A Tumor-Specific Pro-IL-12 Activates Preexisting Cytotoxic T Cells to Control Established Tumors

Researchers developed a tumor-conditional interleukin-12 (pro-IL-12), which masked IL-12 with selective extracellular receptor–binding domains of the IL-12 receptor while preferentially and persistently activating tumor-infiltrating lymphocytes after being unmasked by matrix metalloproteinases expressed by tumors.