Loxoribine is a guanosine derivative and an agonist of toll-like receptor 7 (TLR7). It is selective for TLR7 over other human TLRs in a cell-based reporter assay at 1 mM.. Loxoribine induces proliferation, increases the antibody response to sheep red blood cells, and activates natural killer cell activity against Yac-1 lymphoma cells in murine splenocyte cultures (EC50s = 10-50, 3-20, and 13-22 μM, respectively). Loxoribine (250 μM) increases production of IL-12, IL-23, IL-27, and IL-10 by human monocyte-derived dendritic cells (MoDCs). Loxoribine-treated MoDCs induce higher levels of IL-17 and IFN-γ secretion by co-cultured allogeneic CD4+ T cells compared to control MoDCs. Loxoribine (120 mg/kg) reduces the number of pulmonary metastases in the B16 mouse model of melanoma, an effect enhanced by co-administration of IL-2, and exhibits adjuvant activity in mice immunized with a B16 tumor vaccine.
Small-molecule immunostimulants
Loxoribine is a selective toll-like receptor 7 (TLR7) agonist that activates immune cells and increases cytokine production.
7-Allyl-7,8-dihydro-8-oxoguanosine (Loxoribine) is a small-molecule immunostimulant. Loxoribine is a toll-like receptor 7 (TLR7) agonist; induces immune cell activation and increases cytokine product
ion. Loxoribine displays antitumor and antiviral activity in various animal models.
Toll-like receptor 7 (TLR7) agonist; induces immune cell activation and increases cytokine production. Displays antitumor and antiviral activity in various animal models.
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