[Recent advances in animal models of autoimmune disease]

Various autoimmune diseases can be induced in normal animals by simply manipulating the thymus/T cells. For example, elimination of CD25+CD4+ T cells, which constitute about 10% of peripheral CD4+ T cells of normal mice, leads to the development of various organ-specific autoimmune diseases, such as thyroiditis, gastritis, adrenalitis, insulitis, sialoadenitis, oophoritis, or orchitis. Reconstitution of CD25+CD4+ T cells prevents the autoimmune development. Elimination/reduction of CD25+CD4+ T cells induced by genetical manipulation of T-cell ontogeny or caused by environmental agents, such as virus infection, also causes similar autoimmune diseases in normal mice. These newly developed animal models of autoimmune disease will be useful for elucidating the mechanism of immunologic self-tolerance and pathogenetic mechanism of autoimmune disease.