Compositions comprising one or more isolated nucleic acid molecules that encode an immunogen in combination with one or more of CTACK protein, TECK protein, MEC protein and functional fragments thereof and/or an isolated nucleic acid molecule that encodes a protein selected from the group consisting of: CTACK, TECK, MEC and functional fragments thereof are disclosed. Methods of inducing an immune response, including methods of inducing mucosal immune responses, in an individual against an immunogen, using such compositions are disclosed.