BD Article Heena

Overview

What is the immune system?

Your immune system is a large network of organs, white blood cells, proteins and chemicals. These parts all work together to protect you from germs and other invaders. Your immune system also helps your body heal from infections and injuries.

Function

What does the immune system do

Your immune system works hard to keep you healthy. It does this by:

• Keeping invaders (like germs) out of your body.
• Destroying invaders.
• Limiting how much harm the invaders can do if they’re inside your body.
• Healing damage to your body.
• Adapting to new challenges and threats.

Invaders your immune system protects you against include:

• Bacteria.
• Viruses.
• Fungi that can cause infections.
• Parasites.
• Cancer cells.

How does the immune system work?

When your immune system is working properly, it:

• Tells the difference between cells that are yours and those that don’t belong in your body.
• Activates and mobilizes to kill germs that may harm you.
• Ends an attack once the threat is gone.
• Learns about germs after you’ve had contact with them and develops antibodies against them.
• Sends out antibodies to destroy germs that try to enter your body in the future.

But things don’t always go this smoothly. Sometimes, your immune system doesn’t work properly. For example, it may be too weak to fight off invaders, or it may launch too strong of a response.