ABSTRACT
Cod fish is one of the foods most frequently involved in allergy. Only the cod allergen Gad c I, a 12.3 kDa parvalbumin, has been purified and characterized. Recently, we have detected allergen bands which have not previously been described, in particular a 41 kDa protein, by Western-blot. In the present work, this protein has been purified from a crude cod extract by ammonium sulfate fractionation, hydroxyapatite chromatography and preparative electrophoresis; a single band with an Mr of 41 x 10(3) was found in silver-stained sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The amino acid composition and the isoelectric point of the protein were determined. The purified protein (p41) was shown to bind specifically to reaginic IgE from sera of cod-allergic individuals and to a monoclonal anti-parvalbumin which recognizes specifically the first calcium binding site of parvalbumins. p41 may therefore contain a calcium binding site corresponding to an IgE-epitope similar to that of Gad c I.
Subject(s)
Allergens/isolation & purification , Fishes , Proteins/isolation & purification , Amino Acids/analysis , Ammonium Sulfate , Animals , Chromatography , Durapatite , Electrophoresis , Electrophoresis, Polyacrylamide Gel , Food Hypersensitivity , Fractional Precipitation , Hydrogen-Ion Concentration , Molecular Weight , Proteins/chemistry , Proteins/immunology , Silver StainingABSTRACT
The impact of the major interferents (hemolysis, bilirubin, turbidity), on the quality of biochemical tests, was evaluated on multiparametric analysers (CL 7200 Shimadzu, Japan/Ciba-Corning, France; AU 5231 and AU 5223 Olympus, Japan/bioMérieux, France), according to the SFBC instructions. Interferences were detected in 33 cases upon 165 tests realized, that is to say 20% of the performed analysis. Turbidity was the most frequent cause of interference (7.8%), followed by hemolysis (8.5%) and bilirubin (3.6%). The use of a sample blank, a bireagent, the change of reagent, the change of the secondary wavelength or the modification of the measurement times, allowed us to reduce more than 80% of the interferences. Only three interferences remained: hemolysis upon the measurement of TGO and potassium, and bilirubin upon the measurement of creatinine. For these parameters, a suitable note using the Olympus factors (semi quantitative expression of the importance of the three interferents) is reported on the answer sheet.
