Changes of Kupffer cells during tree shrew chronically infected with hepatitis B virus

AIM：To explore the changes and significance of Kupffer cells in the process of tree shrew chronically infected with hepatitis B virus (HBV). METHODS：The animals were divided into 3 groups. Group A consists of 6 tree shrews that were identified as persistently infected with HBV; group B consists of 3 tree shrews that were suspected as persistently infected with HBV; group C consists of 4 tree shrews that were not inoculated with HBV and were applied as normal controls. Liver biopsies were collected regularly from all animals, and the Kupffer cells were isolated, purified and primarily cultured. The techniques of flow cytometry, immunohistochemistry, lysosomal fluorescent probe staining and real-time RT-PCR were applied to determine the number and function of these Kupffer cells. RESULTS：The result showed that the count and proportion of CD163+ cells in group A were significantly higher than those in group B and group C (P<0.05). Meanwhile, the fluorescence intensity levels of lysosomal, the number of lysozyme-positive cells and the mRNA expression level of TNF-α in the Kupffer cells in group A were significantly lower than those in group B and group C (P<0.05). CONCLUSION：Kupffer cells may play a regulatory role during host’s chronic HBV infection.