Origins of the first HLA specificities.

Following the discovery of the first histocompatibility antigen "MAC" in 1958, numerous independent laboratories began identifying HLA specificities with allo-antibodies. During the span of about a decade, 1958-1970, virtually all of the common HLA-A and HLA-B antigens were identified by various names and presented at the International Histocompatibility Workshops by means of different serological methods. Because many of the independently discovered specificities were found to be reactive to similar determinants on lymphocytes, it became necessary to classify the antigens by means of a standard method. The micro lymphocytotoxicity test was chosen to be the basis for future antigen testing, thereby allowing the various laboratories to confidently exchange sera. At the 1968 WHO Nomenclature meeting, the naming of the first antigen ultimately gave rise to the designation "HLA" in the human MHC Class I antigen system. This paper looks back upon the origins of the early serologically identified HLA specificities and their respective founders.