Polyinosinic-polycytidylic acid (Poly(I:C)) sodium is a synthetic analog of double-stranded RNA and an agonist of toll-like receptor 3 (TLR3) and retinoic acid inducible gene I (RIG-I)-like receptors (RIG-I and MDA5). Polyinosinic-polycytidylic acid sodium can be used as a vaccine adjuvant to enhance innate and adaptive immune responses, and to alter the tumor microenvironment. Polyinosinic-polycytidylic acid sodium can directly trigger cancer cells to undergo apoptosis[2].IC50 & Target:TLR3[2], RIG-I[2], MDA5[2], apoptosis[2]In Vitro:Polyinosinic-polycytidylic acid (20 ng/mL; 24 hours; WM793, WM278, WM239A, WM9 and 1205Lu cells) treatment strongly reduces viability from 100% in controls to 20%–50% within 24 hours.
Polyinosinic-polycytidylic acid (200 ng/mL; 24 hours; 1205Lu cells) treatment induces apoptosis in 1205Lu cells.
Polyinosinic-polycytidylic acid (3 ng/mL; 24 hours; 1205Lu cells) treatment induces IFN-β expression in melanoma cells. Silencing of RIG-I and MDA-5 confirmed that induction of IFN-β by Polyinosinic-polycytidylic acid required RIG-I and MDA-5, respectively, and that required IPS-1.
Polyinosinic-polycytidylic acid (5 ng/mL; 24 hours; 1205Lu cells) treatment reveals active subunits of caspase-9 and caspase-8 in melanoma cells.
Polyinosinic-polycytidylic acid sodium is prepared for injection by resuspending in sterile saline, heating to 50 °C at a concentration of 2 mg/mL to ensure complete solubilisation and then allowing to cool naturally to room temperature to ensure proper annealing of double-stranded RNA. Polyinosinic-polycytidylic acid is stored at -20 °C until use.
In Vivo:Polyinosinic-polycytidylic acid treatment inhibits tumor growth in NOD/SCID immunodeficient mice injected with 1205Lu cells. The level of human DNA is 50% lower in mice treated with Polyinosinic-polycytidylic acid.