The CD3G Knockout HAP1 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population in which the CD3G gene has been disrupted in the HAP1 near-haploid human cell line. This gene-edited pool provides a heterogeneous loss-of-function model for investigating CD3G-dependent signaling without clonal isolation, enabling robust population-level analyses of protein function and pathway dependencies.
The host cell line, HAP1, is a near-haploid human cell line derived from the KBM-7 chronic myeloid leukemia cell line. Its near-haploid karyotype reduces genetic redundancy and facilitates unambiguous gene targeting, making it a widely adopted model for haploid genetic screens and functional genomics studies. HAP1 cells retain many signaling pathways relevant to hematopoietic cancer biology, providing a simplified yet biologically informative background for studying gene function.
CD3G encodes the gamma subunit of the T-cell receptor (TCR) complex, essential for surface expression and signal transduction. Upon TCR ligation, LCK and FYN phosphorylate ITAMs on CD3G and other CD3 chains, recruiting ZAP70. Activated ZAP70 phosphorylates LAT and PLC??1, triggering calcium flux and MAPK cascades that activate NFAT, NF-??B, and AP-1 transcription factors, promoting IL-2 expression and T-cell activation. CD3G interacts directly with CD3D, CD3E, CD3Z, and TCR????, as well as LCK, FYN, ZAP70, and NCK1, to form a functional signalosome.
Although HAP1 cells are not of T-cell lineage, they provide a unique platform to dissect CD3G-mediated signaling events in a reductionist system amenable to high-throughput screening. The disruption of CD3G in this background allows researchers to study the intrinsic signaling capacity of TCR components in the absence of complex immune cell interactions, facilitating the identification of direct regulatory partners and drug targets. This model is particularly relevant for understanding the molecular basis of immunodeficiencies such as CD3G-linked severe combined immunodeficiency (IMD17) and for exploring mechanisms of immune evasion in cancer.
This polyclonal knockout cell pool is well-suited for a variety of research applications, including T-cell development studies, immunodeficiency disease modeling, and dissection of the TCR signaling cascade. The cells can be employed in drug screening campaigns to identify immunomodulatory compounds that bypass or restore CD3G function, as well as in haploid genetic screens to uncover novel regulators of the pathway. Representative assays include Western blotting for CD3G protein loss, RT-qPCR for mRNA confirmation, co-immunoprecipitation to assess complex assembly, flow cytometry for surface expression of CD3 chains, and drug sensitivity assays. For technical inquiries and customized support, please contact Ascent Research.
