Immunogenic substances comprising a polyinosinic acid-polycytidilic acid based adjuvant

The present invention provides a polynucleotide adjuvant (PICKCa) composition and methods of use in eliciting an immune response, in particular a mucosal immune response. The polynucleotide adjuvant comprises of a polyriboinosinic-polyribocytidylic acid (PIC), at least one antibiotic and at least one positive ion. The present invention also provides an immunogenic composition comprising the polynucleotide adjuvant composition together with other immunogenic compositions such as an antigen (e.g., as in a vaccine) selected from viral, bacterial, fungal, parasitic and/or cancer antigens. The present invention further contemplates methods of use of such adjuvant compositions, particularly in eliciting an immune response, in particular a mucosal immune response to an antigenic compound.