The CD47 Knockout NCI-H1975 Polyclonal Cells product consists of a polyclonal cell population generated by CRISPR/Cas9-mediated disruption of the CD47 gene in the NCI-H1975 human lung adenocarcinoma cell line. This polyclonal knockout pool introduces loss-of-function mutations across multiple cells, providing a heterogeneous model to study CD47-dependent signaling without the constraints of clonal selection. The edited population retains the parental line??s epithelial origin and key oncogenic driver mutations, enabling robust investigation of CD47??s role in immune evasion and cancer biology. Researchers can use this model to probe phagocytosis checkpoints and macrophage?Ctumor cell interactions in an experimentally accessible system.
The NCI-H1975 host cell line was isolated from a patient with non-small cell lung cancer (NSCLC) and harbors clinically relevant activating mutations in EGFR (epidermal growth factor receptor) and PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha). These mutations drive constitutive mitogenic and survival signaling, recapitulating molecular features frequently observed in lung adenocarcinomas. NCI-H1975 cells grow as an adherent monolayer with epithelial morphology and are widely employed as a NSCLC model for drug screening, targeted therapy research, and tumor microenvironment studies. The presence of mutant EGFR and PIK3CA also makes this line suitable for investigating cross-talk between oncogenic pathways and innate immune checkpoints.
CD47 encodes a cell-surface glycoprotein that functions as an innate immune checkpoint by interacting with SIRPA (signal-regulatory protein alpha) on macrophages, triggering SHP-1 (PTPN6) and SHP-2 (PTPN11) phosphatase recruitment to the phagocytic synapse. This signaling cascade inhibits myosin-II accumulation and downstream phagocytic execution machinery, thereby preventing engulfment of CD47-expressing cells. CD47 is transcriptionally upregulated by hypoxia, inflammatory cytokines such as TNF-alpha and IL-1beta, as well as the transcription factors MYC and NF-kB. Beyond SIRPA, CD47 interacts with thrombospondin-1 and integrins including alphaVbeta3 and alpha2beta1, and it associates with VEGFR2, linking it to angiogenesis and matrix remodeling. In the context of cancer, CD47-mediated immune evasion allows tumor cells to escape macrophage-mediated clearance.
Disruption of CD47 in NCI-H1975 cells removes a dominant “don??t eat me” signal, creating a model system that sensitizes tumor cells to antibody-dependent cellular phagocytosis (ADCP) and macrophage-mediated cytotoxicity. Because NCI-H1975 carries EGFR and PIK3CA mutations, this knockout line enables dissection of how oncogenic signaling intersects with innate immune checkpoints. It can be used to explore whether EGFR or PI3K pathway inhibitors synergize with CD47 blockade to promote tumor cell clearance. Additionally, the polyclonal nature of the knockout allows assessment of functional heterogeneity and selection pressures that may arise during immune targeting, making it a valuable tool for preclinical immunotherapy research.
Typical applications include flow cytometry-based CD47 expression profiling, phagocytosis assays with primary macrophages or macrophage cell lines, ADCP studies using therapeutic antibodies, western blot analysis of SIRPA/SHP-1/SHP-2 signaling, and in vivo tumor challenge models to evaluate immune-mediated tumor rejection. These assays support investigation of immune checkpoint blockade, integrin signaling, and hypoxia-driven immune evasion. For technical inquiries, please contact Ascent Research.
