The immune system is a network of biological processes that protects an organism against disease. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as objects such as wood splinters. In humans, immunodeficiency can be the result of a genetic disease, acquired conditions such as HIVAIDS, or the use of immunosuppressive medication.
About Immune system in brief
The immune system is a network of biological processes that protects an organism against disease. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as objects such as wood splinters. Disorders of the immune system can cause autoimmune diseases, inflammatory diseases and cancer. In humans, immunodeficiency can be the result of a genetic disease, acquired conditions such as HIVAIDS, or the use of immunosuppressive medication. The immune system protects its host from infection with layered defenses of increasing specificity. Physical barriers prevent pathogens such as bacteria and viruses from entering the organism. Several barriers protect organisms from infection, including mechanical, chemical, and biological barriers. In the lungs, coughing and sneezing mechanically eject pathogens and other irritants from the respiratory tract. mucus secreted by the respiratory and gastrointestinal tract serves to trap and entangle microorganisms. Vaginal secretions serve as a chemical barrier following a menarche, when they become slightly acidic. Since antibiotics do not target bacteria and do not affect fungi, oraliasis can lead to an\’overgrowth of candidiasis and vaginal candidiasis. As a result, the probability that bacteria and fungi will reach sufficient numbers to cause illness is reduced. In some cases, changing conditions in their environment, such as pH or available iron, can result in a higher incidence of candidal flora and candidiasis in some cases. The skin and respiratory tract secrete antimicrobial peptides such as the β-defensins.
Enzymes such as lyzzyme and phosphase A2 are also antibacterium. Vagina secretions are antibacteriac and serve as secretions in saliva, tears, breast milk, and semen. The stomach contains defensins and zinc to kill pathogens. Within the stomach, gastric acid serves as a defense against ingested pathogens, and within the genitourinary and gastrointestinal tracts serves as defense against oral candidiasis, candidal fungi, and candidal infections in the genital tract. In all animals, the innate immune system provides a preconfigured response to broad groups of situations and stimuli. In vertebrates, including humans, have even more sophisticated defense mechanisms, including the ability to adapt to recognize pathogens more efficiently. Both innate and adaptive immunity depend on the ability of theimmune system to distinguish between self and non-self molecules. In immunology, self molecules are components of an organism’s body that can be distinguished from foreign substances by the immunesystem. Conversely, non- Self molecules are those recognized as foreign molecules. One class of non-Self molecules are called antigens and are defined as substances that bind to specific immune receptors and elicit an immune response. If a pathogen breaches these barriers, the inherent immune system provides an immediate, but non-specific response. This improved response is then retained after the pathogen has been eliminated, in the form of an immunological memory, and allows the adaptive immune system to mount faster and stronger attacks each time.