The Hidden Biology Behind Tattoos and Your Immune System Response

I saw my cousin yesterday, and he just got a new tattoo. Personally, I do not like tattoo because I do not like to get involved in fashion style that leave permanent marks on my body because I know that fashion is continuous and soon, that fashion that looks like the best would go out of vogue. This said, my cousin likes the tattoo and was flaunting it everywhere and showing it directly or indirectly to anyone that could see. That said, I will be discussing about that tattoo you have on your body.

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Before talking about tattoo, let's talk about the skin. The skin is the largest organ in the body, and it is responsible for saving us from a lot of mess either directly or indirectly. The skin is one organ that has direct contact with the world around us, including dirts, insects, vermin, and even microbes but still prevents them from getting access into the body itself. This doesn't mean that the skin doesn't get damaged on a regular, but then the skin finds a way to solve this since the epidermis is usually made of dead cells. After the epidermis is the dermis which is made up of living cells and the epidermis is 1 millimeter deep.

Below the epidermis, stem cells constantly clone themselves to become skin cells. These cells are basal cells, keratinocytes, and so on which each new cells pushing the older cells upward to produce lamellar bodies which create fats which is a waterproof coat that closes gaps within each of them. These cells later die and begin to dry as they are pushed upwards. The epidermis of the skin is made up of about 50 layer of dead skin with over 200 million dead cells hourly.

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That said, tattoos cannot stay on the epidermis because this would be washed off over time. Below the epidermis is the dermis which is made up of tiny blood vessels, sensory cells, roots of hairs, sweat glands that regulates temperature, and immune cells. The dermis of the skin is where the tattoo stays. When tattoos are done, the pins go in very fast, as fast as twice a second, damaging and killing cells. While a lot of tattoo pins are disinfected for those who use reputable tattoo artist, there is still a possibility that some organisms find their way into the skin. This destruction of cells by the needles causes macrophages in the dermis to be triggered after which they rush to the site of the wound, start to kill bacteria, release chemicals, and cause the dermis to swell with fluid as a result of causing the blood vessels to open up.

Tattoo inks are made up of chemicals which can include Nickel, Chromium, and Lead. This chemicals can be carcinogenic and when they get into the body the macrophages identify them as foreign and begin to attack them. They engulf the ink by the mycrophage, and the fibroblasts also try to attack the ink but since it is non-living, it is difficult to destroy. Since the ink cannot the be destroyed, the macrophages stay around the region engulfing as many inks as possible so as to keep it from spreading and to keep you alive.

While the body is doing this to keep you alive, all you see is that beautiful tattoo, although that is not all, you feel hurt, irritated, and you see your skin swollen a little but over time all this is gone as you heal up and you look okay. ALthough you have a pretty shinny tattoo now, over time, dead cells will be removed, and the tattoo will become less vibrant as it was when you first had it. One question you would ask is why does the tattoo not leave when skin cells die off? The answer remains your macrophages. The macrophages hold the ink where they are after engulfing and camping them since they cannot destroy them. So when your skin keeps replacing skin cells, your tattoo doesn't wipe out along with them.

Overtime, macrophages die, and some other ones come to replace them but at this time, tiny ink escape and are caught at different location in the vessels and this is why you would realize that some tattoo begin to fade off gradually overtime.

Tattoos are more than just aesthetic symbols; they are a complex interplay of art and biology. While the visual appeal is immediate and striking, the underlying biological processes are intricate and fascinating. They demonstrate the body's remarkable ability to adapt to and encapsulate foreign substances, a testament to the dynamic and resilient nature of our skin. So, while fashion trends may come and go, the science behind tattoos reveals a deeper, more enduring narrative of human expression and biological wonder.

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Reference

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