Preformed donor-directed anti-HLA-DP antibodies may be an impediment to successful kidney transplantation.

Recent reports have suggested an association of antiDP antibodies with allograft rejection and graft loss, in both primary kidney transplant recipients and in re-grafts [1–3]. However, in most cases, it is difficult to separate the effects of anti-HLA-DP antibodies from other anti-HLA class I and class II antibodies. Among non-conserved haplotypes, HLA-DP allele mismatches occur despite matching for HLA class I and class II loci, because of the lack of linkage disequilibrium between DP and other HLA loci [4]