HUMAN IMMUNITY MECHANISM

Immunity is our body’s ability to fight the virus and bacteria that are harmful to it. It comes in two ways; inborn and adaptive.

Inborn immunity is the innate ability of the body to quickly jump at protecting it against the intruder. It is a set of ever ready and ever vigilant cells that attack  the intruding pathogen instantly, to kill it, mostly succeeding but failing at times as the intruder may come in large numbers and its intensity, much higher. 

Adaptive immunity is what the body acquires as it goes through the infection. Adaptive immunity comes from two types of white blood cells; T & B.

T cells detect the molecular details of the pathogen and based on it, produce a targeted response on the intruder to kill it. T cells also manage and control the early attack by inborn immunity which is called ‘cytokine storm’. Excessive response of the cytokine storm can destroy the lung tissues, thereby creating acute respiratory distress, leading to short supply of oxygen to internal organs, resulting in multiple organ failure and possibly death. 

B cells produce the antibody, a protein that sticks on viral particle, binding it and  blocking it from entering our cells, thus, stopping the infection on its track. 

Antibody in the blood peaks during infection and wanes, as the infection recedes. However, a waning antibody doesn’t mean that our immunity is low and we are susceptible to infection. T & B cells retain the memory of the infection and the the memory cells continue to stay in blood. If another infection starts on the body, memory cells charge up to produce a new bunch of antibodies to fight it

What a fantastic defence mechanism our body has!