The mechanisms of systemic autoimmune disease are poorly understood and available therapies often lead to immunosuppressive conditions. We describe here a new model of autoantigen-specific immunotherapy based on the sites of autoantigen presentation in systemic autoimmune disease. Nucleosomes are one of the well-characterized autoantigens. We found relative splenic localization of the stimulative capacity for nucleosome-specific T cells in (NZB x NZW)F(1) (NZB/W F(1)) lupus-prone mice. Splenic dendritic cells (DCs) from NZB/W F(1) mice spontaneously stimulate nucleosome-specific T cells to a much greater degree than both DCs from normal mice and DCs from the lymph nodes of NZB/W F(1) mice. This leads to a strategy for the local delivery of therapeutic molecules using autoantigen-specific T cells. Nucleosome-specific regulatory T cells engineered by triple gene transfer (TCR-alpha, TCR-beta, and CTLA4Ig) accumulated in the spleen and suppressed the related pathogenic autoantibody production. Nephritis was drastically suppressed without impairing the T cell-dependent humoral immune responses. Thus, autoantigen-specific regulatory T cells engineered by multiple gene transfer is a promising strategy for treating autoimmune diseases.