Endogenous superantigen negative selection is another polyclonal model of clonal deletion whereby specific Vβ TCR-expressing T cells are deleted through interaction of their specific Vβ chain with endogenously-expressed superantigen bound to class II MHC (usually I E) on antigen presenting cells (Scherer et al., 1993).
Thus, intra- and extrathymic clonal deletion was evident in chimeras, but was not complete, revealing that both deletional and nondeletional mechanisms contribute to maintenance of tolerance in Treg-induced mixed chimeras.
Immune tolerance towards self-antigens is initiated in the thymus and involves clonal deletion of autoreactive T lymphocytes.
Self-directed lymphocytes may evade clonal deletion at ontogenesis but still remain harmless due to a mechanism called clonal anergy.
Second, the present findings argue for a better efficacy of clonal deletion than anergy of diabetogenic CD4 T-cells for the protection and reversal of autoimmune diabetes.
B cell central tolerance takes place in the bone marrow, hindering the development of autoreactive B cells by several mechanisms, such as clonal deletion and receptor editing (Nemazee, 2017).
Similarly, clonal deletion does not appear to be responsible for tumor outgrowth, as the number of 8.3-TCR CD8+ T cells does not decline with age or with tumor development.
Herein, we show that an octameric form of DEF has doubled the period of protection and reversal of disease by clonal deletion of diabetogenic CD4 T-cells in both the thymic and peripheral compartments.
Tolerance is in a way similar to the process of self-recognition where lymphoid clones, during development, baring self-reactive receptor are eliminated or rendered in active by "clonal deletion" leading to a state of accommodation and acceptance (anergic).
