The CD300E Knockout HAP1 Polyclonal Cells comprise a CRISPR/Cas9-edited polyclonal knockout cell population designed to disrupt the CD300E gene in the HAP1 cell line. This heterogeneous pool of cells supports loss-of-function analysis of the CD300E-encoded activating immune receptor within a human myeloid leukemia context. The polyclonal format is well-suited for functional genomic screens and biochemical studies where population-level genetic variation reflects physiologically relevant conditions.
HAP1 is a near-haploid human cell line originating from the KBM-7 chronic myeloid leukemia (CML) model, featuring a haploid karyotype with disomy of chromosome 8. The near-haploid genome simplifies CRISPR/Cas9-mediated gene disruption, as targeting a single allele typically achieves functional knockout across most genomic regions. HAP1 cells retain key myeloid lineage traits, including phagocytic capability and expression of myeloid markers, providing an appropriate host for investigating myeloid receptors like CD300E.
CD300E (CLM-2/IRp60) is an activating transmembrane immunoreceptor on myeloid cells that recognizes phosphatidylserine on apoptotic cells, coupling via TYROBP/DAP12 to activate SYK kinase. This triggers PI3K-AKT and MAPK/ERK cascades, leading to NF-??B-driven transcription of pro-inflammatory cytokines such as IL-6 and TNF-??. CD300E expression is upregulated by Toll-like receptor ligands, TNF-??, and IFN-??, positioning it as a nexus between apoptosis detection and inflammatory response. Downstream effectors include SYK, PI3K, AKT, MAPK3/ERK1, and NFKB1.
Within the HAP1 myeloid leukemia background, CD300E disruption permits focused investigation of its roles in phagocytosis and cytokine production, devoid of compensation by other activating receptors. The near-haploidy ensures that the polyclonal knockout population largely represents effective loss-of-function, facilitating robust signaling studies. Because HAP1 cells natively express TYROBP/DAP12 and SYK, this model is ideal for dissecting ITAM-mediated pathways. Moreover, the CML origin offers a platform to examine how CD300E signaling intersects with leukemic processes and tumor-associated myeloid functions.
Core applications include efferocytosis assays using fluorescent apoptotic cells to quantify CD300E-dependent phagocytosis, and cytokine ELISAs to measure IL-6 and TNF-?? output upon stimulation with TLR agonists or apoptotic debris. Western blotting for CD300E and phospho-SYK, -AKT, and -ERK1/2 allows pathway activation profiling, while flow cytometry verifies receptor loss and RNA-seq identifies global transcriptional changes. These cells also enable drug sensitivity profiling to assess CD300E-dependent responses to kinase inhibitors or immunomodulators. For further technical inquiries, please contact Ascent Research.
