The isolation and properties of an allergen extracted from Ascaris suum

An allergen has been isolated from the whole-worm extract of the nematode Ascaris suum by gel chromatography and ion exchange chromatography. The allergen was detected by its activity in the homologous rat passive cutaneous anaphylaxis test. Sequential allergen challenge of a multispecific rat reaginic antiserum showed that the allergen preparation was not contaminated by other allergens which were present in the whole-worm extract. The homogeneity of the preparation was further demonstrated by immunoelectrophoresis, polyacrylamide gel electrophoresis, thin layer gel filtration and ultracentrifugation studies. The results obtained indicated that the allergen had a molecular weight close to 14,000 and that it could be regarded as a compact and approximately spherical molecule. [Continues.]