Arch Virol (2001) 146: 2239–2247
Cultures of equine respiratory epithelial cells and organ explants
as tools for the study of equine inﬂuenza virus infection
, R. E. Holland Jr, N. M. Williams, and T. M. Chambers
The Maxwell H. Gluck Equine Research Center, Department of Veterinary Science,
University of Kentucky, Lexington, Kentucky, U.S.A.
Accepted May 7, 2001
Summary. Equine nasal turbinate epithelial cells and tracheal rafts were main-
tained with sustained viability in culture. Both types of culture supported produc-
tive replication of equine inﬂuenza virus (equine-2, subtype H3N8) and cell death
occurred through apoptosis following viral infection. Thus, primary respiratory
epithelial cell and organ cultures of equine origin may be valuable as alternatives
to the intact animal for studying the virus-host interaction of equine respiratory
viruses including inﬂuenza.
Respiratory tract disease has been recognized as a major health problem affecting
horses. Among the various causes, equine inﬂuenza virus (EIV) is probably the
most common . Virus replication destroys the function of the respiratory
mucociliary escalator and may result in secondary bacterial complications .
Epizootics of inﬂuenza can lead to considerable economic losses to the horse in-
dustry. Although infection of inﬂuenza virus has been shown to primarily affect
the respiratory tract epithelia, the process of the developing infection and cellular/
molecular pathology in the equine respiratory tract caused by this virus have not
been well studied. Detailed understanding of the EIV pathogenesis in the native
host, the horse, is critical for efforts to control EIV infection and this viral disease.
Moststudiesofinﬂuenzavirusreplicationhave been performed in cell cultures
using established cell lines or in chicken eggs [4, 11, 15, 17]; however, eggs or cell
lines are not fully adequate models for equine inﬂuenza viruses because adaption
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