The ICAM1 Knockout HAP1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population derived from the near-haploid HAP1 cell line. This product consists of a heterogeneous pool of cells harboring targeted disruptions in the ICAM1 gene, generated by CRISPR/Cas9 technology to create a loss-of-function model. The polyclonal format maintains genetic diversity, making it well-suited for pooled screening and reducing clonal selection artifacts. This model is intended for advanced functional studies of ICAM1 in adhesion, migration, and inflammatory signaling.
The HAP1 parental cell line is a near-haploid human cell line derived from the chronic myeloid leukemia KBM-7 cell line, which originated from a bone marrow sample. HAP1 cells maintain a stable haploid karyotype with disomy only for chromosome 8, simplifying genetic analyses by eliminating functional redundancy from a second allele. This haploid nature facilitates efficient gene knockout and has established HAP1 as a preferred model for functional genomics, haploid genetic screens, and CRISPR-based studies.
ICAM1 (Intercellular Adhesion Molecule 1, CD54) is a cell surface glycoprotein that functions as a ligand for the ??2 integrins LFA-1 (ITGAL/ITGB2) and Mac-1 (ITGAM/ITGB2), mediating firm adhesion and transendothelial migration of leukocytes. Its expression is transcriptionally upregulated by pro-inflammatory cytokines such as TNF??, IL-1??, and IFN-?? through NF-??B, AP-1, and STAT1 pathways. Upon engagement, ICAM1 activates downstream signaling cascades involving the non-receptor tyrosine kinase SRC, the small GTPase RHOA, PI3K, and the MAP kinases MAPK1/3 (ERK2/1), leading to cytoskeletal reorganization, endothelial barrier opening, and induction of VCAM1 and other adhesion molecules. ICAM1 also interacts with CD43, ezrin, moesin, fibrinogen, and hyaluronan, and serves as a cellular receptor for rhinovirus. Disruption of ICAM1 ablates these interactions, impairing leukocyte adhesion, diapedesis, and downstream signaling.
In the context of the HAP1 near-haploid cell line, knockout of ICAM1 creates a uniform loss-of-function model that avoids the confounding effects of heterozygous expression. The myeloid origin of HAP1 cells renders this knockout pool particularly relevant for studying ICAM1-dependent processes in a leukocytic lineage, including adhesion, migration, and inflammatory signal transduction. The simplified genetic background of HAP1 cells enhances the clarity of phenotypic readouts, making this model ideal for dissecting ICAM1’s role in cell?Ccell interactions and intracellular signaling without the complexity of diploidy. Furthermore, the polyclonal nature provides robustness for high-throughput screening applications.
These polyclonal knockout cells support diverse applications, including flow-based adhesion and Transwell transendothelial migration assays to study leukocyte trafficking. They provide a platform for anti-inflammatory drug screening targeting ICAM1?Cintegrin interactions, as well as cancer cell migration and metastasis research. Rhinovirus entry can be investigated via infection assays, while signaling consequences are assessed by Western blotting for phospho-SRC, phospho-MAPK1/3, and downstream effectors. Flow cytometry enables quantification of LFA-1 binding, and co-immunoprecipitation with ITGAL/ITGB2 or ITGAM/ITGB2 elucidates protein interactions. Permeability assays and immunofluorescence for junctional proteins such as CDH5 and PECAM1 extend the model to endothelial barrier studies. For technical inquiries, please contact Ascent Research.
