Mouse study reveals that tattoo ink migrates into the lymphatic system altering the immune response
Research shows how pigments from tattoos reach the lymph nodes, causing persistent inflammation and altering the efficacy of vaccines such as anti-Covid and flu vaccines.
Key points
The ink from tattoos does not remain on the skin but is absorbed by the body, affecting the immune system. This is shown by a study published in Pnas (Proceedings of the National Academy of Sciences) and conducted by researchers from the University of Southern Switzerland, in collaboration with the University of Bern, Regensburg University Hospital, the Biology Centre of the Czech Academy of Sciences, the International Agency for Cancer Research, the Cantonal Institute of Pathology in Locarno, the Basel Cantonal Laboratory and the Hannover Medical School.
The journey of ink from the skin to other organs
The study sought answers for one of the main concerns related to tattoo safety: the possible redistribution of ink not retained by the tattoo site to organs other than the skin and the consequent toxic effect that the accumulation of these insoluble pigments could have systemically for the body in the medium and long term.
"Despite safety concerns regarding the toxicity of tattoo ink, the authors explain, no study to date has investigated the consequences of tattooing on the immune response. With our work, we characterised the transport and accumulation of different tattoo inks in the lymphatic system, using a mouse model."
With this in mind, the team was able to demonstrate that tattoo ink does not remain inert on the skin. In fact, the research shows that it moves rapidly into the lymphatic system, where it can persist for several months, kill immune system cells and even alter the body's response to vaccines.
Collection in lymph nodes and inflammation
The mouse models used by the scientists showed that, once in contact with the skin, the pigments of the tattoo ink reached the nearby lymph nodes within minutes and accumulated there for two months, inducing immune cell death and a state of inflammation.
