Disease fighting is an important and vital function that several body systems and parts collaborate to perform. There are multiple lines of defense to fight disease-causing pathogens or germs such as viruses, bacteria, parasites, and fungi. The immune system is formed from a complex network of organs and cells that work together to protect the body.
Lymphoid Organs
The University of Chicago Medical Center explains that the organs of the immune system are called lymphoid organs. These organs are involved in the growth, development and release of immune cells. Blood vessels and lymphatic vessels then carry the immune cells to fight infection in all the tissues of the body. Lymphoid organs include the adenoids, two small glands located at the back of the nasal passage; the appendix, a small tube that is attached to the large intestine; and lymph nodes, small organs located throughout the body and connected by a network of lymphatic vessels. Other immune organs include the spleen, tonsils, bone marrow, thymus and blood vessels.
White Blood Cells
White blood cells or leukocytes fight infection in the body. There are a variety of white blood cells and each has a role in fighting diseases in the body, as outlined by the University of Maryland Medical Center. They help to heal wounds by ingesting debris and other dead matter, protect against cancerous cell mutations, and fight foreign bodies that enter the bloodstream. Types of white cells include neutrophils, eosinophils, monocytes, granulocytes and lymphocytes.
Skin
The American Osteopathic College of Dermatology notes that the skin--a tough, flexible and waterproof covering--acts as the first barrier to prevent pathogens from entering the body. The skin is composed of three layers, the epidermis, dermis and an innermost fat layer. Selective materials are allowed to enter and leave the body through the skin. The epidermis is made up of a layers of dead skin cells that serve as a major barrier against disease causing pathogens that try to enter the body. Specialized cells called melanocytes or pigment cells protect the body against damage from UV radiation from sunlight. The dermis layer of skin contains blood vessels that have a constant stream of immune cells flowing through them. These cells are ready to fight any pathogens that cross into the body through a cut, scrape, or wound in the skin.
