Resiquimod (R-848),144875-48-9,IC-0237380

Resiquimod (R848) is an imidazoquinoline compound with potential antiviral activity. It is a low molecular weight synthetic molecule that has been evaluated in clinical studies for the treatment of infections caused by viruses such as herpes simplex virus and hepatitis C virus[1]. Resiquimod was found to reduce viral shedding and viral reoccurrence by activating various immune cells to produce an environment conductive for the T-helper 1 (Th1) immune responses[2-3]. Resiquimod is a selective ligand for Toll-like receptor (TLR) 7 in mouse and for TLR7 and TLR8 in human and has been shown to activate only TLR7 and TLR8[4].

Resiquimod(10 µg/ml; 6 or 12 h) induced the increase of high-affinity IgE receptor (FcεRI) expression in native mast cells [5].

Resiquimod 8(3 mg/kg;i.p ; three continuous days in a week for three weeks) exhibited a robust antitumoral effect. Resiquimod reduced tumor vasculature and induced tumor cell apoptosis. Resiquimod increased high mobility group Box 1 expression in tumor tissues and activated CD4+ T cells in the peripheral blood[6]. Resiquimod (10 g; i.p) induces anti-tumor responses and attenuates cachexia in murine models of pancreatic ductal adenocarcinoma (PDAC)[7]. The combination of Resiquimod (3 mg/kg were administered by retro-orbital injections (diluted in PBS, 100 µL per mouse) 1 day before, 1 day after, and 1 week after SBRT treatments (total of 3 times))and SBRT results in significant immune activation of the pancreatic tumor microenvironment (TME), including increased tumor antigen-specific CD8+ T cells, decreased regulatory T cells, and enhanced antigen-presenting cells maturation, as well as increased interferon gamma, granzyme B, and CCL5 along with decreased levels of interleukin 4 (IL-4), IL-6, and IL-10[8].