Navigation Links
Central tolerance


Central tolerance is the mechanism by which newly developing T cells and B cells are rendered non-reactive to self.[1] The process is required due to the random generation of receptor specificities that occurs during T cell and B cell differentiation, whereby a proportion of the cells generated are self-reactive (recognise the component self antigens of the host).

In mammals the process occurs in the thymus (T cells)[2][3] and bone marrow (B cells), when maturing lymphocytes are exposed to self antigens. Self antigens are present in both organs due to endogenous expression within the organ and importation of antigen due to circulation from peripheral sites. In the case of T cell central tolerance, additional sources of antigen are made available in the thymus by the action of the transcription factor AIRE.

After exposure to self antigens, T cells and B cells become immunologically tolerant (non-reactive) in a number of ways :

Genetic defects in these processes lead to autoimmunity, such as in the human syndromes APS-1 and IPEX.

References

  1. ^ http://www-immuno.path.cam.ac.uk/~immuno/part1/lec11/lec11_97.html
  2. ^ Sprent J, Kishimoto H (2001). "The thymus and central tolerance". Philos Trans R Soc Lond B Biol Sci 356 (1409): 609-16. PMID 11375064.
  3. ^ Hogquist K, Baldwin T, Jameson S (2005). "Central tolerance: learning self-control in the thymus". Nat Rev Immunol 5 (10): 772-82. PMID 16200080.
  4. ^ Halverson R, Torres R, Pelanda R (2004). "Receptor editing is the main mechanism of B cell tolerance toward membrane antigens". Nat Immunol 5 (6): 645-50. PMID 15156139.

'"/>


(Date:11/19/2019)... ... 2019 , ... Modern Living with kathy ireland® ... Founder Lisa Hall to discuss their simple, authentic and all-natural skincare products. , ... with eighty-four trace minerals. These uniquely formulated products are created with food-grade ingredients ...
(Date:11/19/2019)... ... November 19, 2019 , ... Bright Day Big Blocks, http://www.brightdaybigblocks.com , ... the launch of their Gift Of Play initiative. Organizations are encouraged to simply ... Co-Founders of Bright Day Big Blocks, Laurel Tucker and David Krishock decided earlier this ...
(Date:11/19/2019)... ... November 19, 2019 , ... iPatientCare, a pioneer in ... solutions, announces Virtual User Conference (VUCON), which will highlight the impact of patient ... experience. , VUCON sessions are designed to demonstrate the new ...
(Date:11/16/2019)... ... November 15, 2019 , ... As demand for legal medical ... via well-managed dispensaries becomes more and more important, both for consumers and as ... state-of-the-art, online, custom cannabis business plans is now increasing its support for marijuana ...
(Date:11/15/2019)... ... November 15, 2019 , ... Spectrum Vision ... Top Long Island Workplaces for 2019. The recently announced rankings honor those organizations ... Newsday worked in partnership with Energage to conduct surveys into organizational health and ...
Breaking Medicine News(10 mins):
Other medicine definition