Comparison of Characteristics of De Novo Donor-Specific Anti-HLA Antibodies (dnDSAs) in Living-Donor Lobar Lung Transplantation and Deceased-Donor Lung Transplantation

Purpose The impact of de novo donor-specific anti-HLA antibodies (dnDSAs) on patients after lung transplantation remains controversial. We investigated various characteristics of dnDSAs such as timing of initial dnDSA detection and type of HLA classes and compared them between living-donor lobar lung transplants (LDLLTs) and deceased-donor lung transplants (DDLTs) at a single institution in Japan. Methods We performed 92 LDLLTs and 129 DDLTs between 2008 and 2019. Patients, in whom anti-HLA antibodies were measured both pre- and post-operatively, were included in this study. Patients who had pre-formed DSA and patients undergoing re-transplantation were excluded. Results This retrospective study included 79 recipients undergoing LDLLT and 109 recipients undergoing DDLT. In total, 29 patients (15.8%) had dnDSAs. They consisted of 6 LDLLT recipients and 23 DDLT recipients. In LDLLT, cumulative incidence of dnDSA detection was 4.2%, 4.2% and 6.3% at 1, 3 and 5 years, respectively. On the other hand, in DDLT, cumulative incidence of dnDSA detection was 18.1%, 21.6% and 23.7% at 1, 3 and 5 years, respectively (p=0.002, Figure 1). Class I dnDSAs were more frequently detected in DDLT recipients (10.1%) than in LDLLT recipients (1.3%, p=0.015), while the incidence of class II dnDSAs were comparable between two groups (12.8% in DDLT and 7.6% in LDLLT, p=0.34). Conclusion We found that dnDSAs were significantly more frequently detected in DDLT than in LDLLT. Types of dnDSA seemed different between LDLLT and DDLT.