The ITGAM Knockout CAL-27 Polyclonal Cells product is a CRISPR/Cas9-edited polyclonal cell population featuring targeted disruption of the ITGAM gene in the CAL-27 host line. ITGAM encodes the integrin ??M (CD11b) subunit, which partners with CD18 to form the Mac-1 complex. As a polyclonal knockout pool, this model eliminates the need for clonal isolation while providing a robust loss-of-function background for studying CD11b-dependent adhesion, migration, and phagocytosis.
CAL-27 is an adherent human tongue squamous cell carcinoma epithelial line established from a biopsy. It serves as a widely used model for oral squamous cell carcinoma, exhibiting characteristics relevant to cancer cell adhesion, extracellular matrix remodeling, and invasion. While CD11b is typically myeloid, ectopic expression or complementation studies in this epithelial background enable dissection of integrin ??M signaling in a cancer context, facilitating research into tumor-stroma interactions and metastatic mechanisms.
CD11b pairs with CD18 to form Mac-1, which binds ligands such as ICAM-1, iC3b, fibrinogen, and glycosaminoglycans. Its expression is induced by TNF-??, IL-1??, LPS, and GM-CSF through transcription factors PU.1, NF-??B, and AP-1. Upon engagement, Mac-1 activates Src and Syk kinases, triggering PI3K/Akt and Rac1/RhoA pathways that drive ARP2/3-mediated actin polymerization, phagocytic cup formation, and NADPH oxidase complex assembly. Downstream, NF-??B signaling promotes IL-6 and TNF-?? production. ITGAM disruption uncouples these cascades, providing a clean system for dissecting each component.
In CAL-27 cells, ITGAM knockout creates a model for investigating ??M integrin function in an epithelial carcinoma environment. The lack of endogenous CD11b expression makes these cells ideal for re-introducing wild-type or variant ITGAM constructs, enabling functional complementation and structure-function analysis. This system also allows exploration of Mac-1 contributions to cancer cell adhesion and migration, with relevance to leukocyte adhesion deficiency, inflammatory diseases, and cancer metastasis. Additionally, it provides a platform to study ITGAM polymorphisms linked to systemic lupus erythematosus and lupus nephritis.
Research applications include cell adhesion assays on ICAM-1 substrates, transwell migration/invasion assays, and phagocytosis of iC3b-opsonized particles. Downstream signaling can be assessed by phospho-Syk and phospho-Akt analysis. Western blotting, flow cytometry, and RT-qPCR enable confirmation of CD11b knockdown, while Sanger sequencing verifies genomic targeting. These polyclonal knockout cells are also suited for drug screening of Mac-1 inhibitors and tumor-immune co-culture studies. For further information, please contact Ascent Research.
