Imiquimod | TLR7 Agonist

Imiquimod (99011-02-6) is a Toll-like receptor 7/8 agonist with anti-viral and anti-tumor properties.¹ Enhances innate immune system leading to Th1-mediated antitumor immune response.² Increases levels of IFNα, TNFα, and IL-12. Imiquimod has also been shown to act as an antagonist at adenosine A1 and A2A receptors augmenting its proinflammatory effects.^3,4 Clinically useful for the treatment of basal cell carcinoma, actinic keratosis, and genital warts.  Imiquimod also upregulates the expression of opioid growth factor receptor(OGFr).^5,6 OGF is involved in regulation of inhibitory kinases in the cell cycle process.

References/Citations:

1) Hemmi et al. (2002), Small anti-viral compounds activate immune cells via the TLR7 MyD88-dependent signaling pathway; Nat. Immunol. 3 196
2) Stanley et al. (2002), Imiquimod and the imidazoquinolones: mechanism of action and therapeutic potential; Clin. Exp. Dermatol. 27 571
3) Schoen et al. (2006), The small antitumoral immune response modifier imiquimod interacts with adenosine receptor signaling in a TLR7- and TLR8-independent fashion; J.Invest.Dermatol. 126 1338
4) Kan et al. (2012), Imiquimod Suppresses Propagation of Herpes Simplex Virus 1 by Upregulation of Cystatin A via the Adenosine Receptor A₁ Pathway.; J. Virol. 86 10338
5) Urosevic et al. (2004), Imiquimod Treatment Induces Expression of Opioid Growth Factor Receptor; Clin. Cancer Res. 10 4959
6) Zagon et al. (2008), Imiquimod Upregulates the Opioid Growth Factor Receptor to Inhibit Cell Proliferation Independent of Immune Function.; Exp. Biol. Med.(Maywood) 233 968