Intracytoplasmic crystalline inclusions in the hepatocytes of humans and chimpanzees.

Intracytoplasmic crystalline inclusions (CCIs) were observed in liver biopsy specimens taken from three patients and three chimpanzees. CCIs are rare in human hepatocytes and have never been described in chimpanzees. All three human cases were connected with alcoholic liver disease; no viral infection was noted. The histologies of the two liver biopsy specimens obtained from healthy chimpanzees were normal, but hepatitis B virus (HBV) infection was demonstrated in the third case by immunohistochemistry and radioimmunoassay. In the last biopsy specimen a large accumulation of HBV core particles was present in the nuclei and among the filaments of CCIs of the hepatocytes. This finding suggests that crystallizations of viral proteins may form intracytoplasmic inclusions in hepatocytes, whereas in other cases toxic effects (alcohol) or normal conditions (storage) may lead to the formation of similar structures.