Outcome of Extracorporeal Photopheresis as Add-On Therapy in Patients for Antibody-Mediated Rejection after Lung Transplantation

Purpose The diagnosis and treatment of antibody-mediated rejection (AMR) after LTx has gained increasing recognition within the transplant community. Extracorporeal photopheresis (ECP) modulates various pathways of the immune system and is currently used to treat CLAD. In AMR, adding ECP to established AMR treatments could potentially prevent rebound of DSA. This study aimed to analyze the role of ECP as adjunct treatment of AMR. Methods Patients who developed antibody-mediated rejection between 2009 and 2019 were included in this single-center retrospective analysis. The following parameters were evaluated: DSAs, C4d deposition and lung histology. Results A total of 39 patients developed clinical AMR during follow-up. Nineteen (48%) patients had positive DSA against HLA Class I and eighteen (46%) HLA Class II. Median time to diagnosis of AMR was 180 days (IQR: 2-2477). First line treatment was immunoadsorption (IA) in 34 (87%) patients, intravenous immunoglobulins with concomitant immunoadsorption in 3 (8%) patients and in 2 cases ATG. Twenty (51%) patients primarily treated with IA and the two patients treated with ATG received ECP. Among the patients treated with ECP, 12 had DSA against HLA Class I and 13 against HLA Class II. ECP treatment was initially performed twice a week. After stabilization of lung function and improvement of clinical situation, ECP was then performed once a month for a minimum of 6 months. Median length of treatment was 12 months. Patients who received ECP after first line treatment had 1-year survival rate of 62% compared to 27% of other AMR patients. In all patients treated with IA followed by ECP, DSA disappeared or MFI reduced below our institutional threshold of 5000. Conclusion Extracorporeal photopheresis is associated with a reduction of de novo DSA after antibody-mediated rejection. Prospective studies are necessary to confirm the beneficial effect of ECP as an add-on therapy after AMR.