SARS-coronavirus replication in human peripheral monocytes/macrophages

Virus Res. 2005 Jan;107(1):93-101. doi: 10.1016/j.virusres.2004.09.004.

Abstract

A novel coronavirus (CoV) has been described in association with cases of severe acute respiratory syndrome (SARS). The virus, SARS-CoV, differs from the previously described human coronaviruses, 229E and OC43. 229E was previously shown to productively infect human monocytes/macrophages, whereas OC43 poorly infected the cells. In this study, we examined whether SARS-CoV could productively infect purified monocytes/macrophages (PM) derived from human donor cells. Unlike 229E-infected cells, which produced viral titers of 10(3.5) to 10(6)TCID50/ml, SARS-CoV replicated poorly in PM, producing titers of 10(1.75) to 10(2)TCID50/ml. This finding was similar to results reported for OC43-infected cells, with titers ranging from 10(1.2) to 10(2.7)TCID50/ml. Of interest, SARS-CoV proteins were detected only in PM that did not produce significant amounts of interferon (IFN)-alpha, and in one such case, preliminary electron microscope studies demonstrated that SARS-CoV-like particles could enter the cells, possibly via phagocytosis. These results suggest that SARS-CoV, like human CoV OC43, poorly infects human PM, and production of IFN-alpha by these cells further limits the infection. Given the importance of monocytes/macrophages to the immune response, it is possible that their infection by SARS-CoV and alteration of this infection by IFN-alpha may be important to the course of the infection in humans.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Antibodies, Viral
  • Humans
  • In Vitro Techniques
  • Interferon-alpha / biosynthesis
  • Macrophages / ultrastructure
  • Macrophages / virology*
  • Microscopy, Electron
  • Monocytes / ultrastructure
  • Monocytes / virology*
  • Phagocytosis
  • SARS Virus / immunology
  • SARS Virus / pathogenicity
  • SARS Virus / physiology*
  • SARS Virus / ultrastructure
  • Severe Acute Respiratory Syndrome / virology
  • Virus Replication

Substances

  • Antibodies, Viral
  • Interferon-alpha