IP 10 Rhesus macaque
Description
IP-10: Structure and Function
IP-10 belongs to the CXC chemokine family and binds to the CXCR3 receptor. In rhesus macaques:
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Source: Produced by monocytes, T cells, endothelial cells, and stromal cells in response to IFN-γ .
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Primary Functions:
Recombinant IP-10 (His-tagged) for research use is available, with a molecular weight of 8.5 kDa and >95% purity .
Measurement Methods
IP-10 levels in rhesus macaques are quantified using:
| Method | Sensitivity | Assay Type | Applications |
|---|---|---|---|
| ELISA Kit | 20 pg/mL | Colorimetric | Plasma, serum, or tissue samples |
| LEGENDplex™ Panel | Not specified | Multiplex | Inflammatory cytokine profiling |
Key Considerations:
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Sample Stability: Plasma samples should be frozen at -20°C to avoid degradation .
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Cross-Species Reactivity: Ensure kits are validated for rhesus macaque IP-10 (e.g., Sigma-Aldrich’s Rab1104 kit) .
Disease-Associated Roles
IP-10 is a biomarker in multiple infectious models:
Tuberculosis (TB)
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IFN-γ Correlation: IP-10 levels strongly correlate with IFN-γ in TB-infected macaques, particularly after PPD stimulation .
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Diagnostic Utility: Elevated plasma IP-10 distinguishes TB-infected macaques from healthy controls .
SFTSV Infection
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Viral Load Link: IP-10 levels rise during SFTSV viremia and correlate with body temperature and activated T/B cells .
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Immune Suppression: High IP-10 may suppress T cell/NK cell activity, contributing to disease progression .
SARS-CoV-2
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Pro-Inflammatory Role: IFN-γ signaling (via CXCL10/IP-10) exacerbates lung inflammation, as shown in macaques with pulmonary lesions .
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IL-10 Regulation: IL-10 dampens IP-10-driven T cell expansion but promotes tissue-resident memory T cells post-infection .
Schistosomiasis
While IP-10 is not directly mentioned in schistosome studies, rhesus macaques serve as a model for acquired immunity. Chronic infection induces self-cure mechanisms, potentially involving Th1/Th2 cytokine shifts that may indirectly modulate IP-10 .
COVID-19 Pathogenesis
| Parameter | Control | Anti-IFNγ Treatment | Anti-IL-10 Treatment |
|---|---|---|---|
| Lung Inflammation | Moderate | Reduced | Increased |
| Viral Load | Clearance | No change | No change |
| IP-10 Levels | Elevated | ↓ | ↑ |
Research Implications
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Biomarker Potential: IP-10’s strong correlation with IFN-γ and viral load in TB/SFTSV makes it a candidate for early infection detection .
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Therapeutic Targeting: Neutralizing IFN-γ or modulating IL-10 may reduce IP-10-driven pathology in COVID-19 .
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Species-Specific Insights: Rhesus macaques exhibit milder COVID-19 than baboons, suggesting IP-10’s role varies by primate model .
Product Specs
Chemokine (C-X-C motif) ligand 10 (CXCL10), also called 10 kDa IP-10, is a small cytokine of the CXC chemokine family. Secreted by monocytes, endothelial cells, fibroblasts, and other cell types in response to IFN-γ, CXCL10 plays various roles, including attracting monocytes and T cells, facilitating T cell adhesion to endothelial cells, inhibiting tumor growth and bone marrow colony formation, and suppressing angiogenesis. The gene encoding CXCL10 is found on human chromosome 4 within a cluster of several other CXC chemokines. This chemokine exerts its effects by binding to the CXCR3 receptor on the cell surface. Its three-dimensional structure has been elucidated under three different conditions to a resolution of 1.92A.
(a) Reverse-phase high-performance liquid chromatography (RP-HPLC) analysis.
(b) Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis.
C-X-C motif chemokine 10, 10 kDa, Gamma-IP10, IP-10, Small-inducible cytokine B10, CXCL10, SCYB10.
Q&A
What is IP-10 and what is its biological significance in rhesus macaques?
IP-10 is a chemokine involved in leukocyte migration and activation in rhesus macaques. It plays a significant role in inflammatory responses, particularly during infectious diseases such as tuberculosis. IP-10 is produced in response to IFN-γ stimulation and contributes to the recruitment of activated T cells to sites of inflammation. In rhesus macaques, IP-10 has been identified as a potential biomarker for monitoring ongoing inflammation, particularly in tuberculosis infection . The protein shows cross-reactivity between rhesus macaque and human systems, making it valuable for translational research .
What are the baseline levels of IP-10 in healthy rhesus macaques?
According to research, healthy rhesus macaques (n=30) exhibit baseline plasma IP-10 concentrations of 225.53 ± 59.07 pg/ml . This establishes an important reference range for researchers working with these animals. By comparison, rhesus macaques with naturally acquired tuberculosis show significantly elevated levels of 280.77 ± 61.73 pg/ml . Understanding these baseline values is essential for proper experimental design and data interpretation in immunological studies.
What biological samples can be used to measure IP-10 in rhesus macaques?
IP-10 can be measured in several biological samples from rhesus macaques, including:
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Cell culture supernatants
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Plasma
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Serum
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Whole blood after specific antigen stimulation (e.g., PPD-stimulated whole blood)
Each sample type has specific preparation requirements. For example, when using whole blood assays, the sample must be properly incubated with the stimulating antigen (such as PPD for tuberculosis studies), and then plasma can be harvested for measurement. The linearity of dilution varies slightly between sample types, with cell culture supernatants showing 84-96% expected values at 1:2 and 1:4 dilutions, plasma showing 93-87%, and serum showing 90-98% .
What are the optimal methods for detecting and quantifying IP-10 in rhesus macaque samples?
The solid-phase sandwich Enzyme-Linked Immunosorbent Assay (ELISA) is the standard method for detecting and quantifying rhesus macaque IP-10. Commercial kits specific for rhesus macaque IP-10 are available with the following specifications:
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Minimum detectable dose: 20 pg/mL
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Detection method: Solid-phase sandwich ELISA
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Sample volume requirements: Varies by sample type
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Antibody specificity: Detects both rhesus macaque and human IP-10
When using ELISA to measure IP-10, researchers should be aware of the linearity of dilution across different sample types. The assay has been validated for plasma, serum, and cell culture supernatants with recovery percentages ranging from 76-103% depending on sample type and dilution factor .
How does the dynamic of IP-10 expression change during experimental infection with M. tuberculosis?
During experimental M. tuberculosis infection in rhesus macaques, plasma IP-10 levels show a characteristic transient increase. The dynamic changes of plasma IP-10 are generally consistent with IFN-γ patterns in infected animals. Studies tracking IP-10 expression over time (at 0, 6, 10, 12, 18, and 22 weeks post-infection) demonstrate:
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A clear peak in IP-10 levels during the active infection period
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Consistent temporal patterns with IFN-γ expression
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Less pronounced dose-dependent differences compared to IFN-γ (high dose vs. low dose M. tuberculosis)
Interestingly, while IFN-γ peaks were significantly higher in monkeys receiving high doses of M. tuberculosis (500 CFU) compared to those receiving low doses (50 CFU), the differences in IP-10 peaks between these groups were not as significant .
What is the correlation between IP-10 and IFN-γ in rhesus macaques?
A positive correlation exists between IP-10 and IFN-γ in rhesus macaques across different health states. This correlation has been documented in:
| Condition | Spearman's r-value | p-value | Correlation Strength |
|---|---|---|---|
| Healthy controls | 0.4411 | 0.0147 | Moderate positive |
| Natural TB infection | 0.4320 | 0.0171 | Moderate positive |
| PPD-stimulated blood | 0.5648 | 0.0353 | Strong positive |
These correlations suggest a functional relationship between these two immune mediators, with IFN-γ likely driving IP-10 production. The correlation is maintained in both healthy animals and those with tuberculosis, indicating that this relationship is fundamental to immune system function in rhesus macaques .
How do IP-10 and IFN-γ levels compare in tuberculosis-infected versus healthy rhesus macaques?
Comparative analysis of IP-10 and IFN-γ levels in tuberculosis-infected versus healthy rhesus macaques reveals significant differences:
| Biomarker | Healthy Controls (n=30) | TB-Infected (n=30) | Significance |
|---|---|---|---|
| IP-10 | 225.53 ± 59.07 pg/ml | 280.77 ± 61.73 pg/ml | p < 0.05 |
| IFN-γ | 17.73 ± 10.26 pg/ml | 93.57 ± 122.77 pg/ml | p < 0.05 |
How does IP-10 perform as a diagnostic biomarker for tuberculosis in rhesus macaques compared to IFN-γ?
While both IP-10 and IFN-γ increase during tuberculosis infection in rhesus macaques, research indicates that IFN-γ is a more valuable diagnostic biomarker. Key comparative findings include:
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Both IP-10 and IFN-γ levels are significantly elevated in tuberculosis-infected monkeys
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After PPD stimulation, the stimulation index (SI) of IFN-γ is significantly higher than that of IP-10
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The correlation between baseline and PPD-stimulated levels suggests IP-10 may have higher background production
What is the significance of the stimulation index (SI) when evaluating IP-10 versus IFN-γ responses?
The stimulation index (SI), calculated as the ratio of post-stimulation to pre-stimulation levels, is an important metric when comparing IP-10 and IFN-γ as biomarkers. In PPD-stimulation studies of tuberculosis-infected rhesus macaques:
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Both IP-10 and IFN-γ show significant elevation after PPD stimulation
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The SI of IFN-γ is significantly higher than that of IP-10
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The higher SI for IFN-γ indicates greater relative induction compared to baseline levels
This difference in SI suggests that while both markers respond to antigenic stimulation, IFN-γ provides better discrimination between stimulated and unstimulated states, making it more suitable for diagnostic applications in whole blood assays .
What are important controls and variables to consider when designing IP-10 studies in rhesus macaques?
When designing studies investigating IP-10 in rhesus macaques, researchers should consider:
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Control populations: Include age-matched healthy controls to establish baseline values
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Sample collection timing: For infection studies, collect samples at multiple timepoints to capture dynamic changes
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Stimulation protocols: When using antigen stimulation (e.g., PPD), standardize incubation times and antigen concentrations
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Parallel measurement: Always measure IFN-γ alongside IP-10 to establish correlation and comparative dynamics
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Sample processing: Standardize processing times to minimize variability in cytokine measurements
The research demonstrates that experimental infection models show distinct kinetics, with transient increases in both IP-10 and IFN-γ. Sampling at 0, 6, 10, 12, 18, and 22 weeks post-infection has been successful in capturing these dynamics .
How might IP-10 measurements be affected by comorbidities in rhesus macaques?
IP-10 levels may be affected by various comorbid conditions in rhesus macaques. While the search results primarily focus on tuberculosis infection, other inflammatory or infectious conditions may impact IP-10 expression. For example:
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Chronic diarrhea conditions may affect systemic inflammatory markers
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Co-infections (viral, bacterial, parasitic) could independently stimulate IP-10 production
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Inflammatory conditions of the GI tract, such as colitis, could influence systemic cytokine profiles
When designing studies, researchers should screen for common infections such as SIV, SRV, STLV1, and others that might confound IP-10 measurements. Additionally, detailed pathological examination may be necessary to identify conditions that could affect inflammatory marker profiles .
What are the implications of rhesus macaque IP-10 research for human tuberculosis diagnostics?
Research on IP-10 in rhesus macaques has important translational implications for human tuberculosis diagnostics:
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The moderate positive correlation between IP-10 and IFN-γ in rhesus macaques parallels findings in human studies
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The cross-reactivity of IP-10 between rhesus macaques and humans (as noted in ELISA specifications) facilitates comparative studies
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The limitations of IP-10 as a diagnostic biomarker in rhesus macaques inform human diagnostic development
While most human studies suggest the diagnostic accuracy of IP-10 is on par with IFN-γ release assays (IGRAs), the rhesus macaque model suggests some limitations. These differences highlight the importance of species-specific validation when developing diagnostic approaches .
How do findings about IP-10 in rhesus macaques compare to those in other animal models of tuberculosis?
Findings about IP-10 in rhesus macaques differ somewhat from those in other animal models of tuberculosis:
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In bovine tuberculosis, contradictory results exist regarding IP-10 as a diagnostic biomarker
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Some studies report no significant difference in IP-10 responses to mycobacterial antigens before and after stimulation in cattle
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Other reports suggest IP-10 might be a valuable diagnostic biomarker of M. bovis infection in cattle
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In M. bovis-infected buffaloes, IP-10 is produced in much greater abundance than IFN-γ after stimulation with RD-1 gene encoded proteins
These differences highlight the species-specific nature of immune responses and the importance of validating biomarkers in each model system being studied. The rhesus macaque model, with its closer relationship to humans, offers particular value for translational research .
Product Science Overview
IP-10, also known as C-X-C motif chemokine 10 (CXCL10), is a small cytokine belonging to the CXC chemokine family. It is also referred to as 10 kDa interferon gamma-induced protein (IP-10). This chemokine is secreted by various cell types, including monocytes, endothelial cells, and fibroblasts, in response to interferon-gamma (IFN-γ) .
CXCL10 plays several critical roles in the immune system:
- Chemoattraction: It attracts monocytes, T cells, and other immune cells to sites of inflammation.
- T Cell Adhesion: Promotes the adhesion of T cells to endothelial cells, facilitating their migration to inflamed tissues.
- Antitumor Activity: Exhibits antitumor properties by inhibiting tumor growth and angiogenesis.
- Inhibition of Bone Marrow Colony Formation: Suppresses the formation of bone marrow colonies, impacting hematopoiesis .
The gene encoding CXCL10 is located on human chromosome 4, within a cluster of other CXC chemokines. The protein itself is a non-glycosylated polypeptide chain consisting of 77 amino acids, with a molecular mass of approximately 8.7 kDa . The three-dimensional crystal structure of CXCL10 has been determined under various conditions, providing insights into its functional mechanisms .
The recombinant form of IP-10 from Rhesus macaque is produced in Escherichia coli (E. coli). This recombinant protein is a single, non-glycosylated polypeptide chain containing 77 amino acids. It is purified using proprietary chromatographic techniques to ensure high purity and biological activity .
- Appearance: Sterile filtered white lyophilized (freeze-dried) powder.
- Formulation: Lyophilized from a 0.2 µm filtered concentrated solution in 1×PBS, pH 7.4.
- Solubility: Recommended to reconstitute in sterile water to a concentration of at least 100 µg/ml, which can then be further diluted.
- Stability: Stable at room temperature for up to 3 weeks when lyophilized. Upon reconstitution, it should be stored at 4°C for short-term use (2-7 days) and below -18°C for long-term storage. Adding a carrier protein like HSA or BSA is recommended to prevent freeze-thaw cycles .
