High-Titer Hepatitis C Virus Production in a Scalable Single-Use High Cell Density Bioreactor

Thu Apr 28 11:42:16 CST 2022

2. Materials and Methods

2.1. Maintenance of Huh7.5 Cells

Huh7.5 cell cultures were maintained in cell culture T flasks in serum-containing medium (SCM): Dulbecco’s Modified Eagle Medium (DMEM) (Gibco, Paisley, UK) containing 4 mM GlutaMAX and supplemented with 10% fetal bovine serum (Sigma, St. Louis, MO, USA), 100 U/mL penicillin and 100 µg/mL streptomycin (Sigma). In T175 flasks (Nunc, Roskilde, Denmark) and triple layer culture flasks (Nunc), Huh7.5 cells were passaged every 2–3 days. All cell cultures were maintained at 37 °C and 5% CO2.

Cell Factory Systems

2.2. HCV Virus Stocks

Two sequence-confirmed stocks of the genotype 5a recombinant SA13/JFH1core-NS5B [28], grown in monolayer Huh7.5 cell cultures in T flasks, were used in this study. A third passage virus stock with an infectivity titer of 5.8 log10 FFU/mL, grown under serum-containing (SC) conditions [39], was used to inoculate CelCradle™ cultures, shake flask cultures, and for virus characterization experiments. A fourth passage virus stock with an infectivity titer of 5.1 log10 FFU/mL [32], grown under SF conditions [39], was used for virus characterization experiments.

Source from: 

The FAI climbed 5.9 percent year-on-year in the first 11 months of 2018, quickening from the 5.7-percent growth in Jan-Oct, the National Bureau of Statistics (NBS) said Friday in an online statement.

The key indicator of investment, dubbed a major growth driver, hit the bottom in August and has since started to rebound steadily.

In the face of emerging economic challenges home and abroad, China has stepped up efforts to stabilize investment, in particular rolling out measures to motivate private investors and channel funds into infrastructure.

Friday's data showed private investment, accounting for more than 60 percent of the total FAI, expanded by a brisk 8.7 percent.

NBS spokesperson Mao Shengyong said funds into weak economic links registered rapid increases as investment in environmental protection and agriculture jumped 42 percent and 12.5 percent respectively, much faster than the average.

In breakdown, investment in high-tech and equipment manufacturing remained vigorous with 16.1-percent and 11.6-percent increases respectively in the first 11 months. Infrastructure investment gained 3.7 percent, staying flat. Investment in property development rose 9.7 percent, also unchanged.