Research is being conducted on the interactions between PD-1 and its ligands, PD-L1 and PD-L2, with a focus on the effects of redox on these interactions. The study of these interactions is part of a broader effort to understand and develop cancer immunotherapies, with various outlets reporting on different aspects of this field. The specific findings and implications of the research on PD-1/PD-L1 and PD-1/PD-L2 interactions are not clear from the available information.