APOA1 knockout HEK293T polyclonal cells are a CRISPR/Cas9-edited cell population with targeted disruption of the APOA1 gene, encoding apolipoprotein A-I, the primary protein component of high-density lipoprotein (HDL). This polyclonal knockout model eliminates apoA-I expression, providing a heterogeneous loss-of-function system for studying HDL biology and reverse cholesterol transport. The cells are supplied as a mixed population, reflecting diverse CRISPR-induced edits, and are suitable for applications requiring abolition of apoA-I function without clonal selection.
The host cell line, HEK293T, is a human embryonic kidney epithelial line that constitutively expresses the SV40 large T antigen, conferring high transfection efficiency and robust episomal plasmid replication. Derived from the HEK293 lineage, these cells are widely utilized for protein expression, viral production, and genetic manipulation. Their epithelial phenotype and endogenous expression of relevant membrane transporters and receptors make them a practical model for studying lipid handling pathways, although they are not of hepatic or macrophage origin.
ApoA-I is integral to reverse cholesterol transport, promoting cellular cholesterol efflux through interaction with ATP-binding cassette transporter A1 (ABCA1) and activating lecithin-cholesterol acyltransferase (LCAT) for cholesterol esterification on nascent HDL. Upstream, APOA1 transcription is regulated by nuclear receptors including PPAR?? (fibrates), LXR?? (oxysterols), and RXR, as well as HNF4?? and estrogen receptor. Downstream, mature HDL particles interact with scavenger receptor class B type I (SR-BI) for selective lipid uptake and with cholesteryl ester transfer protein (CETP) for lipid exchange. Other interacting factors include phospholipid transfer protein (PLTP) and apolipoproteins A-II and E. Disruption of APOA1 impairs ABCA1-dependent efflux, LCAT activation, and HDL assembly, disrupting cellular cholesterol homeostasis.
In HEK293T cells, APOA1 knockout eliminates the major apolipoprotein acceptor for cholesterol, preventing ABCA1-mediated efflux to lipid-poor apoA-I and blocking formation of nascent HDL particles. This results in altered intracellular cholesterol distribution and diminished capacity for reverse cholesterol transport, providing a clean background to study apoA-I-specific functions. The model enables dissection of HDL biogenesis steps independent of confounding factors from other lipoprotein pathways, facilitating investigation of how apoA-I influences lipid raft composition, membrane fluidity, and cellular signaling networks in a human kidney epithelial context.
Typical applications include HDL particle assembly studies, cholesterol efflux assays using BODIPY-cholesterol, and reverse cholesterol transport pathway analysis. The knockout cells support drug screening for HDL-raising agents, apoA-I mimetics, and investigations into the anti-inflammatory roles of apoA-I. Common readouts comprise western blotting for apoA-I, RT-qPCR, LCAT activity measurements, ABCA1 surface detection by flow cytometry, and transcriptomic profiling via RNA-seq. For further information, please contact Ascent Research.
