Researchers Read the Sugary ‘Language’ on Cell Surfaces

Glycans, the complex sugars that stud cellular surfaces, are like a language that life uses to mediate vital interactions

• Researchers are learning how to read their meaning.

• After analyzing a comprehensive data set of glycan structures and their known interactions, researchers at Harvard University and the Massachusetts Institute of Technology found a shared structural language that all organisms use when making glycans.

Abundant but Mysterious

• Hundreds of millions of sialic acid glycans that are present in other primate cells are missing from human ones.

• Glycans were heavily researched through the 1970s and the first half of the 1980s, with one Nobel Prize every decade. There was no corresponding improvement in resources for studying them.

• DNA, RNA and proteins took off and left glycans behind.

Molecular Windows Into Disease

• Researchers have already turned to glycomolecules to gain new insights about conditions as diverse as cystic fibrosis, cancers, sickle cell anemia, HIV and COVID-19.

• Linking that knowledge to new treatments or preventive measures remains a grand challenge.

Decoding the Language of Glycans

• Even closely related species with high levels of genetic similarity, like chimps and humans, have glycans that can vary significantly because of constant, ongoing coevolution.

• Each species faces its own evolutionary pressures from diseases that leave a mark on its library of glycans: The host glycome evolves to evade or counter pathogens' attacks, and the pathogens' glycomes evolve to escape the immune defenses of their potential hosts.