Category : Blogs

Sub Category : Science and Technology

" Military action is important the nation, it is the ground of death and life, the path of survival and destruction, so it is imperative to examine it "
Master Sun Tzu said that a long time ago but even before that we had been engaged in a never-ceasing battle with the unseen enemies - Microbes. Believe it or not but you were first engaged in this battle even before you were born and you will keep engaged until you are dead. These creatures are always trying to invade your body. These microorganisms were discovered in 1665 and we have been living for some million years. So how is it that when we were not even aware of their existence, we managed to survive. We managed to survive as we were born with a built-in system of defense - Immune System. It is a gift that God bestowed upon us all.
The concept of Immune system was first discovered in 1665. After numerous researchers now we can safely classify it into two branches
1) Innate Immune System ( Non-Specific )
2) Adaptive Immune System ( Specific )
In this essay we would not be discussing these branches separately as it would take a lot of pages to do so instead we would discuss a simple question ' What happens inside your body when a pathogen enters it '
Imagine it is a nice day. You are taking a walk in nearby woods when suddenly you run into a thorn-bush and hurt yourself. Skin - the first line of defense - is ruptured. Bacteria size this opportunity and enter your body. They start multiplying and damage the body. First to react to this invasion are Macrophages. They swallow up the enemies and break them down through an enzyme called Lysozyme. Meanwhile, they do their secondary job as well, transmitting information to the upcoming army and making the battle easier. When the battle starts getting harder they send for Neutrophiles. Neutrophils leave their patrol route at once and rush to the battlefield. Neutrophils are so intense and devoted to the task that they kill body's healthy cells in the process. That is why they are programmed to commit suicide after 5 days so as to prevent further loss of energy in the body.
But what if the Neutrophiles also prove to be insufficient. Then the Intelligence is called for, The Brain. The brain sends its spies to the battlefield which are called Dendrites. They start collecting samples of antigen, rip them apart and process them. Now they have to make a decision of utmost importance, should they call Antiviral bodies - which eradicate the infected cells - or should they call Antibacterial ones. In this case, they call latter ones. They carry the torn pieces to the lymph node - a factory where Helper T-Cells and Killer T-Cells are produced. Helper T-cells are born with a specific setup for a specific antigen. It's like a specific key to a specific lock. Dendritic cells look for the exact same setup for the antigen that has entered. Once found, helper T-cell starts replicating into thousands. Some of them turn into memory cells, some travel to the battlefield and the rest go to the lymph node to meet with B-cells.
Like T-cell, B-cell is also born with a specific setup & when T-cell finds one with the same setup. B-cell is activated & starts replicating, at the same time it starts producing Antibodies. Antibodies are engineered with a specific system to bind to the surface of the intruder. Problem is that Antibodies are of different types. Helper T-cell tells B-cell which type of Antibody is required for this intruder.
Meanwhile, the situation on the battlefield starts getting worse. Macrophages start getting tired. Here Helper T-cells play yet another role, they order them to fight more. Then the Antibodies arrive at the scene. They stun, disable and kill the microbes & finally the enemy is wiped out. After eradication of the enemy, nearly all the cells commit suicide to prevent further loss of energy but a few remain. These are Memory cells, they store data of this specific intruder. If the same one happens to come back they will get rid of it before you even notice.
Now it was the simplest and briefest possible explanation of Immune System. Imagine how complex our body is.


' Indeed the greatest of Knowledge lies deepest in Nature. '