Since childhood, we are given booster shots to make us immune to certain diseases such as tetanus, polio, etc. In 2020, we have seen the entire globe worry about immunity and seek various measures to strengthen it. We have seen how the vaccination campaign in India was carried out to ensure antibodies against the Covid-19 virus entered people's immune systems and protected them against the disease.
What Exactly is Immunity?
Immunity is the body's defence mechanism or system against problematic infections and diseases. Each day when we step out, we come into contact with many invisible pathogens. Look at how we wear masks to protect ourselves from Covid-19! The body's inbuilt mechanism that protects us from being harmed by these pathogens is the immune system or the power of immunity. It does this by producing antibodies that can fight off bacteria and pathogens. The immune system can thus be called a dynamic system that strives to keep us healthy and glowing.
What is Innate Immunity?
Innate immunity is the body's built-in capacity to combat pathogens and destroy dead or malfunctioning cells. This system contains organs, cells, tissues and various proteins. It is kind of a natural defence system within us, protecting us from harmful elements right from the moment we enter this world.
What is Adaptive Immunity?
As we grow up into teenagers and adults, our body acquires a form of immunity which is not present since birth. This is adaptive immunity, where the body is able to adapt and recover even if particular pathogens do enter.
Let us look at the difference between adaptive and innate immunity.
Innate immunity is the body's natural defence system present since birth.
Adaptive immunity is acquired as we grow through the various stages of life.
The innate immune system is not antigen-specific but rather acts as soon as an antigen enters the body.
The adaptive immunity is antigen-specific. This response is created after the first time that the body comes into contact with the antigen.
Remember how we have the first and second line of defence in our army?
Similarly, innate immunity is the primary line of defence that is activated as soon as antigens come in contact with the body.
Adaptive immunity falls in the second line of defence once the antigen or pathogen has crossed the first barrier of innate immunity.
Innate immunity is present in the body right from birth.
However, adaptive immunity is an essential form of immunity that is acquired as we grow up and battle various antigens.
Innate immunity is not formed based on the presence or absence of its substrate, hence it is not inducible.
However, adaptive immunity is inductive.
Innate immunity is non-specific while adaptive immunity is specific in nature.
The Cells and Molecules Involved
Mast cells, dendritic cells, phagocytic leukocytes and natural killer cells are cells of the built-in immune system while interferon, acute-phase proteins, cytokines and complements are its molecules.
Adaptive immunity has Killer CD8+ T-cells, Helper CD4+ T-cells, B-cells for its cells and its molecules are cytokines and antibodies.
What are the Components?
Skin, mucous membranes, epithelial cells and phagocytes are the components of innate immunity.
Adaptive immunity consists of lymphoma organs that can produce T cells and B cells that have specialised abilities to fight antigens.
What do they fight against?
While innate immunity is able to fight any pathogens entering the body, adaptive immunity can fight only against specific infections.
The Immunological Memory
Innate immunity does not have any mechanism to keep the memory of pathogens but adaptive immunity has memory cells that can keep the memory of pathogens and antigens.
Adaptive immunity has greater potency and effectiveness than innate immunity.
The response time for innate immunity is almost immediate while it is slower for adaptive immunity.
Innate immunity is inherited from parents while that is not the case for adaptive immunity.