Fig. 1.

Rat HEV strain LA-B350 is infectious in vivo and in vitro. Four athymic nude rats were inoculated intravenously with LA-B350 and virus quantities in feces and serum (A) and liver (B) were determined by RT-qPCR, documenting robust infection. In a subsequent transmission experiment, LA-B350-infected rats were co-housed with non-infected sentinels. Sentinels displayed robust shedding of virus in stool after 21 and 28 days, indicating efficient transmission of rat HEV (C). Hematoxylin-eosin staining of liver sections showed only very limited infiltration of portal tracks with lymphocytes and polymorphonuclear leucocytes in infected animals (D). LA-B350 also proved infectious in vitro in Huh7 and HepG2/C3A cells: viral RNA released in the culture medium increased over time (E) and high amounts of RNA were detected intracellularly after 20 days (F). Values represent mean±s.e.m. for four animals (A) or from three independent experiments (E,F). The limit of detection for panels E and F is approximately 10³ RNA copies ml⁻¹ culture medium or µg⁻¹ total RNA, respectively. LOD, limit of detection. **P<0.01 (two-tailed t-test).