Modern tattoo culture has long ceased to be solely a matter of aesthetics or self-expression, becoming an object of close attention from fundamental science. While artists hone their realism techniques and clients choose designs, scientists are trying to understand how the presence of foreign pigment in the dermis affects the complex mechanisms of our immune system over the years. This week, the professional community was stirred by the results of a recent study conducted by specialists from the Institute of Biomedical Sciences (USI) in Switzerland. Experts have found that the usual process of wearing a tattoo creates a specific biological background in the body that can directly correct the effectiveness of modern vaccines, including those against COVID-19.