Predicting alloreactivity in transplantation

Human leukocyte antigen (hla) mismatching leads to severe complications after solid-organ transplantation and hematopoietic stem-cell transplantation. the alloreactive responses underlying the posttransplantation complications include both direct recognition of allogeneic hla by hla-specific alloantibodies and t cells and indirect t-cell recognition. however,the immunogenicity of hla mismatches is highly variable; some hla mismatches lead to severe clinical b-cell- and t-cell-mediated alloreactivity,whereas others are well tolerated. definition of the permissibility of hla mismatches prior to transplantation allows selection of donor-recipient combinations that will have a reduced chance to develop deleterious host-versus-graft responses after solid-organ transplantation and graft-versus-host responses after hematopoietic stem-cell transplantation. therefore,several methods have been developed to predict permissible hla-mismatch combinations. in this review we aim to give a comprehensive overview about the current knowledge regarding hla-directed alloreactivity and several developed in vitro and in silico tools that aim to predict direct and indirect alloreactivity. © 2014 kirsten geneugelijk et al.