Humoral immunity and antibody-mediated rejection in solid organ transplantation

► HLA sensitization can be a barrier to successful transplantation of all solid organs. ► ABO and HLA incompatible transplants now possible after antibody depletion protocols. ► Knowing antibody strength helps stratify risk of antibody-mediated rejection. ► Lag in isohemagglutinin development offers unique window for neonatal heart transplant. ► Complex and layered humoral responses preclude the clinical application of xenotransplantation.