Challenges of culturing human norovirus in three-dimensional organoid intestinal cell culture models

PLoS One. 2013 Jun 3;8(6):e63485. doi: 10.1371/journal.pone.0063485. Print 2014.

Abstract

Human noroviruses are the most common cause of acute gastroenteritis worldwide. Recently, cell culture systems have been described using either human embryonic intestinal epithelial cells (Int-407) or human epithelial colorectal adenocarcinoma cells (Caco-2) growing on collagen-I porous micro carrier beads in a rotating bioreactor under conditions of physiological fluid shear. Here, we describe the efforts from two independent laboratories to implement this three dimensional (3D) cell culture system for the replication of norovirus. Int-407 and Caco-2 were grown in a rotating bioreactor for up to 28 days. Prior to infection, cells were screened for the presence of microvilli by electron microscopy and stained for junction proteins (zonula occludens-1, claudin-1, and β-catenin). Differentiated 3D cells were transferred to 24-well plates and infected with bacteria-free filtrates of various norovirus genotypes (GI.1, GI.3, GI.8, GII.2, GII.4, GII.7, and GII.8). At 12 h, 24 h, and 48 h post inoculation, viral RNA from both cells and supernatants were collected and analyzed for norovirus RNA by real-time reverse transcription PCR. Despite observations of high expression of junction proteins and microvilli development in stained thin sections, our data suggest no significant increase in viral titer based on norovirus RNA copy number during the first 48 h after inoculation for the different samples and virus culture conditions tested. Our combined efforts demonstrate that 3D cell culture models using Int-407 or Caco-2 cells do not support norovirus replication and highlight the complexity and difficulty of developing a reproducible in vitro cell culture system for human norovirus.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Biomarkers / metabolism
  • Caliciviridae Infections / pathology
  • Caliciviridae Infections / virology
  • Cell Culture Techniques / methods*
  • Cell Differentiation
  • Cell Shape
  • Collagen / metabolism
  • Humans
  • Immunohistochemistry
  • Intestines / cytology*
  • Microvilli / ultrastructure
  • Models, Biological*
  • Norovirus / growth & development*
  • Organoids / virology*
  • Tight Junctions / metabolism
  • Virus Replication

Substances

  • Biomarkers
  • Collagen

Grants and funding

This research was funded in part by the ASM/CDC Fellowship Program in Infectious Disease and Public Health Microbiology for EP. The New Zealand study was funded by the ESR Capability Fund. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.