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Mem Inst Oswaldo Cruz, Rio de Janeiro, Vol. 99(6): 629-631, October 2004 629
SHORT COMMUNICATION
In Situ Hybridization of Hepatitis C Virus RNA in Liver
Cells of an
Experimentally Infected Rhesus Macaque
Selma Majerowicz/
+
, Christopher Grief*, Debora Ferguson, Renata C
Airano,
Marcia L Baptista, Marcelo A Pinto, Ortrud Monika Barth
Departamento de Virologia, Instituto Oswaldo Cruz- Fiocruz, Av. Brasil 4365, 21040-900 Rio de Janeiro, RJ, Brasil
*NIBSC, Potters Bar, Herts, UK
The liver tissue of a rhesus macaque inoculated with hepatitis C virus (HCV) has been
analyzed for the presence
of HCV RNA using the technique of in situ hybridization, both at light and electron
microscopy levels. The animal
was inoculated by the intrasplenic route using a HCV infected autogenic hepatocyte
transplant. The serum sample
used to infect the hepatocyte cells was characterized by polymerase chain reaction
technique and shown to be
positive for HCV RNA, genotype 3 with 107 RNA copies/ml. In situ hybridization was
performed using a complementary
negative strand probe made with the specific primer. We were able to detect and
localize viral RNA in altered
membranes of the rough endoplasmic reticulum of infected liver cells, showing evidence
of virus replication in vivo.
Key words: in situ hybridization - hepatitis C virus - rhesus macaque
Hepatitis C virus (HCV) is a major cause of chronichepatitis, liver cirrhosis, and
hepatocellular carcinoma(Houghton 1996). Identified in 1989, HCV has a
positivestranded RNA and was classified as a Hepacivirus withinthe Flaviviridae
family. Immunolabelling using electronmicroscopy methods of infected cell
culturesrevealed an association of HCV proteins and RNA with altered membranesof
the endoplasmic reticulum, designated the membranousweb, suggesting that this is the
site of viral RNAsynthesis and represents the replication complex of HCV(Egger et al
2002, Gosert et al. 2003). The aim of the presentstudy is to determine the intracellular
localization of theviral RNA and to obtain a better understanding of HCV replication in
vivo. In order to investigate the events inHCV infection, rhesus macaques were
inoculated by the intrasplenic route using a HCV infected autogenic
hepatocytetransplant in one animal, following the techniqueused by Rivas et al. (1994).
The serum sample used was characterized by polymerase chain reaction technique as
positive for HCV RNA, genotype 3 and shown to have107 RNA copies/ml. A suitable
non-inoculated animal wasalso included in the experiment. Liver needle biopsies were
obtained at two weekly intervals from rhesus monkey. Forlight microscopyobservations,
the tissue samples werefixed using neutral buffered 10% formalin and embedded
in paraffin wax. For electron microscopy observations,tissue samples were fixed using
2% glutaraldehyde in 0.06M sodium cacodylate buffer pH 7.4 for 1 h at room
temperaturefollowed by an overnight period at 4oC. The samples were then processed
for low temperature embeddingusing LR gold resin (Grief et al. 1991). Light
andelectron microscopy in situ hybridization was performed using a negative strand