P072 De novo anti-HLA-class II donor specific antibodies are associated with patient mortality after lung transplant failure

Aim The development of donor-specific HLA antibodies (DSA) after lung transplantation has been implicated in acute and chronic rejection. The diagnosis of lung antibody mediated rejection (AMR) is based upon histology, DSA testing and clinical assessment of graft function. Post-transplant DSA monitoring has become more and more common as a guide toward diagnosis and sometimes institution of AMR treatment. In this study, we aimed to assess DSA with biopsy surveillance and associate with patient mortality after lung transplant failure (MLTF). Methods We retrospectively selected 127 patients, transplanted between Jan, 2004 and July, 2015 whose DSA were tested for clinical indications post-transplantation. Protocol biopsies were performed for these patients at 1, 3, 6, 9, and 12-months after transplant for clinical suspicions. DSA were monitored using LabScreen single antigen bead assays. Biopsy HE however, no association was found for Class I DSA. No significant relationship between DSA and histological changes of AMR in lung transplant biopsies was found in this cohort. Conclusion HLA Class II DSA is associated with graft dysfunction and mortality in pulmonary transplant patients although we did not find the correlation with biopsy findings. Our study suggests that post-transplant protocol DSA surveillance may add value to assess allograft function and to treat graft rejection at the early stage.