P043 HLA-DP donor specific antibodies associated with antibody mediated rejection and poor allograft survival following lung transplant

Objective It has been widely recognized that donor specific antibody (DSA) is correlated with antibody-mediated rejection (AMR) and graft loss in solid organ transplant (Tx). However, the impact of HLA-DP DSA in Tx has been poorly understood, especially in lung Tx. Here we analyze the association of DP DSA with lung Tx clinical outcomes. Methods This study retrospectively analyzed 213 individuals selected from 720 recipients who underwent lung Tx at Cleveland Clinic from 2008 to 2015. 213 patients were analyzed in three groups: G1- without HLA antibody (n = 144), G2- with DP antibodies (n = 69), G3- with DP DSAs among the individuals in G2 (n = 20). Two year graft survival (GS), AMR, acute cellular rejection (ACR), and bronchiolitis obliterans syndrome (BOS), were recorded as deleterious clinical outcomes. Luminex single antigen assay was used for HLA antibody testing. Results DP antibodies were detected in 10% (69/720) lung Tx patients. DP DSAs were identified in 29% (20/69) of the patients with DP antibodies. De novo DP DSA was identified in 90% (18/20) of the patients with DP DSAs. In G3, 15% (3/20) had other class I DSA, 35% (7/20) had other class II DSA, and 50% (10/20) had only DP DSAs. Compared to patients in G1, patients in G2 showed higher occurrence of AMR (p = 0.019), but there was no remarkable difference in 2 year graft survival, ACR, and BOS. A comparison between G1 and G3 showed that patients with DP DSAs (G3) presented with significantly more AMR and poor GS (p = 0.010 and 0.003 , respectively) than patients who had no HLA antibodies. However, ACR, and BOS were equivalent (Table 1a). There was higher incidence of AMR and lower rate of GS in patients with DP DSA combined with class I or class II than in patients who only had DP DSA (Table 1b). Download : Download high-res image (212KB) Download : Download full-size image Conclusion DP DSA is associated with negative impact following lung Tx by increasing the incidence of AMR and reducing GS. DP DSA combined with other HLA-DSAs demonstrates increased adverse clinical outcomes. This finding warrants further investigation with larger cohort studies.