Isolation of patient-related antigens from allergen extracts by means of protein A-sepharose-patient IgG1,2,4 bio-affinity chromatography.

A method is described for bio-affinity purification of patient-specific IgG reactive antigens by using protein A-sepharose allergic patient serum and the corresponding antigen/allergen extract. The optimal conditions for each step have been determined and it is shown that the non-specific binding of both serum proteins and antigens can be kept at very low levels by a high ionic strength. The specificity of the reaction has been shown by biospecific elution of 125I-labelled antigens by non-labelled antigens and also by comparison of the amount of antigen bound by sera from hyposensitized patients with that from non-atopic individuals. It is suggested that the isolated antigen-IgG-immune complexes could be used for a specific and active immunotherapy.