Related topics: proceedings of the national academy of sciences , cells , immune cells , immune response , rheumatoid arthritis
Immune system
hideAn 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.
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News tagged with immune system
Meditation increases brain gray matter
Medicine & Health / Neuroscience
May 12, 2009 |
4.5 / 5 (34) |
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Push-ups, crunches, gyms, personal trainers -- people have many strategies for building bigger muscles and stronger bones. But what can one do to build a bigger brain? Meditate.
Implant-based cancer vaccine is first to eliminate tumors in mice
Nov 25, 2009 |
4.7 / 5 (31) |
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 ...
Radiation Review: Some People May be 'Allergic' to Cell Phones, Computers
May 15, 2009 |
3.4 / 5 (38) |
31
(PhysOrg.com) -- How exactly does the radiation from electromagnetic fields (EMF) affect the human body? Is it possible that cell phones, computer monitors, TVs, and other electronic devices - which operate ...
Study reveals H1N1 unexpected weakness
Dec 10, 2009 |
4.8 / 5 (19) |
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The H1N1 influenza virus has been keeping a secret that may be the key to defeating it and other flu viruses as well.
Researchers demonstrate that stem cells can be engineered to kill HIV
Medicine & Health / HIV & AIDS
Dec 08, 2009 |
4.9 / 5 (17) |
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(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.
Opposites attract -- how genetics influences humans to choose their mates
May 25, 2009 |
4.8 / 5 (16) |
3
New light has been thrown on how humans choose their partners, a scientist will tell the annual conference of the European Society of Human Genetics today. Professor Maria da Graça Bicalho, head of the Immunogenetics and ...
Researchers Build Artificial Immune System to Solve Computational Problems
Technology / Computer Sciences
Dec 03, 2009 |
4.8 / 5 (14) |
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(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 ...
Vaccine being developed to help smokers quit
Medicine & Health / Medications
Nov 20, 2009 |
4.3 / 5 (15) |
10
(PhysOrg.com) -- Glaxo-SmithKline has joined forces with Nabi Pharmaceuticals to produce a vaccine to help smokers give up their addiction permanently.
Scientists identify enzyme important in aging
Jul 10, 2009 |
5 / 5 (10) |
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The secret to longevity may lie in an enzyme with the ability to promote a robust immune system into old age by maintaining the function of the thymus throughout life, according to researchers studying an "anti-aging" mouse ...
British girl's heart heals itself after transplant
Jul 14, 2009 |
4.9 / 5 (10) |
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(AP) -- British doctors designed a radical solution to save a girl with major heart problems in 1995: they implanted a donor heart directly onto her own failing heart.
A major step in making better stem cells from adult tissue
Oct 18, 2009 |
4.9 / 5 (10) |
0
A team led by scientists from The Scripps Research Institute has developed a method that dramatically improves the efficiency of creating stem cells from human adult tissue, without the use of embryonic cells. The research ...
New way to kill cancer found using body's immune system
Jul 21, 2009 |
5 / 5 (9) |
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(PhysOrg.com) -- Scientists have discovered a new way of killing cancer cells in a breakthrough that could eventually lead to new treatments for a range of different cancers.
New Synthetic Molecules Trigger Immune Response to HIV and Prostate Cancer
Nov 05, 2009 |
4.7 / 5 (9) |
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(PhysOrg.com) -- Researchers at Yale University have developed synthetic molecules capable of enhancing the body’s immune response to HIV and HIV-infected cells, as well as to prostate cancer cells. Their ...
New trigger for chronic inflammation in rheumatoid arthritis discovered
Jun 28, 2009 |
4.6 / 5 (8) |
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(PhysOrg.com) -- A signal molecule made by the human body that triggers the immune system into action may be important in rheumatoid arthritis, according to new research published today in Nature Medicine. The au ...
Immune therapies finally working against cancer
May 31, 2009 |
5 / 5 (7) |
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(AP) -- First there was surgery, then chemotherapy and radiation. Now, doctors have overcome 30 years of false starts and found success with a fourth way to fight cancer: using the body's natural defender, ...
