ULTRASTRUCTURAL AND IMMUNOCYTOCHEMICAL CHARACTERISTICS OF HEPATOCYTES FROM HEPATITIS-B VIRUS-INFECTED CHIMPANZEES

Liver tissue samples from four chimpanzees submitted to viral challenge in order to test a recombinant anti-hepatitis B virus vaccine, were studied by electron microscopy. The vaccinated monkeys showed no evidences of acute viral hepatitis (AVH), demonstrating the protection against an infective viral dose; on the contrary, the non-vaccinated chimps developed signs of AVH in hepatocytes such as: different size and shape, slight dilatation of the rough endoplasmic reticulum, disappearance of the mitochondrial crests, broadening of the normal space between the membranes of the nuclear coating and presence of laminar bodies and cytoplasmic vacuoles. Furthermore, the presence of the hepatitis B virus surface (HBV) antigen was confirmed in non-vaccinated monkeys using immunocytochemical techniques. Transmission electron microscopy and immunocytochemical analysis corroborated the protective effect of the recombinant vaccine against the HBV in the vaccinated animals.