Your body is an ideal environment for many different microbes -- such as bacteria, fungi and parasites -- to thrive. To protect against diseases and infections, your immune system -- a complex network of your organs, tissues and cells -- either fights to keep these microbes out of your body or works to destroy them after they make their way inside.
Nonspecific
Known as innate, or nonspecific, immunity, your immune system's first line of defense against microbes consists of attempting to keep the microbes from even making it into your body. Innate immunity does not require a waiting period for your body to become acquainted with any potential infections, but is continually ready to take action against any microbes with which it comes in contact. Additionally, innate immunity is also programmed into you genetically, and your innate immunity is passed on to your offspring.
Adaptive
In contrast, specific, or adaptive, immunity is your immune system's second line of defense -- once microbes pass by innate immunity and make it into your body, specific immunity works to fight and destroy them. Specific immunity requires knowledge of the microbe that it is fighting, and comes with an ability to remember microbes it has fought against before. When this occurs, specific immunity is able to better grapple with the microbe, leading to a shorter bout of infection, as it has already built up a defense system.
Physical Barriers and Chemical Reactions
Innate immunity consists of mechanical barriers and chemical or biological factors. Mechanical barriers consist of the skin and mucous membranes, among others. The skin is considered to be an effective innate barrier to bacteria as no known bacterium can pass through unbroken skin, but punctures, cuts or scrapes may allow microbes to make their way into your body. Chemical factors of innate immunity include chemicals in the sweat, saliva and tears that can destabilize bacteria, and biological factors include the gastrointestinal tract flora, which create toxic substances to prevent bacteria from attaching to the tract.
Specific Immunity Building Methods
Specific immunity requires knowledge of the microbe invading the body before it can take action. This knowledge can be acquired through either natural or artificial methods. The natural method for creating specific immunity is by the body fighting off an infection for the first time. The artificial method for creating specific immunity is to introduce a variant of the infection to allow the body to create a defense system for fighting it off, as is the case with vaccinations.
References
- National Institute of Allergy and Infectious Diseases: What Is the Immune System?; October 2008
- Immune Defense Against Bacterial Pathogens: Innate Immunity; Todar's Online Textbook of Bacteriology; Kenneth Tolar, Ph.D.; 2011
- University of Hartford: Immune System; March 2001
- Immune Defense Against Bacterial Pathogens: Adaptive or Acquired Immunity; Todar's Online Textbook of Bacteriology; Kenneth Tolar, Ph.D.; 2011
- University of Maryland Medical Center: Immune Response- Overview; May 2008
- University of South Carolina School of Medicine: Microbiology and Immunology Mobile Index: Innate (Non-Specific Immunity)
Member Comments