parts of the immune system

The immune system is made up of various organs, tissues and cells that work together to protect the body against bacteria and foreign organisms. It acts as a barrier against invaders, attacking the organisms that try to reach within the body and cause a disease. As astonishing as this sounds, most of us are still in the dark about the basic parts of the immune system and their functions. To fix that, let’s take a closer look at what this intricate mechanism does for us on a daily basis.

The lymph system

This essential part of the immune system consists of a structure of lymphatic vessels which carry lymph throughout the body, the fluid which comprises white blood cells. The main objective of the lymphatic system is to help the body discard toxins. The major parts of the lymphatic system are the thymus and the bone marrow.

The thymus

Located between the heart and the breast bone, the thymus’ objective is to create T-cells. These are highly essential for babies who need the thymus working at full strength in order to survive. An adult could live without the thymus, with the other components of the immune system taking over its tasks.

The spleen

Positioned in the left upper part of the abdomen, the spleen has to filter blood, searching for foreign cells and removing useless blood cells. It also fights against bacteria and other substances and its structure resembles that of a big lymph node. Adults can live without this organ, but they will get sick more frequently than a person who has a spleen.

The bone marrow

Charged with producing new red and white blood cells, the bone marrow is a soft tissue within the long bones of the spine, pelvis, legs and arms. The stem cells produced by the bone marrow have the ability of branching off and transforming into various cell types. Comprising 4% of a human’s body mass, bone marrow plays various roles within our bodies. The bone marrow barrier doesn’t allow defective blood cells from departing from the marrow.

White blood cells

Also known as leukocytes, the white blood cells’ objective is to find and kill harmful organisms. Leukocytes are stored in the bone marrow, the spleen or the thymus and they travel within the body, monitoring germs and odd substances.


Produced by white blood cells, antibodies are also known as immunoglobulins. As Y shaped proteins, they bind to different toxins, deactivating their harmful actions. Plasma cells produce antibodies in order to pinpoint and get rid of germs and viruses.

The complement system

As a series of 30 proteins travelling freely in blood plasma, the complement system aids antibodies to destroy pathogens. Produced in the liver, complements work side by side with antibodies, signaling whenever a cell has to be removed.


All the parts of the immune system play essential roles within our bodies. To work together against diseases, the components of the immune system spread out in a layered defense system which must hunt down manifold harmful agents, ranging from viruses to worms. Since pathogens can quickly evolve, the immune system has to be on its toes and raise as many barriers between viruses and the body with the aid of its defense mechanisms.

For more information about the immune system, check out All You Need to Know about Immune Health.