BioSim™ anti-Durvalumab (Human) ELISA Kit

Durvalumab is a human IgG1 monoclonal antibody that binds to and inhibits programmed cell death ligand 1 (PD-L1). PD-L1 is an important immune checkpoint molecule expressed on tumor cells and tumor-infiltrating immune cells. PD-L1 binds to its receptors PD-1 and B7.1 located on the surface of activated T cells and antigen-presenting cells and in turn suppresses cytotoxic T-cell activity, the proliferation of T-cells, and production of cytokines. The monoclonal antibody binds to PD-L1 and inhibits its anti-tumor immune response, and thus reduces tumor growth without causing antibody-dependent cellular cytotoxicity. The original antibody is approved to treat locally advanced or metastatic urothelial carcinoma and locally advanced unresectable non-small cell lung cancer (NSCLC). However, upon administration of the antibody, patients tend to develop an immune response that results in the formation of anti-Durvalumab antibodies, thus adversely affecting the therapeutic response to treatment. BioSim™ anti-Durvalumab ELISA kit qualitatively measures antibodies to Durvalumab in human serum or plasma samples. The kit is based on the Sandwich ELISA principle. Standards and samples (serum or plasma) are added to the microtiter plate coated with Durvalumab. After incubation, the wells are washed. The HRP conjugated probe is added and binds to the antibodies to Durvalumab that is captured by Durvalumab coated on the wells. Following incubation, wells are washed and the enzymatic activity is detected by the addition of TMB chromogen substrate. Finally, the reaction is terminated with an acidic stop solution. The color developed is proportional to the amount of antibodies to Durvalumab in the sample or standard. The qualitative test results can be evaluated using cut-off values.