 IdeS is an IgG-degrading enzyme of S.pyogenes that cleaves all four human subclasses of IgG with strict specificity. Alloantibodies are a major deterrent to access to and success of life-saving organ transplants. We hypothesize that the use of IdeS pre-transplant in HS patients will represent a more robust and complete technique to eliminate DSA from the sera of HS patients. A single dose administration of IdeS in the pre-operative period to HS patients with positive DSAs and flow cytometry crossmatches will durably eliminate circulating DSAs, allow transplantation to occur without ABMR and, in conjunction with standard desensitization therapy, result in a durable suppression of DSA levels thus eliminating the risk for ABMR. 