The study reports the successful transfer of genetically engineered lymphocytes to patients with metastatic melanoma, achieving durable engraftment and tumor regression. The researchers used a retrovirus to encode a T cell receptor (TCR) specific for tumor-associated antigens (TAAs) such as MART-1, gp100, NY-ESO-1, and p53. These engineered lymphocytes were transduced from peripheral blood lymphocytes (PBLs) and infused into 15 patients. The transduced cells showed high levels of persistence and activity, with two patients experiencing complete or near-complete regression of metastatic melanoma. The study highlights the potential of genetically engineered cells for cancer immunotherapy, particularly in patients who do not have access to tumor-infiltrating lymphocytes (TILs).The study reports the successful transfer of genetically engineered lymphocytes to patients with metastatic melanoma, achieving durable engraftment and tumor regression. The researchers used a retrovirus to encode a T cell receptor (TCR) specific for tumor-associated antigens (TAAs) such as MART-1, gp100, NY-ESO-1, and p53. These engineered lymphocytes were transduced from peripheral blood lymphocytes (PBLs) and infused into 15 patients. The transduced cells showed high levels of persistence and activity, with two patients experiencing complete or near-complete regression of metastatic melanoma. The study highlights the potential of genetically engineered cells for cancer immunotherapy, particularly in patients who do not have access to tumor-infiltrating lymphocytes (TILs).