Higher relapse and worse overall survival in recipients with CTLA-4 AA genotype of rs231775 following single-unit cord blood transplantation in adults

We retrospectively investigated the impact of CTLA-4 polymorphism on outcomes for adult patients who received single-unit cord blood transplantation (CBT) at our institution. CTLA-4 genotyping was performed using real-time polymerase chain reaction with the TaqMan^® SNP genotyping assay for rs231775. This study included 143 recipient-donor pairs. The multivariate analysis showed that recipient rs231775 AA was associated with worse overall survival (OS) (hazard ratio [HR], 2.92; p = 0.008) and a higher relapse rate (HR, 4.79; p = 0.002), but donor rs231775 was not. The rs231775 polymorphism in recipients and donors did not affect non-relapse mortality, hematopoietic recovery, or acute and chronic graft-versus-host disease. The beneficial effects of rs231775 GG+GA recipients on OS and relapse were notable in subgroups of patients with high-risk disease status and those with myeloid diseases. The polymorphism of CTLA-4 rs231775in recipients might be associated with the clinical outcomes of single-unit CBT.