Imiquimod (IMQ) is a TLR7/8 ligand as well as a potent immune activator. It is most commonly known for its anti-viral and anti-tumor applications, however when applied to the skin, it can induce and exacerbate psoriasis. Therefore, it can serve as a preclinical model for studying the pathogenic mechanisms in psoriasis-like dermatitis, which include an influx of various immune cells as well as hyperplasia of the epidermis.
Application of IMQ cream produces the following characteristics:
- erythema, scaling and thickening on the back
- increase in ear thickness
- histological plaque type psoriasis
- infiltration of mononuclear cells, dentritic cells, T cells and neutrophils