Secondary Delayed-Type Hypersensitivity to Sheep Red Blood Cells and Minor Histocompatibility Antigens in Mice: Transfer of Memory by Recirculating Thoracic Duct Lymphocytes

Abstract

Secondary delayed-type hypersensitivity (DTH) in mice to sheep red blood cells (SRBC) and minor histocompatibility (H) antigens is dependent on long-lived memory T cells. In this paper we investigated whether these memory T cells recirculate. It was shown that late phase «immune» thoracic duct lymphocytes (TDL) from mice which were immunized with SRBC or non-H-2-incompatible spleen cells several weeks previously could adoptively transfer secondary DTH to these antigens. Passing the immune TDL through intermediate recipients demonstrated that these SRBC- or minor H-antigen-reactive memory T cells recirculate from blood to lymph. In contrast to mice immunized with minor H antigens, no secondary type DTH reactivity could be demonstrated in mice immunized with H-2-incompatible spleen cells. Also, after adoptive transfer of TDL from mice immunized with H-2 alloantigens, it was impossible to demonstrate an accelerated DTH reactivity.