Proliferative Cell Targeting and Epithelial Cell Turnover Fuels Hepatitis E Virus Replication in Human Intestinal...

Area of Science:

• Virology
• Gastroenterology
• Infectious Diseases

Background:

• Hepatitis E virus (HEV) is a major cause of acute viral hepatitis worldwide.
• HEV transmission is primarily fecal-oral, but its role in gut pathogenesis is poorly understood.
• Key questions include HEV dissemination from the gut and its potential as a reservoir.

Purpose of the Study:

• To investigate HEV biology within the human gut.
• To establish and utilize a human intestinal enteroid (HIE) model for HEV studies.
• To elucidate HEV replication, dissemination, and tropism in the intestinal epithelium.

Main Methods:

• Development of three HEV-HIE models: 3D HIEs, 2D transwell HIEs, and electroporated HIEs.
• Characterization of HEV particles using western blot and gradient centrifugation.
• Confocal microscopy and gene expression analysis to assess intestinal tropism.

Main Results:

• Electroporated HIEs yielded high titers of infectious nonenveloped HEV virions capable of reinfection.
• HEV efficiently infected proliferative cells, including intestinal stem cells and transit-amplifying cells (70% of infected cells).
• HEV capsid protein (ORF2) was detected in enterocytes, goblet cells, and enteroendocrine cells.

Conclusions:

• A robust HEV-HIE model was established, enabling high-titer infectious virion production.
• Rapid intestinal epithelial cell turnover and proliferative cell tropism are crucial for HEV replication and dissemination.
• The human gut serves as an HEV reservoir, contributing to fecal HEV shedding.