The brain's 'support cells' turn out to have specialists — and a tag called CD51 gives them away

Astrocytes were long treated as the brain's uniform support crew. Using new genetic tools, researchers have shown they actually split into distinct subtypes with a division of labour — including a group marked by a protein called CD51. The work, published in Nature, finally gives scientists a way to tell these cells apart, a step toward understanding what each kind does in health and in disease.