♦ What are checkpoint proteins ?
Checkpoint Proteins are made of at least 7 ligands and 5 receptors. The redundancy in the interaction specificity between ligands and receptors are reminiscent of the TNF superfamily. For example, B7-1 interacts with both CD28 and CTLA-4, yet these interactions deliver stimulatory and inhibitory signals, respectively. Collectively this family of molecules are called co-stimulatory proteins, yet they deliver both positive and negative signals. In addition, even though the “ligand” proteins have relatively short cytoplasmic tails, it appears they are also capable of deliver the “inward” signaling upon interaction with their respective receptors.
♦ Advantages of checkpoint proteins
· All proteins are affinity purified from the cultured media, size fractionated by SEC column chromatography
· High quanlity and high purity
· Low endotoxin contents (≤ 1.0 EU/mg protein)
· Flexible Fc region formats
♦ Advantages of Fc fusion proteins
· Easy to purify: Proteins with Fc tag can be purified conveniently by protein A/G purification system
· High immunogenicity: Fc fusion proteins are able to induce stronger antibody dependent immune responses compare to those without Fc tag
· Friendly for drug development: Fc fusion proteins can be used in evaluating protein-protein binding affinity based on its Fc tag
· High stability with long half-life
♦ Product list