New study by Czech researchers: Tattoos may affect immune system
Getting a tattoo may leave a lasting mark not only on your skin, but also on your immune system. This is the conclusion of a groundbreaking international study involving researchers from the Biology Centre of the Czech Academy of Sciences. The research shows that commonly used tattoo pigments can influence immune function, trigger inflammation and even alter the effectiveness of certain vaccines.
Immediately after a tattoo is applied, pigment particles do not remain confined to the skin. Instead, they spread rapidly through the lymphatic system and accumulate in lymph nodes – key sites for proper immune function – where they can persist for years. Although concerns about the chemical safety of tattoo inks have been raised in the past, their long-term effects on the immune system were largely unknown. This study, originally published in the prestigious US scientific journal PNAS (https://www.pnas.org/doi/10.1073/pnas.2510392122), set out to address that gap.
Martin Palus, one of the Czech researchers involved, explained how tattoo ink interacts with immune cells:
“We focused on red, black and green inks that are approved for use on the European market. Within a few hours, the ink travels to the lymph nodes, where it ends up alongside immune cells known as macrophages. Unfortunately, these cells are unable to process tattoo ink in the same way they deal with biological material such as viruses or bacteria.”
As a result, the affected immune cells are damaged and eventually destroyed – an effect most pronounced with black and red inks. According to Palus, tattooing triggers a two-phase inflammatory response.
“There is an acute phase lasting around two days after tattooing, followed by a chronic phase. During this chronic phase, immune cells are unable to break down the ink. Cell death occurs and the process repeats, which can have a long-term impact on our immune defences.”
The Czech biologist also warns that chronic inf, /l l/lammation caused by tattooing may be linked to other health conditions.
“Persistent inflammation may influence the development of diseases such as cancer, autoimmune disorders or the course of infections.”
To reach these conclusions, researchers isolated immune cells from human blood samples and exposed them to tattoo ink under laboratory conditions. The cells were then also exposed to various vaccines to assess whether tattoos affected vaccine responses, as Palus explained:
“We set out to answer a question that emerged during the COVID-19 pandemic: whether a vaccine administered into a tattooed arm is as effective. Our findings were confirmed when we observed lower antibody production in tattooed mice after receiving a vaccine against COVID-19. At the same time, we confirmed these results in human immune cells that had been exposed to tattoo pigment and showed a reduced response to the vaccine.”
Further research on this topic is expected in the coming years. In the meantime, the current study – which brought together twelve international research teams – underscores the need to examine both the safety of tattoo inks and the long-term effects of their presence in the body. Despite the growing popularity of tattoos, these inks remain subject to far less stringent regulation than pharmaceuticals or other products intended for use in the human body.
