Dendritic cells/chimerism/alleviation of chronic allograft rejection.
Chronic rejection (CR) is the major obstacle of long-term successful organ transplantation. Using a recently developed rat model of CR, we found that heart allografts susceptible to development of CR showed an early (< 10 days) dramatic disappearance of donor MHC class II+ cells, including ED2+ tissue macrophages, and an influx of recipient ED1+ macrophages intermixed with small numbers of recipient ED2+ and OX62+ cells. In contrast, donor MHC class II+ cells persisted in allografts resistant to CR with a small influx of recipient macrophages. MHC class II+ cells function as potent modulators of the immune system and may mediate both stimulatory and tolerogenic immune reactions after transplantation. Persistence of donor MHC class II+ antigen-presenting cells (APC) in CR-free graft acceptance suggests that transplantation tolerance is an active immune response requiring antigen presentation to the recipient immune system in the proper context by dendritic cells and other APC.
Murase
N
N
Thomas E. Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh Medical Center, Pennsylvania, USA. murase+@pitt.edu
Ichikawa
N
N
Ye
Q
Q
Chun
H J
HJ
Okuda
T
T
Demetris
A J
AJ
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D003713:Dendritic Cells / Q000276:immunology*; D004195:Disease Models, Animal; D006084:Graft Rejection / Q000276:immunology*; D016027:Heart Transplantation / Q000276:immunology; D016130:Immunophenotyping; D051381:Rats; D018183:Transplantation Chimera / Q000276:immunology*; D014184:Transplantation, Homologous / Q000276:immunology*