Cookies on this website
We use cookies to ensure that we give you the best experience on our website. If you click 'Continue' we'll assume that you are happy to receive all cookies and you won't see this message again. Click 'Find out more' for information on how to change your cookie settings.

Reconstitution of the peripheral T-cell compartment is a critical aspect for the success of bone marrow transplantation and is also dependent on the reestablishment of normal thymic structure and function. Graft-versus-host disease (GVHD), however, exacerbates posttransplant immunodeficiency through a deleterious effect on thymic function. To investigate the mechanisms of GVHD-mediated thymic disease, 2 murine parent-->F(1 )transplantation models of acute and chronic GVHD, respectively, were studied. Acute GVHD was associated with changes in thymic architecture and a reduction in cellularity mainly because of the decrease in CD4(+)CD8(+), or double-positive (DP) thymocytes, to less than 15% of values found in mice without GVHD. Simultaneously, mature donor-derived T cells expanded in the confines of the allogeneic thymic microenvironment, leading to local inflammation. Through analysis of in vivo cell proliferation, we demonstrated that the ensuing depletion of DP thymocytes was secondary to a decreased commitment of resident pro-T and pre-T cells to enter the cell cycle. Moreover, DP cells themselves showed altered proliferative capacities in the presence of acute GVHD. These findings suggested that thymic atrophy in acute GVHD is effected by impaired cellular proliferation of immature host thymocytes and that the failure of these cells to enter the cell cycle is dependent on an interferon (IFN)-gamma-driven immune response. In contrast, interleukin-4-driven chronic GVHD was not accompanied by a sustained thymic infiltration of donor T cells. Consequently, there was a lack of apparent structural changes, a restricted in situ transcription of inflammatory cytokines, and a virtually unchanged cell cycle progression in vivo.

Type

Journal article

Journal

Blood

Publication Date

01/07/2000

Volume

96

Pages

347 - 354

Keywords

Animals, Atrophy, Cell Cycle, Crosses, Genetic, Female, Graft vs Host Disease, Lymphocyte Transfusion, Mice, Mice, Inbred C57BL, Mice, Inbred DBA, Mice, Inbred Strains, T-Lymphocytes, Thymus Gland, Transplantation Chimera, Transplantation, Heterotopic, Transplantation, Homologous