Non-A, Non-B Hepatitis in Chimpanzees and Marmosets

Abstract

Nine of 15 specimens of human origin thought to contain non-A, non-B hepatitis agents caused hepatitis in recipient chimpanzees. Two have been further characterized. One inoculum, designated strain F, has been reported to produce unique cytoplasmic changes detected by electron microscopyin liverbiopsy specimens;the other, strain H, produced distinctive nuclear changes. It is not yet clear whether these two changes result from infection by different agents; they have been useful markers of non-A, non-B hepatitis in chimpanzees. Strain F was seriallypassaged sixtimes in chimpanzees, and the infectivity titer of the strain F plasma wasestimated to be 2/ml. Strain H had an infectivity titer in chimpanzees of at least 10⁶/ml Both the strain F and strain H agents have been successfully transmitted and serially passaged in marmosets. Although hepatitis was detected in a lower percentage of marmosets than chimpanzeesgiven either the strain F or H inoculum, the infectivity titer of the strain H agent appeared to be ~ 108 marmoset infectious doses/ml.