Mechanisms of autoimmunity: a role for cross-reactive idiotypes.

Ehrlich was rarely given to trivial pronouncements and his recognition of the central importance of the distinction between self and non-self by the immune system, embodied in his concept of 'horror autotoxicus'(1), is no exception. This is despite the apparent paradox of the idiotype network in which antibodies recognize self-epitopes on other antibody molecules or antigen receptors as part of the normal process of immune regulation. In this review Anne Cooke and her colleagues examine the possible factors which may contribute to the breakdown of self-tolerance and the establishment of autoimmune states.