Transplantation of Thymic Tissue into Patients With AIDS

Abstract
• Thymic epithelial fragments were transplanted into 15 patients in an advanced stage of the acquired immunodeficiency syndrome (AIDS). One patient was given interleukin 2 in addition to thymic tissue. We demonstrated the following: (1) Thymic epithelial fragments cultured before transplantation to remove T cells survived for months after transplantation in eight of 15 patients and seemed to be responsible for a partial, selective, but transient repopulation of the circulating T-cell pool. (2) The absolute number of T8 cells, but not T4 cells, increased three to four weeks after the procedure in eight of the 15 subjects. (3) This increase in T8 cells was associated with clinical improvement in some cases and increased T-cell responsiveness in vitro. (4) Thymic tissue transplantation as a single therapeutic maneuver is unlikely to reconstitute the immune system of patients with AIDS, but the potential of the approach, used in combination with agents that block replication of human T-cell lymphotropic virus type III, deserves further study. (Arch Intern Med1987;147:513-517)