Immune System

 Who does your immune system work?

Your immune system is a crucial part of your body and without it you would be dead, or sick for your whole life. It is what fights bacteria and sickness in your body; it also recognizes bacteria so it will know what to do. Your immune system is built up with 22 different cells all with different jobs but today I will just be focusing on a main six. Now this is how your immune system works.

Firstly bacteria is always around you and your skin waiting for an opening. Say when you cut yourself, bacteria finds the opening and immediately floods in, penetrating the skin and starts to multiply.They first go unnoticed but once they reach a certain amount your immune system starts to notice.

Secondly as bacteria starts to seep into your body, starting to multiply,and overtaking it Macrophages(guard cells) will be the first at the site. Thousands of them will start to eat bacteria, trap it inside their membrane, and suffocate it with enzymes until it is dead. They are your biggest cells being 21 micrometers long and wide. Macrophages also cause inflammation(slight swelling) by sending protein messengers to the blood vessels to let water into the site of bacteria. This makes it easier to kill them. Also when they get tired they send out more messenger proteins to communicate their location and urgency for backup.

Then, Neutrophils hear the Macrophages message, and quickly leave the blood to go help. A Neutrophil's sole purpose is to kill, in fact they fight so furiously they kill healthy cells in the process. They also create sticky barriers that trap and kill bacteria easily. They are so deadly they commit suicide after five days as to not cause the body to much damage.

 Next, when the battle gets too much the brain of the immune system kicks in these are called Dendritic cells. They start to collect samples from bacteria and place pieces of them on their outer layer. They then decide to call in an army of bacteria cells to eradicate the virus, to do this they must travel to the closest Lymph Node(which takes around a day) to activate an army of Killer T cells.

Once the Dendritic cells make their ways to the Lymph Node, T cells are waiting and ready to be activated. When T cells are born they go through difficult and complex training to make sure there is only the best of them left. It is so difficult only a quarter of them survive. When they have completed training they are rewarded with a specific set up skills. Dendritic cells start to look for a Helper T cell whose setup is just right. They are looking for one that they can combine their samples with. T cells are called Virgin Helper T cells when they have no job or samples, and they are called Helper T cells when they do have a job/samples. When the Dendritic finds a T cell with the set up they are looking for a chain reaction begins. The Helper T cell is activated and it quickly duplicates thousands of times. Some become Memory T cells that stay in the Lymph node and will make you practically immune from the certain bacteria. Most will go to the battlefield to fight the bacteria, and the remaining will travel to the centre of the Lymph Node to activate the B cells.

B cells also known as B Lymphocytes are a form of white blood. Virgin B cells are born with a specific setup as well, and are one of the hardest working cells. When a B cell and T cell with the same setup meet, the B cell immediately produces millions of Antibodies. They work so hard literally from exhaustion, thankfully helper T cells stimulate them to keep going even though this does last forever. This also ensures that they will eventually die so the body does not waste energy and hurt itself.

Antibodies are little proteins that are engineered to bind to the surface of a specific intruder. There are different kinds of Antibodies that do different jobs. The helper T cells tell the B cells what type is needed. Then all of them saturate the blood and the body. Then when everything is getting dire at the spot of bacteria, billions of Antibodies flood the bacteria and quickly disable them, rendering them helpless. They also kill and stun them making them an easier target. Antibodies backs are built to connect to Killer Cells so they can join and kill the enemy even quicker.

Then with a team the bacteria is wiped out. At this point millions of body cells have already died, although this is no big deal, as the losses are replenished. Most of your immune cells are now useless and without constant signal they commit suicide, so as to not waste resouraces. Some stay behind, Memory Helper T cells and Memory B cells. So if the bacteria ever comes back in your body, they can wipe it out without you even noticing. And that is how your immune system works.