HLA membrane antigens: sequencing by intrinsic radioactivity.

Radiochemical sequence data are presented for the amino termini of mixed HLA antigens A1 and B8 isolated from a human lymphoblastoid cell line. Cells were labeled intrinsically in small-scale tissue culture with 14C-labeled amino acids and [14C]pyruvate. The specific activities obtained were sufficiently high and uniform to permit direct radiochemical sequencing of the antigens. HLA antigens were isolated by adsorption to a solid-phase anti-beta2-microglobulin immunoadsorbent followed by electrophoresis. The method should be generally applicable and useful for sequencing all parts of the molecule.