Immune System and Tattoos

Introduction

• Tattoos initiate a complex immune response.
• Ink particles are perceived as foreign invaders by the immune system.

Skin Structure and Function

• Largest Organ: Skin is the largest organ and serves as a barrier against external microbes and damage.
• Conveyor Belt of Death:
  • Skin surface is dead cells.
  • Alive skin cells start 1 mm deep, continuously pushed to the surface.
  • Dead cells are interlocked, waterproof, forming a protective barrier.
  • Constant shedding removes dirt and bacteria.

Tattoo Process

• Tattooing: Involves needles penetrating the dermis.
• Damage and Infection Risk:
  • Thousands of cells are destroyed.
  • Potential bacteria introduction.
• Immune Response:
  • Macrophages are activated.
  • Blood vessels dilate increasing fluid in dermis.

Immune System’s Role

• Macrophages:
  • Attempt to engulf ink particles.
  • Ink particles are too large and inert to be broken down.
  • Macrophages engulf and trap ink particles.
• Ink Stability:
  • Ink trapped inside macrophages.
  • Tattoo ink is considered indestructible by macrophages.

Tattoo Longevity and Fading

• Over time, macrophages die and release ink, which is recaptured.
• Tattoo edges may blur as ink moves.
• Some ink can migrate throughout the body.

Tattoo Removal

• Laser Removal:
  • Breaks ink into smaller particles.
  • New macrophages attempt to capture these.
  • Process causes damage to macrophages.

Summary

• Tattoos are a permanent art due to macrophages' role in ink entrapment.
• Caution advised when selecting tattoo designs.

Educational Resource

• Brilliant.org Collaboration:
  • Offers lessons on scientific topics including immune responses.
  • Interactive courses available.
  • Special offer for Kurzgesagt viewers.