Edge-Guard Macrophages Attack Live Melanoma Cells, Poised to Boost Immunotherapy

Researchers using real-time imaging show CD169-positive macrophages at the edges of melanoma tumors actively engulf live cancer cells and help signal the immune system, constraining tumor growth even without T cells or B cells. Similar macrophages are found in human samples, suggesting these cells could be mobilized to convert cold tumors to hot and broaden the reach of immunotherapies like checkpoint inhibitors.