ABSTRACT
Besides decreases or increases in the normal immune response, namely direct immunotoxicity and hypersensitivity, a third situation related to immunotoxicity is autoimmunity (Bigazzi, 1994; Kammuller et al., 1989; Kilburn and Warshaw, 1994). Nowadays, autoimmunity is no longer considered to be basically a consequence of immune stimulation, as it once was considered to be, together with hypersensitivity. However, it is increasingly apparent that some common fundamental mechanisms can lead to immune responses potentially resulting either in hypersensitivity or in autoimmune reactions (Griem et al., 1998).
