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Tattoo pigment can outlast the cells that hold it

In a study using green pigment in mouse skin, researchers found evidence of release and recapture by dermal macrophages. The model offers a reason lasting color need not mean a single cell lasts as long as the tattoo.

4–6 min

Questions you could explore

  • What evidence in the mouse study showed pigment being released and recaptured as macrophages turned over?
  • What would need checking before extending this persistence mechanism to different human tattoo inks?

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