INSITU HYBRIDIZATION STUDIES IN HEPATITIS-A INFECTION

An in situ hybridization method using radiolabeled oligonucleotide probes was developed to study primary sites of hepatitis A virus replication in an experimental animal model of infection. Hepatitis A genomic sequences were demonstrated in hepatocytes of four marmosets with acute hepatitis A by use of antisense probes. In two of these animals, staining was also found when a sense probe was used, which is consistent with active replication in the hepatocytes. The specificity of the hybridization signal was confirmed by neutralization with "cold" (i.e., unlabeled) probes and by absence of hybridization with non-A hepatitis and reverse antisense probes. The hepatocyte appeared to be the only cell type showing staining. No hybridization was found in other organs, including the intestine (n = 4) and, in one animal, the kidney and spleen.