For decades, solid tumors have stood apart from blood cancers as largely beyond the reach of immunotherapy's most celebrated advances — not for lack of ambition, but because the machinery driving these cancers hides inside the cell, invisible to most engineered immune treatments. A team at UCLA has now published a method that reaches inward, using cord blood stem cells to grow precision immune cells capable of recognizing hidden tumor proteins, controlling cancer in animal models without attacking healthy tissue, and doing so at a cost that could bring such therapies within reach of far more p