Pulmonary surfactant–biomimetic nanoparticles potentiate heterosubtypic influenza immunity

Pitching cGAMP as a vaccine strategy One strategy to address the variable effectiveness of many influenza vaccines is to induce antiviral resident memory T cells, which can mediate cross-protection against multiple substrains (heterosubtypic immunity). Unfortunately, such vaccines typically use attenuated active viruses, which may be unsafe for certain populations. Wang et al. report a vaccine using an inactivated virus that effectively induced heterosubtypic immunity in both mice and ferrets (see the Perspective by Herold and Sander). They coadministered the virus with 2′,3′-cyclic guanosine monophosphate–adenosine monophosphate (cGAMP), a potent activator of the innate immune system, encapsulated in pulmonary surfactant–biomimetic liposomes. This adjuvant was taken up by alveolar epithelial cells, whose activation resulted in effective antiviral T cell and humoral immune responses without accompanying immunopathology. Science , this issue p. eaau0810 ; see also p. 852