We show that isostearic acid, a major component of the vehicle, promotes inflammasome activation in cultured keratinocytes, and so may contribute to the observed effects of
Aldara on murine skin.
Aldara therefore stimulates at least two immune pathways independently, and both imiquimod and vehicle are required for a full inflammatory response. Although it remains to be tested, it is possible that imiquimod-independent effects also contribute to the therapeutic efficacy of Aldara.