Correlation between the cystic fibrosis protein detected by isoelectric focusing and a protein of 12 kDa detected by SDS-polyacrylamide gel electrophoresis.
We have studied both by isoelectric focusing and polyacrylamide gel electrophoresis in the presence of SDS, sera of individuals homozygous (25) and heterozygous (26) for cystic fibrosis and compared them to controls (13). As in our first study [1], the protein with a pI value of 8.4 called 'cystic fibrosis protein' or CFP, was found in about 70% of homozygous and carriers and in 15% of controls. When the same sera were analysed by polyacrylamide gel electrophoresis in the presence of SDS and after staining with Coomassie Blue, an additional protein with a molecular weight close to 12,000 (P12) was present in most of the sera containing CFP, suggesting a close relationship between the two proteins. By increasing the sensitivity of staining by using silver nitrate, P12 was detected with variable intensity in almost all sera of homozygotes and heterozygotes and at the level of traces in all normal sera. These data suggest that P12, like CFP, would be a normal serum protein quantitatively increased in affected subjects.
D000328:Adult; D001798:Blood Proteins / Q000032:analysis*; D040501:Calgranulin A; D003550:Cystic Fibrosis / Q000097:blood* / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D005838:Genotype; D006801:Humans; D007525:Isoelectric Focusing; D012834:Silver; D012967:Sodium Dodecyl Sulfate; D013194:Staining and Labeling
D001798:Blood Proteins; D040501:Calgranulin A; C026422:cystic fibrosis serum factor; D012967:Sodium Dodecyl Sulfate; D012834:Silver