Researchers in France have discovered that, though a tattoo may be forever, the skin cells that carry the tattoo pigment are not. The research, carried out on mice, has shown that the skin cells into which the tattoo is fixed are not fixed themselves, and when they die, those cells can pass the pigment on to new cells. But they don’t just pass them on – they ‘eat’ the tattoo beforehand, thus reducing the amount of ink in the skin over time.
The study, which was published on March 6, 2018 in the Journal of Experimental Medicine, suggests ways to improve the ability of laser surgery to remove unwanted tattoos.
For centuries we have assumed that once tattooed that’s it – the image or words are there for life. Then came tattoo cover-ups, allowing ink that people had grown tired of or grown out of to be covered up with a new design by experienced, talented artists.
Finally, we reached the point where lasers were employed to remove tattoos entirely. The technology works, and it means that those youthful (or not so youthful) indiscretions can be made as invisible as possible. Sometimes, however, it’s not possible to remove all of it. This is especially true of tattoos with a colored pigment.
These special cells are called macrophages and they are immune cells that you can find in the dermis (the true skin that is under the epidermis). It seems that they come swarming towards the site of the tattoo, thinking that it is a wound that needs to be healed (which, to all intents and purposes, it is). It consumes the ‘injured’ cells, thus replicating the tattoo for all eternity because when the macrophages die, they too are swallowed up. The tattoo remains the same, but the skin beneath it is different.
The authors speculate that laser removal on tattoos can become a lot more accurate and the results can be a lot more impressive. Why? Because the laser can target the macrophages specifically, meaning that, over time, the tattoo will fade entirely because there will be fewer and fewer pigments to swallow up.
About the Journal of Experimental Medicine
The Journal of Experimental Medicine (JEM) features peer-reviewed research on immunology, cancer biology, stem cell biology, microbial pathogenesis, vascular biology, and neurobiology. All editorial decisions are made by research-active scientists in conjunction with in-house scientific editors. JEM provides free online access to many article types from the date of publication and to all archival content. Established in 1896, JEM is published by Rockefeller University Press. For more information, visit jem.org.