Print. An orthopedic surgeon, or orthopaedic surgeon, is a surgeon who has been educated and trained in the diagnosis and preoperative, operative, and postoperative treatment of diseases and injuries of the musculoskeletal system. Orthopedic surgeons work closely with other health care providers and often serve as consultants to other physicians.
Reviewed October 2008. The immune system is composed of many interdependent cell types that collectively protect the body from bacterial, parasitic, fungal, viral infections and from the growth of tumor cells. Many of these cell types have specialized functions. The cells of the immune system can engulf bacteria, kill parasites or tumor cells, or kill viral-infected cells.
Disorders of the Immune System. Your immune system is your body's defense against infections and other harmful invaders. Without it, illnesses from bacteria or viruses, for example, would be constant. Your immune system is made up of special cells, tissues, and organs that work together to protect you.hey contain white blood cells that trap viruses, bacteria, and other invaders, including cancer cells. White blood cells are the cells of the immune system. They are made in one of your lymph organs, the bone marrow.