An Immunoassay Method Based on Chemiluminescence and Magnetic Nanoparticles for Detection of Soluble Programmed Death 1 in Cancer Patients' Serum

摘要

Programmed death 1 (PD-1) is expressed on membrane of activated immune cells, and leads to downregulation of immune response, causing immune suppression through binding programmed death ligand 1 (PD-L1) and PD-L2. It has been indicated that PD-1 and its ligands play an important role in modulating immune system through promotion of apoptosis of antigen-specific T-cells and reducing apoptosis in regulatory T cells (Treg). Recent studies have revealed that PD-1 has a soluble form, and soluble programmed death 1 (sPD-1) increases the complexity and diversity of composition and function of the PD-1/PD-L1 signaling pathway. However, current detection methods for sPD-1 in serum still cannot satisfy the rapid clinical detection that require high sensitivity. Here, we established an immunoassay based on chemiluminescence and magnetic nanoparticles for detecting sPD-1 level in serum of cancer patients with high sensitivity, and also evaluated the physiological and pathological significance of sPD-1 level in patients' serum.