Are we immune against every Disease?

Jay Kakade
Immune Cells
Illustration of Immune Cells. (Image Credit: Shutterstock)

It will be not wrong to compare ourselves with a planet. We can say we are the living planet made up of more than 40 trillions of cells. In comparison, if our cells were human sized we would be as big as 20 mount Everests.

Same as ozone layer protects Earth from ultraviolet radiations, our immune system protects us from harmful bacteria and viruses. But this external living things has a huge advantage of fast multiplication.

Bacterium is free living organism which consists of a single cell. It can make a full grown copy of its in just an hour. While the virus can make hundreds of copies within an hour and billions in a day.

But human cells take way long time than this to multiply. Mitosis takes 24 hours and Meiosis take about 64 days.

Our immune system applies selective pressure to get rid of these intruders. As they reproduce at tremendous amounts, there are pure chances that an individual adapts itself in a right way to evade immune system and multiply quickly again.

Humans are way too slow to keep up with their evolution. Fortunately, our immune system is one of the most amazing things ever seen by scientists. It is said it is the second most beautiful creation of nature after human brain.

Immune system is so complex and sophisticated that even humans are not able reveal its all secrets.

Why haven't we been killed by new Virus or Bacteria?

Simple way to answer this question is we have two immune systems. One Innate and other Adaptive.

Innate immune system was ready when we were born. It consists of neutrophils, macrophage, complement and dendritic cells.

Adaptive immune system contains T-cells and B-cells which are very effective and efficient to intruders organisms like virus or bacteria.

These cells are very complex and takes time in formation. But, once they are ready they make a real protection for a body.

What makes our immune system so strong is the immense storage of antibodies. It has answer to almost every disease including Black Death, Coronavirus or other virus that will emerge in upcoming future.

This ability allows us to control the rate of reproduction of virus or bacteria.

how is it even possible?

To understand it we must understand something else. Almost all the animals on Earth are made up of some basic elements. This basic elements can be proteins.

Immune cells
Illustration of Immune cells with receptors. (Image credit: KATERYNA KON/SCIENCE PHOTO LIBRARY via Getty)

Proteins are building blocks of life. Proteins can have billions of different shapes that exists. It is due to these shapes that viruses or bacteria have different structures.

Why protein is important?

Basically, proteins are a type of communication between microworld. Cells don't have eyes or ears to recognise friend or enemy. Therefore they need to touch each other to recognise so.

Recognising here means that cells have countless number of receptors. This receptors connects with proteins and marks them a part of our body or an external foe.

When this receptors connects with enemy proteins, it marks it as enemy and attacks it. Only if our immune system is able to distinguish between friend and foe, it is able to protect us from invader.

As there are billions of shapes to proteins, they can be billions of shapes of viruses and bacteria. This is a reason why we face a new strain of corona virus each year. Coronavirus mutates very fast and changes its shape of proteins to evade immune system.

Our adaptive immune system is a weapon to fight such invaders as they have all protein shapes memorized when attacked. But still our immune system is ineffective against billions of mutations that takes place.

Adaptive immune system is able to distinguish between billions of protein puzzle shapes. And it is the reason why we are alive. This memorized shapes are enough to fight against enemies.

How can our immune system memorise billions of structure?

When enemy protein structure is recognised by receptors it captures cheat code of intruder and mixes it with own genetic code and turns receptors more powerful.

We can say that the adaptive immune system mixes own genetic code with tiny part of intruder and create billions of different shapes for receptors.

So this mixture ends creation of 10 billions combinations and unique immune cells with different receptors. So we end up with one unique receptor for every possible enemy exists.


Post a Comment

* Please Don't Spam Here. All the Comments are Reviewed by Admin.
Post a Comment (0)
To Top