PD1-PDL1 inhibitor 2 is a small molecule research chemical used in the field of immunotherapy, particularly for studying cancer treatment mechanisms. It works by blocking the interaction between PD-1 and PD-L1 proteins, which are involved in suppressing the immune response. By inhibiting this pathway, it helps to enhance the immune system's ability to recognize and attack cancer cells in experimental models. This makes it a valuable tool for research on various types of cancers, including melanoma, non-small cell lung cancer, and renal cell carcinoma. It is often used in combination with other agents in preclinical studies to evaluate efficacy and potential therapeutic outcomes. Note: This is a research reagent and not an approved therapeutic drug.