There's a frustrating fact about today's immunotherapies for cancer. While sometimes they work beautifully -; completely eliminating or greatly reducing cancer in particular patients -; other times they don't work at all. It's a mystery.
Scientists have posed several hypotheses to explain the disparity. Perhaps it's the number of mutations present in a tumor, with more mutations leading to better responses. Or maybe it's the tissue environment surrounding the tumor, with some environments supporting and others suppressing effective immune responses.
But so far, none of these explanations has proved definitive or applicable in all cases. Researchers at Memorial Sloan Kettering Cancer Center (MSK) and Baylor College of Medicine in Houston, Texas, now think they have a better explanation. It turns out that in order for immune cells to effectively kill the cells of a tumor, they need to take on a specific spatial configuration.
They need to form a triad." Andrea Schietinger, PhD, a tumor immunologist and member of the Immunology Program in MSK's Sloan Kettering Institute Triad -; meaning three cells. But not just any three cells will do.
What you need, she explains, is three different immune cells all collaborating together at the same time and in the same spot: one dendritic cell, one cytotoxic ("killer") T cell, and one helper T cell. These cells aren't rare or unusual, immunologically speaking. They're the standard actors described in any immunology textbook.
But up until now,.
