<unk> is produced at high levels in tumor-infiltrating lymphocytes, such as myeloid-derived suppressor cells and regulatory T cells, and its blockade with an antibody results in delayed tumor growth in mouse models of melanoma and squamous cell carcinoma. Monocytes from HIV-infected patients produce higher levels of<unk> compared to uninfected individuals. The increased<unk> levels correlated with an increase in immune activation and a decrease in CD4-positive T cells. As a drug target There is an ongoing cancer immunotherapy clinical trial for a monoclonal antibody targeting<unk> in advanced cancer. Preliminary results of the phase I clinical trial show good safety tolerance and anti-cancer activity in patients with advanced tumours. Another ongoing clinical trial involves a small molecule that antagonizes the programmed death-ligands 1 and 2 (PD-L1 and PD-L2), and<unk> pathways in patients with advanced solid tumors or lymphomas.
VISTA 
FAST 
KAVA
TOFI
SCoRS
STAR*D
COCIR
CAPOX