Build your DEFENCE

Understand your immune system and know how to improve it to fight diseases

- ROHINI DINIZ

The human body has an intrinsic, in-built mechanism that defends it against potentially harmful foreign agents. Known as the immune system, it is a complex and integrated system of cells, tissues and organs that have specialised roles in defending against foreign substances and pathogenic microorganisms including bacteria, viruses and fungi.

But this same immune system sometimes attacks the body’s own tissues and cells leading to chronic inflammation, development of allergic reactions and autoimmune disease. For the immune system to function optimally, there has to be a delicate balance between the destruction of invading pathogens and avoidance of self-destruction.

Immune system cells are formed in the bone marrow and circulate through the blood and lymphs to peripheral tissues. The organs of the immune system include the thymus, spleen and lymph nodes. The immune system is broadly divided into innate immunity and adaptive immunity.

Innate immunity involves immediate, non-specific responses to foreign invaders and is the first line of defence against foreign substances and pathogenic microorganisms that does not involve immunologic memory of pathogens. The innate immune system comprises various anatomical barriers such as the skin, stomach acid, normal gut microflora and also soluble factors and phagocytic cells. Soluble factors include the complement system that consists of a biochemical network of more than 30 proteins in the plasma and on cellular surfaces that are a key component of the innate immunity, acute phase reactant proteins and messenger proteins called cytokines.