The present invention relates to the treatment of a hypersensitivity immune response, such as allergic rhinitis or asthma, via bystander suppression by use of an antigen unrelated to the allergen triggering the hypersensitivity immune responsein an individual to be treated, wherein the antigen is obtainable from the source material comprising the 〝triggering〞 allergen.本發明關於藉由使用與引發被治療之個體的超敏性免疫反應之過敏原無關之抗原經由旁路抑制以治療超敏性免疫反應(諸如過敏性鼻炎或氣喘),其中該抗原係得自包含該引發過敏原之源材料。