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

BACKGROUND: Acute renal allograft rejection contributes to patient morbidity. Standard immunosuppressives are only partially effective and have significant side effects. Extracorporeal photopheresis (ECP) has been effective in reversing the acute rejection process. T cell cytokine expression is implicated in rejection and tolerance but actual changes in the cytokine profile of ECP-treated individuals have not been documented. METHODS: ECP was administered to a patient with acute renal allograft rejection resistant to other immunosuppressives. Enzyme-linked immunosorbent spot (ELISPOT) assay was performed to determine the frequency of mitogen-induced cytokine-producing cells before and after ECP. RESULTS: ECP resulted in resolution of rejection; serum creatinine concentration 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, suggesting that alteration of T cell cytokine profiles may contribute to the resolution of the process.