Highly purified papain-solubilized HL-A antigens contain beta2-microglobulin.
HL-A antigens comprising 11 different antigenic specificities were isolated after papain solubilization of spleen-cell membrane constituents. During the entire purification procedure, beta(2)-microglobulin appeared together with the HL-A antigens. The highly purified antigens were composed of two polypeptide chains. The large subunit carried the antigenic specificity whereas the small polypeptide chain was very similar, if not identical, to beta(2)-microglobulin. The two HL-A antigen polypeptide chains were held together by noncovalent interactions only, and beta(2)-microglobulin, isolated from urine, could replace the small subunit in forming a complex with the large polypeptide chain. The topographical relationship in the cell membrane between beta(2)-microglobulin and the large HL-A antigen polypeptide chain is unknown. The two polypeptide chains may be fortuitously bound as a result of the solubilization procedure.
D000918:Antibody Specificity; D000936:Antigen-Antibody Complex; D000937:Antigen-Antibody Reactions; D002462:Cell Membrane / Q000276:immunology; D002848:Chromatography, DEAE-Cellulose; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes; D005260:Female; D005916:Globulins / Q000302:isolation & purification*; D006649:Histocompatibility Antigens / Q000032:analysis* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008970:Molecular Weight; D010206:Papain; D010455:Peptides / Q000302:isolation & purification; D011863:Radioimmunoassay; D013154:Spleen / Q000276:immunology
D000936:Antigen-Antibody Complex; D000939:Epitopes; D005916:Globulins; D006649:Histocompatibility Antigens; D010455:Peptides; D010206:Papain