Immune Checkpoint Blockade: Blocking Antibodies

Blocking antibodies for immune checkpoint targets used in cancer immunotherapy research

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Blockade of immune checkpoint molecules, such as CTLA-4 and PD-1/PD-L1, is a promising therapeutic approach for cancer immunotherapy. Unfortunately, blocking CTLA-4 or PD-1/PD-L1 is not universally successful across different cancer types and patients. It is thought that co-targeting multiple checkpoint molecules simultaneously could improve the effectiveness of this strategy. Take advantage of the best blocking antibodies on the market to identify the next key immune checkpoint target. View our selection of immune checkpoint blocking antibodies.


R&D Systems® Blocking Antibodies

Our wide target selection and high quality of blocking antibodies are unmatched. By utilizing our in-house manufactured proteins, we have the ability to test all of our blocking antibodies in relevant bioassays specific for each target. These assays include proliferation, chemotaxis, protein secretion, adhesion, and in vitro enzyme neutralization. By manufacturing and testing our blocking antibodies, we are able to ensure low endotoxin levels so you can always be confident in their performance. Learn more about what makes our blocking antibodies the best.

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CTLA-4 Inhibition of B7-1/CD80-induced IL-2 Secretion and Neutralization by Mouse CTLA-4 Antibody.
Recombinant Mouse CTLA-4 Fc Chimera (Catalog # 434-CT) inhibits Recombinant Human B7-1/CD80 Fc Chimera (Catalog # 10133-B1) induced IL-2 secretion in the Jurkat human acute T cell leukemia cell line in a dose-dependent manner (orange line), as measured by the Human IL-2 Quantikine® ELISA Kit (Catalog # D2050). Inhibition of Recombinant Human B7-1/CD80 Fc Chimera (3 µg/mL) activity elicited by Recombinant Mouse CTLA-4 Fc Chimera (1 µg/mL) is neutralized (green line) by increasing concentrations of Mouse CTLA-4 Monoclonal Antibody (Catalog # MAB434).The ND50 is typically 2.5-10 µg/mL in the presence of PHA (10 µg/mL).

CTLA-4 inhibition of B7-1 induced IL-2 secretion is neutralization by Mouse CTLA-4 Antibody


VISTA/B7-H5/PD-1H Binding to VSIG3 Blocked by Human VISTA/B7-H5/PD-1H Antibody. In a functional ELISA, Recombinant Human VISTA/B7-H5/PD-1H Fc Chimera (Catalog # 7126-B7) binds to immobilized Recombinant Human VSIG3 Fc Chimera (Catalog # 9229-VS) coated at 2 µg/mL (100 µL/well) in a dose-dependent manner (orange line). Binding is blocked (green line) by increasing concentrations of Mouse Anti-Human VISTA/B7-H5/PD-1H Monoclonal Antibody (Catalog # MAB71265). At 25 µg/mL, this antibody will block >90% of the binding.

Vista binding to VSIG3 is blocked by Human VISTA Antibody.


Custom Services

Unable to find an antibody that meets your needs? We offer custom monoclonal antibody panels from our hybridomas. When you order one of our panels you have the ability to screen and select the clone that will fit your specific research.

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We have an existing library of chimeric antigen receptor (CAR) validated single chains, and a validation program for faster development of CARs for your target. Combining this platform and our proprietary hinge designs, we are able to quickly build a CAR panel for testing in your system.

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