Polyethyleneimine is a potent mucosal adjuvant for viral glycoprotein antigens

No mucosal adjuvant formulation is approved for clinical use, even though boosting immunity at sites of pathogen entry should increase the efficacy of nonreplicating vaccines. Wegmann et al . report that polyethyleneimine (PEI) acts as a potent mucosal adjuvant for protein antigens from influenza and herpes simplex virus, protecting mice against otherwise lethal infections.