Vaccine adjuvant uses of poly-IC and derivatives

Pathogen-associated molecular patterns (PAMPs) are stand-alone immunomodulators or 'danger signals,' that are increasingly recognized as critical components of many modern vaccines. Polyinosinic-polycytidylic acid (poly-IC) is a synthetic dsRNA that can activate multiple elements of the host defense in a pattern that parallels that of a viral infection. When properly combined with an antigen, it can be utilized as a PAMP-adjuvant, resulting in modulation and optimization of the antigen-specific immune response. We briefly review the preclinical and clinical uses of poly-IC and two poly-IC derivatives, poly-IC12U (Ampligen) and poly-ICLC (Hiltonol), as vaccine adjuvants.