CHEMBL5736220

HBV DNA Quantification Assay: A HepG2 cell line overexpressing the HBV virus attachment receptor sodium-taurocholate cotransporting polypeptide (NTCP) was grown to confluency in DMEM growth medium, Dulbecco's Modified Eagle Medium without sodium pyruvate (Life Technologies, Rockville, Md.) supplemented with 10% FBS (Thermo Scientific, Waltham, Md.), 1% penicillin/streptomycin (Life Technologies, Rockville, Md.) and 2 mM L-glutamine (Life Technologies, Rockville, Md.) in T175 flasks. Cells were infected with HBV AD38 viral particles (Texcell, Frederick, USA) at 4000 genome equivalents per cell. After allowing viral infection to take place for 4 days, the infected cells were harvested from the flasks by trypsinization, washed twice with OptiMEM (Life Technologies, Rockville, Md.) and re-suspended in DMEM containing 2% FBS and 1% DMSO at a density of 0.25E6 cells/ml. Infected cells were seeded on 384 well collagen coated plates (Greiner, Austria) at a density of 20,000 cells/well containing serially diluted compounds of the present disclosure or DMSO (0.5%) in a final volume of 80 μl. The assay plates were incubated for a period of 5 days and the antiviral activity of the test compounds were assayed by detecting the presence of HBV DNA in the culture supernatant using the QuantiGene™ 2.0 nucleic acid quantification kit (Affymetrix, Santa Clara, Calif.).The culture supernatant was harvested and treated with lysis buffer containing Proteinase K (Affymetrix, Santa Clara, Calif.). The supernatant was incubated with HBV viral DNA specific probes (Affymetrix, Santa Clara, Calif.) for 30 minutes at 55° C. This was followed by addition of 0.2M NaOH for 30 minutes at room temperature to denature the DNA, followed by addition of Neutralization buffer (Affymetrix, Santa Clara, Calif.). The resulting lysed and neutralized supernatant was then added to QuantiGene™ 2.0 384 well plates coated with capture oligonucleotides and incubated overnight at 55° C. The HBV specific probe set consists of Capture Extender oligonucleotides (CE's) and blocking probes. Following the overnight incubation, the wells were incubated for one hour sequentially with a Pre-Amplifier, Amplifier and Labeled probes conjugated to alkaline phosphatase with a wash step between incubations. After the final wash step, the alkaline phosphatase substrate (Luminol APS5) was added and the resulting luminescence signal was read in an EnVision Multilabel Plate Reader (PerkinElmer, Santa Clara, Calif.). The EC50 values were calculated from the fit of the dose-response curves to a four-parameter equation.