What’s happening under the skin when a cyst forms?

What’s happening under the skin when a cyst forms?

Marianne De Brito

These images show a rare type of skin cyst called a steatocystoma. From the top layer of the skin, the epidermis, a finger-like stalk leads down into a round cyst within the deeper dermis. At the base are large, pale cells called sebocytes, which normally make the oils that protect our skin and hair. Here, instead of releasing oil onto the skin surface, the sebocytes are filling the cyst from the inside. These cells can be studied using fluorescent staining and gene sequencing.