Central tolerance

(noun)

The ability for T-cells to avoid perceiving normal host molecules as foreign antigens.

Related Terms

Examples of Central tolerance in the following topics:

  • Clonal Selection and Tolerance

    • Central tolerance is the mechanism by which newly developing T cells and B cells are rendered non-reactive to self.
    • The concept of central tolerance was proposed in 1959 as part of a general theory of immunity and tolerance.
    • Central tolerance is distinct from periphery tolerance in that it occurs while cells are still present in the primary lymphoid organs (thymus and bone-marrow), prior to export into the periphery.
    • Negative selection of developing lymphocytes is an important mechanism for maintaining central tolerance.
    • Describe the importance of central and peripheral tolerance and distinguish between positive and negative clonal selection

  • The Political Revolution

    • The American Enlightenment promoted ideas of individual liberty, republican government, and religious toleration.
    • Politically, the age is distinguished by an emphasis upon liberty, democracy, republicanism, and religious tolerance – culminating in the drafting of the United States Declaration of Independence and the U.S.
    • As Outram notes, the Enlightenment comprised "many different paths, varying in time and geography, to the common goals of progress, of tolerance, and the removal of abuses in Church and state. "
    • Thomas Jefferson and Ben Franklin were among the five, and their leadership was central to the American Enlightenment.

  • Louis XIV and the Huguenots

    • The Edict treated some, although not all, Protestants with tolerance and opened a path for secularism.
    • The Edict gained a new significance when Louis XIV, known as the Sun King, broke the post-Nantes tradition of relative religious tolerance in France and in his efforts to fully centralize the royal power, began to persecute the Protestants.
    • The experiment of religious toleration in Europe was effectively ended for the time being.
    • However, French society would sufficiently change by the time of Louis' descendant, Louis XVI, to welcome toleration in the form of the 1787 Edict of Versailles, also known as the Edict of Tolerance.
    • In this age of absolutism in Europe, Louis XIV's France was a leader in the growing centralization of power.

  • Genghis Khan

    • Genghis Khan ruled between 1206 and 1227, expanding trade across Asia and into eastern Europe, enacting relatively tolerant social and religious laws, and leading devastating military campaigns that left local populations depleted and fearful of the brutal Mongol forces.
    • He initially forged the Mongol Empire in Central Asia with the unification of the Mongol and Turkic confederations on the Mongolian plateau in 1206.
    • Then Mongol forces invaded westward into Central Asia including:
    • These conquests seriously depopulated large areas of central Asia and northeastern Iran, complicating the image of Genghis Khan as a peaceful ruler practicing religious tolerance.
    • Even populations that appreciated the new legal code and relative religious tolerance did not have much free will when it came to Mongol advances.

  • Maryland

    • The Calvert family recruited Catholic aristocrats and Protestant settlers for Maryland, luring them with generous land grants and a policy of religious toleration.
    • In 1649, Maryland passed the Maryland Toleration Act, also known as the Act Concerning Religion, a law mandating religious tolerance for Christians.
    • Passed by the assembly of the Maryland colony, it was the first law requiring religious tolerance in the British North American colonies.
    • Full religious toleration would not be restored in Maryland until the American Revolution.
    • In the late colonial period, the southern and eastern portions of the province continued their tobacco economy, but as the revolution approached, northern and central Maryland increasingly became centers of wheat production.

  • Biofilms, Persisters, and Antibiotic Tolerance

    • Biofilms and persisters are bacterial communities responsible for chronic diseases and antibiotic tolerance.
    • Persisters are multidrug tolerant cells present in all bacterial populations.
    • Persisters are not mutants, but rather phenotypic variants of the wild-type that upon inoculation produce a culture with similar levels of tolerance.
    • Biofilms and persisters are the cause of multidrug tolerance.
    • Explain the role of biofilms and persisters in multidrug tolerance, distinguishing this from multidrug resistance

  • The Rise of Christianity

    • The Great Persecution officially ended in April of 311, when Galerius, senior emperor of the Tetrarchy, issued an edict of toleration which granted Christians the right to practice their religion, though it did not restore any property to them.
    • Constantine, Caesar in the Western empire and Licinius, Caesar in the East, also were signatories to the edict of toleration.
    • In Africa, the Donatists, who protested the election of the alleged traditor Caecilian to the bishopric of Carthage, continued to resist the authority of the central Church until after 411.
    • In 313, Constantine and Licinius announced in the Edict of Milan "that it was proper that the Christians and all others should have liberty to follow that mode of religion which to each of them appeared best," thereby granting tolerance to all religions, including Christianity.
    • The Edict of Milan went a step further than the earlier Edict of Toleration by Galerius in 311 and returned confiscated Church property.

  • Analgesia: Relief from Pain

    • Analgesic drugs act in various ways on the peripheral and central nervous systems; they include paracetamol (para-acetylaminophenol, also known in the U.S. as acetaminophen), the non-steroidal anti-inflammatory drugs (NSAIDs) such as the salicylates (such as aspirin, shown in ), and opioid drugs such as morphine and opium.
    • The exact mechanism of action of paracetamol/acetaminophen is uncertain, but it appears to be acting centrally rather than peripherally (in the brain rather than in nerve endings).
    • Dosing of all opioids may be limited by opioid toxicity (confusion, respiratory depression, myoclonic jerks, and pinpoint pupils) and seizures (tramadol), but there is no dose ceiling in patients who accumulate tolerance.
    • When used appropriately, opioids and similar narcotic analgesics are otherwise safe and effective; however, risks such as addiction and the body becoming used to the drug (tolerance) can occur.
    • The effect of tolerance means that frequent use of the drug may result in its diminished effect so, when safe to do so, the dosage may need to be increased to maintain effectiveness.

  • Hyperthermophilic Archaea, H2, and Microbial Evolution

    • Some bacteria are even able to tolerate temperatures of around 100°C (212°F).
    • One extraordinary heat-tolerant hyperthermophile is the recently discovered Strain 121, an archaeon living at 121°C in the Pacific Ocean.
    • The current record growth temperature is 122°C for Methanopyrus kandleri ,an archaeon found in a Central Indian Ridge.

  • Hooverville

    • Generally, however, Hoovervilles were tolerated or ignored out of necessity.
    • Notable Hoovervilles were in Central Park and Riverside Park in New York City, where scores of homeless families camped out.