Rotavirus infection of human cholangiocytes parallels the murine model of biliary atresia

Introduction: Biliary atresia (BA) is the leading indication for liver transplantation in the pediatric population. The murine model of BA supports a viral etiology, because infection of neonatal mice with rhesus rotavirus (RRV) results in biliary obstruction. Viral infection targets the biliary epithelium and development of the model is viral strain dependent. No study has yet determined whether human cholangiocytes are also susceptible to rotaviral infection. We established an in vitro human model using an immortalized human cholangiocyte cell line and primary human cholangiocytes obtained from explanted livers to determine human cholangiocyte susceptibility to rotavirus infection.

Methods: Replication and binding assays were performed on immortalized mouse (mCL) and human (H69) cells using six different strains of rotavirus. Primary human cholangiocytes were isolated from cadaveric livers, characterized in culture, and infected with RRV, which causes BA in mice, and another simian strain, TUCH, which does not cause BA in mice.

Results: Immortalized mouse and human cholangiocytes demonstrated similar patterns of infectivity and binding with different strains of rotavirus. Both cell lines produced a significantly higher viral yield with RRV infection than with the other strains tested. In primary human cholangiocytes, which maintained their epithelial characteristics, as demonstrated by cytokeratin staining, RRV replicated to a yield 1000-fold higher than TUCH.

Conclusions: Both immortalized and primary human cholangiocytes are susceptible to RRV infection in a fashion similar to murine cholangiocytes. These novel findings suggest rotavirus infection could have a potential role in the pathogenesis of human BA.