Evaluation of LIGHT-derived peptides to disrupt the HVEM/LIGHT immune checkpoint.

Immune checkpoints are critical regulators of immune homeostasis and have become prominent targets in the treatment of various malignancies and autoimmune disorders. While monoclonal antibodies currently dominate checkpoint-targeted therapies, there is a growing interest in alternative approaches, which may offer advantages including smaller size, greater specificity, ease of manufacturing, or a reduced risk of immune-related adverse events. In this study, we focused on the HVEM and its ligand LIGHT, a receptor-ligand pair involved in modulating T cell responses. Overstimulation of HVEM/LIGHT pathway is associated with the pathogenesis of autoimmune diseases and can lead to graft rejection. Therefore, targeting this interaction may offer novel therapeutic strategies for inducing immunosuppression and preventing graft rejection. Utilizing computational approaches, we designed a series of LIGHT-derived peptides. Various simulation techniques, such as molecular dynamics with MMGBSA analyses (with and without NMA), work associated with conformal change and SMD were employed to predict their binding affinities to HVEM. Selected peptides were synthesized and subjected to experimental validation to assess their binding capabilities to HVEM, determined using the spectral shift technique, and inhibitory effects on the HVEM/LIGHT complex formation, evaluated through immunoenzymatic assays and cellular studies. Among these, two peptides demonstrated inhibitory potential, suggesting that they might have utility as scaffold for further optimization. These findings underscore the potential of peptide-based inhibitors in modulating immune checkpoints and pave the way for novel immunotherapeutic strategies.