What is peripheral tolerance mechanisms?

What is peripheral tolerance mechanisms?

Peripheral tolerance is the second branch of immunological tolerance, after central tolerance. Antigen-specific mechanisms of peripheral tolerance include direct inactivation of effector T cells by either clonal deletion, conversion to regulatory T cells (Tregs) or induction of anergy.

What is peripheral tolerance of T cells?

When self-reactive T cells escape into the periphery, peripheral tolerance ensures that they are deleted or become anergic (functionally unresponsive to antigen).

Which organ does peripheral tolerance occur?

thymus
Interactions between antigen-presenting cells (APCs) and lymphocytes are critical for self-tolerance, and these are known to take place in both thymus (central tolerance) and peripheral lymphoid tissues (peripheral tolerance).

What is the difference between peripheral and central tolerance?

Central tolerance is a state of immune tolerance that is induced originally in the thymus and bone marrow. Whereas, peripheral tolerance is a state of immune tolerance that is induced originally in the lymph nodes and other tissues.

Why is peripheral tolerance critical to barrier immunity?

Immune tolerance is important for normal physiology. Central tolerance is the main way the immune system learns to discriminate self from non-self. Peripheral tolerance is key to preventing over-reactivity of the immune system to various environmental entities (allergens, gut microbes, etc.).

Can you lack central tolerance but have peripheral tolerance?

Lymphocyte maturation (and central tolerance) occurs in primary lymphoid organs such as the bone marrow and the thymus. Central tolerance is not perfect, so peripheral tolerance exists as a secondary mechanism to ensure that T and B cells are not self-reactive once they leave primary lymphoid organs.

How many types of immunological tolerance are there?

There are two types of immune tolerance: self-tolerance and induced tolerance.

What is AIRE in central tolerance?

An essential molecule in the induction of central tolerance is Autoimmune Regulator (Aire). The AIRE gene was identified by positional cloning of a locus linked to a rare disease, Autoimmune-Polyendocrinopathy-Candidiasis-Ectodermal Dystrophy (APECED) (2, 3).

What is immunologic tolerance?

Immune tolerance, also referred to as immunological tolerance or immunotolerance, is an active state of unresponsiveness to specific antigens in an effort to prevent destructive over-reactivity of the immune system.

What are the mechanisms of peripheral tolerance?

Mechanisms of peripheral tolerance include direct inactivation of effector T cells by either clonal deletion, conversion to regulatory T cells (Tregs) or induction of anergy.

What is the role of B cell peripheral tolerance?

B cell peripheral tolerance is much less studied and is largely mediated by B cell dependence on T cell help. Antigens, which are present in generally low numbers can be ignored by the immune system without any further mechanism, since T cells have to be activated, prior to their migration to non-lymphoid tissues.

Why study peripheral T cell tolerance in animal models?

Regardless, a better understanding of peripheral T cell tolerance in animal models offers not only a mechanistic framework for further investigation of human disease pathogenesis, but also the promise of new therapeutic strategies to promote self tolerance in diseased individuals.

Are peripheral immune tolerance mechanisms most important for controlling mature T cells?

This then implies that peripheral immune tolerance mechanisms are most important for controlling mature T cells that bear a TCR of relatively low avidity for self pMHC and that escape to the periphery.