PD-1:CD28 chimeric costimulatory switch protein

PD-1:CD28 chimeric costimulatory switch protein (CSP), also referred to as a chimeric switch receptor (CSR), is an engineered fusion protein designed to enhance the efficacy of adoptive T-cell therapies (such as CAR-T or TCR-T cells) in solid tumors. It consists of the extracellular domain of the programmed cell death protein 1 (PD-1) receptor fused to the transmembrane and intracellular signaling domains of the CD28 costimulatory molecule. In the immunosuppressive tumor microenvironment, tumor cells often express PD-L1, which binds to PD-1 on T cells to transmit inhibitory signals and induce T-cell exhaustion. The PD-1:CD28 CSP intercepts this inhibitory PD-1/PD-L1 interaction and converts it into a positive, activating costimulatory signal via the CD28 pathway. This molecular switch enhances T-cell proliferation, cytokine production, metabolic fitness, and sustained cytotoxic activity against PD-L1-positive tumor cells.

Other names

PD-1-CD28 chimeric costimulatory switch proteinPD1-CD28 chimeric costimulatory switch proteinPD 1-CD28 chimeric costimulatory switch proteinPD-1-CD28 fusion proteinPD1-CD28 fusion proteinPD 1-CD28 fusion proteinPD-1-CD28 switch receptorPD1-CD28 switch receptorPD 1-CD28 switch receptorPD-1/CD28 chimeric costimulatory switch proteinPD-1/CD28 chimeric switch receptorPD-1/CD28 chimeric switch-receptorPD-1:28 CSPPD-1:CD28 chimeric costimulatory receptorPD-1:CD28 chimeric switch receptorPD-1:CD28 CSP