ULBP2 Human, Sf9
Description
Functional Mechanisms:
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NKG2D Activation: Binds NKG2D with high affinity (ED50: 7.5–60 ng/mL in binding assays) .
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Immune Evasion by Pathogens: Cytomegalovirus glycoprotein UL16 retains ULBP2 in the endoplasmic reticulum, preventing surface expression .
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Dual Signaling: Engages JAK2/STAT5, ERK, and PI3K/Akt pathways in NK cells .
Production and Quality Control
ULBP2 Human, Sf9 is synthesized via baculovirus-mediated expression, followed by chromatographic purification using its C-terminal His-tag .
Critical Production Metrics:
| Parameter | Details |
|---|---|
| Expression Yield | ~0.5 mg/mL post-purification |
| Endotoxin Levels | <1 EU/μg (LAL assay) |
| Stability | Stable at -20°C for 12 months; avoid freeze-thaw cycles (carrier proteins recommended) |
4.1. Cancer Immunotherapy
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ULBP2 is overexpressed in colon, ovarian, and breast cancers, correlating with NK cell infiltration and improved prognosis .
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Preclinical studies use recombinant ULBP2 to enhance NK cell-mediated tumor lysis .
4.2. Viral Immune Evasion
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CMV infection downregulates ULBP2 surface expression via UL16-mediated ER retention, a mechanism exploited for immune evasion .
4.3. Small-Molecule Targeting
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Recent studies identify small-molecule inhibitors (e.g., compound 3b) blocking NKG2D/ULBP2 interaction (IC50: 2.2 μM) .
Challenges and Future Directions
Product Specs
Product Science Overview
UL16 Binding Protein 2 (ULBP2) is a member of the UL16-binding protein family, which are ligands for the NKG2D receptor. These proteins play a crucial role in the immune response, particularly in the recognition and destruction of tumor cells by natural killer (NK) cells and certain T cells. ULBP2 is a glycoprotein that is frequently expressed on the surface of malignant cells and can stimulate anti-tumor immune responses.
ULBP2, like other members of the ULBP family, is structurally related to MHC class I molecules. It contains α1 and α2 domains but lacks the α3 domain and the transmembrane region found in classical MHC class I molecules . This structural configuration allows ULBP2 to interact with the NKG2D receptor on NK cells and certain T cells, triggering their cytotoxic activity against target cells.
ULBP2 expression is typically induced by cellular stress, such as infection or transformation into a malignant state . This makes it a valuable marker for the immune system to identify and target abnormal cells. The expression of ULBP2 can be regulated by various factors, including cytokines and cellular stress signals.
The recombinant form of ULBP2 is often produced using the Sf9 insect cell line, which is derived from the fall armyworm Spodoptera frugiperda. This system is widely used for the production of recombinant proteins due to its ability to perform post-translational modifications similar to those in mammalian cells. The recombinant ULBP2 produced in Sf9 cells retains its functional properties and can be used for various research and therapeutic applications.
ULBP2 plays a significant role in immune surveillance by binding to the NKG2D receptor on NK cells and certain T cells . This interaction activates these immune cells, leading to the destruction of the target cells expressing ULBP2. This mechanism is particularly important in the context of tumor immunity, where the immune system needs to recognize and eliminate cancerous cells.
The expression of ULBP2 on tumor cells and its ability to activate immune responses make it a potential target for cancer immunotherapy. Strategies that enhance the expression of ULBP2 on tumor cells or block its shedding from the cell surface could improve the effectiveness of immune-based treatments . Additionally, measuring soluble ULBP2 levels in the serum of cancer patients could serve as a biomarker for disease progression and response to therapy.
