What is the Immune System

The Function of the Immune System

To understand the technology of CAR-T cells we first need to have a basic understanding at least conceptually of how the human immune system works.

The function of the immune system is to protect the body from agents that are harmful to cells and the body. This is a very broad definition and therefore there are a number of different cells that work together to protect the body from infection from harmful agents (Viruses, Cancer, bacteria, etc.)

Broadly the immune system can be split up into two main parts the innate and the adaptive immune system.

The innate immune system

The Innate Immune system are always there waiting to destroy foreign agents and is often fast action and non-specific.

The adaptive immune system

For viruses and bacteria that are not killed off by the innate immune system, the body has a network of cells that can recognise what these infectious agents look like and initiate a specialised attack against that specific infection. These include B-Cells and T-Cells

B-Cells

B- Cells secrete things called anti-bodies which are a specific shape so that it can attach to the infectious agent like a puzzle piece. and when they latch on to the infectious agent they stop it from being able to do damage to the cells inside the body. There are a number of different types of anti-bodies that all do similar and different things, but the complexity of it is unimportant.

T-Cells

T-Cells do not secrete things to fight infectious agents but rather they have specialised proteins on their surface that, like B-Cells, fit onto a specific antigen. This allows them to attach to their target. Once they are attached onto a target they can destroy it or they can attract B-Cells to them so that anti-bodies are made to attack the infectious agent.

One interest in current research of mine is CAR-T cells so it is important to understand broadly how the immune system works.