The Seventh Histocompatibility Workshop
The Seventh Histocompatibility Workshop, organized by Walter Bodmer and held at Oxford in September of 1977, carried forward a number of investigations: the serological study of the newly-described Ia (Immune-associated) determinants that were present on B cells but not on T cells, the relationship between the Ia specificities and Dw determinants defined by MLR and Dw homozygous typing cell (HTC) testing, the continued study of specificities belonging to the previously-defined HLA-A, B and C loci, and a study of a limited number of diseases to define their relationship with HLA-A, B, Dw and/or Ia specificities. For this workshop, the world was divided into 20 regions, each with its own regional officer, since there were too many participating laboratories to permit a central organization or data analysis. A total of 150 laboratories participated, studying 360 antisera, a panel of 13,000 lymphocytes covering all of the world’s major racial groups, and 54 homozygous typing cells. Based on workshop results, the HLA-DR locus, later shown to be part of the loosely-defined “Ia” antigen system, was officially defined, and a total of 26 new specificities were assigned WHO designations. In addition, evidence of a second Ia locus, termed MT by some laboratories and MB by others, began to emerge from this workshop. A total of 19 new HLA specificities were given WHO designations following the workshop, including the first seven antigens of the HLA-DR locus (DR1-DR7).
Reference: Bodmer WF, Batchelor JR, Bodmer JG, Festenstein H, Morris PJ, eds. Histocompatibility Testing 1977. Copenhagen: Munksgaard, 1978.