Compositions and methods for modulating the innate and adaptive immune systems in a subject. The compositions and methods may inhibit the function of inhibitory receptors and enhance activity of activating receptors. The method typically includes the steps of: administering to the subject a composition having a therapeutic peptide or multivalent polypeptide having multiple copies of the therapeutic peptide in an amount sufficient to increase activity of the immune system in the subject. Compositions may include a carrier at least one agent selected from the group consisting of: an anti-inflammatory agent, a cytotoxic T cell proliferation agent, and/or a NK cell proliferation agent and a selected therapeutic peptide or multivalent polypeptide. The compositions may also include an immunoglobulin admixed therewith to enhance passive immunoprotection.
