The CCR8 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal population with disruption of the CCR8 gene, encoding the CCL1 chemokine receptor. This knockout model provides a pool of HAP1 cells harboring heterogeneous loss-of-function mutations, enabling robust functional studies without clonal bias. CCR8 is a G protein-coupled receptor critical for Th2 lymphocyte and regulatory T cell chemotaxis and is implicated in allergic inflammation and tumor immune evasion.
HAP1 cells are a near-haploid human cell line derived from the KBM-7 chronic myeloid leukemia line. With a haploid karyotype except for a portion of chromosome 15, these fibroblast-like cells are a mainstay of CRISPR-based functional genomics and high-throughput screens. Their simplified genome facilitates knockout generation and phenotype interpretation, and the cells retain key signaling machinery relevant to chemokine receptor biology.
CCR8 signals upon binding its sole ligand CCL1, which is upregulated by IL-4 and IL-13 via STAT6. Ligand engagement activates Gi proteins (GNAI1, GNAI2), leading to calcium mobilization, MAPK1/3 (ERK1/2) phosphorylation, and PI3K?CAKT1 pathway stimulation. Downstream, Rho GTPases and actin polymerization drive cell migration. Receptor regulation involves arrestins ARRB1 and ARRB2 and the G?¦? subunits GNB1/GNG2, which modulate signaling and desensitization.
In the HAP1 background, CCR8 knockout eliminates CCL1-induced signaling, providing a clean system to dissect chemokine-mediated migration and survival pathways. The near-haploid genome minimizes genetic redundancy, allowing clear attribution of phenotypes to CCR8 loss. This model is particularly valuable for studying Th2- and Treg-relevant signaling, for identifying modifiers of the CCR8 pathway through functional-genomic screens, and for investigating compensatory mechanisms involving other chemokine receptors.
Applications include research into allergic inflammation, asthma, atopic dermatitis, T-cell lymphoma, and tumor immunosuppression. Functional assays such as flow cytometry for CCR8 surface expression, Transwell chemotaxis, calcium flux analysis, and Western blot for MAPK and AKT phosphorylation can be conducted. RT-qPCR permits assessment of downstream transcriptional responses. The polyclonal pools are also amenable to arrayed and pooled CRISPR modifier screens. Researchers are encouraged to contact Ascent Research for further information and custom inquiries.
