The EGFR Knockout THP-1 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population in which the human EGFR gene has been functionally disrupted in the THP-1 acute monocytic leukemia cell line. This polyclonal knockout product provides a heterogeneous pool of gene-edited cells, enabling loss-of-function studies without clonal selection artifacts. The EGFR gene encodes the epidermal growth factor receptor, a receptor tyrosine kinase critical for cell proliferation, survival, and differentiation. By ablating EGFR expression, researchers can investigate the receptor??s role in monocyte/macrophage biology and its contributions to cancer-related processes. This model is generated using CRISPR/Cas9-mediated gene disruption, ensuring robust and specific knockout across the polyclonal population, suitable for a wide range of downstream applications in signal transduction and drug discovery research.
The THP-1 cell line was originally isolated from the peripheral blood of a 1-year-old male patient with acute monocytic leukemia (AML-M5 subtype). These cells serve as a well-characterized and widely used model for studying monocyte-to-macrophage differentiation, as well as acute myeloid leukemia. THP-1 cells can be differentiated into macrophage-like cells upon treatment with phorbol esters (e.g., PMA), recapitulating many aspects of primary macrophage function, including cytokine secretion, phagocytosis, and surface marker expression. Consequently, EGFR knockout in this cellular context allows interrogation of how EGFR signaling influences both leukemia cell-autonomous properties and the functional plasticity of monocytic/macrophage lineages.
At the molecular level, EGFR functions as a transmembrane receptor that, upon binding to ligands such as EGF, TGF-??, amphiregulin, betacellulin, and NRG1, undergoes dimerization and autophosphorylation, triggering intracellular signaling cascades. Key downstream pathways include the RAS?RAF?MEK?ERK (MAPK/ERK) cascade, which phosphorylates transcription factors such as ELK1, FOS, and JUN to promote proliferation; the PI3K?AKT?mTOR axis, which enhances survival and metabolic activity; and the JAK?STAT pathway, leading to STAT3-mediated transcription of MYC and other target genes. Additionally, EGFR activates PLC???PKC signaling. Adaptor proteins GRB2 and SHC directly couple activated EGFR to SOS and RAS, whereas the ubiquitin ligase CBL mediates receptor downregulation. EGFR also heterodimerizes with ERBB2, ERBB3, and ERBB4, expanding signaling diversity. Disruption of EGFR in THP-1 polyclonal knockout cells abrogates these ligand-dependent signals, resulting in decreased phosphorylation of ERK/MAPK, AKT, and STAT3, thereby attenuating proliferative and survival outputs.
In the THP-1 macrophage model, EGFR knockout provides a powerful tool for dissecting the role of EGFR signaling in monocyte/macrophage function and its contribution to the tumor microenvironment. EGFR signaling has been implicated in macrophage activation, M1/M2 polarization, and the production of pro-inflammatory cytokines. Loss of EGFR in THP-1 cells may impair macrophage-mediated tumor cell support, alter phagocytic capacity, and reduce secretion of growth factors that promote angiogenesis and metastasis. This polyclonal knockout model thus enables the study of macrophage-intrinsic EGFR functions without the confounding effects of clonal variability, offering a physiologically relevant system to investigate how EGFR-dependent pathways intersect with innate immune responses in cancer and inflammatory diseases.
This EGFR knockout THP-1 polyclonal cell population is ideal for a variety of research applications, including cancer drug resistance studies where the impact of EGFR loss on macrophage-mediated chemoresistance can be evaluated; macrophage signaling and inflammation experiments using cytokine profiling and phagocytosis assays; and cell proliferation, survival, and apoptosis analyses through MTS, BrdU, and Annexin V assays. Researchers can also employ western blotting to confirm EGFR ablation and assess phospho-ERK levels, RT?qPCR to quantify expression of downstream targets such as MYC and FOS, flow cytometry to monitor EGFR surface expression, and migration/invasion assays to examine functional consequences. The model is further suitable for phospho?signaling proteomics and high?throughput drug screening in the context of leukemia and solid tumor microenvironment studies. For additional information, please contact Ascent Research.
