Arch Virol (1998) 143: 571–579
Lack of restriction of growth for aquareovirus
in mammalian cells
S. K. Samal
, T. H. McPhillips
, D. Dinan
, and D. D. Rockemann
VA-MD Regional College of Veterinary Medicine, University of Maryland,
College Park, Maryland, U.S.A.
Department of Biology, La Salle University, Philadelphia, Pennsylvania, U.S.A.
Accepted October 28, 1997
Summary. The striped boss (SBR) virus, a member of the recently described
aquareoviruses, infected, caused cytopathic effects (CPE), and replicated in
mammalian cells. The virus caused CPE in all 7 of the mammalian cell lines
investigated. SBR virus functioned best at lower temperatures and it is these
lower temperatures that appeared to be restricting factors for growth of some
mammalian cells. At 22
C the SBR virus grew to similar titers in both chinook
salmon embryo (CHSE) cells and in mammalian cells. Analysis of viral polypep-
tide and RNA synthesis suggests that the restriction for viral growth at higher
temperatures occurs after adsorption but before transcription and translation of
viral genes. The fact that SBR virus did not grow at 37
C implies that aquareo-
viruses are unlikely to be human pathogens.
Aquareoviruses have been isolated from a wide variety of aquatic organisms
throughout the world . While their role in pathogenesis is not well under-
stood, it is clear that some members of this group are ﬁsh pathogens capable of
causing hemorrhagic disease, hepatitis and pancreatitis [1, 2, 6]. These diseases
pose a signiﬁcant threat to the aquaculture industry and raise concerns about the
transmissibility of these pathogens to mammals, including humans.
The aquareoviruses are members of the family Reoviridae. They consist of a
double-capsid with 7 structural proteins (VP 1 through 7) and a genome composed
of 11 segments of double-stranded RNA [3, 7, 9].
As is the case with other viruses isolated from aquatic organisms, the aquareo-
viruses have routinely been cultured at low temperatures (e.g. 16
C) in cell lines