What is central tolerance of T cells?
What is central tolerance of T cells?
In the human immune system, central tolerance (also known as negative selection) is the process of eliminating any developing T or B lymphocytes that are reactive to self. In mammals, B cells mature in the bone marrow and T cells mature in the thymus.
Which type of lymphocytes undergoes central tolerance?
Lymphocytes with receptors specific for self-antigens are deleted at an early stage in lymphoid cell development. This process is called central tolerance and allows self-reactive B and T cells to be removed. Lymphocytes that do not receive survival signals undergo apoptosis.
What is the difference between central and peripheral T lymphocyte 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.
What is central tolerance mechanism?
Central tolerance refers to the regulatory mechanisms that occur at the early stages of B cell development in the bone marrow, when B cells carry a surface antigen receptor of the IgM class but are not fully mature.
When does central tolerance occur in a lymphoid cell?
Lymphocytes with receptors specific for self-antigens are deleted at an early stage in lymphoid cell development. This process is called central tolerance and allows self-reactive B and T cells to be removed.
Why is it important to have a T lymphocyte?
T lymphocyte tolerance is particularly important, because it impacts B-cell tolerance as well, through the requirement of T cell help in antibody responses. Thus, failure of T-cell tolerance can lead to many different autoimmune diseases.
Where does the tolerance of T cells begin?
Thus, failure of T-cell tolerance can lead to many different autoimmune diseases. The tolerance of T cells begins as soon as a T-cell receptor is formed and expressed on the cell surface of a T-cell progenitor in the thymus.
Is the thymus part of the central tolerance system?
Tolerance mechanisms that operate in the thymus before the maturation and circulation of T cells are referred to as “central tolerance.” However, not all antigens that T cells need to be tolerant of are expressed in the thymus, and thus central tolerance mechanisms alone are insufficient.
