Copyright © Philip M. Parker, INSEAD. Terms of Use.
Definition: Immune System |
Immune SystemNoun1. A system (including the thymus and bone marrow and lymphoid tissues) that protects the body from foreign substances and pathogenic organisms by producing the immune response. Source: WordNet 1.7.1 Copyright © 2001 by Princeton University. All rights reserved. |
| Domain | Definitions |
Medicine | The organs, cells, and molecules responsible for the recognition and disposal of foreign("non-self")material which enters the body. Source: European Union. (references) |
Source: compiled by the editor from various references; see credits. | |
(From Wikipedia, the free Encyclopedia)
The immune system of a multicellular organism acts as a defense against pathogens, such as viruses, bacteria, parasites, and some poisons. There are several variations of immune systems throughout species, and sometimes more than one immune system within the same organism (for example, the human brain has its own immune system that is separate from the "normal" one).
The Latin term immunis means exempt, referring to protection against foreign agents. The recognition of what is foreign is found in all life. In self-pollinating plants, a pollen grain landing on the stigma of a flower will send a pollen tubule down the style to the ovary for fertilization. A pollen grain from a genetically distinct plant will not germinate or the pollen tubule, once formed, will disintegrate in the style. In cross-pollinating species,
self-marked pollen grains disintegrate, while nonself grains germinate and fertilize.
We may conceive of an arrangement where the cells of self are marked, so that they are not attacked by its own defense mechanism. But not all foreign cells may be destroyed since some must be assimilated for nourishment. Therefore, the immune system must have the capacity to detect self and some nonself. But since self needs to assimilate some nonself for its survival, it cannot mark itself. It is easier to mark potentially dangerous selves. But if only certain nonselves are marked, how does the body prepare to defend itself from selves not
seen? The defense system must have the capacity to transform itself to deal with future dangers. It must also have the capacity to change, since the self itself evolves with time.
Many organisms have an immune system. This immune system consists of an innate immunity which began in early eukaryotes such as the amoeba and generally consists of a set of mostly hard-wired responses to pathogens and does not change of the lifetime of the organism. Adaptive immunity in which the response to pathogens changes during the lifetime of an individual, appeared somewhat abruptly in evolutionary time with the appearance of cartilaginous (jawed) fish. Organisms that posess an adaptive immunity also posess an innate immunity and many of the mechanisms between the systems are common, so it not always possible to draw a hard and fast boundary between the individual components involved in each, despite the clear difference in operation. Humans have both an innate and an adaptive immune system.
The adaptive immune system functions over extended time frames and may take days or weeks after an initial infection to have an effect. However, most organisms are under constant assult from pathogens, which must be kept in check by the fast-acting innate immune system. Innate immunity does not recognize specific pathogens, but rather fights general classes of pathogens using less specific defenses. Plants and many animals do not posses an adaptive immune system and instead rely on innate immunity.
The first defense includes barriers to infection such as skin and mucus coating of the gut and airways. Pathogens which penetrate these barriers encounter anti-microbial molecules that restrict the infection. Pathogens may also be recognized by molecules that distinguish generally between classes of pathogens such as Gram-negative or Gram-positive bacteria. These pathogen-recognition molecules activate the expression of defensive molecules which target the infection.
The current understanding of innate immunity is very limited. Recent studies of innate immunity have made use of model organisms that lack adaptive immunity such as the plant Arabidopsis thaliana, the fly Drosophila melanogaster, and the worm Caenorhabditis elegans.
The adaptive immune system, which is much better understood than the innate immune system, is based on immune cells called leukocytes (or white blood cells) that are produced by stem cells in the bone marrow. The immune system can be divided into two parts. Many species, including mammals, have the following type:
There are a number of different autoimmune disorders, such as lupus erythematosus, multiple sclerosis, psoriasis, and rheumatoid arthritis. In these the self-recognition ability of the immune system fails and it attacks a part of the patient's own body.
By contrast AIDS, the "Acquired Immune Deficiency Syndrome" is an infectious disease, transmitted by the HIV virus, which causes degeneration of the body's immune system. Recognizing self and non-self: the problem of immunity
Structure of the immune system
Innate immune system
Adaptive immune system
Disorders of the human immune system
Source: adapted by the editor from Wikipedia, the free encyclopedia under a copyleft GNU Free Documentation License (GFDL) from the article "Immune system."
| Domain | Title |
Books | |
Theater & Movies | |
Source: compiled by the editor from various references; see credits. | |
| Subject | Topic | Quote |
Health | There are many components of the immune system. (references) | |
It is the immune system that defends our bodies against germs. (references) | ||
These antibodies are produced by the body's own immune system. (references) | ||
Source: compiled by the editor from ICON Group International, Inc.; see credits. | ||
Expressions using "immune system": Digital Immune System ♦ Immune system disorders ♦ modulator of the immune system. Additional references. | |
| Source: compiled by the editor from various references; see credits. |
| The following statistics estimate the number of searches per day across the major English-language search engines as identified by various trade publications. Hyperlinks lead to commercial use of the expression at Amazon.com. |
| Expression | Frequency per Day |
immune system | 959 |
boost immune system | 134 |
immune system supplement | 66 |
immune system support | 49 |
immune system picture | 43 |
immune system vitamin | 39 |
immune system disease | 38 |
digital immune system | 28 |
immune system disorder | 27 |
the human immune system | 26 |
| Source: compiled by the editor from various references; see credits. | |
| Language | Translations for "immune system"; alternative meanings/domain in parentheses. | |
Danish | immunsystem, immunitetssystem. (various references) | |
Dutch | immuunsysteem, immunologisch systeem, afweersysteem. (various references) | |
Finnish | immuunijärjestelmä. (various references) | |
French | système immunitaire. (various references) | |
German | immunsystem. (various references) | |
Greek | ανοσοποιητικό σύστημα. (various references) | |
Italian | sistema immunitario. (various references) | |
Pig Latin | immuneay ystemsay.(various references) | |
Portuguese | sistema imunológico, sistema imunitário. (various references) | |
Spanish | sistema inmunológico, sistema inmunitario. (various references) | |
Swedish | immunsystem, immunapparat. (various references) | |
| Source: compiled by the editor from various translation references. | ||
Scrabble® Enable2K-Verified Anagrams | |
| Words within the letters "e-e-i-m-m-m-n-s-s-t-u-y" | |
-3 letters: immensest. | |
-4 letters: mismeets, mistunes, muteness, semimute, syenites, tenesmus, yummiest. | |
-5 letters: emetins, immense, immunes, messmen, metisse, mimeses, minuets, minuses, minutes, mismeet, missent, mistune, mummies, mustees, mutines, mutisms, nemesis, sestine, siemens, stymies, summits, syenite, tissuey, tsimmes, tummies, yummies. | |
| Source: compiled by the editor from various references; see credits. SCRABBLE® is a registered trademark. All intellectual property rights in and to the game are owned in the U.S.A and Canada by Hasbro Inc., and throughout the rest of the world by J.W. Spear & Sons Limited of Maidenhead, Berkshire, England, a subsidiary of Mattel Inc. Mattel and Spear are not affiliated with Hasbro. | |
Hexadecimal (or equivalents, 770AD-1900s) (references)49 6D 6D 75 6E 65 53 79 73 74 65 6D |
| Leonardo da Vinci (1452-1519; backwards) (references)
|
Binary Code (1918-1938, probably earlier) (references)01001001 01101101 01101101 01110101 01101110 01100101 00100000 01010011 01111001 01110011 01110100 01100101 01101101 |
HTML Code (1990) (references)I m m u n e   S y s t e m |
ISO 10646 (1991-1993) (references)0049 006D 006D 0075 006E 0065 0053 0079 0073 0074 0065 006D |
Encryption (beginner's substitution cypher): (references)4379798780712539185867179 |
| 1. Definition 2. Crosswords 3. Usage: Commercial 4. Quotations: Non-fiction | 5. Expressions 6. Expressions: Internet 7. Translations: Modern 8. Anagrams | 9. Orthography 10. Bibliography |
Copyright © Philip M. Parker, INSEAD. Terms of Use.
