The present invention relates to a nucleic acid of the general formula (I): GlXmGn, or (II): ClXmCn, which may be modified by a lipid. The nucleic acid of the invention acts as an immune-stimulating agent inducing the innate immune response. The invention relates further to a pharmaceutical composition (in a first embodiment), each containing an immune-stimulating agent according to the invention in combination with a pharmaceutically active carrier/vehicle (and, optionally, further auxiliary substances, additives and/or further adjuvants). In another embodiment, the inventive nucleic acid is combined with at least one pharmaceutically active component, a pharmaceutically acceptable carrier/vehicle (and, optionally, further auxiliary substances, additives and/or further adjuvants). Accordingly, the presemt invention is directed to a vaccine, which corresponds to a pharmaceutical composition of the invention (second embodiment), wherein the pharmaceutically active component induces a specific immune response (e.g. an antigen). The present invention relates likewise to the use of a nucleic acid of the invention or a pharmaceutical composition according to the invention for the treatment of infectious diseases, autoimmune diseases, allergies or cancer diseases.
