The OTUD5 Knockout Raji Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout population derived from the human Raji B lymphocyte line. They feature targeted disruption of OTUD5, ablating functional deubiquitinase (DUBA). The polyclonal format provides a heterogeneous cell pool that avoids clonal bias and better mimics primary immune cell variability. This loss-of-function model suits researchers studying OTUD5 in a well-characterized B cell context.
Raji cells are an EBV-positive Burkitt lymphoma B lymphocyte line widely used for humoral immunity and antibody production studies. They retain key B cell features, serving as a robust model for B cell activation, proliferation, and immune signaling. Their viral association also facilitates host-pathogen interaction and oncogenesis research, providing a physiologically relevant system for OTUD5 investigation.
OTUD5 is a deubiquitinase that negatively regulates type I interferon signaling by deubiquitinating TRAF3 and TRIM25, essential adaptors in the RIG-I-like receptor (RLR) pathway. Upon viral RNA sensing by RIG-I and MAVS, TRAF3 and TRIM25 are ubiquitinated, propagating signals via TBK1 and IKK?? to phosphorylate IRF3/IRF7, inducing IFN-?? and ISGs. OTUD5 removes K63-linked ubiquitin chains from these substrates, attenuating the cascade and serving as a critical checkpoint. Its expression is induced by type I interferon and JAK-STAT, forming a negative feedback loop. OTUD5 also intersects with Toll-like receptor, NF-??B, and DNA damage pathways, and deubiquitinates p53, connecting innate immunity to tumor suppression.
In Raji polyclonal knockout cells, loss of OTUD5 removes this inhibitory brake, leading to heightened and sustained ubiquitination of TRAF3 and TRIM25 upon pathway stimulation. Consequently, downstream TBK1/IKK?? activation, IRF3/IRF7 phosphorylation, and type I interferon production are expected to be amplified. Given Raji??s B lymphocyte identity and EBV positivity, this model is particularly valuable for exploring how dysregulated deubiquitinase activity influences antiviral innate immunity, autoinflammatory responses, and B cell malignancies. The polyclonal nature minimizes artifacts from clonal adaptation, making the population more representative of in vivo heterogeneity and suitable for functional screens and drug testing.
Researchers can employ diverse techniques to characterize this knockout model. Western blotting monitors OTUD5 ablation, TRAF3/TRIM25 expression, and IRF3 phosphorylation; RT-qPCR quantifies IFN-?? and ISG transcripts; co-immunoprecipitation reveals TRAF3 ubiquitination; immunofluorescence tracks IRF3 nuclear translocation. Functional assays include dual-luciferase IFN-?? promoter reporters, ELISA for secreted IFN-??, and flow cytometry for B cell markers. The cells support transfection and viral infection for reconstitution and mechanistic studies. Applications encompass innate immunity, autoimmunity modeling (e.g., SLE), cancer immunotherapy, and antiviral research. For inquiries, contact Ascent Research.
