The present invention relates generally to an immunotherapeutic composition. More particularly, the present invention relates to an immunotherapeutic composition which interacts immunologically with T lymphocytes in subjects having peanut allergy or allergy to other tree nuts. This composition is preferably immunointeractive with T cells in subjects having an allergy to the Ara h 1 and/or Ara h 2 allergens. The composition of the present invention is useful in the therapeutic or prophylactic treatment of conditions characterised by an aberrant, inappropriate or otherwise unwanted immune response to peanut, Ara h 1 and/or Ara h 2 or derivative or homologue thereof.