Catalog No.	PA007380.m2aLA
Product Name	Anti-mouse CTLA-4 Antibody (Clone: 9D9, CD152) | PA007380.m2aLA
Supplier Name	Syd Labs, Inc.
Brand Name	Syd Labs
Synonyms	cytotoxic T-lymphocyte associated antigen 4, cytotoxic T-lymphocyte antigen 4, CD152, CTLA4
Summary	The in vivo grade recombinant mouse monoclonal antibody (clone: 9D9) specifically binds to the mouse CTLA-4 protein.
Uniprot ID	CD152 on UniProt.org
Gene ID	12477
Clone	9D9
Isotype	Mouse IgG2a kappa
Specificity/Sensitivity	The in vivo grade recombinant mouse monoclonal antibody (clone: 9D9) specifically binds to the mouse CTLA-4 protein.
Applications	ELISA, flow cytometry, neutralization, functional assays such as bioanalytical PK and ADA assays, and those assays for studying biological pathways affected by the mouse CTLA-4 protein.
Form Of Antibody	0.2 uM filtered solution, pH 7.4, no stabilizers or preservatives.
Endotoxin	< 1 EU per 1 mg of the protein by the LAL method.
Purity	>95% by SDS-PAGE under reducing conditions.
Shipping	The antibody is shipped with ice pack. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage	Use a manual defrost freezer and avoid repeated freeze-thaw cycles. 12 months from date of receipt, -20 to -70°C as supplied. 1 month from date of receipt, 2 to 8°C as supplied.
Note	Recombinant mouse IgG2b isotype control, Recombinant mouse IgG2c LALAPG isotype control, and Recombinant mouse IgG2a LALAPG isotype control are available. Condition of sample preparation and optimal sample dilution should be determined experimentally by the investigator.
Order Offline	Phone: 1-617-401-8149 Fax: 1-617-606-5022 Email: message@sydlabs.com Or leave a message with a formal purchase order (PO) Or credit card.

Description

PA007380.m2aLA: Recombinant Anti-mouse CTLA-4 Monoclonal Antibody(Clone: 9D9), Mouse IgG2a-L234A L235A P329G (LALAPG) Kappa，In vivo Grade

Background

The 9D9 antibody blocks the mouse cytotoxic T lymphocyte antigen-4 (CTLA-4). Blocking CTLA-4 removes an inhibitory signal from reducing the activity of T lymphocytes.

Cytotoxic T-lymphocyte antigen-4 (CTLA-4) is an inhibitory molecule that competes with the stimulatory CD28 for binding to B7 on antigen presenting cells. CTLA-4 and CD28 are both presented on the surface of T-cells.

References for Anti-mouse CTLA-4 Antibody(9D9)

1、Leukemic B Cell CTLA-4 Suppresses Co-stimulation of T cells
Priscilla Do,et al.J Immunol. 2020.PMCID: PMC6478536
“Clinical benefit of anti-mouse CTLA-4 antibody blockade on T cells is known, yet the impact of its expression on cancer cells remains unaddressed. We define an immunosuppressive role for tumor expressed CTLA-4 using chronic lymphocytic leukemia (CLL) as a disease model. CLL, among other cancer cells, are CTLA-4+. Co-culture with activated human T cells induced surface CTLA-4 on primary human CLL B cells. CTLA-4 on CLL-derived human cell lines decreased CD80 expression on co-cultured CD80+ cells, with restoration upon CTLA-4 blockade. Co-culture of CTLA-4+ CLL cells with CD80-GFP+ cell lines revealed transfer of CD80-GFP into CLL tumor cells, similar to CTLA-4+ T cells able to trans-endocytose CD80. Co-culture of T cells with CTLA-4+ CLL cells decreased IL2 production. Using a human CTLA-4 knock-in mouse lacking FcγR function, anti-tumor efficacy was observed by blocking murine CTLA-4 on tumor cells in isolation of the T cell effect and Fc-mediated depletion. These data implicate tumor CTLA-4 in cancer cell-mediated immunosuppression in vitro and to have a functional role on tumor cells in vivo.”

2、Activity of murine surrogate antibodies for durvalumab and tremelimumab lacking effector function and the ability to deplete regulatory T cells in mouse models of cancer
Darren J Schofield,et al.MAbs. 2021.PMCID: PMC7831362
“Preclinical studies of PD-L1 and anti-mouse CTLA-4 antibody blockade have relied heavily on mouse syngeneic tumor models with intact immune systems, which facilitate dissection of immunosuppressive mechanisms in the tumor microenvironment. Commercially developed monoclonal antibodies (mAbs) targeting human PD-L1, PD-1, and CTLA-4 may not demonstrate cross-reactive binding to their mouse orthologs, and surrogate anti-mouse antibodies are often used in their place to inhibit these immune checkpoints. In each case, multiple choices exist for surrogate antibodies, which differ with respect to species of origin, affinity, and effector function. To develop relevant murine surrogate antibodies for the anti-human PD-L1 mAb durvalumab and the anti-human CTLA-4 mAb tremelimumab, rat/mouse chimeric or fully murine mAbs engineered for reduced effector function were developed and compared with durvalumab and tremelimumab. Characterization included determination of target affinity, in vivo effector function, pharmacokinetic profile, and anti-tumor efficacy in mouse syngeneic tumor models. Results showed that anti–PD-L1 and anti–CTLA-4 murine surrogates with pharmacologic properties similar to those of durvalumab and tremelimumab demonstrated anti-tumor activity in a subset of commonly used mouse syngeneic tumor models. This activity was not entirely dependent on antibody-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis effector function, or regulatory T-cell depletion, as antibodies engineered to lack these features showed activity in models historically sensitive to checkpoint inhibition, albeit at a significantly lower level than antibodies with intact effector function.”

3、The CTLA-4 x OX40 bispecific antibody ATOR-1015 induces anti-tumor effects through tumor-directed immune activation
Anne Månsson Kvarnhammar,et al.J Immunother Cancer. 2019.PMCID: PMC6458634
“Background
The CTLA-4 blocking antibody ipilimumab has demonstrated substantial and durable effects in patients with melanoma. While anti-mouse CTLA-4 antibody therapy, both as monotherapy and in combination with PD-1 targeting therapies, has great potential in many indications, the toxicities of the current treatment regimens may limit their use. Thus, there is a medical need for new CTLA-4 targeting therapies with improved benefit-risk profile.
Methods
ATOR-1015 is a human CTLA-4 x OX40 targeting IgG1 bispecific antibody generated by linking an optimized version of the Ig-like V-type domain of human CD86, a natural CTLA-4 ligand, to an agonistic OX40 antibody. In vitro evaluation of T-cell activation and T regulatory cell (Treg) depletion was performed using purified cells from healthy human donors or cell lines. In vivo anti-tumor responses were studied using human OX40 transgenic (knock-in) mice with established syngeneic tumors. Tumors and spleens from treated mice were analyzed for CD8+ T cell and Treg frequencies, T-cell activation markers and tumor localization using flow cytometry.
Results
ATOR-1015 induces T-cell activation and Treg depletion in vitro. Treatment with ATOR-1015 reduces tumor growth and improves survival in several syngeneic tumor models, including bladder, colon and pancreas cancer models. It is further demonstrated that ATOR-1015 induces tumor-specific and long-term immunological memory and enhances the response to PD-1 inhibition. Moreover, ATOR-1015 localizes to the tumor area where it reduces the frequency of Tregs and increases the number and activation of CD8+ T cells.
Conclusions
By targeting CTLA-4 and OX40 simultaneously, ATOR-1015 is directed to the tumor area where it induces enhanced immune activation, and thus has the potential to be a next generation CTLA-4 targeting therapy with improved clinical efficacy and reduced toxicity. ATOR-1015 is also expected to act synergistically with anti-PD-1/PD-L1 therapy. The pre-clinical data support clinical development of ATOR-1015, and a first-in-human trial has started (NCT03782467).”

4、Prophylactic IL-23 blockade uncouples efficacy and toxicity in dual CTLA-4 and PD-1 immunotherapy
Mingyi Ju,et al.J Immunother Cancer. 2024.PMCID: PMC11293404
“Background
Immune-related adverse events (irAEs), characterized by targeted inflammation, occur in up to 60% of patients with melanoma treated with immune checkpoint inhibitors (ICIs). Evidence proved that the baseline peripheral blood profiles of patients at risk for severe irAEs development paralleled clinical autoimmunity. Interleukin (IL)-23 blockade with risankizumab is recommended for cases that are suffering from autoimmune disease, such as autoimmune colitis. However, currently, the role of IL-23 in irAEs onset and severity remains poorly understood.
Methods
The pro-inflammatory cytokines most associated with severe irAEs onset were identified by retrospective analysis based on GSE186143 data set. To investigate the efficacy of prophylactic IL-23 blockade administration to prevent irAEs, refer to a previous study, we constructed two irAEs murine models, including dextran sulfate sodium salt (DSS)-induced colitis murine model and a combined-ICIs-induced irAEs murine model. To further explore the applicability of our findings, murine models with graft-versus-host disease were established, in which Rag2−/−Il2rg−/− mice were transferred with human peripheral blood mononuclear cells and received combined cytotoxic T-lymphocyte associated antigen 4 (CTLA-4) and programmed cell death protein-1 (PD-1) treatment. Human melanoma cells were xenografted into these mice concomitantly.
Results
Here we show that IL-23 was upregulated in the serum of patients suffering from irAEs after dual anti-CTLA-4 and anti-PD-1 treatment, and increased as a function of irAEs severity. Additionally, Augmented CD4+ Tems may preferentially underlie irAEs onset. Treating mice with anti-mouse IL-23 antibody concomitantly with combined CTLA-4 and PD-1 immunotherapy ameliorates colitis and, in addition, preserves antitumor efficacy. Moreover, in xenografted murine models with irAEs, prophylactic blockade of human IL-23 using clinically available IL-23 inhibitor (risankizumab) ameliorated colitis, hepatitis and lung inflammation, and moreover, immunotherapeutic control of tumors was retained. Finally, we also provided a novel machine learning-based computational framework based on two blood-based features—IL-23 and CD4+ Tems—that may have predictive potential for severe irAEs and ICIs response.
Conclusions
Our study not only provides clinically feasible strategies to dissociate efficacy and toxicity in the use of combined ICIs for cancer immunotherapy, but also develops a blood-based biomarker that makes it possible to achieve a straightforward and non-invasive, detection assay for early prediction of irAEs onset.”

5、CTLA-4 blockade drives loss of Treg stability in glycolysis-low tumors
Roberta Zappasodi,et al.Nature. 2021.PMCID: PMC8057670
“Limiting the metabolic competition in the tumor microenvironment (TME) may increase the effectiveness of immunotherapy. Because of its critical role in glucose metabolism of activated T cells, CD28 signaling has been proposed as a T-cell metabolic biosensor1. Conversely, CTLA-4 engagement has been shown to down-regulate T-cell glycolysis1. Here, we investigated the impact of anti-mouse CTLA-4 antibody blockade on the metabolic fitness of intra-tumor T cells in relationship to the tumor glycolytic capacity. We found that CTLA-4 blockade promotes immune cell infiltration and metabolic fitness especially in glycolysis-low tumors. Accordingly, anti-CTLA-4 achieved better therapeutic outcomes in mice bearing glycolysis-defective tumors. Intriguingly, tumor-specific CD8+ T-cell responses correlated with phenotypic and functional destabilization of tumor-infiltrating regulatory T cells (Tregs) toward IFN-γ- and TNF-α-producing cells in glycolysis-defective tumors. By mimicking the highly and poorly glycolytic TME in vitro, we show that the effect of CTLA-4 blockade to promote Treg destabilization is dependent on Treg glycolysis and CD28 signaling. These findings indicate that decreasing tumor competition for glucose may facilitate the therapeutic activity of CTLA-4 blockade, thus supporting its combination with inhibitors of tumor glycolysis. Moreover, these results reveal a new mechanism through which anti-CTLA-4 interferes with Treg function in the presence of glucose.”

6、Botensilimab, an Fc-Enhanced Anti–CTLA-4 Antibody, Is Effective against Tumors Poorly Responsive to Conventional Immunotherapy
Dhan Chand,et al.Cancer Discov. 2024.PMCID: PMC11609826
“Conventional immune checkpoint inhibitors (ICI) targeting cytotoxic T-lymphocyte antigen 4 (anti-mouse CTLA-4 antibody) elicit durable survival but primarily in patients with immune-inflamed tumors. Although the mechanisms underlying response to anti–CTLA-4 remain poorly understood, Fc-gamma receptor (FcγR) IIIA coengagement seems critical for activity, potentially explaining the modest clinical benefits of approved anti–CTLA-4 antibodies. We demonstrate that anti–CTLA-4 engineered for enhanced FcγR affinity leverages FcγR-dependent mechanisms to potentiate T-cell responsiveness, reduce intratumoral regulatory T cells, and enhance antigen-presenting cell activation. Fc-enhanced anti–CTLA-4 promoted superior efficacy in mouse models and remodeled innate and adaptive immunity versus conventional anti–CTLA-4. These findings extend to patients treated with botensilimab, an Fc-enhanced anti–CTLA-4 antibody, with clinical activity across multiple poorly immunogenic and ICI treatment–refractory cancers. Efficacy was independent of tumor neoantigen burden or FCGR3A genotype. However, FCGR2A and FCGR3A expression emerged as potential response biomarkers. These data highlight the therapeutic potential of Fc-enhanced anti–CTLA-4 antibodies in cancers unresponsive to conventional ICI therapy.”

7、Synthetic DNA-encoded monoclonal antibody delivery of anti-CTLA-4 antibodies induces tumor shrinkage in vivo
Elizabeth K Duperret,et al.Cancer Res. 2019.PMCID: PMC6239932
“Antibody-based immune therapies targeting the T cell checkpoint molecules anti-mouse CTLA-4 antibody and PD-1 have impacted cancer therapy. However, this immune therapy requires complex manufacturing and frequent dosing, limiting the global use of this treatment. Here we focused on the development of a DNA-encoded monoclonal antibody (DMAb) approach for delivery of anti-CTLA-4 monoclonal antibodies in vivo. With this technology, engineered and formulated DMAb plasmids encoding IgG inserts were directly injected into muscle and delivered intracellularly by electroporation, leading to in vivo expression and secretion of the encoded IgG. DMAb expression from a single dose can continue for several months without the need for repeated administration. Delivery of an optimized DMAb encoding anti-mouse CTLA-4 IgG resulted in high serum levels of the antibody as well as tumor regression in Sa1N and CT26 tumor models. DNA-delivery of the anti-human CTLA-4 antibodies ipilimumab and tremelimumab in mice achieved potent peak levels of approximately 85μg/mL and 58μg/mL, respectively. These DMAb exhibited prolonged expression, with maintenance of serum levels at or above 15μg/mL for over a year. Anti-human CTLA-4 DMAbs produced in vivo bound to human CTLA-4 protein expressed on stimulated human PBMC and induced T cell activation in a functional assay ex vivo. In summary, direct in vivo expression of DMAb encoding checkpoint inhibitors serve as a novel tool for immunotherapy that could significantly improve availability and provide broader access to such therapies.”

8、High Antigenicity for Treg Cells Confers Resistance to PD‐1 Blockade Therapy via High PD‐1 Expression in Treg Cells
Hiroaki Matsuura,et al.Cancer Sci. 2025.PMCID: PMC12044662
“Regulatory T (Treg) cells have an immunosuppressive function, and programmed death‐1 (PD‐1)‐expressing Treg cells reportedly induce resistance to PD‐1 blockade therapies through their reactivation. However, the effects of antigenicity on PD‐1 expression in Treg cells and the resistance to PD‐1 blockade therapy remain unclear. Here, we show that Treg cells gain high PD‐1 expression through an antigen with high antigenicity. Additionally, tumors with high antigenicity for Treg cells were resistant to PD‐1 blockade in vivo due to PD‐1+ Treg‐cell infiltration. Because such PD‐1+ Treg cells have high cytotoxic T lymphocyte antigen (CTLA)‐4 expression, resistance could be overcome by combination with an anti‐CTLA‐4 monoclonal antibody (mAb). Patients who responded to combination therapy with anti‐PD‐1 and anti‐CTLA‐4 mAbs sequentially after primary resistance to PD‐1 blockade monotherapy showed high Treg cell infiltration. We propose that the high antigenicity of Treg cells confers resistance to PD‐1 blockade therapy via high PD‐1 expression in Treg cells, which can be overcome by combination therapy with an anti‐CTLA‐4 mAb.”

9、A reappraisal of CTLA-4 checkpoint blockade in cancer immunotherapy
Xuexiang Du,et al.Cell Res. 2018.PMCID: PMC5939050
“It is assumed that anti-CTLA-4 antibodies cause tumor rejection by blocking negative signaling from B7-CTLA-4 interactions. Surprisingly, at concentrations considerably higher than plasma levels achieved by clinically effective dosing, the anti-CTLA-4 antibody Ipilimumab blocks neither B7 trans-endocytosis by CTLA-4 nor CTLA-4 binding to immobilized or cell-associated B7. Consequently, Ipilimumab does not increase B7 on dendritic cells (DCs) from either CTLA4 gene humanized (Ctla4h/h) or human CD34+ stem cell-reconstituted NSG™ mice. In Ctla4h/m mice expressing both human and mouse CTLA4 genes, anti-CTLA-4 antibodies that bind to human but not mouse CTLA-4 efficiently induce Treg depletion and Fc receptor-dependent tumor rejection. The blocking antibody L3D10 is comparable to the non-blocking Ipilimumab in causing tumor rejection. Remarkably, L3D10 progenies that lose blocking activity during humanization remain fully competent in inducing Treg depletion and tumor rejection. Anti-B7 antibodies that effectively block CD4 T cell activation and de novo CD8 T cell priming in lymphoid organs do not negatively affect the immunotherapeutic effect of Ipilimumab. Thus, clinically effective anti-CTLA-4 mAb causes tumor rejection by mechanisms that are independent of checkpoint blockade but dependent on the host Fc receptor. Our data call for a reappraisal of the CTLA-4 checkpoint blockade hypothesis and provide new insights for the next generation of safe and effective anti-CTLA-4 mAbs.”

10、Blockade of CTLA-4 on both effector and regulatory T cell compartments contributes to the antitumor activity of anti–CTLA-4 antibodies
Karl S Peggs,et al.J Exp Med. 2009.PMCID: PMC2722174
“Cytotoxic T lymphocyte–associated antigen 4 (CTLA-4) is a critical negative regulator of immune responses. Uniquely among known inhibitory receptors, its genetic ablation results in a fulminating and fatal lymphoproliferative disorder. This central regulatory role led to the development of antibodies designed to block CTLA-4 activity in vivo, aiming to enhance immune responses against cancer. Despite their preclinical efficacy and promising clinical activity against late stage metastatic melanoma, the critical cellular targets for their activity remains unclear. In particular, debate has focused on whether the effector T cell (Teff) or regulatory T cell (T reg cell) compartment is the primary target of antibody-mediated blockade. We developed a mouse expressing human instead of mouse CTLA-4, allowing us to evaluate the independent contributions of CTLA-4 blockade of each T cell compartment during cancer immunotherapy in an in vivo model of mouse melanoma. The data show that although blockade on effector cells significantly improves tumor protection, unicompartmental blockade on regulatory cells completely fails to enhance antitumor responses. However, concomitant blockade of both compartments leads to a synergistic effect and maximal antitumor activity. We conclude that the combination of direct enhancement of Teff cell function and concomitant inhibition of T reg cell activity through blockade of CTLA-4 on both cell types is essential for mediating the full therapeutic effects of anti–CTLA-4 antibodies during cancer immunotherapy.”

Related Recombinant IgG Reference Antibodies:
Recombinant mouse lgG2b isotype control antibody
Recombinant mouse IgG2c LALAPG isotype control antibody
Recombinant mouse IgG2a LALAPG isotype control antibody

Syd Labs provides the following research grade anti-CTLA-4 antibody biosimilars:
Ipilimumab Biosimilar, research grade, anti-human CTLA-4 monoclonal antibody
Tremelimumab Biosimilar, research grade, anti-human CTLA-4 monoclonal antibody

Recombinant CTLA-4 Proteins:
Biotinylated Human CTLA-4 Protein
Cynomolgus CTLA-4 Protein
Human CTLA-4 Protein

Anti-mouse CTLA-4 Antibody(9D9) from: Recombinant Anti-mouse CTLA-4 Monoclonal Antibody(Clone: 9D9), Mouse IgG2a-L234A L235A P329G (LALAPG) Kappa, In vivo Grade: PA007380.m2aLA Syd Labs

No more offers for this product!