Aldara is a topical cream formulation of imiquimod (IMQ) that stimulates an antitumour inflammatory immune response for the treatment of non-melanoma skin cancers. Walter et al. examined the effects of Aldara on the skin of healthy mice and found that much of the inflammatory response is independent of the action of IMQ on its target Toll-like receptor 7 (TLR7): various aspects of the immune response occurred using cream without IMQ or when applying Aldara to Tlr7-null mice. Other components of the cream, such as isostearic acid, were found to be important for inducing an immune response.