Anti-Mouse CD279 (PD-1) [Clone RMP1-14] — Purified in vivo GOLD™ Functional Grade

Clone RMP1-14 is most commonly used in vivo in mice for studies involving blocking PD-1 signaling, especially in the context of cancer immunotherapy, preclinical anti-tumor efficacy, and immune regulation.

Key in vivo applications include:

• Cancer immunotherapy studies: RMP1-14 is a standard tool for evaluating PD-1 blockade as a therapeutic strategy, frequently used in syngeneic and genetically engineered mouse tumor models (e.g., MC38 colon carcinoma, B16 melanoma). It is employed to test the effect of PD-1 inhibition on immune cell-mediated tumor clearance, tumor growth reduction, and survival outcomes.

• Mechanistic studies of immune regulation: The antibody is applied to dissect mechanisms of T cell exhaustion, tolerance, and overall immunoregulation, since PD-1 plays a key role in dampening T cell activity during chronic infection and tumor progression.

• Combination immunotherapy research: RMP1-14 is frequently used in tandem with other immune-modulating agents (such as anti-CTLA-4 antibodies or chemotherapy) to study synergistic effects and design combination strategies for cancer treatment.

• In vivo functional assays: Beyond blocking studies, researchers use RMP1-14 to probe T cell responses and cytokine production by disrupting PD-1:PD-L1/PD-L2 engagement, often assessing outcomes such as T cell proliferation and cytokine release.

Practical features:

• Dosing protocols: Standard regimens are 200–500 μg per mouse every 3–4 days, delivered intraperitoneally; specific dose may be adjusted for tumor type and experimental needs.
• Buffer/diluents: Commonly formulated in phosphate-buffered saline (PBS) or normal saline for in vivo injection, ensuring antibody stability and animal safety.
• Isotype/effector function: RMP1-14 is usually a rat IgG2a, which can engage mouse Fc receptors and trigger additional effector functions such as antibody-dependent cellular cytotoxicity (ADCC).
• Specificity: It binds mouse PD-1 with high affinity and is not cross-reactive with human PD-1, making it suitable for mouse models but not humanized scenarios.

RMP1-14 is a benchmark antibody for mouse PD-1 blockade studies, valued for its well-established protocols, extensive publication record, and reliability.

Commonly used antibodies or proteins employed in combination with RMP1-14 (murine anti-PD-1) in the literature include other anti-PD-1 clones (such as 1A12 and J43), PD-L1/PD-L2 Fc fusion proteins (to assay blocking activity), and immune checkpoint reagents like anti-PD-L1, anti-CTLA-4, and various markers or modulators for T cell studies.

Key antibodies and proteins frequently used with RMP1-14:

• Other anti-PD-1 clones:

  • 29F.1A12: Often directly compared with or used alongside RMP1-14 in mechanistic, blocking, and functional studies due to its higher avidity and blocking capacity.
  • J43: Another common anti-PD-1 clone assessed for functional overlap or synergy with RMP1-14.
  • RMP1-30: Sometimes used in parallel for epitope mapping or staining experiments.

• PD-L1 and PD-L2 fusion proteins:
  Used to directly test the blocking capacity of RMP1-14 against PD-1 ligand interactions.

• Anti-PD-L1 monoclonal antibodies:
  Such as 10F.9G2 and MIH6, often used in combination or comparison with RMP1-14 to dissect PD-1/PD-L1 pathway mechanisms.

• Anti-CTLA-4 monoclonal antibodies:
  Frequently combined with RMP1-14 for studying synergistic effects in tumor immunotherapy models.

• Other combinations and reagents:

  • SEMA4D antibodies: Used in some studies for combination therapy approaches.
  • Surface markers like CD8, CD4, or other T cell/immune markers for phenotyping and functional assays.

• Humanized checkpoint inhibitors for comparison:
  Nivolumab and pembrolizumab (human anti-PD-1s) are sometimes referenced or modeled against RMP1-14 in murine studies to parallel clinical strategies.

Summary table:

The most common combinations in the literature are RMP1-14 with 29F.1A12 and J43 for PD-1 functional studies, and RMP1-14 with anti-PD-L1 or anti-CTLA-4 for combination immunotherapeutic models. Using multiple anti-PD-1 clones can help clarify blocking versus agonistic properties, while combining RMP1-14 with checkpoint pathway antibodies (PD-L1, CTLA-4) enables detailed immune interaction studies relevant to cancer immunotherapy.

Clone RMP1-14 is a rat IgG2a monoclonal antibody widely used in preclinical research to block the mouse PD-1 immune checkpoint, primarily for in vivo studies of cancer immunotherapy and T cell biology. The key scientific findings from citations involving RMP1-14 are:

• Proven Efficacy in Preclinical Tumor Models: RMP1-14 reliably enhances anti-tumor immune responses, reduces tumor growth, and improves survival in various mouse cancer models, establishing it as an effective tool for investigating PD-1 blockade.

• Mechanism of Action: RMP1-14 specifically binds to the extracellular domain of mouse PD-1, blocking interactions with its ligands PD-L1 and PD-L2, thereby preventing inhibitory signaling and promoting T cell activation.

• Functional Role as a Blocker: While some anti-PD-1 clones (e.g., RMP1-30) display agonist activity and immunosuppressive effects in certain contexts, RMP1-14 predominantly acts as a blocking antibody and is not associated with significant agonist or depletion activity.

• Binding Affinity and Comparative Efficacy: Comparative studies show RMP1-14 has strong binding affinity and blocking function among mouse-specific anti-PD-1 clones, although clones like 1A12 exhibit higher avidity and greater potency at lower concentrations. Against J43, RMP1-14 showed more potent tumor inhibition and survival benefits, attributed to its higher binding affinity.

• Well-Characterized Dosing Protocols and Consistency: RMP1-14’s dosing and administration schemes have been extensively validated, reducing study variability and troubleshooting requirements for new experiments.

• Development and Origin: RMP1-14 was generated via hybridoma technology from rats immunized with mouse PD-1 protein, with selection for high specificity, high affinity, and potent blockade.

• Species-Specificity: It is highly effective for mouse studies but lacks binding to human PD-1, highlighting the importance of species cross-reactivity in translational research.

• Availability and Benchmarking: RMP1-14's broad commercial availability and extensive citation base make it a standard for benchmarking in immuno-oncology research, facilitating reproducibility and robust conclusions.

• Structural and Sequence Insights: Sequencing of RMP1-14's heavy and light chain has defined its molecular signature and identified complementarity-determining regions key to binding.

• Role in Tumor Microenvironment Studies: RMP1-14 has helped establish scientific bases for clinical strategies targeting the tumor immune microenvironment to enhance immunotherapies.

In summary, RMP1-14 is an established, well-characterized blocking antibody for mouse PD-1, utilized extensively to model and understand immune checkpoint blockade, optimize dosing, and develop preclinical cancer therapies. It provides consistent, species-specific results with validated protocols, serving as a benchmark and reliable reagent for immuno-oncology studies.

Dosing regimens for clone RMP1-14 in mouse models vary based on study objectives, tumor models, mouse strains, immune competency, and administration route, but typical protocols use 200–500 µg per mouse intraperitoneally every 3–4 days. Adjustments are made depending on the specific mouse model, tumor biology, and desired pharmacodynamic effects.

Key variations across different mouse models:

• Tumor type and strain: Dosing and efficacy may vary with tumor type (e.g., MC38 colon carcinoma, B16 melanoma), mouse strain, and immune system status. Some strains or models may require dose or frequency adjustments for optimal results.

• Route of administration: Intraperitoneal (IP) injection is standard, but intravenous (IV) administration is also used and has shown comparable efficacy in certain syngeneic models (e.g., MC38).

• Published examples:

  • Syngeneic tumor models (MC38, B16): Frequently use 200 µg per dose IP every 3–4 days.
  • Custom schedules: Some experiments use 3 injections spaced 3 days apart (e.g., days 0, 3, 7).
  • Lower doses: Certain studies use doses as low as 100 µg per injection, particularly in immunophenotyping or when combined with other therapies.

• Buffer/diluents: Antibody is commonly diluted in phosphate-buffered saline (PBS) or normal saline for injection.

• Mouse model/tumor-specific considerations: Variable tumor growth rates or immune responses (due to strain or tumor selection) may dictate modifications in dose and interval. Strain-specific immune differences can influence both pharmacodynamics and safety of RMP1-14.

• Humanized models: Efficacy can differ when using humanized mouse models versus standard inbred strains, particularly if cross-reactivity with human PD-1 is relevant.

Summary Table: Typical RMP1-14 Dosing Regimens in Mice

Important additional notes:

• Dosing may need optimization in each new tumor type, strain, or combination therapy setting.
• Responses can differ due to mouse strain-specific immunity and tumor microenvironment.
• Clones may not cross-react with non-mouse PD-1; using RMP1-14 in non-murine or humanized models requires careful validation.

In sum, the 200–500 µg IP every 3–4 days regimen is the most widely used but requires adjustment for specific models or study objectives. Always consult primary data and pilot studies for your particular model.