DONOR ANTIGEN IS NECESSARY FOR THE PREVENTION OF CHRONIC REJECTION IN CTLA4IG-TREATED MURINE CARDIAC ALLOGRAFT RECIPIENTS1,2

Abstract

Donor cells are required to synergize with CTLA4Ig and prevent late cardiac allograft loss in the murine system. The fact that pretreatment of the donor cells alone is not effective suggests a role for antigen presentation by recipient antigen-presenting cells in the initiation of rejection. As lethal irradiation of the donor cells does not affect their ability to promote long-term engraftment, our data suggest that long-term microchimerism is not required to prevent chronic rejection in this model.