The ANXA3 Knockout THP-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal population derived from the human THP-1 monocytic cell line, designed for loss-of-function studies of Annexin A3 (ANXA3). This polyclonal format retains the heterogeneity of the parental pool, offering a physiologically relevant model to study ANXA3-dependent functions without the limitations of single-clone selection.
THP-1 cells, originating from an acute monocytic leukemia, serve as a standard model for monocyte/macrophage differentiation, phagocytosis, and inflammatory signaling. Upon stimulation with phorbol esters, they differentiate into adherent macrophage-like cells, recapitulating key innate immune processes. The ANXA3 knockout in this background provides a genetically defined platform to investigate ANXA3??s roles in monocyte and macrophage biology, including leukemogenesis.
ANXA3 encodes a calcium- and phospholipid-binding protein that inhibits phospholipase A2 (PLA2), thereby reducing arachidonic acid release and pro-inflammatory eicosanoid production such as prostaglandin E2 (PGE2). It is transcriptionally activated by NF-??B, STAT3, and Wnt/??-catenin signaling, and is also induced by TGF-?? stimulation. Downstream, ANXA3 represses NF-??B activity via I??B?? stabilization, modulates caspase-3-dependent apoptosis, and alters cyclin D1 expression to affect cell cycle progression. ANXA3 directly binds phosphatidylserine and calcium ions, and associates with c-Met and other annexins, integrating membrane trafficking with signal transduction. Consequently, ANXA3 engages the MAPK/ERK cascade through ERK1/2, the PI3K/AKT/mTOR axis, and the ??-catenin/TCF/LEF transcription complex, promoting cellular proliferation, survival, and migration. Overexpression of ANXA3, frequently detected in hepatocellular carcinoma, gastric cancer, and acute myeloid leukemia, drives oncogenic processes via sustained activation of NF-??B and AKT.
In the THP-1 monocytic background, ANXA3 knockout provides a powerful tool to decipher its function in innate immune cells. The PLA2-inhibitory activity of ANXA3 directly controls the eicosanoid synthesis pathway, affecting PGE2 levels and downstream NF-??B-dependent cytokine production (e.g., TNF-??, IL-6). Researchers can study the impact of ANXA3 loss on phagocytosis and migration, two key macrophage effector functions. Additionally, because THP-1 is a leukemia-derived line, this model facilitates investigations into how ANXA3 contributes to leukemogenesis, drug resistance, and exosome-mediated intercellular communication.
Applications for this polyclonal knockout model encompass transcriptomic profiling by RNA-seq, quantitative protein analysis via western blotting and flow cytometry, and functional assessments such as phagocytosis and migration assays. ELISA-based measurement of TNF-??, IL-6, and PGE2 enables direct interrogation of inflammatory mediator output. Complementary viability (MTT) and apoptosis (Annexin V staining) assays further delineate the cytoprotective roles of ANXA3. Together, these approaches permit systematic dissection of ANXA3 signaling in innate immunity and cancer. For further technical details, please contact Ascent Research.
