Anti-Mouse CD152 (CTLA-4) [Clone 9H10] — Purified in vivo GOLD™ Functional Grade

Common In Vivo Applications of Clone 9H10 in Mice

Clone 9H10 is a widely used Syrian hamster IgG monoclonal antibody that specifically targets mouse CTLA-4 (CD152), a key immune checkpoint molecule expressed on activated T and B lymphocytes. Its primary in vivo applications in mice are centered on immunology and cancer research, leveraging its ability to modulate immune responses by blocking CTLA-4's natural function.

Immune Checkpoint Blockade in Cancer Research

• Promotion of T Cell Activation: In vivo, 9H10 is primarily used to block the interaction between CTLA-4 and its ligands (CD80/CD86, also known as B7-1/B7-2). By preventing this interaction, 9H10 disinhibits T cell activation, allowing co-stimulation via CD28, which enhances anti-tumor immune responses.
• Syngeneic Tumor Models: The antibody has been administered intravenously in murine syngeneic tumor models (e.g., CT26 colon carcinoma) to assess its impact on tumor growth. Dosing regimens commonly involve multiple intravenous injections, and the treatment has been associated with varied tumor response rates, including complete regression in some animals, reflecting the heterogeneity of immune responses even in genetically identical mice.
• Quantitative Analysis: Systems pharmacology modeling with 9H10 has provided insights into dose–response relationships, revealing that higher doses correlate with increased rates of complete tumor regression, though the kinetics of tumor progression and regression are not strictly dose-dependent.

Broader Immunological Studies

• Investigation of Immune Tolerance and Autoimmunity: Because CTLA-4 is critical for maintaining immune tolerance and preventing autoimmunity, 9H10 has been used in vivo to study mechanisms of immune dysregulation. CTLA-4-deficient mice develop fatal lymphoproliferative disorders, highlighting the molecule’s role as a negative regulator of immunity.
• Preclinical Evaluation of Immunotherapies: As CTLA-4 is a target for cancer immunotherapy, 9H10 serves as a murine analog to human CTLA-4-blocking therapeutics, aiding in the preclinical evaluation of immune checkpoint blockade strategies.

Technical Considerations

• Antibody Preparation: For in vivo use, 9H10 is typically supplied in high-purity, low-endotoxin formulations suitable for injection in mice.
• Application Flexibility: While its main use is in vivo functional blockade, 9H10 is also validated for techniques such as flow cytometry and western blotting, though these are principally in vitro or ex vivo applications.

Summary Table: Key In Vivo Applications of Clone 9H10

Conclusion

Clone 9H10 is a critical tool in mouse immunology, especially for studying the effects of CTLA-4 blockade on T cell activation, tumor immunity, and immune tolerance. Its most common in vivo application is in syngeneic tumor models to evaluate the therapeutic potential of immune checkpoint inhibition, providing foundational insights for translational cancer immunotherapy research.

In the literature, 9H10 (anti-CTLA-4) is commonly used alongside several other antibodies and proteins, especially in immunotherapy and immune regulation studies. Frequently paired antibodies include 9D9 and UC10-4F10-11, which are also anti-mouse CTLA-4 clones utilized in similar research contexts.

Other commonly used antibodies or proteins with 9H10 are:

• 9D9: Another hamster anti-mouse CTLA-4 antibody, used in various tumor models, sometimes together with 9H10 for comparative or combination studies.
• UC10-4F10-11 and 4F10: Rat anti-mouse CTLA-4 antibodies, which help researchers explore mechanisms of CTLA-4 blockade and are sometimes used in combination therapies with 9H10.
• Anti-CD28 (targeting CD28 co-stimulatory receptor): Since CTLA-4 and CD28 compete for binding to B7-1 (CD80) and B7-2 (CD86), anti-CD28 may be included to study their interactions in T cell responses.
• Anti-PD-1/PD-L1 antibodies: These checkpoint inhibitors can be combined with 9H10 in studies investigating synergistic effects in immune checkpoint blockade therapies, although specific co-usage should be verified in the experimental setup.
• B7 family proteins (CD80/CD86): These are the natural ligands for CTLA-4 and CD28; studies involving 9H10 often measure or manipulate their expression to assess immune activation or inhibition.

For influenza research, 9H10 has a separate context as an anti-hemagglutinin stem antibody. In these cases, related antibodies include:

• CR8020 and CR8043: These also target the stalk region of influenza hemagglutinin and are compared or combined in structural and functional studies with 9H10.

Overall, the most common combinations in the context of CTLA-4 and immune checkpoint blockade research are 9H10, 9D9, and UC10-4F10-11/4F10, with frequent inclusion of other immune regulatory proteins for functional studies. If your interest is in influenza or other applications, pairing will more likely involve anti-hemagglutinin stalk antibodies such as CR8020 and CR8043.

Clone 9H10 is a widely used anti-mouse CTLA-4 monoclonal antibody in immunology and cancer immunotherapy research. Its key findings in scientific literature include:

• Selective depletion of intratumoral regulatory T cells (Tregs): 9H10 effectively depletes Tregs within tumors, reversing local immune suppression and enhancing antitumor immunity. This depletion is specific to the tumor microenvironment and does not occur in peripheral tissues such as spleen or lymph nodes.

• Antibody-dependent cellular cytotoxicity (ADCC) mechanisms: 9H10’s efficacy relies heavily on Fcγ receptor engagement, notably FcγRIV, which mediates the depletion of intratumoral Tregs through ADCC. Compared to other anti-CTLA-4 clones (such as 9D9), 9H10 binds more avidly to FcγRIV, correlating with greater Treg depletion potency.

• Robust antitumor memory response: Treatment with 9H10 generates a strong memory response compared to both other CTLA-4 antibody clones and anti-PD-1 therapies. Mice treated with 9H10 showed minimal tumor regrowth upon rechallenge, highlighting its ability to enhance durable antitumor immunity.

• CTLA-4 blockade and T cell co-stimulation: 9H10 blocks CTLA-4 interaction with its ligands (such as B7), permitting enhanced CD28-mediated T cell co-stimulation and activation.

• Functional importance of Fc domain: The antitumor efficacy of 9H10 (and similar antibodies) in vivo is dependent on its Fc domain. Fc-modified variants or antibody fragments lacking this domain show markedly reduced efficacy, confirming that mere CTLA-4 blockade is insufficient without Fc-dependent Treg depletion.

• Specificity and related clones: 9H10’s effects are largely specific among anti-CTLA-4 clones, but similar, though sometimes less potent, results can be achieved with other clones such as 9D9 and UC10-4F10. Differences between clones are primarily attributed to variations in FcγR binding and resulting ADCC efficacy.

• Notable limitations: In some experimental settings, 9H10’s ability to deplete intratumoral Tregs is present, but the overall impact on tumor growth can be context-dependent, especially when Treg levels are minimally affected.

In summary, clone 9H10’s major scientific contributions are its use as a model anti-CTLA-4 antibody capable of effectively depleting intratumoral Tregs via ADCC, augmenting memory T-cell responses, and providing insights into the mechanistic importance of the Fc domain for checkpoint blockade therapies.

Dosing regimens for clone 9H10 (anti-CTLA-4) in mouse models are highly variable, depending on the tumor model, experimental endpoint, administration route, and combination therapies, but certain standards have emerged.

• Standard Dose Range:
  The most commonly reported doses are 100–200 µg per mouse administered intraperitoneally every ~3 days for 3–4 total doses.

• In Syngeneic Tumor Models:

  • 200 µg for initial injection, followed by 100 µg for subsequent injections (usually three additional doses).
  • Some protocols use 100–200 µg per dose across all injections, given every 3 days, typically intraperitoneally.

• Alternative Dosing Strategies:

  • Dose by body weight: Some studies use 0.625–10 mg/kg intravenously every 3 days for three doses (Q3Dx3), especially in pharmacology or systems modeling settings.
  • Low-dose regimens: In some models (e.g., combination therapy, dual-tumor mouse models), very low doses such as 10–30 µg intratumorally or intraperitoneally may be used, especially to limit toxicity.
  • Combination regimens: When combined with other checkpoint inhibitors (like anti-PD-1), dosing is often maintained in the same 100–200 µg intraperitoneal range, at intervals of 3 days.

• Route of Administration:

  • Intraperitoneal injection is most common.
  • Intravenous and intratumoral injection have been used, especially in mechanistic or pharmacodynamic studies.

• Toxicity Considerations:

  • Higher or more frequent doses (e.g., >200 µg or >4 doses) can increase the risk of immune-related toxicity, while doses around 10–30 µg can be effective and minimize adverse effects in certain models.

In summary, clone 9H10 is most frequently dosed at 100–200 µg per mouse every three days by intraperitoneal injection for 3–4 doses, but doses can range from 10 µg (for local or combination regimens with lower toxicity risk) to 10 mg/kg (IV, for pharmacokinetic modeling), and adjustments are made based on specific mouse models and study goals.