The CBFB Knockout HAP1 Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population designed for functional investigation of the core-binding factor subunit beta (CBFB) gene in a near-haploid human background. This loss-of-function model disrupts endogenous CBFB expression, providing a robust cellular system to dissect CBFB-dependent transcriptional programs in hematopoietic and leukemic contexts. The polyclonal format preserves genetic heterogeneity while abolishing target protein function, enabling population-level phenotypic analyses. Researchers can employ this model to interrogate the molecular consequences of CBFB loss, including altered differentiation capacity and oncogenic transformation, without the confounding effects of clonal selection.
The parental HAP1 cell line is a near-haploid fibroblast-like cell line derived from the KBM-7 chronic myeloid leukemia (CML) clone. Its haploid chromosome content simplifies mutagenesis and ensures efficient single-allele knockout, making it an ideal platform for studying recessive phenotypes. Originating from a Ph+ CML patient, HAP1 preserves key myeloid lineage features and supports hematopoietic gene expression programs. This genetic background is particularly relevant for modeling hematological malignancies and testing therapeutic vulnerabilities in a genetically tractable system with intact p53 and apoptotic pathways.
CBFB encodes the non-DNA-binding beta subunit of the core-binding factor transcription complex. It heterodimerizes with RUNX1 (AML1), RUNX2, and RUNX3 to allosterically regulate DNA binding and transcriptional activity of these master hematopoietic and osteogenic regulators. CBFB is instrumental in hematopoietic stem cell emergence and lineage commitment, functioning downstream of NOTCH signaling and upstream of critical targets such as CD4, CD8, IL2, CSF1R, RAG1, MYB, and MPO. The CBFB?CRUNX1 complex nucleates transcriptional hubs involving PU.1, GATA1, MYC, and CDKN1A, and its activity is modulated by interacting cofactors including HIPK2 and SIN3A. Disruption of CBFB impairs normal hematopoiesis and cooperates with secondary mutations to promote acute myeloid leukemia (AML), most notably in core-binding factor leukemias harboring inv(16)(p13q22) that create the CBFB-MYH11 fusion oncoprotein.
In the HAP1 near-haploid context, CBFB knockout creates a defined model to study the mechanistic underpinnings of CBF-driven leukemogenesis. The myeloid leukemia origin of the host line allows investigation of CBFB deficiency in a pre-malignant background without additional oncogenic drivers. Researchers can analyze how loss of CBFB alters RUNX1 genome occupancy, disrupts hematopoietic transcription factor networks, and sensitizes cells to targeted therapies. The polyclonal nature of the knockout population further enables detection of phenotypic heterogeneity and selection pressures that may mimic clonal evolution in leukemic progression.
This knockout product is suited for a wide range of experimental workflows. Applications include dissecting the role of CBFB in hematopoietic differentiation via colony-forming assays and immunophenotyping by flow cytometry; validating downstream targets through RT-qPCR and western blotting for CBFB and RUNX1; performing ChIP-seq to map genome-wide RUNX1 binding changes; and conducting RNA-seq transcriptome profiling to uncover deregulated pathways. Additionally, the cells provide a platform for drug-sensitivity screens in CBF-AML and for testing RUNX1-CBFB complex inhibitors. For further information or to inquire about custom gene-editing services, please contact Ascent Research.
