Autoantibodies self-tolerance mechanism

Breakdown of tolerance mechanisms. There are at least two mechanisms for maintaining unresponsiveness to self The first is by specific deletion of self-reactive clones and the second by suppression. A failure of either of these two may result in an autoimmune disease. In normal, healthy individuals, antigen-binding, self-reactive B cells and the resultant low litres of autoantibodies are not uncommon. The origin of the self-reactive B cells is not clear, but there are four ways in which they may become activated. 

SLE is the prototype systemic autoimmune disease, with a hallmark of autoantibody production. The mechanism leading to loss of self-tolerance and production of autoantibodies is discussed in Section 2. 

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