Role of the passive apoptotic pathway in graft-versus-host disease. J Immunol 2002 Aug 01;169(3):1626-33
Date
07/23/2002Pubmed ID
12133993DOI
10.4049/jimmunol.169.3.1626Scopus ID
2-s2.0-0036681957 (requires institutional sign-in at Scopus site) 14 CitationsAbstract
Donor T cells have been shown to undergo apoptosis during graft-vs-host disease (GVHD). Although active apoptosis mediated through Fas/Fas ligand interactions has been implicated in GVHD, little is known about the role of the passive apoptotic pathway. To examine this question, we compared the ability of normal donor T cells and T cells overexpressing the antiapoptotic protein, Bcl-x(L), to mediate alloreactive responses in vitro and lethal GVHD in vivo. In standard MLCs, T cells that overexpressed Bcl-x(L) had significantly higher proliferative responses but no difference in cytokine phenotype. Overexpression of Bcl-x(L) prolonged survival of both resting and alloactivated CD4(+) and CD8(+) T cells as assessed by quantitative flow cytometry, accounting for the higher proliferative responses. Analysis of engraftment in murine transplantation experiments demonstrated an increase in donor T cell chimerism in animals transplanted with Bcl-x(L) T cells, suggesting that overexpression of Bcl-x(L) prolonged T cell survival in vivo as well. Notably, transplantation of Bcl-x(L) T cells into nonirradiated F(1) recipients also significantly exacerbated GVHD as assessed by mortality and pathological damage in the gastrointestinal tract. However, when mice were irradiated no difference in GVHD mortality was observed between animals transplanted with wild-type and Bcl-x(L) T cells. These data demonstrate that the passive apoptotic pathway plays a role in the homeostatic survival of transplanted donor T cells. Moreover, the susceptibility of donor T cells to undergo passive apoptosis is a significant factor in determining GVHD severity under noninflammatory but not inflammatory conditions.
Author List
Drobyski WR, Komorowski R, Logan B, Gendelman MAuthor
William R. Drobyski MD Professor in the Medicine department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsApoptosis
Bone Marrow Transplantation
Cytokines
Graft vs Host Disease
Isoantigens
Lymphocyte Activation
Mice
Mice, Inbred C57BL
Proto-Oncogene Proteins c-bcl-2
T-Lymphocytes
Transplantation Chimera
Transplantation Conditioning
bcl-X Protein