Interleukin 2r Antibody
Description
Definition and Target
IL-2R antibodies bind to the α-subunit (CD25) of the high-affinity IL-2 receptor expressed on activated T cells . The IL-2 receptor comprises three subunits:
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CD25 (α): Low-affinity binding site, upregulated on activated T cells.
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CD122 (β) and CD132 (γ): Shared with other cytokine receptors, enabling signal transduction .
By blocking CD25, these antibodies prevent IL-2 from initiating downstream signaling, thereby suppressing T-cell proliferation .
Mechanism of Action
IL-2R antibodies function through competitive inhibition:
This selective action minimizes broad immunosuppression, reducing infection risks compared to traditional agents like calcineurin inhibitors .
Transplant Rejection Prevention
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Renal transplantation: Meta-analysis of 8 RCTs (1,858 patients) showed IL-2R antibodies reduced acute rejection by 48% (OR 0.51, 95% CI 0.42–0.63) .
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Pediatric use: Basiliximab and daclizumab are safe in children, with no increased malignancy risk .
Autoimmune Diseases
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Systemic lupus erythematosus (SLE): Low-dose IL-2 expanded Tregs but faced mixed clinical outcomes in trials .
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Primary Sjögren’s syndrome (pSS): A 2022 RCT (n=60) reported 66.7% of patients achieved ≥3-point ESSDAI improvement vs. 26.7% with placebo (P=0.004) .
Key Outcomes in Renal Transplantation (Meta-Analysis)
| Endpoint | IL-2R Antibody Group | Control Group | Odds Ratio (95% CI) |
|---|---|---|---|
| Acute rejection (6 months) | 25.7% | 39.6% | 0.51 (0.42–0.63) |
| Graft loss (1 year) | 12.1% | 14.5% | 0.78 (0.58–1.04) |
| Mortality (1 year) | 3.2% | 4.1% | 0.75 (0.46–1.23) |
No significant differences in infections (OR 0.97) or cytomegalovirus reactivation (OR 0.81) .
Engineered IL-2/Antibody Complexes
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SAR444336: A CD25-biased IL-2 variant with extended half-life and Treg selectivity .
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UFKA-20 fusion: Covalently linked IL-2/antibody complex reduces off-target activation, showing efficacy in ulcerative colitis and SLE models .
Clinical Trials in Autoimmunity
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Steroid-refractory GVHD: Low-dose IL-2 achieved 53.3% response rates in chronic GVHD .
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Ulcerative colitis: IL-2/antibody fusions suppressed humoral immunity and disease progression in preclinical models .
Limitations and Challenges
Product Specs
Product Science Overview
The Interleukin-2 receptor (IL-2R), also known as CD25, is a critical component of the immune system. It plays a pivotal role in the regulation of immune responses by mediating the effects of interleukin-2 (IL-2), a cytokine that promotes the growth, differentiation, and survival of T cells. The IL-2 receptor is composed of three subunits: alpha (IL-2Rα or CD25), beta (IL-2Rβ), and the common gamma chain (IL-2Rγ). The high-affinity IL-2 receptor is formed by the assembly of these three subunits .
CD25, the alpha chain of the IL-2 receptor, is a 55 kDa protein that binds IL-2 with low affinity on its own. However, when combined with the beta and gamma chains, it forms a high-affinity receptor complex. This receptor complex is essential for the IL-2-mediated signaling pathways that regulate T cell proliferation and differentiation .
CD25 is constitutively expressed at high levels on regulatory T cells (Tregs) and transiently on activated effector T cells (Teff). The expression of CD25 is a hallmark of Treg cells, which play a crucial role in maintaining immune tolerance and preventing autoimmune diseases .
The rat anti-mouse CD25 antibody is a monoclonal antibody that specifically targets the CD25 molecule on mouse cells. This antibody is commonly used in immunological research to study the expression and function of CD25 in various mouse models. It is particularly useful in flow cytometry, immunohistochemistry, and other immunoassays to identify and isolate CD25-expressing cells .
One of the widely used clones of rat anti-mouse CD25 antibody is PC61. This clone has been extensively characterized and is known for its high specificity and affinity for mouse CD25. The PC61 antibody can be conjugated to various fluorochromes or enzymes to facilitate its detection in different experimental setups .
The rat anti-mouse CD25 antibody has several important applications in immunological research:
- Flow Cytometry: It is used to analyze the expression of CD25 on different subsets of T cells, including Tregs and Teff cells. This helps in understanding the dynamics of immune responses and the role of CD25 in T cell activation and regulation .
- Immunohistochemistry: The antibody can be used to stain tissue sections and visualize the distribution of CD25-expressing cells in various organs. This is valuable for studying the localization and function of Tregs in different tissues .
- Functional Studies: By blocking or depleting CD25-expressing cells using the rat anti-mouse CD25 antibody, researchers can investigate the role of these cells in immune responses and disease models. This approach is commonly used to study the function of Tregs in autoimmune diseases, cancer, and transplantation .
