Background: Chemokines have strong chemoattractant effects and are involved in a variety of immune and inflammatory reactions, such as attracting activated T lymphocytes, neutrophils, monocytes and natural killer cells via the pathway of G protein-coupled receptors to sites of inflammatory injury and contribute to wound repair. This investigation was designed to assess the levels of chemokine interferon-gamma inducible protein-10 (IP-10) and IP-10 mRNA, and the relationship between IP-10 mRNA and HBV-DNA and alanine aminotransferase (ALT) in patients with chronic hepatitis B.
Methods: The levels of IP-10 mRNA in peripheral blood mononuclear cells (PBMCs) were kinetically detected by real-time polymerase chain reaction (PCR). The rate of chemokine/GAPDH was regarded as the extreme level of chemokine. The level of IP-10 in serum was measured by enzyme linked immunosorbent assay (ELISA), and the expression of IP-10 in hepatic biopsy tissue was detected by streptavidin-peroxidase (SP) immunohistochemistry.
Results: The level of IP-10 mRNA in the PBMCs of patients was 0.7387+/-0.0768 (lg cDNA/lg GAPDH); it was significantly higher in patients with chronic hepatitis B than that in normal controls (P<0.001). The level of IP-10 in the serum of patients was 660.9+/-75.5 pg/ml. There was a significant difference between patients with chronic hepatitis B and normal controls (P<0.05). In patients with chronic hepatitis B, the level of IP-10 mRNA in PBMCs was correlated with the IP-10 plasma level (r=0.7312, P<0.001), and the IP-10 plasma level was fairly correlated with the levels of ALT and HBV-DNA plasma (r=0.7235, P<0.001; r=0.7371, P<0.001). IP-10 was found by immunohistochemical analysis to be selectively upregulated on sinusoidal endothelium.
Conclusions: The expression of IP-10 mRNA in PBMCs, IP-10 plasma concentration and the expression of IP-10 in sinusoidal endothelium are all high in patients with chronic hepatitis B. Chemokine IP-10 may play an important role in trafficking inflammatory cells to the local focus in the liver and induce the development of the chronicity of hepatitis B.