Immune System

White blood cells are the cells designed to seek out and eliminate invading organisms. White blood cells are called leukocytes. These cells are found throughout the body and are primarily produced and stored in the thymus, spleen and bone marrow. You may have heard the term lymph node used by your doctor. Lymph nodes are clumps of tissue that contain leukocytes and can be found in different locations throughout the body.

White blood cells are not all the same. While all white blood cells have common characteristics, these cells are also diversified to efficiently target different types of disease and invading organisms.

The lungs and intestines secrete mucus, which can trap microorganisms, preventing them from entering the bloodstream and tissues.

The human body is an amazing machine designed to be self-sufficient when it comes to well-being. The Microbial World gives great examples of how the body's built-in defense system responds to the invading pathogens that occur on a daily basis:



The gastric acid produced by the stomach not only aids in digestion but is also a chemical barrier that destroys many forms of ingested pathogens. Vomiting and diarrhea results when your body is trying to rid itself of a harmful bacterial infection.

Saliva, tears and breast milk contain antibacterial enzymes to help fight off harmful bacteria.

One of the most vital systems in the human body is the immune system, which is a network of specialized cells, tissues and organs that protect our bodies from potentially lethal invaders such as bacteria, viruses, fungi, microorganisms, parasites and other pathogens. The human body is constantly waging war against a barrage of invading microorganisms.

One of the first responses to infection by the immune system is inflammation.

Natural immunity - this is the type of immunity that human beings are born with. Every baby is born with antibodies that were passed on through its mother. Natural barriers such as the skin and protective substances in mucous membranes such as the mouth and eyes prevent harmful substances from entering the body.

Lymphocytes are important cells in the body's immune system defense. Lymphocytes are formed in bone marrow. The cells that remain in the marrow will become known as B lymphocytes. Other lymphocytes migrate to the thymus and become T lymphocytes. The B cells main function is to gather intelligence on any invading microorganisms or pathogens. Once the B cells have identified and "locked on" (creating antibodies) to the invaders, the T cells are released to help destroy the pathogens. The specialized antibodies remain in the body, ready to fight the same infection should it ever return.

Kids Health.org provides a clear picture about which cells in the body gather the intelligence information needed to carry out a tactical assault against any invading organisms and which cells are sent to the battle zone to swiftly and efficiently destroy the enemy.

Fever can sometimes help the immune system fight off infection because certain pathogens are unable to tolerate higher temperatures, which can also increase the mobility of leukocytes and the proliferation of T cells.

Coughing and sneezing are part of the natural immunity system where the body is trying to eject pathogens and irritants from the respiratory system.

As normal, healthy adult ages, he or she will catch fewer colds and flus as his or her immune system strengthens from repeated exposure.

Acquired immunity - this type of immunity develops over time. As a person is exposed to certain diseases and illness, the body produces antibodies that will fight off whatever bacterial or viral infection that the person was previously exposed to. This is how vaccinations work.

According to Ohio State University Medical Center, the immune system works in a couple of different ways to help protect your body from sickness and disease.