title: Heterogeneity of human alpha-fetoprotein as revealed by isoelectric focusing in urea-containing gels.
abstract: The heterogeneity of human alpha-fetoprotein has been studied by analytical isoelectric focusing in polyacrylamide gel slabs in the presence of 8 M urea. Six major isoelectric variants could be identified over a pH range of 6.0--6.2. Verification of their identity was achieved by crossed immunoelectrophoresis into agarose gel containing monospecific antiserum to human alpha-fetoprotein. Complete desialylation of the protein did not abolish the heterogeneity; a complex pattern of major alpha-fetoprotein bands persisted over a more alkaline pH range. We have been able to correlate the pattern of alpha-fetoprotein heterogeneity seen following extended agarose gel electrophoresis with that obtained during isoelectric focusing in the presence of urea. The quantity of certain alpha-fetoprotein charge isomers in various alpha-fetoprotein isolates may be important in considering certain biological functions of this protein.
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel; D014644:Genetic Variation; D006801:Humans; D007123:Immunoelectrophoresis, Two-Dimensional; D007525:Isoelectric Focusing; D008113:Liver Neoplasms / Q000032:analysis; D008970:Molecular Weight; D014508:Urea; D000509:alpha-Fetoproteins
chemical_list: D000509:alpha-Fetoproteins; D014508:Urea