The EXPH5 Knockout Raji Polyclonal Cells represent a CRISPR/Cas9-edited polyclonal knockout population of the human Raji B lymphoblastoid cell line, designed for loss-of-function studies of the exophilin-5 (EXPH5) gene. This product comprises a heterogeneous pool of cells carrying targeted disruptions in the EXPH5 locus, generated via CRISPR/Cas9-mediated gene disruption. The polyclonal format enables robust functional analyses without clonal selection, providing a model system to investigate the roles of EXPH5 in vesicle trafficking, exosome secretion, and B cell immune functions.
The Raji cell line is a well-characterized human Burkitt lymphoma B lymphocyte model, established from a patient with Epstein-Barr virus (EBV)-positive lymphoma. Raji cells exhibit a mature B cell phenotype, expressing characteristic surface markers such as CD19 and CD20, but lack surface immunoglobulin. They are widely employed in immunology and cancer research for studies of B cell signaling, immune complex binding, and lymphomagenesis. The EBV-positive background makes Raji cells particularly relevant for examining viral interactions with host cellular machinery, including exosome biogenesis and intercellular communication.
Exophilin-5, encoded by EXPH5, functions as a critical Rab27 effector linking Rab27-positive vesicles to the actin cytoskeleton via myosin Va and myosin VIIa. This facilitates transport, tethering, and fusion of secretory lysosomes and exosomes at the plasma membrane. Upstream regulators include Rab27A, Rab27B, and calcium signaling; downstream components involve the exocyst complex and SNARE proteins SNAP23 and VAMP7, with ??-actin as a structural anchor. EXPH5 operates within exosome biogenesis and lysosomal exocytosis pathways, coordinating extracellular vesicle release. Disruption of EXPH5 impairs these actin-dependent trafficking events, providing insight into Rab27-mediated vesicular dynamics.
In Raji B cells, EXPH5 knockout is anticipated to reduce exosome secretion and lysosomal exocytosis, impairing intercellular communication mediated by extracellular vesicles. B cells use exosomes for antigen presentation and immune modulation; loss of exophilin-5 may perturb these processes, offering a model to study Rab27 effector functions in hematologic cells. EXPH5 has been implicated in epidermolysis bullosa simplex and may contribute to cancer immune evasion through exosome-dependent mechanisms, making this knockout relevant for disease research in a B lymphocyte background.
Research applications include investigation of B cell exosome biogenesis and immune modulation, functional analysis of Rab27 effectors in hematopoietic cells, and exploration of exosome-mediated pathogenesis in lymphoma. The cells support assays such as Western blotting and RT-qPCR for EXPH5, immunofluorescence and flow cytometry for exosome and lysosomal markers, nanoparticle tracking and electron microscopy for exosome characterization, co-immunoprecipitation of EXPH5?CRab27 complexes, and exosome secretion assays upon stimulation. For further details or custom configurations, please contact Ascent Research.
