PD1-CD28 fusion protein

The **PD1-CD28 fusion protein** is a synthetic recombinant immune-modulating protein that combines the extracellular and transmembrane domains of the programmed death receptor-1 (PD-1) with the intracellular signaling domain of the costimulatory receptor CD28. This fusion protein is designed to reprogram the immune checkpoint signaling in T cells, converting the inhibitory signal delivered upon PD-1 ligation by its ligand PD-L1 into a stimulatory, CD28-mediated co-stimulatory signal. CD4+ or CD8+ T cells are genetically engineered (typically via retroviral transduction) to express this fusion receptor, enabling them to resist PD-1/PD-L1-mediated immunosuppression in the tumor microenvironment and promote robust cytokine release, proliferation, and anti-tumor cytotoxicity. This approach has primarily been developed for enhancing adoptive T cell therapies, including CAR-T and TCR-modified therapies, showing efficacy in preclinical models of pancreatic cancer, non-Hodgkin lymphoma, and other PD-L1-expressing tumors[1][2][4][5][6][7][9][10].

Other names

PD-1-CD28 chimeric switch receptorPD1-CD28 chimeric switch receptorPD 1-CD28 chimeric switch receptorimmunomodulatory fusion protein (IFP)PD1-CD28 IFPPD-1-CD28 IFPPD 1-CD28 IFP