Transfusion specific alloimmune responses following blood transfusion pre-kidney transplantation.

Abstract

It is widely accepted that blood transfusions can cause allosensitisation, but it is often reported that new HLA antibodies are non-specific and transient. This study explores the effect of blood transfusion on allosensitisation in waitlisted transplant patients including the development of transfusion specific antibodies (TSAs), whilst they remain on the waiting list and longitudinally following subsequent transplantation. A total of 105 blood donors of transfusions received by 50 patients on the transplant waiting list were HLA typed. De novo HLA antibodies developed in 62% of patients following transfusion, with 34% of patients having at least one TSA. TSAs developed in 23% of patients with no circulating HLA antibodies at the time of transfusion and in 50% of patients with circulating HLA antibodies. This was associated with an average increase in calculated reaction frequency of 16.4%. Of the 34 patients who were transplanted the majority received a kidney with at least 1 shared HLA specificity with a transfusion donor. After transplantation 14.7% had a newly detected TSA within 3 months. These patients had higher rates of rejection, specifically antibody mediated rejection, at 3 years. The use of HLA-selected blood for waitlisted patients, where transfusion is unavoidable, could therefore improve transplant outcomes.