Hepatitis C Virus Resistance to Carbohydrate-Binding Agents

Izquierdo, Laure; Oliveira, Catarina; Fournier, Carole; Descamps, Véronique; Morel, Virginie; Dubuisson, Jean; Brochot, Etienne; Francois, Catherine; Castelain, Sandrine; Duverlie, Gilles; Helle, Francois

In order to study viral resistance to CBAs, we cultivated HCV in vitro in the presence of increasing concentrations of different high-mannose specific lectins: GNA, CV-N, ConA and GRFT. We took advantage of the HuH-7-RFP-NLS-IPS cell line which enables to monitor HCV infection in living cells [17, 19] . First, we infected HuH-7-RFP-NLS-IPS cells in the presence of the 90% effective concentration of each lectin (1, 0.1, 2 and 1 μg/mL for GNA, CV-N, ConA and GRFT, respectively). Infected cells were then subcultured every three to four days in the presence of the lectin until 100% cells were infected. As soon as all cells were infected, supernatants were recovered and used to infect naive cells in the presence of the lectins. The concentrations of each lectin were increased in a stepwise manner as described in Fig 1. In these conditions, we were able to propagate HCV in the presence of 30 μg/mL of GNA after three months and 2 μg/mL of CV-N after two months. The highest possible ConA concentration was 10 μg/mL due to toxicity of the drug in the cell culture at higher concentrations (S1 Fig). Remarkably, it was difficult to propagate the virus in the presence of GRFT suggesting that adaptation of HCV to this lectin was more challenging. To confirm that we isolated CBA resistant strains, we compared the sensitivity of the isolated strains and the parental strain to lectins. As shown in Fig 2, we observed that the strains isolated in the presence of GNA, CV-N and GRFT were less sensitive to these lectins than the parental strain. In contrast, the strain isolated in the presence of ConA seemed to be as sensitive as the parental strain to ConA.