Active Recombinant Human EFNB3 protein, Fc/His-Tagged, Biotinylated

• Cat.No.: EFNB3-713H
• Product Overview: Biotinylated Recombinant Human EFNB3 protein(Q15768)(Leu28-Ser224), fused with C-terminal Fc and His Tag, was expressed in Insect Cells.

Specification

• Species: Human
• Source: Insect Cells
• Tag: Fc&His
• Protein Length: Leu28-Ser224
• Form: Lyophilized from a 0.2 μm filtered solution in PBS with BSA as a carrier protein.
• Bio-activity: Measured by its binding ability in a functional ELISA. Immobilized recombinant mouse EphB3 Fc Chimera at 2 μg/mL (100 μL/well) can bind biotinylated Recombinant Human Ephrin‑B3 Fc Chimera with a linear range of 1.3-80 ng/mL.
• Molecular Mass: 49.2 kDa (monomer)
• Purity: >95%, by SDS-PAGE under reducing conditions and visualized by silver stain
• Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  12 months from date of receipt, -20 to -70 °C as supplied.
  1 month, 2 to 8 °C under sterile conditions after reconstitution.
  3 months, -20 to -70 °C under sterile conditions after reconstitution.
• Reconstitution: Reconstitute at 100 μg/mL with sterile PBS.
• Conjugation: Biotin

Gene Information

• Gene Name: EFNB3 ephrin-B3 [ Homo sapiens ]
• Official Symbol: EFNB3
• Synonyms: EFNB3; ephrin-B3; EPLG8; LERK 8; Ephrin B3; eph-related receptor tyrosine kinase ligand 8; EPH-related receptor transmembrane ligand ELK-L3; EFL6; LERK8
• Gene ID: 1949
• mRNA Refseq: NM_001406
• Protein Refseq: NP_001397
• MIM: 602297
• UniProt ID: Q15768

Case Study

Case 1: Prydz K, et al. Biochem Biophys Res Commun. 2018

Ephrin-B3 binds secretory/cell-associated proteoglycans (e.g., CD44, agrin) via a 20/45 kDa protein complex, modulating extracellular matrix interactions in cancer metastasis. CD44 variants regulate binding affinity, suggesting therapeutic targets for oral squamous carcinoma and Eph receptor signaling dysregulation.

Fig1. Ephrin-B3-binding proteoglycans.

Fig2. Heparin blocks ephrin-B3 binding to H367 cells.

Case 2: Holen HL, et al. Scand J Immunol. 2011

Ephrin-B3 binds B lymphocytes via a heparin-sensitive, Arg-188-dependent non-Eph receptor, selectively driving memory B-cell migration—a novel mechanism for modulating immune responses and leukocyte trafficking in autoimmune or lymphoma therapies.

Fig1. Detection of cell surface proteins binding ephrin-B3.

Fig2. Ephrin-B3 enhances migration of memory CD19+ B cells.

Application

1. Therapeutic Potential of Recombinant EFNB3 Protein in Neuroprotection and Oncology Recombinant ephrin-B3 (EFNB3) protein, a critical Eph receptor ligand, demonstrates dual therapeutic utility in neuroprotection and cancer therapy. In neurodegenerative contexts, EFNB3 mitigates glutamate excitotoxicity by restoring astrocytic EAAT1/2 function, counteracting HIV Tat-induced neuronal damage. In oncology, it suppresses glioma and lung adenocarcinoma progression by inhibiting Eph receptor-driven PI3K/AKT and ERK pathways, reducing tumor migration and metastasis. 2. Mechanistic Insights and Preclinical Applications Preclinical studies reveal EFNB3’s ability to modulate EphA4 signaling, enhancing glutamate uptake in astrocyte-neuron co-cultures and improving neuronal survival in neuroHIV models. In cancer, EFNB3 destabilizes focal adhesions and downregulates MMP-2/9, impairing invasion. Rodent glioma models show EFNB3 overexpression reduces tumor volume by 40% and prolongs survival, while synergizing with immune checkpoint inhibitors to enhance T-cell infiltration. 3. Delivery Challenges and Future Innovations Current limitations include poor CNS bioavailability and transient activity. Emerging solutions include engineered exosomes for blood-brain barrier penetration and CRISPR-activation systems for sustained EFNB3 expression. Combining EFNB3 with antiretroviral therapies or CAR-T cells could address neurocognitive disorders and therapy-resistant cancers, positioning it as a versatile candidate for precision medicine.

Fig1. Model of the mechanism of guidance and migration of SC after CNS demyelination. (Beatriz Garcia-Diaz, 2019)