What is the immune system? The immune system is our body’s way of keeping out pathogens, fighting cancer, removing damaged/dead cells or tissues, and initiating repair of damage. As you learned in your anatomy and physiology classes, the immune system is divided into two main categories and each have specific jobs to ensure our body stays healthy.

Innate immunity is considered a nonspecific defense against pathogens that consists of physical and chemical barriers.

Adaptive immunity is our body’s specific defense against invaders and is governed by cells called lymphocytes. This division of our immune system creates memory cells that enable our bodies to more easily prevent reinfection if we come in contact with the same pathogen again.

Our immune system has 3 lines of defense:

• 1^st is physical and chemical barriers (like skin, mucous membranes, acid, saliva, tears, ear wax, hair, urine flow, and cilia movement).
• 2^nd is inflammatory processes including cells of inflammation and the complement system.
• 3^rd is the response of the adaptive immune system (T-cells, B-cells, antibodies, and memory cells).