VITILIGO
occurs when the immune system mistakes melanocytes — cells that are produced in the hair follicles and give skin and hair color — as threatening.
Back
In response, it signals immune cells called CD8 T-cells to sneak into the skin, where they release cytokines (proteins that cause inflammation),
hunt down melanocytes,
and destroy them.
The loss of melanocytes causes the patches of pigmentless skin that characterize vitiligo.
JAK inhibitors interrupt the search-and-destroy signals sent out by the immune system.
The hair follicles where aren’t affected by
melanocytes form the immune system.
Replay
So once a JAK inhibitor blocks the immune system signal, newly-formed melanocytes can migrate to areas affected by vitiligo and bring color back to the skin.
