| |
|
| |
|
|
ProjectsHLA DictionaryA Summary of HLA Alleles and their Associated HLA AntigensReport of the WMDA Working Group on the HLA Dictionary Ieke Schreuder on behalf of Marcelo Fernandez-Vina, Rhonda Holdsworth, Carolyn Hurley, Marie Lau, Steven Marsh, Martin Maiers, Harriet Noreen and Michelle Setterholm The aim of the Working Group is to prepare regular updates of the HLA Dictionary. The HLA Dictionary presents serologic equivalents for HLA alleles. Recently the HLA Dictionary 2004 has been published (Tissue Antigens 2005, 65: 1-55, Human Immunology 2005, 66:170-210, International Journal of Immunogenetics 2005, 32:19-69). In the Dictionary 2004, equivalents for almost all HLA-A, -B, and HLA-DRB1 alleles were included, as well as equivalents for a number of HLA-Cw, DRB3, DRB4, DRB5 and DQB1 alleles. The Working Group published the first Dictionary in 1997 and prepared updates in 1999, 2001 and 2004. The data summarize information obtained by the WHO Nomenclature Committee for Factors of the HLA System, the International Cell Exchange (UCLA), the US National Marrow Donor Program (NMDP) and individual laboratories. The latest update of 2004 includes new significant findings, obtained by the efforts of the serologic working group component of the 13 th International Histocompatibility Workshop. One of the group’s aims, to find serological equivalents for as many as possible rare and ill defined alleles, was well met, with over 900 cell samples collected world-wide, which included more than 150 rare and newly identified alleles. The Dictionary 2004 update also includes a listing of predicted equivalents as obtained by Neural Network analyses, which are especially helpful for alleles with little or no serological details. The recommended serologic equivalents are presented as expert assigned types. The tables include remarks for alleles, which are or may be expressed as antigens with serologic reaction patterns that differ from the well-established HLA specificities. The equivalents provided in the Dictionary are used for guiding searches for unrelated haematopoietic stem cell donors in which patients and/or potential donors are typed by either serology or DNA-based methods. The equivalents also serve typing and matching procedures for organ transplant programs where HLA typings from donors and from recipients on waiting lists represent mixtures of serologic and molecular typings. Moreover, although the Dictionary does not provide well-established allele frequencies, it at least provides an indication about the occurrence of certain alleles. Copies of the Dictionary can be reached via: www.worldmarrow.org, www.anthonynolan.org.uk/HIG/nomen/dictionary/dictionary2004.html and www.ebi.ac.uk/imgt/hla/dictionary.html. The latter site provides also a search tool by which the tables can be consulted for alleles, expert assigned types as well as WHO assigned types (see image below). The Working Group is very happy with this important facility. Another goal of the Working Group is to provide more frequent updates to the information. This information can then be utilized by hematopoietic stem cell registries to routinely update their matching algorithms and to support other search and matching activities.
Anyone who can provide serological equivalents for rare or ill-defined alleles is welcome to submit typing results to the Working Group. Contact: Ieke Schreuder |
