LUNG REJECTION OCCURS IN LUNG-TRANSPLANT RECIPIENTS WITH BLOOD CHIMERISM

Background. It has been postulated that chimerism after transplantatio n might promote graft acceptance. In the present study, we prospective ly assessed blood chimerism in 10 lung transplant recipients during th e first posttransplant year and investigated whether chimerism was ass ociated with an immunologically stable situation of the graft. Methods . The recipients' peripheral blood mononuclear cells were obtained bef ore transplantation and at various time points during the first postop erative year. Donor cells were detected using nested polymerase chain reaction amplification of a donor-specific HLA-DRB1 allele. Clinical g raft acceptance was determined by the number of rejection episodes. Re sults. The incidence of blood chimerism was high during the first 3 po stoperative months and then decreased over time. All patients experien ced at least one acute rejection episode, and three patients developed chronic rejection. Conclusion. We, thus, conclude that rejection of t he lung allograft may occur in the presence of blood chimerism.