IL21R Mouse
Description
Genetic Characteristics of IL21R Mice
IL21R mice are typically generated through targeted gene editing to disrupt or humanize the murine Il21r gene. Key features include:
| Strain Name | Genetic Modification | Strain Background | NCBI Gene ID | Aliases |
|---|---|---|---|---|
| B-hIL21R mice | Humanized exons 3-6 of Il21r (extracellular domain) | C57BL/6 | 60504 | CD360, NILR |
Mechanism:
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Humanization: Replacing critical exons (3-6) of the mouse Il21r gene with human equivalents enables studies of cross-species IL-21 interactions .
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Knockout (KO): Deletion of Il21r exons disrupts receptor function, allowing analysis of IL-21R deficiency in immune responses .
Physiological Roles of IL21R in Mice
IL21R is a type I cytokine receptor that forms a heterodimer with the common gamma-chain (γc). Its activation triggers downstream signaling via JAK/STAT pathways, influencing immune cell development and function.
Key Functions:
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B Cell Development:
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T Cell and NK Cell Activity:
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Macrophage and Dendritic Cell Function:
Applications in Research
IL21R mice are pivotal for studying immune-mediated diseases and developing therapeutic interventions.
Disease Models and Findings:
Therapeutic Implications
IL21R blockade or agonism has potential in treating autoimmune diseases and cancer:
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Autoimmune Diseases: Targeting IL21R may suppress pathogenic Th1/Th17 responses while enhancing Treg function .
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Infectious Diseases: IL21R agonists could enhance antimicrobial immunity by boosting IFN-γ+ T cells .
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Cancer: IL21R signaling in CD8+ T cells may improve tumor control, though overactivation risks inflammation .
Recombinant IL21R-Fc fusion proteins (e.g., mouse IL21R Fc chimera) and monoclonal antibodies (e.g., 4A9) are tools for in vivo IL21R modulation .
Research Challenges and Considerations
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Strain-Specific Variability: C57BL/6 and other backgrounds may influence immune phenotypes in IL21R KO models .
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Humanization vs. Knockout: Humanized models (e.g., B-hIL21R) are ideal for testing human IL-21 therapeutics, while KO models reveal endogenous IL-21R functions .
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Compensatory Mechanisms: IL21R KO mice may exhibit altered signaling via related γc-dependent cytokines (e.g., IL-2, IL-15) .
Product Specs
Interleukin-21 (IL-21) is a cytokine primarily produced by activated CD4+ T cells that plays a crucial role in regulating immune responses. It exerts its effects by binding to the IL-21 receptor (IL-21R), a heterodimeric receptor complex expressed on various immune cells, including B cells, T cells, and natural killer (NK) cells. IL-21 binding to its receptor initiates intracellular signaling cascades, leading to the activation of downstream signaling pathways, such as JAK/STAT pathway, ultimately influencing cell proliferation, differentiation, and effector functions. IL-21 exhibits pleiotropic effects on both innate and adaptive immune responses. It is involved in the differentiation of B cells into antibody-producing plasma cells, enhances antibody production, and supports the development of memory B cells, thereby contributing to humoral immunity. IL-21 also promotes the cytotoxic activity of CD8+ T cells and NK cells, enhancing their ability to eliminate virus-infected cells and tumor cells. Moreover, IL-21 plays a role in regulating T cell differentiation and function, influencing the balance between effector and regulatory T cell subsets. Given its multifaceted roles in immune regulation, IL-21 has been implicated in the pathogenesis of various autoimmune diseases, inflammatory disorders, and cancers. Targeting IL-21 or its receptor has emerged as a potential therapeutic strategy for modulating immune responses in these conditions.
IL-21R Mouse Recombinant is a genetically engineered protein produced in HEK293 cells, a human embryonic kidney cell line widely used for protein expression. This recombinant protein consists of the extracellular domain of mouse IL-21R fused to a human IgG-His-Tag at the C-terminus. The extracellular domain of IL-21R is responsible for binding to IL-21, while the human IgG-His-Tag facilitates protein purification and detection. The protein has a molecular weight of approximately 52 kDa, and it appears as a colorless solution after sterile filtration. The purity of the protein is greater than 95% as determined by SDS-PAGE analysis.
Sterile, clear, and colorless solution.
The IL21R protein solution is provided at a concentration of 0.25 mg/ml in a buffer containing phosphate-buffered saline (PBS) at pH 7.4 and 10% glycerol. PBS provides a physiologically relevant pH and salt concentration, while glycerol acts as a cryoprotectant, preventing protein degradation during freezing and thawing.
For short-term storage (up to 4 weeks), the IL21R solution should be stored at 4°C. For long-term storage, it is recommended to store the protein at -20°C. To ensure optimal stability during long-term storage, it is advisable to add a carrier protein such as 0.1% human serum albumin (HSA) or bovine serum albumin (BSA) to the solution. Carrier proteins help to prevent protein aggregation and degradation. It is crucial to avoid repeated freezing and thawing of the IL21R solution, as this can lead to protein denaturation and loss of activity.
The purity of the IL21R Mouse Recombinant protein is greater than 95%, as determined by SDS-PAGE analysis. This high level of purity ensures the reliability and consistency of experimental results.
The biological activity of the IL21R Mouse Recombinant protein is measured by its ability to inhibit interferon-gamma (IFN-γ) secretion by NK-92 human natural killer cells in the presence of mouse IL-2. The ED50 value, which represents the effective dose of the protein required to inhibit IFN-γ secretion by 50%, is less than or equal to 4 µg/ml. This assay demonstrates the functional activity of the recombinant IL21R protein in inhibiting IL-21 signaling.
Interleukin-21 receptor, IL-21 receptor, IL-21R, Il21r, Lymphocyte receptor beta, LR-beta, Novel interleukin receptor, Novel cytokine receptor 8, NR8, Novel interleukin receptor, CD360, CD360 antigen, NILR, Nilr.
HEK293 Cells.
CLDLTCYTDY LWTITCVLET RSPNPSILSL TWQDEYEELQ DQETFCSLHR SGHNTTHIWY TCHMRLSQFL SDEVFIVNVT DQSGNNSQEC GSFVLAESIK PAPPLNVTVA FSGRYDISWD SAYDEPSNYV LRGKLQYELQ YRNLRDPYAV RPVTKLISVD SRNVSLLPEE FHKDSSYQLQ VRAAPQPGTS FRGTWSEWSD PVIFQTQAGE PEAGWDPHLE PKSCDKTHTC PPCPAPELLG GPSVFLFPPK PKDTLMISRT PEVTCVVVDV SHEDPEVKFN WYVDGVEVHN AKTKPREEQY NSTYRVVSVL TVLHQDWLNG KEYKCKVSNK ALPAPIEKTI SKAKGQPREP QVYTLPPSRD ELTKNQVSLT CLVKGFYPSD IAVEWESNGQ PENNYKTTPP VLDSDGSFFL YSKLTVDKSR WQQGNVFSCS VMHEALHNHY TQKSLSLSPG KHHHHHH
Q&A
What is the basic structure of mouse IL-21R?
Mouse IL-21R is a type I cytokine receptor comprising 521 amino acids, including a 19 amino acid signal peptide, a 218 amino acid extracellular domain (ECD) containing 4 conserved cysteine residues, a fibronectin type III domain, and a WSXWS motif. The structure also includes a 21 amino acid transmembrane domain and a 271 amino acid cytoplasmic domain with a Box 1 motif, a kinase domain, and several tyrosine phosphorylation sites. One notable phosphorylation site is pY510, which mediates STAT binding for signal transduction .
How does mouse IL-21R compare structurally to IL-21R in other species?
The mouse IL-21R extracellular domain shares varying degrees of amino acid identity with other species: 69% with human, 91% with rat, 65% with equine, 63% with canine, and 58% with bovine IL-21R. This high conservation, particularly between mouse and rat, suggests evolutionary importance of this receptor's function . When designing cross-species studies, researchers should consider these homology differences, as they may affect ligand binding specificity and downstream signaling efficacy.
Which cell types express IL-21R in mice?
IL-21R is predominantly expressed on lymphoid tissues with varying expression levels depending on cell type and activation status. The highest expression is observed on mature, activated, follicular, and germinal center B cells. Other expressing cells include:
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NK cells
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Activated T cells
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Dendritic cells
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Alternatively activated macrophages
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Intestinal lamina propria fibroblasts
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Epithelial cells
Expression patterns change during immune responses and in disease states, with upregulation often observed in allergic skin inflammation, systemic lupus erythematosus, and diffuse large B cell lymphoma .
What are the best methods for detecting IL-21R expression in mouse cells?
Flow cytometry is a reliable method for detecting IL-21R expression on mouse cells. For optimal results:
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Harvest cells while maintaining viability (>95%)
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Block Fc receptors to prevent non-specific binding
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Stain with anti-mouse IL-21R antibodies (e.g., Catalog # AF596)
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Use appropriate fluorochrome-conjugated secondary antibodies (e.g., Phycoerythrin-conjugated Anti-Goat IgG)
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Include isotype controls (e.g., Catalog # AB-108-C) to determine background staining
This approach has been validated in mouse cell lines such as A20 B cell lymphoma . When analyzing primary cells, additional markers should be included to identify specific cell populations of interest.
How can I establish an in vitro system to study IL-21R signaling in mouse cells?
To establish an effective in vitro system:
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Select appropriate mouse cell types based on research questions (B cells, T cells, or NK cells)
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For primary cells, consider magnetic or flow cytometric sorting to obtain pure populations
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Culture cells in complete media supplemented with appropriate survival factors
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Stimulate cells with recombinant mouse IL-21 (effective dose range: 75-500 ng/mL)
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For signaling studies, examine STAT phosphorylation (especially STAT3) at various time points (5-60 minutes)
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For functional studies, assess proliferation, survival, or differentiation over 24-96 hours
Researchers should validate receptor expression before experiments and consider combination treatments with other cytokines (IL-4, IL-2) that share signaling components with IL-21R.
What are the considerations when using recombinant mouse IL-21R proteins in research?
When using recombinant mouse IL-21R proteins:
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Choose the appropriate format: The carrier-free version (without BSA) is recommended for applications where BSA might interfere, while the standard version with BSA offers enhanced stability and longer shelf-life .
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Reconstitution protocol: Reconstitute lyophilized protein at 100 μg/mL in sterile PBS and avoid repeated freeze-thaw cycles to maintain activity .
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Storage considerations: Upon receipt, store immediately at recommended temperature, typically -20°C to -80°C for long-term storage .
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Functional validation: Before use in binding assays or as blocking agents, validate functionality through binding assays with recombinant mouse IL-21.
How does IL-21R interact with the common gamma chain in signaling?
IL-21R forms a heterodimeric receptor complex with the common gamma chain (γc), which is also used by IL-2, IL-4, IL-7, IL-9, IL-13, and IL-15 receptors. This interaction is required for effective signal transduction . Mechanistically:
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IL-21 binding to IL-21R induces conformational changes that enable γc recruitment
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The cytoplasmic domains of both receptors associate with Janus kinases (JAKs)
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JAK1 associates with IL-21R while JAK3 binds to the γc chain
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JAK activation leads to phosphorylation of tyrosine residues on IL-21R
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These phosphorylated residues serve as docking sites for STAT proteins (primarily STAT3, but also STAT1 and STAT5)
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Phosphorylated STATs dimerize and translocate to the nucleus to regulate gene expression
Disruption of this interaction through genetic knockout or pharmacological inhibition impairs all IL-21-mediated cellular responses.
What are the main transcription factors activated downstream of IL-21R in mice?
IL-21R signaling activates several transcription factors that mediate its diverse biological effects:
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STAT3: The primary STAT activated by IL-21R, essential for B cell differentiation, T follicular helper (TFH) cell development, and Th17 differentiation .
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STAT1 and STAT5: Activated to a lesser extent than STAT3, contributing to cell-type specific responses.
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Blimp-1 (PRDM1): In B cells, IL-21R signaling induces Blimp-1 expression, which drives plasma cell differentiation .
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Bcl-6: In T cells, IL-21R signaling can reinforce Bcl-6 expression, which is essential for TFH cell differentiation and maintenance .
The balance between these transcription factors determines cell fate decisions and functional outcomes in response to IL-21.
How does IL-21R signaling contribute to autoimmune pathology in mouse models?
IL-21R signaling contributes to autoimmune pathology through multiple mechanisms:
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In systemic lupus erythematosus (SLE) models:
Studies using IL-21R knockout donor cells in chronic graft-versus-host disease (cGVHD) models demonstrated attenuated lupus-like renal disease compared to wild-type donor cells . This indicates a critical role for IL-21R signaling in both T cell and B cell compartments during autoimmune pathogenesis.
What is the role of IL-21R in intestinal inflammation models?
IL-21R signaling plays a protective role in dextran sodium sulfate (DSS)-induced colitis through:
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Suppression of Th1 responses: IL-21R-deficient mice exhibit heightened Th1 inflammatory responses during DSS-induced colitis .
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Promotion of Th2, Th17, and Treg responses: IL-21R knockout mice demonstrate reduced Th2, Th17, and regulatory T cell responses during intestinal inflammation .
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Regulation of CD8+ T cells: IL-21R deficiency leads to markedly elevated CD8+CD44+IFN-γ+ T cells in the lamina propria of inflamed intestines .
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Macrophage regulation: Spontaneous inflammatory cytokine release by macrophages in the lamina propria is significantly increased in IL-21R knockout mice .
These findings demonstrate that IL-21/IL-21R signaling has tissue-specific and context-dependent roles, being pathogenic in some autoimmune models while protective in certain inflammatory conditions.
What approaches can be used to therapeutically target IL-21R signaling in mouse models?
Several approaches can be employed to modulate IL-21R signaling for therapeutic purposes:
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Recombinant IL-21 administration: In DSS-induced colitis, treatment with recombinant IL-21 after disease onset ameliorated intestinal inflammation in C57BL/6 mice .
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IL-21R-Fc fusion proteins: These chimeric proteins act as decoys by binding free IL-21, preventing receptor activation. The optimal concentration for neutralization depends on the experimental system but typically ranges from 1-10 μg/mL .
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Anti-IL-21R antibodies: These directly block IL-21 binding to its receptor. Validated antibodies like AF596 can be used both in vitro and in vivo to inhibit IL-21 signaling .
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Genetic approaches: IL-21R knockout mice or conditional knockout systems can be used to assess the role of IL-21R in specific cell types or disease stages.
The effectiveness of these approaches varies depending on the disease model and timing of intervention.
How does IL-21R signaling differentially affect distinct B cell subsets in mice?
IL-21R signaling has diverse effects on different B cell subpopulations:
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Germinal center B cells: IL-21R signaling is critical for germinal center formation and maintenance. IL-21R-deficient mice show impaired germinal center responses in chronic graft-versus-host disease models .
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Memory B cells: IL-21R engagement is important for effective memory B cell responses, affecting both generation and maintenance of these cells .
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Plasma cells: IL-21R signaling induces Blimp-1 expression, which drives plasma cell differentiation. In its absence, autoantibody production is significantly reduced .
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Naive B cells: IL-21 acts together with IL-4 to promote efficient B cell IgG1 production, with both cytokines necessary for normal germinal center architecture .
These differential effects highlight the context-dependent nature of IL-21R signaling across B cell development and activation states.
How do IL-21R-deficient mice differ from wild-type mice in humoral immune responses?
IL-21R-deficient mice exhibit several key differences in humoral immunity:
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Antibody production: In chronic graft-versus-host disease models, mice receiving IL-21R-deficient donor cells show significantly lower levels of total IgG antibodies at early time points (weeks 2-7), though these differences diminish by week 18 .
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Autoantibody production: Anti-dsDNA autoantibodies are detected only transiently and at low titers in IL-21R-deficient hosts compared to wild-type hosts .
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Isotype switching: Total IgG1 and anti-dsDNA IgG1 antibodies are substantially reduced or absent in IL-21R-deficient hosts, indicating defective isotype switching to IgG1 .
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Kinetics of response: The antibody response in IL-21R-deficient mice typically peaks earlier and at lower levels than in wild-type mice .
These findings indicate that while IL-21R signaling is not absolutely required for antibody production, it significantly shapes the magnitude, kinetics, and isotype profile of humoral responses.
What is the relationship between IL-21R signaling and T follicular helper cell maintenance?
IL-21R signaling is essential for sustaining T follicular helper (TFH) cell numbers and function:
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In chronic graft-versus-host disease models, donor T cells lacking IL-21R show impaired maintenance of TFH phenotype and function .
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IL-21 produced by TFH cells acts in an autocrine manner to reinforce the TFH program through continued expression of Bcl-6 and other TFH-associated genes.
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This creates a positive feedback loop where initial IL-21 production promotes TFH differentiation, leading to increased IL-21 production and sustained TFH responses .
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The absence of IL-21R signaling does not appear to affect the balance between T regulatory cells and Th17 cells, suggesting a TFH-specific role in these models .
These findings highlight the cell-intrinsic role of IL-21R in maintaining TFH cells, which are critical for providing help to B cells in germinal centers.
What controls should be included when studying IL-21R knockout mice?
When using IL-21R knockout mice, several controls are essential:
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Littermate wild-type controls: To minimize genetic background effects that might confound interpretation.
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Heterozygous controls: To assess potential gene dosage effects, particularly important when studying partial signaling defects.
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Cell-specific knockouts: For comparison with global knockouts to distinguish cell-intrinsic from extrinsic effects.
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Age and sex matching: IL-21R-related phenotypes may vary with age and between sexes.
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Environmental consistency: Housing conditions should be standardized as microbiome differences can influence immune phenotypes.
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Verification of knockout: Confirm absence of IL-21R expression by flow cytometry and/or RT-PCR, as incomplete deletion or compensatory mechanisms may occur.
These controls help ensure that observed phenotypes are specifically due to IL-21R deficiency rather than confounding factors.
How can discrepancies in IL-21R research findings between different mouse strains be addressed?
To address strain-specific differences in IL-21R research:
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Direct comparative studies: When possible, repeat key experiments in multiple strains under identical conditions.
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Backcrossing: Consider backcrossing IL-21R mutations onto different strain backgrounds to isolate strain-specific effects.
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Mixed background controls: In studies using mixed background mice, ensure proper controls of the same mixed background are used.
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Molecular validation: Confirm that downstream signaling pathways from IL-21R are conserved (or identify differences) across strains by measuring STAT phosphorylation and target gene expression.
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Functional validation: Assess whether cellular responses to IL-21 (proliferation, differentiation, cytokine production) differ between strains.
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Genetic modifier identification: For major discrepancies, consider mapping studies to identify genetic modifiers influencing IL-21R signaling.
These approaches can help reconcile seemingly contradictory findings and improve our understanding of context-dependent IL-21R functions.
Product Science Overview
Interleukin-21 receptor (IL-21R) is a type I transmembrane glycoprotein that belongs to the class I cytokine receptor family, specifically the type 4 subfamily . This receptor plays a crucial role in the immune system by mediating the effects of interleukin-21 (IL-21), a cytokine involved in the regulation of immune responses .
The IL-21 receptor is composed of an extracellular domain, a transmembrane domain, and an intracellular domain . The extracellular domain is responsible for binding IL-21, while the intracellular domain is involved in signal transduction . The receptor forms a complex with the common gamma chain (γc), which is also a component of receptors for other cytokines such as IL-2, IL-4, IL-7, IL-9, IL-13, and IL-15 .
IL-21R is highly expressed on various immune cells, including CD4+ and CD8+ T cells, B cells, and natural killer (NK) cells . The interaction between IL-21 and IL-21R plays a pivotal role in the survival, proliferation, and differentiation of these cells . For instance, IL-21 enhances the secretion of interferon-gamma (IFN-γ) in NK cells and promotes the differentiation of B cells into immunoglobulin-producing cells .
Recombinant mouse IL-21R is produced using advanced biotechnological methods to ensure high purity and biological activity . The recombinant protein is typically expressed in a mouse myeloma cell line and purified to achieve a purity level of over 95% . This recombinant form is used in various research applications, including studying the signaling pathways mediated by IL-21 and investigating the therapeutic potential of targeting IL-21R in immune-related diseases .
Recombinant mouse IL-21R is widely used in immunological research to understand the mechanisms underlying immune responses and to develop potential therapeutic strategies . It is particularly valuable in studies involving the modulation of immune cell functions, the development of vaccines, and the treatment of autoimmune diseases and cancers .
