Question

Describe the 2 types of tolerance (Central and Peripheral)

Self tolerance—

Anergy—

Receptor editing—

Deletion--

Describe the 2 types of tolerance (Central and Peripheral)

Self tolerance—

Anergy—

Receptor editing—

Deletion--

Answer 1

Central tolerance is also known as negative selection, is the process of eliminating any developing T or B lymphocytes that are reacting to self. Through elimination of autoreactive lymphocytes, tolerance ensures that the immune system does not attack self peptides. In other words, is the 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. ( allergans, gut, microbes etc). It main purpose is to ensure that self- reative T cells and B cells which escaped from central tolerance do not cause autoimmune diseases.

Self tolerance is the ability to the immune system to recognize self produced antigens as a non-threat while appropriately mounting a response to foreign substances. Self tolerance regulation of immune effectors cells can be divided into 2 mechanisms termed as central and peripheral tolerance depending on where they take place. Central tolerance occurs in the organ of maturation for respective lymphocytes, the thymus for T cells, bone marrow for B cells. Peripheral tolerance occurs outside the organ of maturation, at the site of antigen recognition where T and B cells would ultimately begin to elicit an immune response.

Anergy is the mechanisms of peripheral tolerance. It is a state of inactivation in which the lymphocytes remain alive but are unable to respond to antigen.it is a reversible state.

Receptor editing is a process that occurs during the maturation of B cells, which are part of the adaptive immune system. This process forms part of central tolerance to attempt to change the specificity of the antigen receptor of sel- reactive immature B cells, to prevent apoptosis.

Clonal deletion is the removal through apoptosis of B cells and T cells that have expressed receptor for self before developing into fully immunocompetent lymphocytes. This prevents recognition and destruction of self host cells, making it a type of negative selection called central tolerance.