Researchers try to wake up immune cells by focusing on the sugars on the tumor surface
NICOLLE RAGER FULLER
Shrink yourself small enough to swoop over the surface of a human cell, and you might be reminded of Earth’s terrain. Fats, or lipids, stay close to the surface, like grasses and shrubs. Proteins stand above the shrubs, as mighty oaks or palm trees. But before you could distinguish the low-lying lipids from the towering proteins, you’d see something else adorning these molecules — sugars.
If proteins are the trees, sugars are the mosses that dangle from the branches or, perhaps, the large fronds of the palm. “The cell surface is basically coated with sugars,” says Carolyn Bertozzi, a chemist at Stanford University. “They’re what viruses, bacteria and other cells see first when they touch down on a target cell.”
The sugars that attach to cell-surface proteins and lipids often take on elaborate structures. Information encoded within these structures helps cells recognize each other and relay messages in virtually every tissue