Immunomodulatory effect of extracorporeal photopheresis after successful treatment of resistant renal allograft rejection

Background: Acute renal allograft rejection contributes to patient morbidit y. Standard immunosuppressives are only partially effective and have signif icant side effects. Extracorporeal photopheresis (ECP) has been effective i n reversing the acute rejection process. T cell cytokine expression is impl icated in rejection and tolerance but actual changes in the cytokine profil e of ECP-treated individuals have not been documented. Methods: ECP was administered to a patient with acute renal allograft rejec tion resistant to other immunosuppressives. Enzyme-linked immunosorbent spo t (ELISPOT) assay was performed to determine the frequency of mitogen-induc ed cytokine-producing cells before and after ECP. Results: ECP resulted in resolution of rejection; serum creatinine concentr ation fell from 7.1 to 2.2 mg/dl; ELISPOT revealed a three-fold increase in the frequency of IL-5 producing cells; IFN-gamma :IL-5 ratio shifted from 2.73 pre-treatment to 1.01 post-treatment, Conclusion: Effective therapy of acute allograft rejection with ECP alters the peripheral blood cytokine profile towards "type 2" cytokines, suggestin g that alteration of T cell cytokine profiles may contribute to the resolut ion of the process.