Recombinant Mouse Interleukin-4 (Il4) (Active)
Description
Biological Functions
IL-4 is a pleiotropic cytokine secreted by mast cells, T cells, eosinophils, and basophils. Key roles include:
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Immune Regulation: Drives differentiation of naïve T cells into Th2 cells, promoting IgE and IgG1 class switching in B cells .
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Inflammation Modulation: Upregulates MHC class II and CD23 expression on B cells and monocytes .
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Neuroimmunology: Enhances memory and learning via STAT6 signaling in the brain .
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Autophagy Induction: Stimulates dendritic cell autophagy by inhibiting mTORC1 and inducing RUFY4 .
Expression Systems
Functional Assays
Key Research Findings
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TH2 Response Dependency: IL-4Rα knockout mice show 1,000-fold reduced IgE and abolished Th2 responses during N. brasiliensis infection .
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Cross-Species Activity: Human IL-4 splice isoforms (e.g., IL-4δ2) remain functional in mice, inducing lymphocyte infiltration via STAT6 .
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Autophagy in Dendritic Cells: IL-4 enhances antigen presentation by promoting autophagosome formation .
Critical Considerations for Experimental Use
Product Specs
Target Background
- Downregulation of macrophage insulin receptor substrate 2 (Irs2) by hyperinsulinemia impairs IL-4-induced M2a-subtype macrophage activation in obesity. PMID: 30451856
- Nuclear factor of activated T cells (NFAT) interacting protein 1 (Ndfip1) preserves regulatory T cell (Treg) lineage stability and immune homeostasis by preventing the expansion of highly proliferative and metabolically active Treg cells and by preventing pathological secretion of IL-4 from Treg cells. PMID: 28580955
- IL-4/STAT6 signaling needs to be finely tuned to ensure proper development and function of homing Th2 cells. PMID: 29738764
- By establishing that IL-4 is posttranslationally regulated by thioredoxin (TRX)-promoted reduction of a disulfide bond, our findings highlight a novel regulatory mechanism of the type 2 immune response that is specific to IL-4 over interleukin-13 (IL-13). PMID: 30104382
- The vascular endothelial growth factor receptor 1 (VEGFR1)-mediated signaling suppressed IL-4-induced arginase 1 (Arg-1) expression. PMID: 29110610
- The results obtained in the present study suggest that a signaling pathway mediated by Fc receptor gamma (FcRg) or the FcRg-Syk axis is commonly required for innate basophil IL-4 responses under conditions mimicking encounters with allergen sources. PMID: 26703455
- IL-4Delta2 did not compete with IL-4 for IL-4Ralpha binding and did not interfere with the downstream STAT-6 phosphorylation in T cells. PMID: 28917204
- This study demonstrates that IL4 and IL21 cooperate to induce the high Bcl6 protein level required for germinal center formation. PMID: 28875978
- The complex role of IL-4 in autoimmunity and cholangitis. PMID: 27721424
- The results demonstrate that IL-4 can restore insulin sensitivity in adipocytes via mechanisms not associated with induced adipogenesis or de novo formation of lipid depots. PMID: 29738684
- Interleukin 4 (IL-4) signaling prevents Chlamydia trachomatis infection from inducing upper genital tract (UGT) pathology. PMID: 28765368
- In the lung, surfactant protein A (SP-A) enhanced IL-4-dependent macrophage proliferation and activation, accelerating parasite clearance and reducing pulmonary injury after infection with a lung-migrating helminth. In the peritoneal cavity and liver, C1q enhancement of type 2 macrophage activation was required for liver repair after bacterial infection. PMID: 28495878
- Data, including data from studies using transgenic mice, suggest that over-expression of IL4 in thyroid tissue/cells up-regulates expression of dual oxidase 1 (Duox1), dual oxidase maturation factor 1 (Duoxa1), and pendrin (Slc26a4) in thyroid tissue/cells; expression of sodium-iodide symporter (Slc5a5) is down-regulated. PMID: 27599561
- We defined a molecular mechanism for IL-4 downregulation of involucrin in keratinocytes, which may play an important role in the pathogenesis of atopic dermatitis (AD). PMID: 26918372
- In this study, the effect of continuous IL-4 delivery or bioactive implant coating that constitutively releases a protein inhibitor of CCL2 signaling (7ND) on particle-induced osteolysis were studied in the murine continuous femoral intramedullary particle infusion model. PMID: 27114284
- T follicular helper (Tfh) cells arise in tumor-draining lymph nodes where they produce an abundance of IL4. Deletion of IL4-expressing Tfh cells improves antitumor immunity, delays tumor growth, and reduces the generation of immunosuppressive myeloid cells in the lymph nodes. PMID: 27920023
- Findings suggest that interleukin 4 (IL-4) affects anti-tumor immunity and constitutes an attractive therapeutic target to reduce immune suppression in the tumor microenvironment. PMID: 28733709
- This study demonstrates that environmental IL-4 plays a role in conditioning early thymic progenitor lineage choice, which would impact T cell development. PMID: 28893952
- This study demonstrates that eosinophils subvert host resistance to an intracellular pathogen by instigating non-protective IL-4 in CCR2(-/-) mice. PMID: 27049063
- Findings show that during intestinal helminth infection, IL-4 derived from T follicular helper cells is required for IgE class switching and plasmablast formation. PMID: 28533444
- Data suggest that Il4 (usually released from helper T-cells) induces cyclooxygenase 1 (Cox1) in macrophages at the post-transcriptional level; activation of AMP-activated protein kinase (Ampk) by metformin blocks Il4-dependent induction of Cox1 and blocks macrophage polarization/activation. PMID: 28684424
- IL-4 is required for the development of ex-Foxp3 T helper 2 cells. PMID: 28507062
- We conclude that a state of haploinsufficiency for the Il4 gene locus is specifically relevant for IL-4-dependent IgE responses to allergens, with the amount of IL-4 produced in the hemizygous condition falling close to the threshold required for switching to IgE production. PMID: 28115531
- Priming of T helper cells by IL-6-deficient antigen-presenting dendritic cells preferentially leads to accumulation of a subset of follicular helper T cells characterized by high expression of GATA3 and IL-4. PMID: 27474166
- Eosinophils drive progression of myocarditis to inflammatory dilated cardiomyopathy (DCMi), cause severe DCMi when present in large numbers, and mediate this process through IL-4. PMID: 28302646
- These data suggest that although IL-4-stimulated alternatively activated macrophages upregulate fatty acid oxidation, fatty acid oxidation is dispensable for macrophage polarization and high-fat diet-induced metabolic dysfunction. Macrophage fatty acid oxidation likely plays a correlative, rather than causative, role in systemic metabolic dysfunction. PMID: 28223293
- Excessive IL-4 levels in the mesenteric lymph nodes (MLNs) directly inhibited the induction of antigen-induced regulatory T cells (aiTregs) and caused enteropathy. The aiTregs generated in the attenuation of T cell-dependent food allergic enteropathy may function differently than aiTregs induced in a tolerance model. PMID: 28234975
- This study demonstrates that wild-type mice develop an eosinophilic Th2 airway disease in response to Alternaria alternata exposure, whereas IL-4-deficient mice exhibit a primarily neutrophilic response. PMID: 27815425
- Study showed that the intraperitoneal administration of the exogenous cytokines interferon-gamma (IFN-gamma) (to promote M1 microglia) and IL-4 (to promote M2 microglia) can correctly modulate the timing of the M1 to M2 ratio to affect epileptogenesis and to improve cognitive function in pilocarpine-induced status epilepticus. PMID: 27956120
- These findings indicate that IL-4, a canonical Th2 cell cytokine, can sometimes promote rather than impair Th1 cell-type immune responses. PMID: 27298446
- Keratinocyte gene expression is critically shaped by IL-4, altering cell fate decisions, which are likely important for the clinical manifestations and pathology of allergic skin disease. PMID: 27554818
- Data show that lactic acid in tumor microenvironments inhibited interferon-gamma (IFNgamma) and interleukin-4 (IL4) productions from natural killer T (NKT) cells by inhibiting mammalian target of rapamycin (mTOR) signaling. PMID: 27995420
- This study demonstrates that IL-4-mediated control of the precursor population affects the development of virus-specific CD8+ T-cell memory. PMID: 27457412
- IL-4 secretion by group 2 innate lymphoid cells contributes to the allergic response in food allergy by reducing allergen-specific Treg cell and activating mast cell counts. PMID: 27177780
- These studies clearly show a crucial role for IL-4 in the induction of airway hyperresponsiveness following Strongyloides venezuelensis infection and for IL-33/ST2 in maintaining airway hyperresponsiveness and lung Th2 responses. PMID: 27102638
- We used recombinant herpes simplex virus vector S4IL4 that encodes the mouse il4 gene to evaluate the therapeutic potential of IL-4 in naloxone-precipitation morphine withdrawal (MW). One week after microinjection of the vector S4IL4 into the periaqueductal gray (PAG), LacZ or mouse IL-4 immunoreactivity in the ventrolateral PAG was visualized. Enzyme-linked immunosorbent assay (ELISA) showed that vector S4IL4 into the PAG induced the expression of IL-4. PMID: 28206989
- This study demonstrates that IL-4 is increased in the brain of T cell receptor transgenic mice, which exhibit impaired memory and adult hippocampal neurogenesis. PMID: 27432189
- This study shows that il-4 plays an important role in early secreted antigenic target-6 (ESAT-6)-induced monocyte chemoattractant protein-1 (MCP-1) production by macrophages, and suggests a pathway with significance in tuberculosis pathogenesis. PMID: 27154637
- Results indicate that sialic acid-binding immunoglobulin-like lectin 9 (Siglec-9) affects several different signaling pathways in IL-4-stimulated macrophages, which resulted in enhanced induction of Arg1 in Siglec-9-expressing RAW264 cells. PMID: 26540411
- Oct-1 and Oct-2 bound within the Il4 promoter region and the Th2 locus control region (LCR). PMID: 26840450
- Loss of IL-4 promoted expression of M1 microglia/macrophage markers and impaired expression of M2 markers after transient or permanent middle cerebral artery occlusion. PMID: 26732561
- These results indicate a positive role of Batf in promoting the generation of pro-allergic IL-4-producing T-follicular helper cells. PMID: 26278622
- IL-4 induces miR-142-5p and downregulates miR-130a-3p in macrophages, regulating macrophage profibrogenic gene expression in chronic inflammation. PMID: 26436920
- These findings underscore the important collaboration between IL-4 and IL-21 in shaping T-dependent B cell antibody responses. PMID: 26491200
- IL-4 knockout mice display state, but not trait, anxiety, suggesting that reductions in endogenous anti-inflammatory bioactives can engender subtypes of anxiety. PMID: 25772794
- Physiologic doses of interleukin-4 (IL-4) and interleukin-13 (IL-13) have profound anti-lymphangiogenic effects and potently impair lymphatic endothelial cell (LEC) survival, proliferation, and migration. PMID: 26039103
- Concerted activity of IgG1 antibodies and IL-4/IL-25-dependent effector cells trap helminth larvae in the tissues following vaccination with defined secreted antigens, providing sterile immunity to challenge infection. PMID: 25816012
- May be an important factor in providing 1,25D3-induced protection from experimental autoimmune encephalomyelitis. PMID: 25574039
- IL-4-producing DCs are induced under some Th2-provoking situations, and they should play important roles in the initiation of Th2 response. PMID: 26363056
- RUN and FYVE domain-containing protein 4 enhances autophagy and lysosome tethering in response to Interleukin-4. PMID: 26416964
Q&A
What is recombinant mouse IL-4 and what are its key biological functions?
Recombinant mouse IL-4 is a 14-15 kDa pleiotropic immune cytokine typically produced in expression systems such as E. coli cells. It functions as a critical regulator of numerous immune processes including humoral and adaptive immunity. In natural settings, IL-4 is secreted primarily by activated TH2 cells and exhibits multiple biological roles: regulation of immune responses, inhibition of bone resorption, stimulation of activated B-cell and T-cell proliferation, and initiation of allergic responses .
Importantly, IL-4 establishes a positive feedback mechanism by stimulating differentiation of naive helper T cells (Th0) to Th2 cells, which subsequently secrete additional IL-4, amplifying the Th2 response. This feedback loop represents a critical regulatory mechanism in immune homeostasis . Beyond these classical immune functions, research has revealed that IL-4 plays unexpected roles in higher brain functions, particularly in memory and learning processes, indicating its importance extends beyond traditional immunological frameworks .
How does recombinant mouse IL-4 differ from natural IL-4 in experimental applications?
While recombinant mouse IL-4 faithfully reproduces many functions of natural IL-4, researchers should be aware of several key differences that may impact experimental outcomes. Standard recombinant preparations typically maintain high bioactivity but exhibit less stability than natural IL-4 from primary cells. Recombinant versions often lack post-translational modifications present in naturally occurring IL-4, which can affect protein half-life and receptor binding kinetics in certain experimental systems.
This stability issue has driven development of engineered variants such as the Neo-4 cytokine mimetics, which demonstrate hyperstability compared to natural IL-4 while maintaining functional activity. Unlike natural IL-4, these engineered mimetics signal exclusively through the type I IL-4 receptor complex rather than both type I and type II receptors, providing researchers a tool to dissect receptor-specific effects . This distinct signaling profile creates opportunities for investigating differential IL-4 signaling pathways but requires careful consideration when extrapolating results to natural IL-4 function.
What quality control parameters should researchers verify when working with recombinant mouse IL-4?
Critical quality control parameters for recombinant mouse IL-4 include:
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Purity assessment: Verify >97% purity via SDS-PAGE with silver staining to ensure experimental outcomes aren't influenced by contaminants .
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Endotoxin levels: Confirm levels below 0.1 EU/μg as determined by LAL method, as endotoxin contamination can significantly confound immunological experiments .
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Biological activity: Test functionality through appropriate bioassays such as TH2 cell proliferation or STAT6 phosphorylation in responsive cell lines.
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Protein integrity: Confirm proper molecular mass (approximately 14 kDa for mouse IL-4) and N-terminal sequence analysis to verify correct protein translation .
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Formulation verification: Ensure proper reconstitution in appropriate buffer systems (typically modified PBS at pH 7.2-7.4) without additives that might interfere with experimental systems .
Researchers should document these parameters before experiments, as variations between lots or suppliers can significantly impact experimental reproducibility.
What are the optimal concentrations of recombinant mouse IL-4 for different experimental applications?
Optimal concentrations of recombinant mouse IL-4 vary significantly based on experimental context:
It's critical to note that dose-response relationships should be established for each experimental system. For example, in mycobacterial infection models, higher concentrations of IL-4 (100 ng/mL) showed significantly greater reduction in mycobacterial containment compared to lower concentrations (5 ng/mL), demonstrating a concentration-dependent effect that must be carefully controlled .
How should recombinant mouse IL-4 be reconstituted and stored for optimal stability?
For optimal stability and activity retention:
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Reconstitution protocol: Reconstitute lyophilized recombinant mouse IL-4 using sterile, filtered (0.2 μm) buffer. Typical reconstitution buffers include modified Dulbecco's PBS (pH 7.2-7.4) without calcium, magnesium, or preservatives .
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Short-term storage: Once reconstituted, store at 2-8°C for up to one month if maintained in sterile conditions .
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Long-term storage: For extended storage, maintain lyophilized protein desiccated at -20°C to -70°C, where it typically remains stable for 6-12 months .
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Working aliquots: To prevent activity loss from repeated freeze-thaw cycles, prepare single-use aliquots immediately after reconstitution. For dilute solutions, consider adding carrier protein (0.1-1% BSA) to prevent adsorption to container surfaces.
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Freeze-thaw considerations: Strictly avoid repeated freeze-thaw cycles as they significantly reduce bioactivity. Each cycle can result in 10-30% activity loss depending on protein concentration and buffer composition .
What methods can verify functional activity of recombinant mouse IL-4 in experimental systems?
Verifying functional activity is crucial before experimental use. Recommended approaches include:
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STAT6 phosphorylation assay: Measure phosphorylation of STAT6 in responsive cells (e.g., THP-1) using phospho-specific antibodies by Western blot or flow cytometry to confirm IL-4 receptor engagement and downstream signaling.
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Gene expression analysis: Quantify upregulation of IL-4-responsive genes in target cells, including markers like MRC1 (CD206), CCL22, TGF-β1, and CCL18 via qPCR, which are reliably induced in macrophages polarized toward an M2a phenotype .
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Functional cell polarization: Verify macrophage polarization by evaluating morphological changes, surface marker expression (flow cytometry), and functional assays (phagocytosis, cytokine secretion) .
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Bioactivity measurement: For advanced validation, assess biological effects in appropriate model systems, such as measuring impact on mycobacterial containment in infected macrophages, where functional IL-4 demonstrates dose-dependent effects .
When defining experimental protocols, researchers should always include appropriate positive controls (commercially validated IL-4) and negative controls (heat-inactivated IL-4) to ensure system validity.
How can recombinant mouse IL-4 be utilized to study neuroimmune interactions?
Recombinant mouse IL-4 provides valuable research opportunities for investigating neuroimmune interactions:
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Memory and learning models: IL-4 plays a critical role in higher brain functions including memory and learning. Experimental designs can utilize IL-4 administration or IL-4 knockout models to investigate cognitive performance in spatial learning tasks and memory formation .
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T cell-brain communication: Evidence indicates that T cells in cerebrospinal fluid are ideally positioned to communicate with brain cells. Researchers can use IL-4 to manipulate this communication pathway by administering recombinant IL-4 to cerebrospinal fluid or using IL-4 blockers to study resulting cognitive effects .
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Blood-brain barrier investigations: Though the brain has traditionally been viewed as isolated from immune influences by the blood-brain barrier, research now shows crucial neuroimmune interactions for normal brain function. IL-4 can be used to study these interactions in models where immune suppression leads to cognitive impairment .
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Meningeal immune cell studies: Administration of recombinant IL-4 or IL-4 signaling blockers can help investigate how T cells in the subarachnoid space (containing approximately 150,000 leukocytes in humans, 10,000 in mice) contribute to normal cognitive function through cytokine signaling pathways .
This research area represents a paradigm shift in understanding how the immune system, particularly IL-4-producing cells, contributes to normal brain function beyond traditional immunological roles.
What methodologies exist for controlling IL-4 release kinetics in experimental models?
Advanced biomaterial approaches for controlled IL-4 delivery include:
These controlled-release systems offer significant advantages for investigating long-term IL-4 effects in experimental models and hold promise for therapeutic applications.
How is IL-4 signaling being targeted for infectious disease research?
IL-4 signaling research shows particular promise in infectious disease contexts:
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Tuberculosis research: Studies demonstrate that TB patients exhibit higher IL-4 mRNA expression and IL-4/IFN-γ ratios in blood compared to latently infected individuals. This indicates IL-4's potential role in disease progression and susceptibility .
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Mycobacterial containment studies: Human recombinant IL-4 reduces mycobacterial containment in infected macrophages in a dose-dependent manner (5-100 ng/mL). Higher concentrations (100 ng/mL) produce significantly stronger effects than lower doses (5 ng/mL) .
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Immune pathway investigations: IL-4 appears to subvert mycobacterial containment through specific mechanisms:
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Therapeutic targeting approaches: Blocking IL-4 significantly neutralizes its effects on mycobacterial containment, CD4+IFNγ+ levels, and Treg expression, suggesting potential for host-directed therapies .
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Compartment-specific effects: Importantly, IL-4 expression patterns differ between blood and bronchoalveolar lavage (BAL) compartments, with higher expression in blood of TB patients versus latently infected individuals, but no differences in BAL samples. This highlights the importance of studying tissue-specific IL-4 effects .
These findings have significant implications for designing TB vaccines and host-directed therapies targeting IL-4 signaling pathways.
How do engineered IL-4 mimetics compare to natural recombinant IL-4 in research applications?
Engineered IL-4 mimetics represent a significant advancement in cytokine research:
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Structural design approach: Neo-4 IL-4 mimetics are designed based on a de novo engineered IL-2 mimetic scaffold. These proteins are created by introducing substitutions from IL-4 into the Neo-2 scaffold at the IL-4Rα interface, with enhanced receptor binding through affinity maturation .
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Functional comparisons: These engineered mimetics largely recapitulate the signaling and downstream biological functions of natural IL-4 without exhibiting IL-2 bioactivity. This selectivity makes them valuable research tools for isolating IL-4-specific effects .
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Receptor selectivity: Unlike natural IL-4, engineered mimetics signal exclusively through the type I receptor complex. This selectivity provides unprecedented opportunities to investigate the differential functions of type I versus type II IL-4 receptor signaling pathways .
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Stability advantages: A major advantage of engineered mimetics is their hyperstability compared to natural IL-4, which tends to denature under thermal stress. This stability enables direct incorporation into sophisticated biomaterials requiring heat processing, such as 3D-printed scaffolds .
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Applications in complex systems: The thermal stability of engineered IL-4 mimetics (both human and mouse versions) allows their use in applications where natural IL-4 would rapidly degrade, including incorporation into heat-processed biomaterials and sustained delivery systems .
These engineered IL-4 mimetics provide researchers with new tools to study IL-4 biology while overcoming the limitations of stability and receptor selectivity inherent to natural IL-4.
What considerations should researchers make when selecting between different IL-4 formulations for specific experimental goals?
Selection criteria for IL-4 formulations should align with specific research objectives:
| Research Objective | Recommended Formulation | Key Considerations |
|---|---|---|
| Studying canonical IL-4 signaling | Natural recombinant IL-4 | Maintains physiological signaling through both receptor types |
| Long-term in vitro studies | Stabilized IL-4 (with HSA/BSA) | Prevents activity loss during extended experiments |
| Type I receptor-specific effects | Engineered IL-4 mimetics | Provides selective signaling through type I receptors only |
| Biomaterial incorporation | Hyperstable IL-4 mimetics | Withstands processing conditions that would denature natural IL-4 |
| Controlled release studies | IL-4/HSA microparticles | Enables sustained release following first-order kinetics |
| Mycobacterial infection models | Concentration-adjusted natural IL-4 | Allows dose-dependent modulation of antimicrobial responses |
For complex experimental designs, researchers should consider conducting pilot studies comparing different IL-4 formulations to determine which best suits their specific experimental endpoints and measurement techniques.
What are the most promising future directions for IL-4 research in therapeutic applications?
Several promising research directions for IL-4 in therapeutic applications include:
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Macrophage cell therapies: IL-4-releasing microparticles show potential for directing and sustaining pro-regenerative macrophage phenotypes in inflammatory disease treatments. These controlled release systems could enable longer-term therapeutic effects than direct cytokine administration .
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Host-directed therapies for infectious diseases: Research on IL-4's role in mycobacterial containment suggests potential for blocking IL-4 signaling as a host-directed therapy for tuberculosis and possibly other infections where Th1/Th2 balance is critical .
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Neuroimmunological applications: Given IL-4's role in memory and learning, therapeutic approaches targeting IL-4 signaling in neurological disorders represent an emerging area with significant potential .
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Cancer immunotherapy: The finding that increased IL-4 production and IL-4R overexpression occur in many cancers, with IL-4 enhancing tumor progression through increased apoptosis resistance, suggests IL-4 pathway inhibition as a potential cancer treatment strategy .
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Biomaterial integration: Hyperstable IL-4 mimetics that can be directly incorporated into sophisticated biomaterials like 3D-printed scaffolds offer new possibilities for tissue engineering and regenerative medicine applications requiring controlled immunomodulation .
These directions highlight the diverse potential applications of IL-4 research beyond traditional immunology, spanning infectious disease, neuroscience, oncology, and regenerative medicine.
