The Il4i1 Knockout RAW 264.7 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the mouse macrophage cell line RAW 264.7. This product disrupts the Il4i1 gene, enabling loss-of-function studies of IL4I1 in an immunocompetent host. The polyclonal format provides a heterogeneous null background, avoiding clonal selection effects.
RAW 264.7 macrophages originate from BALB/c mice transformed with Abelson murine leukemia virus. These cells serve as a model for innate immune effectors, exhibiting phagocytosis, inflammatory cytokine production, and antigen presentation. They respond robustly to stimuli, making them ideal for investigating macrophage-dependent immune modulation.
IL4I1 functions as an L-amino acid oxidase that catabolizes phenylalanine into hydrogen peroxide, ammonium, and kynurenic acid. Its expression is driven by STAT6 activation downstream of IL-4 and IL-13 receptors. IL4I1 employs FAD as a cofactor and suppresses T cell responses by inhibiting T cell receptor signaling and activating the aryl hydrocarbon receptor (AHR). Upon activation, AHR dimerizes with ARNT and upregulates genes such as CYP1A1 and IL-22. This IL-4/IL-13/STAT6/IL4I1/AHR pathway fosters immune tolerance and tumor immune evasion.
Knocking out Il4i1 in RAW 264.7 cells disrupts the macrophage-to-T-cell immunosuppressive axis, offering a valuable system to examine how metabolic products like kynurenic acid modulate adaptive immunity. This model allows dissection of macrophage-intrinsic IL4I1 roles in antigen processing, ROS-mediated signaling, and cytokine production, providing insights into inflammation and immune escape mechanisms.
Researchers can employ these cells in co-culture with T cells to measure proliferation suppression, AHR reporter assays, and cytokine ELISAs for IL-4 and IL-13. Advanced uses include flow cytometry for T cell activation markers, RNA-seq for transcriptomic profiling, and immunofluorescence for AHR localization. This tool is suited for cancer immunotherapy, chronic infection, autoimmunity, and inflammatory disease studies. For detailed support, contact Ascent Research.
