The GPAA1 Knockout Jurkat Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population designed for functional studies of GPAA1 in human T lymphocytes. Generated through CRISPR/Cas9-mediated disruption of the GPAA1 locus, this model provides a genetically diverse pool of Jurkat cells with impaired GPI transamidase activity, enabling robust investigation of GPI anchor-dependent processes. Such polyclonal pools are particularly useful for assays where population-level phenotypes are critical.
Jurkat cells are an immortalized human T lymphocyte line originally established from the peripheral blood of a 14-year-old male with acute T-cell leukemia. This widely used model system recapitulates many aspects of T-cell receptor signaling, activation, and HIV infection, making it an ideal platform for studying immune cell function. The GPAA1 knockout context in Jurkat cells allows researchers to dissect the contribution of GPI-anchored proteins to T-cell biology without the confounding effects of primary cell variability.
GPAA1 encodes the catalytic subunit of the endoplasmic reticulum-resident GPI transamidase complex, which includes the interacting subunits PIGK, PIGS, PIGT, and PIGU. This enzyme catalyzes the cleavage of C-terminal signal peptides and the concomitant attachment of preassembled GPI anchors to numerous proteins, thereby directing their cell surface expression. Key GPI-anchored proteins affected by GPAA1 disruption include the complement regulators CD55 (DAF) and CD59, as well as prion protein (PrP) and alkaline phosphatase. Upstream regulatory inputs include the ER stress sensors IRE1 and ATF6 and transcription factors YY1 and Sp1, which modulate GPAA1 expression in response to unfolded protein accumulation, positioning GPAA1 at the intersection of ER homeostasis and post-translational modification pathways.
In the Jurkat T-cell context, loss of GPAA1 function abrogates cell surface display of critical GPI-anchored proteins, including CD55 and CD59, which are essential for complement evasion and signaling microdomain organization. This impairment mimics features of paroxysmal nocturnal hemoglobinuria (PNH) and congenital disorders of glycosylation, offering a tractable model for these GPI-anchoring disorders. Consequently, GPAA1 knockout Jurkat cells serve as a powerful system to study the consequences of defective GPI anchor biosynthesis on T-cell activation, survival, and receptor-mediated signal transduction, shedding light on the molecular pathology of intellectual disability and other GPI-related conditions.
These knockout cells are ideally suited for a variety of functional assays, including flow cytometric analysis of CD55 and CD59 surface levels to quantitatively assess GPI anchoring efficiency, western blotting to evaluate GPAA1 and substrate processing, and metabolic labeling to monitor GPI anchor biosynthesis. Additionally, they can be employed in T-cell activation assays measuring IL-2 secretion or CD69 expression to determine the impact of GPI-anchored protein loss on immune responsiveness. Researchers can leverage this model to screen for small-molecule inhibitors of GPI biosynthesis or to investigate ER protein processing dynamics. This product is a valuable addition to the repertoire of gene-edited cell models for biomedical research. For further information, please contact Ascent Research.
