An improved biochemical method for the analysis of HLA-class I antigens. Definition of new HLA-class I subtypes.

A simple method is described for the biochemical analysis of HLA class I antigens. It is a modification of a previously published procedure for one-dimensional isoelectric focusing (1D-IEF), giving improved resolution and offering larger sample capacity. One million viable cells suffice for analysis, and no more than 25 muCi of radioisotope (35S-methionine) are required. The usefulness of the method is illustrated by the characterization of a total of four biochemically distinct subtypes of HLA-B27, three subtypes of HLA-A24, two subtypes of HLA-A11, three subtypes of HLA-A2, two subtypes of HLA-Bw60, two subtypes of HLA-Bw62, and four subtypes of HLA-B35 in a panel of 24 cells selected for the expression of HLA-B27. We envision that this technique will allow a rigorous classification of HLA-A,B antigens into novel subtypes. Populations of distinct ethnic origin are especially of interest in this regard. This technique might also be used as an additional criterion for the official classification of HLA-A,B antigens.