ULTRASTRUCTURAL AND IMMUNOCYTOCHEMICAL CHARACTERISTICS OF HEPATOCYTESFROM HEPATITIS-B VIRUS-INFECTED CHIMPANZEES

Liver tissue samples from four chimpanzees submitted to viral challeng e in order to test a recombinant anti-hepatitis B virus vaccine, were studied by electron microscopy. The vaccinated monkeys showed no evide nces of acute viral hepatitis (AVH), demonstrating the protection agai nst an infective viral dose; on the contrary, the non-vaccinated chimp s developed signs of AVH in hepatocytes such as: different size and sh ape, slight dilatation of the rough endoplasmic reticulum, disappearan ce of the mitochondrial crests, broadening of the normal space between the membranes of the nuclear coating and presence of laminar bodies a nd cytoplasmic vacuoles. Furthermore, the presence of the hepatitis B virus surface (HBV) antigen was confirmed in non-vaccinated monkeys us ing immunocytochemical techniques. Transmission electron microscopy an d immunocytochemical analysis corroborated the protective effect of th e recombinant vaccine against the HBV in the vaccinated animals.