The GC Knockout Raji Polyclonal Cells consist of a CRISPR/Cas9-edited pool of Raji cells harboring heterogeneous disruptions in the GC gene, which encodes the vitamin D-binding protein (DBP). As a polyclonal population, the product offers a genetically diverse loss-of-function model free from clonal selection artifacts, enabling robust interrogation of GC function in a B lymphoblast background without imposing a single uniform mutation.
Raji cells are Epstein-Barr virus-immortalized B lymphoblasts originally derived from a Burkitt??s lymphoma patient. They express canonical B cell markers CD19, CD20, and CD22 and are widely employed as a model system for B cell malignancies, EBV biology, and humoral immunity. Their rapid growth and ease of genetic manipulation make them well-suited for CRISPR-based gene disruption studies.
The GC-encoded DBP is a serum protein that binds and transports vitamin D metabolites, including 25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3. Uptake into cells is facilitated by megalin/cubilin receptors, whereupon DBP releases its cargo to bind the vitamin D receptor (VDR). VDR then dimerizes with RXR and transcriptionally regulates genes such as CYP24A1 and targets involved in immune cell differentiation. DBP also acts as an extracellular actin scavenger, preventing actin polymerization-induced toxicity, and can be converted to a macrophage-activating factor (MAF) that stimulates innate immunity. Upstream, GC expression is modulated by VDR signaling itself, as well as by IL-6, TNF-alpha, and glucocorticoids. The GC protein interacts with vitamin D metabolites, actin, C5a, and fatty acids, positioning it at the nexus of endocrine and immune signaling.
Loss of DBP in Raji cells disrupts the local transport and bioactivation of vitamin D metabolites, potentially altering VDR-driven gene programs that influence B cell proliferation, differentiation, and apoptosis. Additionally, abrogation of actin scavenging may sensitize cells to actin-mediated cytotoxicity, which is relevant to lymphoma pathology. The polyclonal knockout design captures a spectrum of mutational effects, providing a more physiologically relevant platform to study DBP??s role in B cell biology than a single clonal isolate.
Applications include vitamin D metabolism studies, immune cell function assays, and cancer biology research. GC disruption can be confirmed by Western blotting or RT-qPCR, while ELISA quantifies secreted DBP. Flow cytometry for CD19/CD20 validates B cell identity, and actin binding assays or co-immunoprecipitation assess the actin-scavenging function. Macrophage activation assays using conditioned medium enable studies of MAF production. The cells are also suitable for migration and chemotaxis experiments. For further technical information, please contact Ascent Research.
