Anti-immunoglobulin as an adjunct in producing long-term antigen-specific allograft survival. Organ localization of immune complexes.

Heterologous anti-immunoglobulin is a potent immunosuppressive agent that prolongs H-2- and H-3-incompatible skin graft survival. In conjunction with antithymocyte serum, anti-immunoglobulin promotes greater graft life than either antiserum used alone, without evidence of toxicity to recipient animals. Combination treatment with anti-immunoglobulin, antithymocyte serum, and donor spleen cells produces long-term allograft survival to the lifetime of the host and can result in antigen-specific immune unresponsiveness of sufficient strength to permit acceptance of a second-set graft. Anti-immunoglobulin complexes formed in treated mice appear to be localized primarily in the lymphatic reticuloendothelial system.