Murine Anti-mCTLA4 mAb

Recombinant mouse mAb against murine CTLA-4 for in vivo use

Effect of Anti-CTLA4 on T cell activation

Anti-mCTLA4-mIgG2a InvivoFit™ is a mouse anti-mouse monoclonal antibody (mAb) featuring the variable region of the previously described anti-mCTLA-4 9D9 mAb [1] and a murine IgG2a constant region. The 9D9 mAb has a sequence that is 100% murine (constant and variable regions), ensuring minimal immunogenicity upon repeated injections into mice. This mAb targets murine cytotoxic T-lymphocyte-associated protein 4 (mCTLA-4) and blocks CTLA4-mediated negative signals downregulating T cell activation.  Thus, anti-mCTLA-4 mAb unleashes T cell activity [1, 2].Notably, the 9D9 mAb, along with most commercially available anti-mCTLA4 mAbs feature the IgG2b isotype which displays low antitumor activity in vivo [2]. To overcome this issue, Anti-mCTLA4-mIgG2a InvivoFit™ was generated by recombinant technology and features the murine IgG2a isotype, which mediates potent cytotoxic functions. Anti-mCTLA4-mIgG2a is provided in an InvivoFit™ grade, a high-quality standard specifically adapted to in vivo studies.

Key features of Anti-mCTLA4-mIgG2a InvivoFit™:

• Sequence is 100% murine
• Features the IgG2a isotype (associated with high antitumor activity)
• Guaranteed sterile, endotoxin level < 1 EU/mg
• Specifically designed for in vivo studies in mice
• Low aggregation < 5%
• Produced in both animal-free facilities and defined media

Anti-mCTLA4-mIgG2a InvivoFit™ is produced in Chinese hamster ovary (CHO) cells, purified by affinity chromatography with protein A, and it"s binding to mCTLA-4 is validated using ELISA.

References:

1. Selby MJ. et al., 2013. Anti-CTLA-4 antibodies of IgG2a isotype enhance antitumor activity through reduction of intratumoral regulatory T cells. Cancer Immunol Res. 1(1):32-42.2. Ribas A. & Wolchock J.D., 2018. Cancer immunotherapy using checkpoint blockade. Science. 359:1350-55.

Figures

ELISA binding of Anti-mCTLA4-mIgG2a InvivoFit™ to recombinant murine CTLA-4.

A dilution series of Anti-mCTLA4-mIgG2a InvivoFit™ and anti-mCTLA4 (9D9 clone) was used for the detection of coated mCTLA-4 antigen at 5  µg/ml. Detection of bound antibody was performed using an HRP‑conjugated anti‑murine κ-light chain secondary antibody.  HRP activity was assessed by a colorimetric assay using Tetramethylbenzidine (TMB) substrate. Optical density was measured at 490 nm. Data are shown as percentage absorbance.

Specifications

Specificity: Targets cells expressing murine CTLA-4

Formulation: Lyophilized from 0.2 μm filtered solution in 150 mM sodium chloride, 20 mM sodium phosphate buffer with 5% saccharose

Clonality: Monoclonal antibody

Isotype: Murine IgG2a, kappa

Source: CHO cells

Purity: Purified by affinity chromatography with protein A

Tested application: ELISA

Quality control:

• Binding confirmed using ELISA
• The complete sequence of this antibody has been verified
• < 5% aggregates (confirmed by size exclusion chromatography)
• Guaranteed sterile and <1 EU/mg (determined by the LAL assay)

Contents

Anti-mCTLA4-mIgG2a InvivoFit™ is provided sterile, endotoxin-free, azide-free and lyophilized.  

This product is available in two pack sizes:

• mctla4-mab10-1​: 1 mg
• mctla4-mab10-10​: 10 mg

 Product is shipped at room temperature.

 Store lyophilized antibody at -20 °C.

 Lyophilized product is stable for at least 1 year

 Avoid repeated freeze-thaw cycles.

Details

The cytotoxic T-lymphocyte-associated protein 4 (CTLA-4, also known as CD152) is an inhibitory receptor expressed on activated T lymphocytes. T-cell activation requires two signals. Signal 1 is delivered upon interaction of the T cell receptor (TCR) with antigenic peptides bound to major histocompatibility complex (MHC) molecules on antigen-presenting cells (APCs). Signal 2 is delivered upon interaction of the co-stimulatory receptor CD28 with the B7 family ligands, B7-1 (CD80) and B7-2 (CD86), on APCs.CTLA-4 is an immune checkpoint molecule upregulated upon T cell activation. It exerts competitive binding to CD28 ligands, thereby preventing T-cell overstimulation. CTLA-4 blockade with monoclonal antibodies (mAbs) has been used to treat patients with metastatic melanoma.