| Description |
Motolimod is a selective Toll-like receptor 8 (TLR8) agonist, with an EC50 of approximately 100 nM.
|
| Related Catalog |
|
| Target |
EC50: 100 nM (TLR8)[1]
|
| In Vitro |
Among the TLRs tested (TLR2, 3, 4, 5, 7, 8, and 9), Motolimod (VTX-2337) selectively activates TLR8. Motolimod stimulates the production of both TNFα (EC50=140±30 nM based on 10 donors) and IL-12 (EC50=120±30 nM based on 10 donors) in PBMCs. The EC50 value for MIP-1β induction is 60 nM for Motolimod[1].
|
| In Vivo |
Monkeys receive a subcutaneous injection of Motolimod (1 or 10 mg/kg), and plasma is collected predose, 6, 12, 24, and 96 h post-injection. For the 10 mg/kg dose, mean plasma levels of IL-1β increase from baseline levels of 0.5 pg/mL, up to 9.12±2.7 ng/mL (p<0.05, t-test) at 6 h post-administration of Motolimod (10 mg/kg). Circulating levels of IL-18 also increase from a baseline of ~ 1 pg/mL to 68.7±4.4 pg/mL (p<0.05, t-test) at 6 h in response to the Motolimod (VTX-2337) treatment (10 mg/kg). Levels of IL-6 are monitored, as this mediator is induced in response to TLR8 activation, but the release is independent of NLRP3 inflammasome activation. In addition, plasma levels of IFNγ are assessed as a measure of NK cell activation in response to Motolimod treatment[2].
|
| Kinase Assay |
Human embryonic kidney cells (HEK293) expressing TLR2, 3, 4, 5, 7, 8, or 9 are cultured in Dulbecco's Modified Eagle's Media containing 4.5 g/L L-glucose and 10% FBS. The activity of specific TLR agonists is assessed using the secretory embryonic alkaline phosphatase (SEAP) reporter gene that is linked to NF-κB activation in response to TLR stimulation. Measurement of SEAP activity using the Quanti-blue substrate after TLR agonist treatment is carried out similarly[1].
|
| Cell Assay |
PBMCs or purified NK cells are prepared, and the purity of NK cells is approximately 99%. NK cell-mediated cytotoxicity is assessed by Calcein AM release from labeled target cells. In brief, PBMCs or purified NK cells are cultured for 48 hours in RPMI medium in the presence of Motolimod (167 or 500 nM) before incubation with target cells[1].
|
| Animal Admin |
Monkeys[2] The male monkeys (2.9-4.9 kg) are housed individually (cage dimensions of 0.76 m wide×0.74 m deep×0.81 m in height), but commingled periodically as part of the environmental enrichment program. The animals are also given fruit, vegetable, or additional supplements as a form of environmental enrichment, as well as given various cage enrichment devices. Animals are given Certified Primate Diet, two times daily and water ad libitum. Motolimod is administered as a bolus subcutaneous (SC) injection in the intrascapular area at doses of 1 and 10 mg/kg. Blood samples are collected at baseline (pre-dose), and 6, 12, 24, and 96 h post injection to monitor levels of IL-1β and IL-18 in the plasma using the human MAP v.1.6 inflammation panel.
|
| References |
[1]. Lu H, et al. VTX-2337 is a novel TLR8 agonist that activates NK cells and augments ADCC. Clin Cancer Res. 2012 Jan 15;18(2):499-509. [2]. Dietsch GN, et al. Coordinated Activation of Toll-Like Receptor8 (TLR8) and NLRP3 by the TLR8 Agonist, VTX-2337, Ignites Tumoricidal Natural Killer Cell Activity. PLoS One. 2016 Feb 29;11(2):e0148764.
|
