CD274. also known as programmed death-ligand 1 (PD-L1), is a transmembrane protein belonging to the B7 family of immune checkpoint molecules. It plays a critical role in modulating immune responses by binding to its receptor PD-1 (programmed cell death protein 1) on T cells, thereby suppressing T-cell activation and promoting immune tolerance. Tumors often exploit this pathway by overexpressing PD-L1 to evade immune surveillance, enabling uncontrolled growth and metastasis. Targeting the PD-1/PD-L1 axis has emerged as a groundbreaking strategy in cancer immunotherapy.
CD274 antibodies are monoclonal antibodies designed to block the interaction between PD-L1 and PD-1. effectively "releasing the brakes" on T cells and restoring their anti-tumor activity. Since the first FDA approval of anti-PD-L1 agents like atezolizumab (2016), durvalumab, and avelumab, these therapies have transformed treatment paradigms for various cancers, including non-small cell lung cancer, urothelial carcinoma, and triple-negative breast cancer. Beyond oncology, PD-L1 antibodies are being explored in infectious diseases and autoimmune conditions due to their immunoregulatory properties.
Clinically, CD274 antibodies are often used as monotherapy or combined with chemotherapy, radiation, or other immunotherapies. Their efficacy correlates with tumor PD-L1 expression levels, which are assessed via companion diagnostic assays. However, challenges persist, including variable response rates, acquired resistance, and immune-related adverse events. Ongoing research focuses on optimizing patient selection, identifying predictive biomarkers, and developing next-generation agents with improved safety profiles.