Natural killer (NK) cells have recently been at the forefront of many immunotherapy strategies, with new methods being developed to fully exploit their anti-tumor potential. NK cells play a pivotal role in tumor immunity and are increasingly becoming a frontier area in immunotherapy strategies. Numerous novel compounds, including monoclonal antibodies, are under development to maximize their anti-tumor capabilities. Additionally, adoptive therapies involving NK cells, such as allogeneic NK cells and CAR-NK cells, have achieved notable success. CAR-NK cells offer several distinct advantages over CAR-T cells, including their short lifespan and minimal off-target effects. Furthermore, the cytokines produced by NK cells differ significantly from those produced by T lymphocytes. Active NK cells typically secrete IFN-γ and GM-CSF, avoiding the cytokine storms often induced by CAR-T cells. FITC-labeled NKG2D/CD314 Fc chimera protein can be used to quantitatively assess NKG2D protein expression levels and ligand-binding activity, providing a technical tool for NK cell functional studies.
One of the most relevant NK cell activation receptors is NKG2D, which recognizes eight distinct NKG2D ligands, including MICA and MICB. MICA and MICB are expressed at low levels on normal cells but are upregulated on the surface of damaged, transformed, or infected cells. Their binding to NKG2D triggers NK cell effector functions. Moreover, MICA and MICB are polymorphic, and this polymorphism influences functional responses by modulating their cell surface expression, intracellular trafficking, shedding of immunosuppressive soluble forms, or affinity for NKG2D interactions. In humans, eight different NKG2DLs have been identified. MICA is expressed in various tumors, with RNA sequencing data indicating its highest expression in lung, colorectal, gastric, liver, and breast cancers. FITC-labeled NKG2D/CD314 Fc chimera protein can be used to study the interaction between NKG2D and its ligands, providing quantitative data support for target validation.
NK cells can act as drivers of tumor inflammation, leading to immune cell infiltration and facilitating the transformation of "cold" tumors into "hot" tumors, thereby enhancing responsiveness to immune checkpoint inhibitors. The key function of NK cells in inducing effective tumor immunity depends on successful crosstalk with dendritic cells and the production of chemokines CCL5 and XCL1. Tumor-derived prostaglandin E2 interferes with this mutual stimulation. TGF-β is a major negative regulator of NK cell effector functions. In vitro studies show that TGF-β and MMP-generated autocrine loops promote the shedding of MICA and ULBP-2, negatively impacting the expression of these NKG2DLs on tumor cell surfaces. TGF-β also suppresses the expression of NKp30 and NKG2D on NK cells and affects NK cell metabolism, reducing glycolysis and oxidative phosphorylation, thereby inhibiting NK cell effector functions. Tumor-associated macrophages also contribute to tumor immune evasion, and targeting them can restore NK cell activation and effector functions to improve tumor immunity.
Inhibitory receptors, exemplified by the PD-1/PD-L1 axis, constitute immune checkpoints and have become a forefront research focus. These receptors are often overexpressed in dysfunctional NK cells. Growing evidence indicates that NK cells also express PD-1 and PD-L1, and targeting them can restore the effector functions of anti-tumor NK cells. Increased frequencies of PD-1-positive NK cells and enhanced PD-1 expression have been observed in circulating and tumor-infiltrating NK cells from patients with various gastrointestinal tumors. TIGIT is a co-inhibitory receptor overexpressed on exhausted tumor-infiltrating NK and T cells, and blocking TIGIT can reinvigorate NK cells. CD96 is another co-inhibitory receptor expressed on NK cells that limits NK cell effector functions by binding to CD155 expressed on tumor cells. NKG2A is another inhibitory receptor associated with CD94, and blocking NKG2A with anti-NKG2A monoclonal antibodies enhances tumor immunity by promoting NK and CTL effector functions when combined with anti-PD-L1 immune checkpoint inhibitors.
MICA, a widely expressed NKG2DL in tumors, holds promise as a target for immuno-oncology strategies. Antibody-dependent cellular cytotoxicity (ADCC) is one of the primary effector functions mediated by NK cells, and developing MICA-targeting monoclonal antibodies leveraging NK cell-mediated ADCC is a key strategy. Some anti-MICA monoclonal antibodies have shown promising preclinical results, with MICA-targeting antibodies, either alone or in combination with anti-CTLA-4 monoclonal antibodies, demonstrating therapeutic effects. Other anti-MICA/B monoclonal antibodies targeting the α3 domain inhibit proteolytic shedding, delaying the growth of melanoma and colon cancer in mice. CAR-T or CAR-NK cells can also target NKG2DLs. Engineered CAR-T cells expressing NKG2D have been developed, exhibiting enhanced effector functions against cell lines and xenografted human or syngeneic mouse tumor cell lines. FITC-labeled NKG2D/CD314 Fc chimera protein can be used to evaluate the binding capacity of CAR-T cells to NKG2D ligands, validating their functional activity.
Nanjing UA-Bio Technology Co., Ltd. (UA-Bio) has independently developed "FITC-Labeled NKG2D/CD314 Fc Chimera Protein, Human" (Catalog No.: UA011263), a high-performance green fluorescent-labeled probe specifically designed for NKG2D-targeted research and tumor immunotherapy evaluation. NKG2D (also known as CD314) is a key activating receptor on the surface of NK and T cells, playing a critical role in tumor immune surveillance. This protein is a chimera of the human NKG2D extracellular domain fused with the human IgG Fc fragment and labeled with FITC fluorescence. It efficiently binds to natural NKG2D ligands (e.g., MICA, MICB, ULBP family) or anti-NKG2D antibodies, providing a stable and reliable standardized tool for CAR-NK cell therapy evaluation, antibody drug screening, and tumor immune microenvironment research.
| Core Product Advantages | Detailed Parameters / Functional Description |
|---|---|
| High Purity and Intact Bioactivity | The product utilizes an advanced eukaryotic expression system and highly standardized purification processes, validated through multi-dimensional quality control to ensure >95% purity and correct native conformation (with intact glycosylation). The Fc chimera format enhances protein stability and proper folding. The FITC labeling process is optimized to maintain high labeling efficiency while preserving NKG2D's high-affinity binding to natural ligands, accurately simulating the immune activation process mediated by NKG2D under physiological conditions.-- |
| High-Brightness FITC Labeling | An optimized FITC labeling ratio ensures stable fluorescence dye conjugation per NKG2D-Fc chimera molecule, emitting bright green fluorescence under 488 nm excitation. This makes it suitable for flow cytometry (FACS) and fluorescence microscopy, providing reliable support for the activity evaluation and precise quantification of NKG2D-targeted molecules.-- |
| Versatile Tool for Multiple Applications | This protein excels in various applications, including CAR-NK cell positivity rate assessment by flow cytometry, anti-NKG2D antibody/antagonist screening, ligand-receptor binding analysis (e.g., MICA/NKG2D interaction studies), competitive binding assays, tumor immune microenvironment analysis, and flow cytometry. It is widely applicable to CAR-NK cell therapy product development, tumor immunotherapy research, and drug activity evaluation.-- |
| Comprehensive Solutions and Professional Support | We provide thoroughly validated standard protocols, exemplary flow cytometry data, and detailed interpretation guides to help establish stable and reproducible NKG2D-targeted molecule detection workflows. Nanjing UA-Bio's technical team offers end-to-end professional consultation and support for research design, experimental optimization, and data analysis.-- |
Nanjing UA-Bio Technology Co., Ltd. is committed to providing cutting-edge, high-quality core reagents and tools for immunology, cell therapy, and innovative drug development. For detailed technical parameters, validation data, or application inquiries regarding "FITC-Labeled NKG2D/CD314 Fc Chimera Protein, Human" (Catalog No.: UA011263), please feel free to contact us.
