The main function of the immune system is to protect the human body against disease and other foreign bodies. The human immune system is a complex system that can identify threats to human health, distinguish these threats from the body’s own healthy tissues and eradicate these threats to keep humans healthy.
Many different parts of the body combine to make up the immune system. Lymph nodes, the spleen, bone marrow, lymphocytes and leukocytes all play key roles in immune function. Lymph nodes are small, bean-shaped structures that are found all through the human body. They store immune cells that fight infection and disease to keep the body healthy. The lymphatic system drains into the lymph nodes and brings all foreign antigens to the lymph nodes to be processed.
The spleen is full of white blood cells that fight off disease and infection. The spleen also recycles old red blood cells and removes them from the body. The bone marrow is found inside spongy bone throughout the body, and it produces red and white blood cells that help fight infection. Lymphocytes are immune cells that play a huge part in protecting the body against disease. They reside in the blood stream, the lymph nodes and the spleen. Leukocytes are white blood cells that identify foreign pathogens in the body and destroy them. For the immune system to function properly, all parts of the system must work together.