New insights: that's why tattoos don't fade
Around 15 percent of Germans have a tattoo. Some people wish they didn't have it, but the tattoo remains - even though the skin is constantly renewed. Researchers have now found out why tattoos don't fade.
Tattoos don't go away despite skin renewal
In the past, tattoos were socially outlawed and reserved for special population groups (e.g. seafarers, prison inmates), but today they are widely accepted and can be found in all social classes. Some want to get rid of the pictures or lettering on the skin. It's just a shame that the tattoos don't just go away, not even though the skin is constantly renewed. Researchers have now found out why the colors are preserved.
Remove old youth sins
Sometimes it is a small rose on the arm, sometimes a dolphin on the back; But it can also be the name of the ex or an ugly "ass antler": Many people have had a tattoo that they want to get rid of.
But what options are there to have the body images removed?
Laser removal is sometimes associated with major health risks. Nevertheless, it is considered the safest and most effective method.
But why is it so problematic to remove tattoos? After all, the skin is constantly renewing itself. Researchers from France have now found an answer to this.
Color particles are deposited in macrophages
When tattooing, water-insoluble color pigments are pricked into the skin. In the past, it was assumed that the tattoo would be preserved permanently because the ink stained connective tissue cells.
However, French scientists have now been able to show in mice that the color particles are deposited in phagocytes - so-called macrophages.
When these cells die, the pigments are initially released, but only until they are taken up again by new macrophages.
As the researchers from Aix Marseille Université report in the journal "Experimental Medicine", the particles largely remain in their original position during this process, so that the tattoo does not change noticeably.
Tails of mice tattooed
To get their results, the researchers tattooed the tails of mice. The animals were genetically modified so that the skin macrophages could be deliberately destroyed by the administration of a toxin.
The scientists examined sections of the tattooed skin under a microscope to confirm that the ink particles were actually absorbed by the macrophages.
Afterwards, they infected the rodents with diphtheria, which resulted in macrophages being destroyed. A few weeks later, new macrophages that had migrated from the blood had replaced the destroyed cells. The tattoo remained unchanged.
Better tattoo removal
"The fact that macrophages hardly move in the skin explains why the tattoo is quite stable," said study author Sandrine Henri, according to a report by the scientific journal "Scientific American".
“In addition, the pigment particles present in the tattoo ink are quite large and, due to their size, do not flow into the lymph nodes via the lymphatic vessels. As soon as they are released by dying macrophages, they get stuck until they are taken up by other macrophages, ”says the researcher.
Simon Yona, an immunologist at University College London who examined macrophages and was not involved in the study, praised the work of the French scientists.
It "actually offers a strategy to remove unwanted tattoos, in combination with conventional approaches that could be particularly useful for removing small tattoos in a well-defined location."
Henri said that she and her colleagues are already developing a method to provide certain types of immune cells with genetic instructions, and are planning to work closely with dermatologists in the next stages of their work.
She hopes that laser tattoo removal could work better when combined with the temporary inhibition of skin-macrophage function. (ad)