CTLA-4 Blockade Assay

Creative Biolabs is a first-class service provider focused on antibody development and antibody functional assays. CTLA-4 blockade assay is an effective method which enables to measure the activity of antibody targeting CTLA-4 and to explore the mechanism of action (MOA) of biologics designed to block CTLA-4. Aided by experienced experts and advanced technology platforms, we are confident in providing first-in-class CTLA-4 blockade assays.

Introduction to CTLA-4

Cytotoxic T-lymphocyte associated protein 4 (CTLA-4), also known as CD152, is an immune inhibitory receptor expressed on CD4⁺ T cells that competitively binds CD80 (B7.1) and CD86 (B7.2) to downregulate T cell activity. CTLA-4 has been identified as the counterpart of the co-stimulatory B7-CD28 pathway. It highly expressed on the surface of T cells binds to B7 with higher avidity than CD28, and thus outcompetes the positive co-stimulatory signal from CD28. Furthermore, CTLA-4 binding with its ligands, CD80 (B7-1) or CD86 (B7-2) on an adjacent antigen presenting cell (APC) can inhibit CD28 co-stimulation of T cell activation, cell proliferation, and cytokine production. Indeed, cross-linking of CTLA-4 molecules on the cell surface leads to a decreased T cell proliferation and IL-2 production. As thus, CTLA-4 plays an essential role in regulating immune responses to tumor antigens and autoantigens. It has been shown as a key target in drug discovery for cancer and blocking it can reduce tumor size. With the success of CTLA-4 immunotherapy drug, other new therapeutic antibodies and Fc fusion proteins blocking the CTLA-4/CD80 and CD86 interaction have been shown as promising therapeutic drugs for the treatment of a variety of cancers.

Fig.1 Cellular expression of CTLA-4 and Foxp3.¹

CTLA-4 Blockade Assay

CTLA-4 blockade assay is a bioluminescent cell-based assay that overcomes the limitations of current methods (such as complex assay protocols, unqualified assay reagents, and independent of donor primary cells). This test can be used to measure the potency and stability of antibodies and other biologics targeting CTLA-4. Besides, it is also used to describe the MOA of biologics designed to block the interaction of CTLA-4 with its ligands, CD80 and CD86. Creative Biolabs has accumulated extensive experience in antibody functional assays. We are proud to offer high-quality CTLA-4 blockade assay services for both antibodies and other biologics to global customers. Our services are characterized by:

• Excellent expert team for offering real-time technical guidance
• Advanced assay platform to promote the data output
• Timely data feedback to facilitate the process of your project

CTLA-4 Products

Leveraging our robust immunology platform and years of project experience, Creative Biolabs has developed numerous convenient kits and cell lines to facilitate the application expansion of CTLA-4-based therapeutic solutions into clinical treatment. Listed below are several popular kits and cells of CTLA-4 that are frequently purchased by customers. Click the link or contact us for more about them.

Data Show

This study utilized human CTLA4 gene knock-in mice and mice reconstituted with human hematopoietic stem cells to systematically assess the necessity of blocking the B7-CTLA-4 interaction for the immunotherapeutic efficacy of anti-human CTLA-4 monoclonal antibodies under physiologically relevant conditions. The results imply that obstructing the B7-CTLA-4 interaction may not be crucial for the cancer immunotherapeutic effect.

Fig.2 The blocking activity comparison of anti-CTLA-4 antibodies for B7-1-CTLA-4 and B7-2-CTLA-4 interactions.²

Fig.3 The activity comparison of anti-CTLA-4 antibodies in B7/CTLA-4-mediated cell-cell interactions.²

With the years of experience in the field of antibody functional assays, Creative Biolabs is specialized in offering high-quality functional assays for antibodies targeting CTLA-4. We are dedicated to providing reliable results for your project, thereby facilitating the clinical application transformation of your antibody drugs. For more detailed information, please feel free to contact us or directly sent us an inquiry.

References

1. Walker, L.S. Treg and CTLA-4: two intertwining pathways to immune tolerance. Journal of Autoimmunity. 2013, 45(100):49-57.
   Distributed under Open Access License CC BY 3.0, without modification.
2. Du, Xuexiang, et al. "A reappraisal of CTLA-4 checkpoint blockade in cancer immunotherapy." Cell Research 28.4 (2018): 416-432.
   Distributed under Open Access License CC BY 4.0, without modification.

For Research Use Only.