The FLG Knockout Raji Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout cell population derived from the Raji human Burkitt??s lymphoma B cell line. This product provides a mixed population of cells with targeted disruption of the FLG gene, without selection for a single clonal genotype. The polyclonal format reflects the heterogeneous editing outcomes characteristic of CRISPR/Cas9-based gene disruption, making it suitable for studies where a diverse knockout pool is advantageous, such as off-target analysis and population-level functional screening.
The Raji cell line is a well-established EBV-positive B lymphocyte model derived from a Burkitt??s lymphoma patient. These cells grow in suspension and are widely used in immunology and oncology research to study B cell receptor signaling, lymphomagenesis, and antibody-dependent cellular cytotoxicity. Raji cells constitutively express B cell lineage markers including CD19 and CD20, and retain many features of mature B cells, providing a robust platform for CRISPR-mediated gene editing studies even when the targeted gene is not endogenously expressed.
The FLG gene encodes profilaggrin, a polyprotein proteolytically processed into filaggrin monomers. In keratinocytes, filaggrin aggregates keratin intermediate filaments to form the cornified envelope during terminal differentiation, essential for skin barrier formation and hydration. FLG expression is regulated by transcription factors such as p63, AP-1 (c-Jun/c-Fos), and C/EBP, and is influenced by calcium and Notch pathways. Filaggrin is degraded by caspase-14 into natural moisturizing factors (amino acids, urocanic acid, pyrrolidone carboxylic acid) that maintain stratum corneum hydration and reduce transepidermal water loss. Filaggrin directly interacts with keratins and cross-linking proteins like loricrin and involucrin via transglutaminase reactions, forming a resilient barrier.
Although FLG is not typically expressed in B lymphocytes, this polyclonal knockout cell population provides a critical tool for validating CRISPR/Cas9 editing efficiency and specificity in a hematopoietic context. The Raji background allows assessment of off-target events and optimization of guide RNA design without endogenous FLG confounding. Moreover, these cells serve as a negative control for FLG-dependent studies in keratinocytes or epithelial systems, and may reveal non-canonical profilaggrin functions in immune cells. The polyclonal nature enables analysis of editing outcome diversity, aiding robust protocol development.
Key research applications include CRISPR editing validation through Sanger sequencing of the FLG locus, T7E1 mismatch detection assays, and comprehensive off-target sequencing. Users can characterize the heterogeneity of the knockout population by next-generation sequencing and correlate editing genotypes with phenotypic assays such as flow cytometry for B cell markers (CD19, CD20). Additionally, these cells can be used to optimize nucleofection conditions and guide RNA sequences for high-efficiency editing in suspension lymphoblastoid cells. For studies requiring induced FLG expression, the knockout background provides a blank slate for transgenic complementation experiments. For further technical details or to discuss custom validation needs, please contact Ascent Research.
