The CD163L1 Knockout HAP1 Polyclonal Cells constitute a CRISPR/Cas9-mediated gene-disrupted polyclonal population derived from the near-haploid human HAP1 cell line. This product provides a genetically heterogeneous pool of cells carrying diverse loss-of-function mutations in the CD163L1 locus, generated by non-homologous end joining following Cas9-directed double-strand breaks. As a polyclonal knockout reagent, it enables functional interrogation of CD163L1 in a population-level context, circumventing clonal selection bottlenecks while maintaining near?haploid genetic simplicity that facilitates straightforward genotype?phenotype correlation in pooled screening and target?identification workflows.
The host HAP1 cell line is a human male near?haploid line originally adapted from the chronic myeloid leukemia KBM?7 strain. HAP1 cells carry a modal chromosome number of approximately 25 chromosomes; the karyotype is 46,XY, with loss of one copy of most chromosomes except for chromosome 8, which remains disomic. This near?haploid architecture makes HAP1 an exceptionally tractable model for loss?of?function genetics, as single?allele disruptions suffice to generate nullizygous phenotypes. Widely used in genetic screens, drug?target validation, and signaling studies, HAP1 retains many features of myeloid cells and has been engineered for various reporter and barcoded library applications, providing a robust chassis for studying human gene function in a reductionist system.
CD163L1 encodes a type I transmembrane scavenger receptor predominantly expressed on macrophages, where it functions as the high?affinity receptor for hemoglobin?haptoglobin complexes. Ligand engagement triggers clathrin?dependent endocytosis mediated by interaction with Dab2, directing the complex to lysosomes for heme release and degradation. This process is transcriptionally activated by anti?inflammatory signals, including IL?10 and glucocorticoids, acting through STAT6 and PPAR?? to upregulate CD163L1 expression. Downstream, the liberated heme is metabolized by heme oxygenase?1 (HMOX1), yielding biliverdin, carbon monoxide, and free iron, which subsequently induces ferritin and the iron exporter ferroportin, while also promoting additional anti?inflammatory mediators such as IL?10 and ABCA1. The receptor forms functional complexes with haptoglobin and hemoglobin and collaborates with the iron transporter ZIP8 (SLC39A8) to maintain macrophage iron homeostasis. Through this axis, CD163L1 orchestrates hemoglobin clearance, iron recycling, and resolution of inflammation, favoring an M2?like macrophage polarization state.
In the HAP1 context, disruption of CD163L1 offers a unique platform to dissect scavenger?receptor trafficking and iron?handling pathways in a genetically clean background. Because HAP1 cells lack many of the compensatory pathways found in diploid macrophage models, the CD163L1 knockout population allows unambiguous assignment of phenotype to the targeted gene. The polyclonal format provides an averaged loss?of?function signature, smoothing clone?to?clone variation, and is compatible with hemoglobin?uptake assays, iron?quantification analyses, and cytokine profiling. This model facilitates investigation of how CD163L1 impacts heme?dependent signaling, endocytic sorting, and the interplay between iron metabolism and inflammatory output in a simplified human cell environment.
This product is ideal for researchers studying hemoglobin scavenging, macrophage alternative activation, and iron?related disorders such as hemolytic diseases, atherosclerosis, sepsis, and iron overload. The CD163L1 Knockout HAP1 Polyclonal Cells enable quantitative analysis of hemoglobin?haptoglobin complex internalization via flow cytometry, measurement of heme?induced HMOX1 transcription by RT?qPCR, assessment of cytokine secretion using ELISA, and genome?wide CRISPR screens to identify synthetic lethal interactions. These cells also serve as a valuable tool for screening small molecules that modulate CD163L1?dependent pathways. For further technical details, please contact Ascent Research.
