cell population is derived from HEK293 cells and provides a heterogeneous platform for loss-of-function studies of the CCL25-CCR9 signaling axis. The use of CRISPR/Cas9 technology ensures efficient targeting of the CCR9 locus, creating a versatile tool for investigating chemokine receptor biology, mucosal immunity, and translational research applications.
The host cell line HEK293 is a well-characterized human embryonic kidney epithelial cell line immortalized by adenovirus type 5 DNA. These cells are widely employed in biomedical research for heterologous expression and signal transduction studies due to their robust growth and ease of transfection. Importantly, HEK293 cells lack endogenous expression of CCR9, making them an ideal background for examining exogenous CCR9-dependent functions without interference from native receptor activity. Their epithelial nature additionally supports studies of adhesion and migration pathways relevant to intestinal epithelial biology.
CCR9 functions as a G protein-coupled receptor that specifically binds the chemokine ligand CCL25. Upon CCL25 engagement, CCR9 activates G??i proteins, leading to inhibition of adenylyl cyclase and a reduction in intracellular cAMP levels. Concurrently, ??-arrestin recruitment triggers MAPK/ERK phosphorylation and downstream signaling. The receptor also promotes leukocyte chemotaxis by coupling to integrin activation, particularly ??4??7, and induces calcium flux and PI3K-AKT pathway stimulation. CCR9 expression is upregulated by TNF, IL-1??, and retinoic acid, and its desensitization involves ??-arrestin-1, ??-arrestin-2, and GRK2.
In the HEK293 cell background, these CCR9 knockout polyclonal cells serve as a powerful model for dissecting CCL25-triggered signaling cascades and functional outcomes. The absence of endogenous CCR9 ensures that any observed responses in reconstituted systems or comparative studies directly reflect the actions of the transfected receptor. The polyclonal composition mitigates clonal variation, providing a more representative snapshot of CRISPR-induced gene disruption and facilitating population-level analyses. This model is particularly relevant for investigating pathways governing lymphocyte homing to the small intestine and for exploring the receptor??s role in pathologies such as inflammatory bowel disease, celiac disease, and colorectal cancer.
Researchers can utilize these knockout cells in a range of assays: western blotting and RT-qPCR to confirm CCR9 loss, flow cytometry to detect surface expression, chemotaxis assays towards CCL25, cAMP measurement, phospho-ERK ELISA, and integrin-dependent adhesion assays. RNA-seq enables transcriptomic profiling of CCR9-mediated changes. These applications support drug screening efforts targeting the CCL25-CCR9 axis and advance mucosal immunology and inflammation research. For technical details and ordering, please reach out to Ascent Research.
