Despite drug advances for Hepatitis C virus (HCV), re-infections remain prevalent in high-risk populations. Unfortunately, the role of preexisting viral immunity and how it modulates re-infection is unclear. GBV-B infection of common marmosets is a useful model to study tissue immune responses in hepacivirus infections, and in this study we re-challenged 4 animals after clearance of primary viremia. Although only low-to-absent viremia was observed following re-challenge, GBV-B viral RNA was detectable in liver, confirming re-infection. Microscopic hepatic lesions indicated severe-to-mild lymphocyte infiltration and fibrosis in 3 out of 4 animals. Further, GBV-B-specific T cells were elevated in animals with moderate-to-severe hepatopathology, and up to 3-fold increases in myeloid dendritic and activated natural killer cells were observed after infection. Our data indicate that occult hepacivirus re-infections occur and that new liver pathology is possible even in the presence of anti-hepacivirus T cells and in the absence of high viremia.

尽管丙型肝炎病毒（HCV）的药物取得了进步，但在高危人群中再感染仍很普遍。不幸的是，目前尚不存在病毒免疫的作用及其如何调节再感染。普通mar猴的GBV-B感染是研究肝炎病毒感染中组织免疫反应的有用模型，在这项研究中，我们在清除原发性病毒血症后再次攻击了4只动物。尽管在再次攻击后仅观察到低至无病毒血症，但在肝脏中可检测到GBV-B病毒RNA，证实了再次感染。肝微观病变表明，每4只动物中有3只有严重至轻度的淋巴细胞浸润和纤维化。此外，在具有中度至重度肝病理的动物中，GBV-B特异性T细胞升高，感染后，观察到髓样树突状细胞和活化的自然杀伤细胞最多增加了3倍。我们的数据表明发生隐匿性肝炎病毒再感染，并且即使存在抗肝炎病毒T细胞且不存在高病毒血症，新的肝脏病理学也是可能的。