Progenitors of Glia

What am I looking at?

This image is a culture of human neural progenitor cells and fully differentiated astrocytes. The progenitor cells are green (1) and the adult astrocytes are gold/orange (2); the astrocytes have differentiated from the progenitor cells. The nuclei of all the cells are purple/blue (3).

Biology in the background

During development, and to some extent during adulthood, stem cells can turn into many different cell types. This is a multistep process involving a variety of different molecular signals and developmental stages. One of these stages occurs when a stem cell has partially differentiated. At this stage, the cells are known as progenitor cells.

This image shows a culture of neural progenitor cells (1) that have been directed (by the researchers) to become a kind of glia – a support cell of the nervous system – called an astrocyte (2). Astrocytes are star-shaped cells (hence their name – astro is the Greek word for “star”) that support the proper function of neurons in the brain. They fulfill a wide variety of roles, including promoting synapse formation, removing excess neurotransmitters from synapses, and maintaining and regulating the blood-brain barrier.

In humans, neural progenitor cells are classified as small if their cell body is between 5 and 10 micrometers across, or roughly seven to 10 times smaller than the width of a human hair, or large if their cell body is between 10 and 15 micrometers across, or roughly five to 10 times smaller than the width of a human hair. Astrocytes have cell bodies that are between 10 and 20 micrometers across, or roughly four to seven times smaller than the width of a human hair.

Technique  

This image was created using confocal microscopy.