Related topics: proceedings of the national academy of sciences , cells , immune cells , immune response , rheumatoid arthritis



Immune system

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An immune system is a collection of biological processes within an organism that protects against disease by identifying and killing pathogens and tumour cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own healthy cells and tissues in order to function properly. Detection is complicated as pathogens can evolve rapidly, producing adaptations that avoid the immune system and allow the pathogens to successfully infect their hosts.

To survive this challenge, multiple mechanisms evolved that recognize and neutralize pathogens. Even simple unicellular organisms such as bacteria possess enzyme systems that protect against viral infections. Other basic immune mechanisms evolved in ancient eukaryotes and remain in their modern descendants, such as plants, fish, reptiles, and insects. These mechanisms include antimicrobial peptides called defensins, phagocytosis, and the complement system. Vertebrates such as humans have even more sophisticated defense mechanisms. The immune systems of vertebrates consist of many types of proteins, cells, organs, and tissues, which interact in an elaborate and dynamic network. As part of this more complex immune response, the human immune system adapts over time to recognise specific pathogens more efficiently. This adaptation process is referred to as "adaptive immunity" or "acquired immunity" and creates immunological memory. Immunological memory created from a primary response to a specific pathogen, provides an enhanced response to secondary encounters with that same, specific pathogen. This process of acquired immunity is the basis of vaccination.

Disorders in the immune system can result in disease. Immunodeficiency occurs when the immune system is less active than normal, resulting in recurring and life-threatening infections. Immunodeficiency can either be the result of a genetic disease, such as severe combined immunodeficiency, or be produced by pharmaceuticals or an infection, such as the acquired immune deficiency syndrome (AIDS) that is caused by the retrovirus HIV. In contrast, autoimmune diseases result from a hyperactive immune system attacking normal tissues as if they were foreign organisms. Common autoimmune diseases include Hashimoto's Thyroiditis, rheumatoid arthritis, diabetes mellitus type 1 and lupus erythematosus. Immunology covers the study of all aspects of the immune system which has significant relevance to human health and diseases. Further investigation in this field is expected to play a serious role in promotion of health and treatment of diseases.

For more information about Immune system, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with immune system

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Researchers demonstrate that stem cells can be engineered to kill HIV

Medicine & Health / HIV & AIDS

created Dec 08, 2009 | popularity 4.9 / 5 (13) | comments 0

(PhysOrg.com) -- UCLA AIDS Institute researchers have for the first time demonstrated that human blood stem cells can be engineered to target and kill HIV-infected cells.


'Shoot-'em-up' video game increases teenagers' science knowledge

Biology / Other

created Dec 08, 2009 | popularity 4.2 / 5 (6) | comments 2

While navigating the microscopic world of immune system proteins and cells to save a patient suffering from a raging bacterial infection, young teenage players of the "Immune Attack" video game measurably improved their understanding ...


Researchers Build Artificial Immune System to Solve Computational Problems

Researchers Build Artificial Immune System to Solve Computational Problems

Technology / Computer Sciences

created Dec 03, 2009 | popularity 4.8 / 5 (13) | comments 0

(PhysOrg.com) -- By mimicking the way that a living body acquires immunity to disease through vaccination, researchers have designed an artificial immune system to solve optimization problems more effectively ...


Scientists reveal key structure from ebola virus

Medicine & Health / Research

created Dec 08, 2009 | popularity 5 / 5 (2) | comments 0

Scientists at The Scripps Research Institute have determined the structure of a critical protein from the Ebola virus, which, though rare, is one of the deadliest viruses on the planet killing between 50 and 90 percent of ...


Fatty food can weaken the immune system

Medicine & Health / Health

created Dec 08, 2009 | popularity not rated yet | comments 0

Fresh evidence that fatty food is bad for our health has come to light: mice fed a lard-based diet over a long period got worse at fighting bacteria in the blood, reveals a thesis from the Sahlgrenska Academy at the University ...


Microbes help mothers protect kids from allergies

Medicine & Health / Research

created Dec 07, 2009 | popularity not rated yet | comments 1

A pregnant woman's exposure to microbes may protect her child from developing allergies later in life. Researchers in Marburg, Germany find that exposure to environmental bacteria triggers a mild inflammatory response in ...


Dutch PhD develops fast method for preparing flu vaccine

Medicine & Health / Research

created Dec 07, 2009 | popularity 5 / 5 (1) | comments 0

(PhysOrg.com) -- A shortage of flu vaccines may soon become a thing of the past. Researcher Manon Cox has designed an alternative process for producing large quantities of safe and effective vaccines at twice to four times ...


Implant-based cancer vaccine is first to eliminate tumors in mice

Implant-based cancer vaccine is first to eliminate tumors in mice

Medicine & Health / Cancer

created Nov 25, 2009 | popularity 4.7 / 5 (31) | comments 7

(PhysOrg.com) -- A cancer vaccine carried into the body on a carefully engineered, fingernail-sized implant is the first to successfully eliminate tumors in mammals, scientists report this week in the journal ...


Scientists reveal malaria parasites' tactics for outwitting our immune systems

Scientists reveal malaria parasites' tactics for outwitting our immune systems

Medicine & Health / Research

created Nov 30, 2009 | popularity 4.8 / 5 (6) | comments 1

Malaria parasites are able to disguise themselves to avoid the host's immune system, according to research funded by the Wellcome Trust and published today in the journal Proceedings of the National Academy of ...


Researchers discover biological basis of 'bacterial immune system'

Chemistry / Biochemistry

created Nov 30, 2009 | popularity 4.8 / 5 (4) | comments 1

(PhysOrg.com) -- Bacteria don’t have easy lives. In addition to mammalian immune systems that besiege the bugs, they have natural enemies called bacteriophages, viruses that kill half the bacteria on Earth every two days.


smoking, cigarette

Vaccine being developed to help smokers quit

Medicine & Health / Medications

created Nov 20, 2009 | popularity 4.3 / 5 (15) | comments 10

(PhysOrg.com) -- Glaxo-SmithKline has joined forces with Nabi Pharmaceuticals to produce a vaccine to help smokers give up their addiction permanently.


Researchers discover biological basis of 'bacterial immune system'

Biology / Cell & Microbiology

created Nov 25, 2009 | popularity 4.8 / 5 (4) | comments 0

Bacteria don't have easy lives. In addition to mammalian immune systems that besiege the bugs, they have natural enemies called bacteriophages, viruses that kill half the bacteria on Earth every two days.


Scientists discover genetic pattern that indicates early-stage lung cancer

Medicine & Health / Cancer

created Dec 01, 2009 | popularity 4 / 5 (1) | comments 0

Wistar Institute researchers and collaborators from the University of Pennsylvania and New York University have identified immune system markers in the blood which indicate early-stage lung tumors in people at high risk for ...


Good stress response enhances recovery from surgery, study shows

Medicine & Health / Research

created Dec 01, 2009 | popularity not rated yet | comments 0

The right kind of stress response in the operating room could lead to quicker recovery for patients after knee surgery, according to a new study led by Stanford University School of Medicine researchers. The results could ...


Gene mismatch influences success of bone marrow transplants

Medicine & Health / Genetics

created Nov 22, 2009 | popularity 4 / 5 (1) | comments 0

A commonly inherited gene deletion can increase the likelihood of immune complications following bone marrow transplantation, an international team of researchers reports in the November 22 advance online issue of Nature Ge ...




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