Similarly, CDs used for the treatment of RSV and PRRSV were able to activate the innate immune response via an upregulation of ISGs in vitro.130 Gold nanorods were applied to boost the innate immune response against RSV in vivo.131 Interestingly, it was shown that these nanorods (when intranasally administered with RSV) were not only able to activate the ISGs but also to tune the production of pro- and anti-inflammatory cytokines, resulting in the blocking of the infection with a reduced pulmonary inflammation.131 As drug carriers, HNMs can also affect the internalization pathways, modulate drug efficacy, and the immune cell responses. For instance, it was found that the isoprinosine immunomodulatory antiviral drug displays a much higher antiviral efficacy in vivo when delivered with CNTs than as a pure drug (in zebrafish larvae food administration), probably due to a better cellular uptake and the anti-inflammatory properties of the nanotubes.132