PD-1 and PD-L1
The immune system is capable of defending against pathogens and early malignant cells, but it maintains tolerance to self. PD-1 and its ligand PD-L1 are surface proteins expressed on activated T cells and APCs respectively. When PD-L1 binds to PD-1, an inhibitory signal is transmitted into T cells and reduces cytokine production and suppresses T-cell proliferation thus protect APCs from killing by T cells. Many cancer cells over-express PD-L1 to escape the immunological attack by inactivating T cells.
Soluble PD-1 (sPD-1)
Soluble PD-1 (sPD-1) is present in patients/animal models with autoimmune diseases and cancer. For example, sPD-1 is detectable in the synovial fluid and sera of patients with rheumatoid arthritis (RA). The serum sPD-1 level may be a potential biomarker for RA as the increased levels correlate with disease activity.
sPD-1 can antagonize the inhibitory effect of membrane-bound PD-L1 and improves the anti-tumor immunity. It is reported that elevated sPD-1 level is associated with prolonged survival in patients with non-small cell lung cancer treated with erlotinib.
sPD-1 ELISA Kit
Blood levels of sPD-1 might facilitate the prediction of pathological characteristics, treatment response, and survival outcomes in patients with autoimmune diseases or cancers.
arigo is proud to introduce our new Mouse PD-1 ELISA Kit (ARG81342). This ELISA Kit has the best sensitivity performance (8 pg/ml) and is suitable for mouse samples of plasma, serum, and cell culture supernatant. It is the excellent solution for preclinical studies or pharmathetical development for autoimmune diseases or cancers in mouse model.
CTLA-4, another coinhibitory receptor, also has a soluble form that is also correlated with autoimmune diseases. CTLA-4 ELISA Kit (ARG81327) is also available in arigo.