The CD47 Knockout HAP1 Polyclonal Cells product comprises a CRISPR/Cas9-edited polyclonal knockout cell population targeting the CD47 gene in the HAP1 cell line. This polyclonal population is generated through CRISPR/Cas9-mediated gene disruption, yielding a heterogeneous pool of cells with loss-of-function mutations. The knockout model provides a powerful tool for studying CD47-dependent signaling and immune evasion without clonal selection biases, and the polyclonal nature ensures diverse representation of gene disruption outcomes.
The host cell line, HAP1, is a human near-haploid cell line originally derived from the KBM-7 chronic myeloid leukemia cell line. HAP1 cells are haploid for most chromosomes, except a disomic region on chromosome 8 and a fragment of chromosome 15, enabling unambiguous gene disruption with a single targeting event. The near-haploid karyotype eliminates the need for biallelic modification, making HAP1 particularly valuable for genetic knockout studies. HAP1 maintains key characteristics of the parental leukemia line, including hematopoietic marker expression and growth factor dependency, while adherent monolayer growth simplifies cell-based assays.
CD47 is a widely expressed transmembrane glycoprotein that acts as a critical immune checkpoint by engaging SIRP?? on macrophages. Upon binding, CD47 triggers ITIM phosphorylation and recruitment of SHP-1 and SHP-2 phosphatases, which inhibit phagocytic synapse formation. This dominant ??don??t eat me?? signal enables cancer cells to evade innate immune clearance. CD47 also interacts with integrins ??v??3 and ??2??1, thrombospondin-1, and VEGFR2, contributing to cell adhesion, migration, and nitric oxide production. Expression is upregulated by TNF-??, IL-6, NF-??B, and HIF-1??, linking CD47 to cancer, atherosclerosis, and infectious diseases.
In the HAP1 near-haploid background, CD47 knockout provides an exceptionally clean loss-of-function model for elucidating CD47-mediated signaling. The leukemic origin is particularly relevant for studying hematological malignancies, where CD47 overexpression contributes to immune evasion. Disruption allows dissection of downstream consequences on integrin activation, SIRP??-SHP-1/2 signaling, and phagocytosis regulation, free from confounding expression from a second allele. This model enables precise assessment of how CD47 loss sensitizes cells to macrophage-mediated clearance and may identify therapeutic vulnerabilities.
This knockout cell population is suited for a range of applications. In immunology, it facilitates phagocytosis assays to quantify macrophage engulfment, with or without antibody opsonization, and flow cytometry to confirm CD47 surface loss. In cancer biology, xenograft tumor models can evaluate tumor growth and immune infiltration upon CD47 disruption. Biochemical studies using co-immunoprecipitation and western blotting can probe changes in SIRP?? interaction partners and downstream phosphorylation. Additionally, the model supports high-throughput screening for CD47 pathway modulators. For more detailed technical information, please contact Ascent Research.
