Name
Fucosidase activity modulates human rotavirus infection: insights from “in vitro” and “in vivo” models
Presenter
Jesus Rodriguez-Diaz, Universitat de Valencia
Co-Author(s)
Sonia Llanos-Villatoro, Nazaret Peña-Gil, Roberto Cárcamo-Calvo, Sergi López-Navarro, Cristina Santiso-Bellón, Roberto Gozalbo-Rovira, Javier Buesa, and Jesús Rodríguez-Díaz
Departamento de Microbiología y Ecología, Facultad de Medicina y Odontología, Universitat de València, AV. Blasco Ibáñez 15, Spain
Abstract Category
Cell Biology of Viral Infection
Abstract
Human rotavirus (RV), utilizes histo-blood group antigens (HBGAs) as receptors for host cell attachment. HBGAs are fucosylated carbohydrates expressed in the gastrointestinal tract. Several studies have highlighted the role of gut microbiota in either promoting or inhibiting RV infections. The gut microbiota produces a diverse array of glycosyl hydrolases, including fucosidases, that enable them to utilize host glycans as a nutrient source.
To investigate the impact of bacterial fucosidases on human RV infections, two fucosidases from Bifidobacterium bifidum were selected: AfcA, an α1-2 fucosidase, and AfcB, an α1-3/4 fucosidase. Differentiated Caco-2 cells (dCaco-2) were pretreated with these enzymes prior to RV infection. The results demonstrated increased viral attachment, replication, and yield for two non-cell culture-adapted RV strains. Additionally, “in vivo” experiments were conducted using mice infected with the RV Wa strain following AfcA treatment. A significant increase in viral shedding, along with prolonged shedding duration, was observed.
Given that RVs appeared to benefit from fucosidase treatment, the effect of a fucosidase inhibitor, 1-deoxyfuconojirimycin, was also evaluated. Viral stocks were incubated with varying concentrations of the inhibitor, and its impact on RV replication was assessed through multiple “in vitro” and “in vivo” assays. These included infections with clinical human RV isolates and the Wa strain in dCaco-2 cells, as well as RV Wa infection in mice. Across all experiments, fucosidase inhibition consistently resulted in reduced viral replication.
Our findings suggest that the balance between HBGA binding activity and fucosidase activity plays a crucial role in the efficient replication of human RV.
To investigate the impact of bacterial fucosidases on human RV infections, two fucosidases from Bifidobacterium bifidum were selected: AfcA, an α1-2 fucosidase, and AfcB, an α1-3/4 fucosidase. Differentiated Caco-2 cells (dCaco-2) were pretreated with these enzymes prior to RV infection. The results demonstrated increased viral attachment, replication, and yield for two non-cell culture-adapted RV strains. Additionally, “in vivo” experiments were conducted using mice infected with the RV Wa strain following AfcA treatment. A significant increase in viral shedding, along with prolonged shedding duration, was observed.
Given that RVs appeared to benefit from fucosidase treatment, the effect of a fucosidase inhibitor, 1-deoxyfuconojirimycin, was also evaluated. Viral stocks were incubated with varying concentrations of the inhibitor, and its impact on RV replication was assessed through multiple “in vitro” and “in vivo” assays. These included infections with clinical human RV isolates and the Wa strain in dCaco-2 cells, as well as RV Wa infection in mice. Across all experiments, fucosidase inhibition consistently resulted in reduced viral replication.
Our findings suggest that the balance between HBGA binding activity and fucosidase activity plays a crucial role in the efficient replication of human RV.