Intratumoral Regulatory T-Cell Ablation Mediates Tumor Control Systemically Without Autoimmunity

Investigators used intratumoral delivery (IT) of diphtheria toxin in Foxp3DTR mice to deplete Tregs within tumor tissues while leaving peripheral Tregs intact. Mechanistically, IT Tregs suppressed antitumor T cell responses by blocking the acquisition and presentation of tumor antigen by conventional type II dendritic cells.