Duquesnoy René J
Division of Transplant Pathology, Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA.
Curr Opin Organ Transplant. 2014 Aug;19(4):428-35. doi: 10.1097/MOT.0000000000000100.
Human leukocyte antigen (HLA) antibodies are now recognized as being specific for epitopes which can be defined structurally with amino acid differences between HLA alleles. This article addresses two general perspectives of HLA epitopes namely antigenicity, that is their reactivity with antibody and immunogenicity, that is their ability of eliciting an antibody response.
Single-antigen bead assays have shown that HLA antibodies recognize epitopes that are equivalent to eplets or corresponding to eplets paired with other residue configurations. There is now a website-based Registry of Antibody-Defined HLA Epitopes (http://www.epregistry.com.br). Residue differences within eplet-defined structural epitopes may also explain technique-dependent variations in antibody reactivity determined in Ig-binding, C1q-binding and lymphocytotoxicity assays.HLA antibody responses correlate with the numbers of eplets on mismatched HLA antigens, and the recently proposed nonself-self paradigm of epitope immunogenicity may explain the production of epitope-specific antibodies.
These findings support the usefulness of HLA matching at the epitope level, including the identification of acceptable mismatches for sensitized patients and permissible mismatching for nonsensitized patients aimed to reduce HLA antibody responses.
人类白细胞抗原（HLA）抗体现在被认为对表位具有特异性，这些表位可以通过HLA等位基因之间的氨基酸差异在结构上进行定义。本文探讨了HLA表位的两个一般观点，即抗原性，也就是它们与抗体的反应性，以及免疫原性，即它们引发抗体反应的能力。
单抗原珠试验表明，HLA抗体识别的表位等同于表位或与其他残基构型配对的表位。现在有一个基于网站的抗体定义的HLA表位登记处（http://www.epregistry.com.br）。表位定义的结构表位内的残基差异也可能解释在Ig结合、C1q结合和淋巴细胞毒性试验中测定的抗体反应性的技术依赖性变化。HLA抗体反应与不匹配的HLA抗原上的表位数量相关，最近提出的表位免疫原性的非自身-自身范式可能解释表位特异性抗体的产生。
这些发现支持在表位水平进行HLA匹配的有用性，包括识别致敏患者可接受的不匹配以及未致敏患者允许的不匹配，旨在减少HLA抗体反应。
