Autologous Thymic Organoids Restrain Melanoma

Melanoma can evade immune attack, so researchers asked whether a patient-derived synthetic thymus could train immune cells to restrain a matched tumour. They reprogrammed blood cells into stem cells, made thymic organoids with thymic epithelial cells, which train T cells, cancer-targeting immune cells, and implanted them in mice with human immune cells and matched melanoma grafts. Across 27 tumours in nine organoid-treated mice versus 30 in 10 controls, tumour burden and growth fell; progression-free survival increased. Staining found more T cells in the viable tumour rim and capsule beside a necrotic centre. This links a patient-matched thymic niche to T cells and melanoma restraint in vivo.