Freezing tumor-sample TILs for improved efficiencyTo mitigate the toxicity associated with IL-2 therapy, alternative strategies have been explored.One such approach involves using mesenchymal stem cells (MSCs) as a vehicle for targeted delivery of IL-2 to reduce systemic toxicity [68]Genetically engineered IL-2 variants have been developed to potentially reduce systemic toxicity while maintaining efficacy in immunotherapy for solid tumors. This evidence concerns the gene IL2 and neoplasm.