A Proposed Classification of the Immunological Diseases

August 2006 | Volume 3 | Issue 8 | e297 A century ago Paul Ehrlich proposed that immune reactivity against self, which he called “horror autotoxicus” and which is now called autoimmunity, would be incompatible with life because of potentially devastating consequences for the host. But Ehrlich was proven wrong after the demonstration of autoantibodies and the emergence of a theoretical basis for autoreactivity [1]. Conceptually, autoimmunity is viewed as a defect of either B or T lymphocyte selection, with aberrant lymphocytic responses to autoantigens [2]. In recent years, an improved genetic understanding of both common and rare diseases, collectively associated with mutations refl ecting immune system perturbations—ranging from the thymus, to B and T cells, to T regulatory cells—has vindicated the autoimmunity paradigm [3] (Table 1).